Merge commit 'linus/master' into tracing/kprobes

Conflicts:
	kernel/trace/Makefile
	kernel/trace/trace.h
	kernel/trace/trace_event_types.h
	kernel/trace/trace_export.c

Merge reason:
	Sync with latest significant tracing core changes.

106 files changed, 12088 insertions, 12648 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index 2093a69..187c89b 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -80,26 +80,22 @@ obj-$(CONFIG_DETECT_HUNG_TASK) += hung_task.o
 obj-$(CONFIG_GENERIC_HARDIRQS) += irq/
 obj-$(CONFIG_SECCOMP) += seccomp.o
 obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o
-obj-$(CONFIG_CLASSIC_RCU) += rcuclassic.o
 obj-$(CONFIG_TREE_RCU) += rcutree.o
-obj-$(CONFIG_PREEMPT_RCU) += rcupreempt.o
+obj-$(CONFIG_TREE_PREEMPT_RCU) += rcutree.o
 obj-$(CONFIG_TREE_RCU_TRACE) += rcutree_trace.o
-obj-$(CONFIG_PREEMPT_RCU_TRACE) += rcupreempt_trace.o
 obj-$(CONFIG_RELAY) += relay.o
 obj-$(CONFIG_SYSCTL) += utsname_sysctl.o
 obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o
 obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o
-obj-$(CONFIG_MARKERS) += marker.o
 obj-$(CONFIG_TRACEPOINTS) += tracepoint.o
 obj-$(CONFIG_LATENCYTOP) += latencytop.o
-obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += dma-coherent.o
 obj-$(CONFIG_FUNCTION_TRACER) += trace/
 obj-$(CONFIG_TRACING) += trace/
 obj-$(CONFIG_X86_DS) += trace/
 obj-$(CONFIG_RING_BUFFER) += trace/
 obj-$(CONFIG_SMP) += sched_cpupri.o
 obj-$(CONFIG_SLOW_WORK) += slow-work.o
-obj-$(CONFIG_PERF_COUNTERS) += perf_counter.o
+obj-$(CONFIG_PERF_EVENTS) += perf_event.o
 
 ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER),y)
 # According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is
@@ -119,7 +115,7 @@ $(obj)/config_data.gz: .config FORCE
 	$(call if_changed,gzip)
 
 quiet_cmd_ikconfiggz = IKCFG   $@
-      cmd_ikconfiggz = (echo "static const char kernel_config_data[] = MAGIC_START"; cat $< | scripts/bin2c; echo "MAGIC_END;") > $@
+      cmd_ikconfiggz = (echo "static const char kernel_config_data[] __used = MAGIC_START"; cat $< | scripts/bin2c; echo "MAGIC_END;") > $@
 targets += config_data.h
 $(obj)/config_data.h: $(obj)/config_data.gz FORCE
 	$(call if_changed,ikconfiggz)
diff --git a/kernel/acct.c b/kernel/acct.c
index 9f33910..9a4715a 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -491,13 +491,17 @@ static void do_acct_process(struct bsd_acct_struct *acct,
 	u64 run_time;
 	struct timespec uptime;
 	struct tty_struct *tty;
+	const struct cred *orig_cred;
+
+	/* Perform file operations on behalf of whoever enabled accounting */
+	orig_cred = override_creds(file->f_cred);
 
 	/*
 	 * First check to see if there is enough free_space to continue
 	 * the process accounting system.
 	 */
 	if (!check_free_space(acct, file))
-		return;
+		goto out;
 
 	/*
 	 * Fill the accounting struct with the needed info as recorded
@@ -578,6 +582,8 @@ static void do_acct_process(struct bsd_acct_struct *acct,
 			       sizeof(acct_t), &file->f_pos);
 	current->signal->rlim[RLIMIT_FSIZE].rlim_cur = flim;
 	set_fs(fs);
+out:
+	revert_creds(orig_cred);
 }
 
 /**
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index b6eadfe..cd83d99 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -596,10 +596,11 @@ void cgroup_unlock(void)
 static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, int mode);
 static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry);
 static int cgroup_populate_dir(struct cgroup *cgrp);
-static struct inode_operations cgroup_dir_inode_operations;
+static const struct inode_operations cgroup_dir_inode_operations;
 static struct file_operations proc_cgroupstats_operations;
 
 static struct backing_dev_info cgroup_backing_dev_info = {
+	.name		= "cgroup",
 	.capabilities	= BDI_CAP_NO_ACCT_AND_WRITEBACK,
 };
 
@@ -960,7 +961,7 @@ static int cgroup_remount(struct super_block *sb, int *flags, char *data)
 	return ret;
 }
 
-static struct super_operations cgroup_ops = {
+static const struct super_operations cgroup_ops = {
 	.statfs = simple_statfs,
 	.drop_inode = generic_delete_inode,
 	.show_options = cgroup_show_options,
@@ -1710,7 +1711,7 @@ static struct file_operations cgroup_file_operations = {
 	.release = cgroup_file_release,
 };
 
-static struct inode_operations cgroup_dir_inode_operations = {
+static const struct inode_operations cgroup_dir_inode_operations = {
 	.lookup = simple_lookup,
 	.mkdir = cgroup_mkdir,
 	.rmdir = cgroup_rmdir,
@@ -2313,7 +2314,7 @@ static int cgroup_tasks_show(struct seq_file *s, void *v)
 	return seq_printf(s, "%d\n", *(int *)v);
 }
 
-static struct seq_operations cgroup_tasks_seq_operations = {
+static const struct seq_operations cgroup_tasks_seq_operations = {
 	.start = cgroup_tasks_start,
 	.stop = cgroup_tasks_stop,
 	.next = cgroup_tasks_next,
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 8ce1004..6ba0f1e 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -401,6 +401,7 @@ int disable_nonboot_cpus(void)
 			break;
 		}
 	}
+
 	if (!error) {
 		BUG_ON(num_online_cpus() > 1);
 		/* Make sure the CPUs won't be enabled by someone else */
@@ -413,6 +414,14 @@ int disable_nonboot_cpus(void)
 	return error;
 }
 
+void __weak arch_enable_nonboot_cpus_begin(void)
+{
+}
+
+void __weak arch_enable_nonboot_cpus_end(void)
+{
+}
+
 void __ref enable_nonboot_cpus(void)
 {
 	int cpu, error;
@@ -424,6 +433,9 @@ void __ref enable_nonboot_cpus(void)
 		goto out;
 
 	printk("Enabling non-boot CPUs ...\n");
+
+	arch_enable_nonboot_cpus_begin();
+
 	for_each_cpu(cpu, frozen_cpus) {
 		error = _cpu_up(cpu, 1);
 		if (!error) {
@@ -432,6 +444,9 @@ void __ref enable_nonboot_cpus(void)
 		}
 		printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error);
 	}
+
+	arch_enable_nonboot_cpus_end();
+
 	cpumask_clear(frozen_cpus);
 out:
 	cpu_maps_update_done();
diff --git a/kernel/cred.c b/kernel/cred.c
index 1bb4d7e..d7f7a01 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -18,6 +18,18 @@
 #include <linux/cn_proc.h>
 #include "cred-internals.h"
 
+#if 0
+#define kdebug(FMT, ...) \
+	printk("[%-5.5s%5u] "FMT"\n", current->comm, current->pid ,##__VA_ARGS__)
+#else
+static inline __attribute__((format(printf, 1, 2)))
+void no_printk(const char *fmt, ...)
+{
+}
+#define kdebug(FMT, ...) \
+	no_printk("[%-5.5s%5u] "FMT"\n", current->comm, current->pid ,##__VA_ARGS__)
+#endif
+
 static struct kmem_cache *cred_jar;
 
 /*
@@ -36,6 +48,10 @@ static struct thread_group_cred init_tgcred = {
  */
 struct cred init_cred = {
 	.usage			= ATOMIC_INIT(4),
+#ifdef CONFIG_DEBUG_CREDENTIALS
+	.subscribers		= ATOMIC_INIT(2),
+	.magic			= CRED_MAGIC,
+#endif
 	.securebits		= SECUREBITS_DEFAULT,
 	.cap_inheritable	= CAP_INIT_INH_SET,
 	.cap_permitted		= CAP_FULL_SET,
@@ -48,6 +64,31 @@ struct cred init_cred = {
 #endif
 };
 
+static inline void set_cred_subscribers(struct cred *cred, int n)
+{
+#ifdef CONFIG_DEBUG_CREDENTIALS
+	atomic_set(&cred->subscribers, n);
+#endif
+}
+
+static inline int read_cred_subscribers(const struct cred *cred)
+{
+#ifdef CONFIG_DEBUG_CREDENTIALS
+	return atomic_read(&cred->subscribers);
+#else
+	return 0;
+#endif
+}
+
+static inline void alter_cred_subscribers(const struct cred *_cred, int n)
+{
+#ifdef CONFIG_DEBUG_CREDENTIALS
+	struct cred *cred = (struct cred *) _cred;
+
+	atomic_add(n, &cred->subscribers);
+#endif
+}
+
 /*
  * Dispose of the shared task group credentials
  */
@@ -85,15 +126,29 @@ static void put_cred_rcu(struct rcu_head *rcu)
 {
 	struct cred *cred = container_of(rcu, struct cred, rcu);
 
+	kdebug("put_cred_rcu(%p)", cred);
+
+#ifdef CONFIG_DEBUG_CREDENTIALS
+	if (cred->magic != CRED_MAGIC_DEAD ||
+	    atomic_read(&cred->usage) != 0 ||
+	    read_cred_subscribers(cred) != 0)
+		panic("CRED: put_cred_rcu() sees %p with"
+		      " mag %x, put %p, usage %d, subscr %d\n",
+		      cred, cred->magic, cred->put_addr,
+		      atomic_read(&cred->usage),
+		      read_cred_subscribers(cred));
+#else
 	if (atomic_read(&cred->usage) != 0)
 		panic("CRED: put_cred_rcu() sees %p with usage %d\n",
 		      cred, atomic_read(&cred->usage));
+#endif
 
 	security_cred_free(cred);
 	key_put(cred->thread_keyring);
 	key_put(cred->request_key_auth);
 	release_tgcred(cred);
-	put_group_info(cred->group_info);
+	if (cred->group_info)
+		put_group_info(cred->group_info);
 	free_uid(cred->user);
 	kmem_cache_free(cred_jar, cred);
 }
@@ -106,12 +161,90 @@ static void put_cred_rcu(struct rcu_head *rcu)
  */
 void __put_cred(struct cred *cred)
 {
+	kdebug("__put_cred(%p{%d,%d})", cred,
+	       atomic_read(&cred->usage),
+	       read_cred_subscribers(cred));
+
 	BUG_ON(atomic_read(&cred->usage) != 0);
+#ifdef CONFIG_DEBUG_CREDENTIALS
+	BUG_ON(read_cred_subscribers(cred) != 0);
+	cred->magic = CRED_MAGIC_DEAD;
+	cred->put_addr = __builtin_return_address(0);
+#endif
+	BUG_ON(cred == current->cred);
+	BUG_ON(cred == current->real_cred);
 
 	call_rcu(&cred->rcu, put_cred_rcu);
 }
 EXPORT_SYMBOL(__put_cred);
 
+/*
+ * Clean up a task's credentials when it exits
+ */
+void exit_creds(struct task_struct *tsk)
+{
+	struct cred *cred;
+
+	kdebug("exit_creds(%u,%p,%p,{%d,%d})", tsk->pid, tsk->real_cred, tsk->cred,
+	       atomic_read(&tsk->cred->usage),
+	       read_cred_subscribers(tsk->cred));
+
+	cred = (struct cred *) tsk->real_cred;
+	tsk->real_cred = NULL;
+	validate_creds(cred);
+	alter_cred_subscribers(cred, -1);
+	put_cred(cred);
+
+	cred = (struct cred *) tsk->cred;
+	tsk->cred = NULL;
+	validate_creds(cred);
+	alter_cred_subscribers(cred, -1);
+	put_cred(cred);
+
+	cred = (struct cred *) tsk->replacement_session_keyring;
+	if (cred) {
+		tsk->replacement_session_keyring = NULL;
+		validate_creds(cred);
+		put_cred(cred);
+	}
+}
+
+/*
+ * Allocate blank credentials, such that the credentials can be filled in at a
+ * later date without risk of ENOMEM.
+ */
+struct cred *cred_alloc_blank(void)
+{
+	struct cred *new;
+
+	new = kmem_cache_zalloc(cred_jar, GFP_KERNEL);
+	if (!new)
+		return NULL;
+
+#ifdef CONFIG_KEYS
+	new->tgcred = kzalloc(sizeof(*new->tgcred), GFP_KERNEL);
+	if (!new->tgcred) {
+		kfree(new);
+		return NULL;
+	}
+	atomic_set(&new->tgcred->usage, 1);
+#endif
+
+	atomic_set(&new->usage, 1);
+
+	if (security_cred_alloc_blank(new, GFP_KERNEL) < 0)
+		goto error;
+
+#ifdef CONFIG_DEBUG_CREDENTIALS
+	new->magic = CRED_MAGIC;
+#endif
+	return new;
+
+error:
+	abort_creds(new);
+	return NULL;
+}
+
 /**
  * prepare_creds - Prepare a new set of credentials for modification
  *
@@ -132,16 +265,19 @@ struct cred *prepare_creds(void)
 	const struct cred *old;
 	struct cred *new;
 
-	BUG_ON(atomic_read(&task->real_cred->usage) < 1);
+	validate_process_creds();
 
 	new = kmem_cache_alloc(cred_jar, GFP_KERNEL);
 	if (!new)
 		return NULL;
 
+	kdebug("prepare_creds() alloc %p", new);
+
 	old = task->cred;
 	memcpy(new, old, sizeof(struct cred));
 
 	atomic_set(&new->usage, 1);
+	set_cred_subscribers(new, 0);
 	get_group_info(new->group_info);
 	get_uid(new->user);
 
@@ -157,6 +293,7 @@ struct cred *prepare_creds(void)
 
 	if (security_prepare_creds(new, old, GFP_KERNEL) < 0)
 		goto error;
+	validate_creds(new);
 	return new;
 
 error:
@@ -229,9 +366,12 @@ struct cred *prepare_usermodehelper_creds(void)
 	if (!new)
 		return NULL;
 
+	kdebug("prepare_usermodehelper_creds() alloc %p", new);
+
 	memcpy(new, &init_cred, sizeof(struct cred));
 
 	atomic_set(&new->usage, 1);
+	set_cred_subscribers(new, 0);
 	get_group_info(new->group_info);
 	get_uid(new->user);
 
@@ -250,6 +390,7 @@ struct cred *prepare_usermodehelper_creds(void)
 #endif
 	if (security_prepare_creds(new, &init_cred, GFP_ATOMIC) < 0)
 		goto error;
+	validate_creds(new);
 
 	BUG_ON(atomic_read(&new->usage) != 1);
 	return new;
@@ -286,6 +427,10 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags)
 	    ) {
 		p->real_cred = get_cred(p->cred);
 		get_cred(p->cred);
+		alter_cred_subscribers(p->cred, 2);
+		kdebug("share_creds(%p{%d,%d})",
+		       p->cred, atomic_read(&p->cred->usage),
+		       read_cred_subscribers(p->cred));
 		atomic_inc(&p->cred->user->processes);
 		return 0;
 	}
@@ -331,6 +476,8 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags)
 
 	atomic_inc(&new->user->processes);
 	p->cred = p->real_cred = get_cred(new);
+	alter_cred_subscribers(new, 2);
+	validate_creds(new);
 	return 0;
 
 error_put:
@@ -355,13 +502,20 @@ error_put:
 int commit_creds(struct cred *new)
 {
 	struct task_struct *task = current;
-	const struct cred *old;
+	const struct cred *old = task->real_cred;
 
-	BUG_ON(task->cred != task->real_cred);
-	BUG_ON(atomic_read(&task->real_cred->usage) < 2);
+	kdebug("commit_creds(%p{%d,%d})", new,
+	       atomic_read(&new->usage),
+	       read_cred_subscribers(new));
+
+	BUG_ON(task->cred != old);
+#ifdef CONFIG_DEBUG_CREDENTIALS
+	BUG_ON(read_cred_subscribers(old) < 2);
+	validate_creds(old);
+	validate_creds(new);
+#endif
 	BUG_ON(atomic_read(&new->usage) < 1);
 
-	old = task->real_cred;
 	security_commit_creds(new, old);
 
 	get_cred(new); /* we will require a ref for the subj creds too */
@@ -390,12 +544,14 @@ int commit_creds(struct cred *new)
 	 *   cheaply with the new uid cache, so if it matters
 	 *   we should be checking for it.  -DaveM
 	 */
+	alter_cred_subscribers(new, 2);
 	if (new->user != old->user)
 		atomic_inc(&new->user->processes);
 	rcu_assign_pointer(task->real_cred, new);
 	rcu_assign_pointer(task->cred, new);
 	if (new->user != old->user)
 		atomic_dec(&old->user->processes);
+	alter_cred_subscribers(old, -2);
 
 	sched_switch_user(task);
 
@@ -428,6 +584,13 @@ EXPORT_SYMBOL(commit_creds);
  */
 void abort_creds(struct cred *new)
 {
+	kdebug("abort_creds(%p{%d,%d})", new,
+	       atomic_read(&new->usage),
+	       read_cred_subscribers(new));
+
+#ifdef CONFIG_DEBUG_CREDENTIALS
+	BUG_ON(read_cred_subscribers(new) != 0);
+#endif
 	BUG_ON(atomic_read(&new->usage) < 1);
 	put_cred(new);
 }
@@ -444,7 +607,20 @@ const struct cred *override_creds(const struct cred *new)
 {
 	const struct cred *old = current->cred;
 
-	rcu_assign_pointer(current->cred, get_cred(new));
+	kdebug("override_creds(%p{%d,%d})", new,
+	       atomic_read(&new->usage),
+	       read_cred_subscribers(new));
+
+	validate_creds(old);
+	validate_creds(new);
+	get_cred(new);
+	alter_cred_subscribers(new, 1);
+	rcu_assign_pointer(current->cred, new);
+	alter_cred_subscribers(old, -1);
+
+	kdebug("override_creds() = %p{%d,%d}", old,
+	       atomic_read(&old->usage),
+	       read_cred_subscribers(old));
 	return old;
 }
 EXPORT_SYMBOL(override_creds);
@@ -460,7 +636,15 @@ void revert_creds(const struct cred *old)
 {
 	const struct cred *override = current->cred;
 
+	kdebug("revert_creds(%p{%d,%d})", old,
+	       atomic_read(&old->usage),
+	       read_cred_subscribers(old));
+
+	validate_creds(old);
+	validate_creds(override);
+	alter_cred_subscribers(old, 1);
 	rcu_assign_pointer(current->cred, old);
+	alter_cred_subscribers(override, -1);
 	put_cred(override);
 }
 EXPORT_SYMBOL(revert_creds);
@@ -502,11 +686,15 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon)
 	if (!new)
 		return NULL;
 
+	kdebug("prepare_kernel_cred() alloc %p", new);
+
 	if (daemon)
 		old = get_task_cred(daemon);
 	else
 		old = get_cred(&init_cred);
 
+	validate_creds(old);
+
 	*new = *old;
 	get_uid(new->user);
 	get_group_info(new->group_info);
@@ -526,7 +714,9 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon)
 		goto error;
 
 	atomic_set(&new->usage, 1);
+	set_cred_subscribers(new, 0);
 	put_cred(old);
+	validate_creds(new);
 	return new;
 
 error:
@@ -589,3 +779,95 @@ int set_create_files_as(struct cred *new, struct inode *inode)
 	return security_kernel_create_files_as(new, inode);
 }
 EXPORT_SYMBOL(set_create_files_as);
+
+#ifdef CONFIG_DEBUG_CREDENTIALS
+
+/*
+ * dump invalid credentials
+ */
+static void dump_invalid_creds(const struct cred *cred, const char *label,
+			       const struct task_struct *tsk)
+{
+	printk(KERN_ERR "CRED: %s credentials: %p %s%s%s\n",
+	       label, cred,
+	       cred == &init_cred ? "[init]" : "",
+	       cred == tsk->real_cred ? "[real]" : "",
+	       cred == tsk->cred ? "[eff]" : "");
+	printk(KERN_ERR "CRED: ->magic=%x, put_addr=%p\n",
+	       cred->magic, cred->put_addr);
+	printk(KERN_ERR "CRED: ->usage=%d, subscr=%d\n",
+	       atomic_read(&cred->usage),
+	       read_cred_subscribers(cred));
+	printk(KERN_ERR "CRED: ->*uid = { %d,%d,%d,%d }\n",
+	       cred->uid, cred->euid, cred->suid, cred->fsuid);
+	printk(KERN_ERR "CRED: ->*gid = { %d,%d,%d,%d }\n",
+	       cred->gid, cred->egid, cred->sgid, cred->fsgid);
+#ifdef CONFIG_SECURITY
+	printk(KERN_ERR "CRED: ->security is %p\n", cred->security);
+	if ((unsigned long) cred->security >= PAGE_SIZE &&
+	    (((unsigned long) cred->security & 0xffffff00) !=
+	     (POISON_FREE << 24 | POISON_FREE << 16 | POISON_FREE << 8)))
+		printk(KERN_ERR "CRED: ->security {%x, %x}\n",
+		       ((u32*)cred->security)[0],
+		       ((u32*)cred->security)[1]);
+#endif
+}
+
+/*
+ * report use of invalid credentials
+ */
+void __invalid_creds(const struct cred *cred, const char *file, unsigned line)
+{
+	printk(KERN_ERR "CRED: Invalid credentials\n");
+	printk(KERN_ERR "CRED: At %s:%u\n", file, line);
+	dump_invalid_creds(cred, "Specified", current);
+	BUG();
+}
+EXPORT_SYMBOL(__invalid_creds);
+
+/*
+ * check the credentials on a process
+ */
+void __validate_process_creds(struct task_struct *tsk,
+			      const char *file, unsigned line)
+{
+	if (tsk->cred == tsk->real_cred) {
+		if (unlikely(read_cred_subscribers(tsk->cred) < 2 ||
+			     creds_are_invalid(tsk->cred)))
+			goto invalid_creds;
+	} else {
+		if (unlikely(read_cred_subscribers(tsk->real_cred) < 1 ||
+			     read_cred_subscribers(tsk->cred) < 1 ||
+			     creds_are_invalid(tsk->real_cred) ||
+			     creds_are_invalid(tsk->cred)))
+			goto invalid_creds;
+	}
+	return;
+
+invalid_creds:
+	printk(KERN_ERR "CRED: Invalid process credentials\n");
+	printk(KERN_ERR "CRED: At %s:%u\n", file, line);
+
+	dump_invalid_creds(tsk->real_cred, "Real", tsk);
+	if (tsk->cred != tsk->real_cred)
+		dump_invalid_creds(tsk->cred, "Effective", tsk);
+	else
+		printk(KERN_ERR "CRED: Effective creds == Real creds\n");
+	BUG();
+}
+EXPORT_SYMBOL(__validate_process_creds);
+
+/*
+ * check creds for do_exit()
+ */
+void validate_creds_for_do_exit(struct task_struct *tsk)
+{
+	kdebug("validate_creds_for_do_exit(%p,%p{%d,%d})",
+	       tsk->real_cred, tsk->cred,
+	       atomic_read(&tsk->cred->usage),
+	       read_cred_subscribers(tsk->cred));
+
+	__validate_process_creds(tsk, __FILE__, __LINE__);
+}
+
+#endif /* CONFIG_DEBUG_CREDENTIALS */
diff --git a/kernel/delayacct.c b/kernel/delayacct.c
index abb6e17..ead9b61 100644
--- a/kernel/delayacct.c
+++ b/kernel/delayacct.c
@@ -15,6 +15,7 @@
 
 #include <linux/sched.h>
 #include <linux/slab.h>
+#include <linux/taskstats.h>
 #include <linux/time.h>
 #include <linux/sysctl.h>
 #include <linux/delayacct.h>
diff --git a/kernel/dma-coherent.c b/kernel/dma-coherent.c
deleted file mode 100644
index 962a3b5..0000000
--- a/kernel/dma-coherent.c
+++ /dev/null
@@ -1,176 +0,0 @@
-/*
- * Coherent per-device memory handling.
- * Borrowed from i386
- */
-#include <linux/kernel.h>
-#include <linux/dma-mapping.h>
-
-struct dma_coherent_mem {
-	void		*virt_base;
-	u32		device_base;
-	int		size;
-	int		flags;
-	unsigned long	*bitmap;
-};
-
-int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
-				dma_addr_t device_addr, size_t size, int flags)
-{
-	void __iomem *mem_base = NULL;
-	int pages = size >> PAGE_SHIFT;
-	int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
-
-	if ((flags & (DMA_MEMORY_MAP | DMA_MEMORY_IO)) == 0)
-		goto out;
-	if (!size)
-		goto out;
-	if (dev->dma_mem)
-		goto out;
-
-	/* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */
-
-	mem_base = ioremap(bus_addr, size);
-	if (!mem_base)
-		goto out;
-
-	dev->dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL);
-	if (!dev->dma_mem)
-		goto out;
-	dev->dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
-	if (!dev->dma_mem->bitmap)
-		goto free1_out;
-
-	dev->dma_mem->virt_base = mem_base;
-	dev->dma_mem->device_base = device_addr;
-	dev->dma_mem->size = pages;
-	dev->dma_mem->flags = flags;
-
-	if (flags & DMA_MEMORY_MAP)
-		return DMA_MEMORY_MAP;
-
-	return DMA_MEMORY_IO;
-
- free1_out:
-	kfree(dev->dma_mem);
- out:
-	if (mem_base)
-		iounmap(mem_base);
-	return 0;
-}
-EXPORT_SYMBOL(dma_declare_coherent_memory);
-
-void dma_release_declared_memory(struct device *dev)
-{
-	struct dma_coherent_mem *mem = dev->dma_mem;
-
-	if (!mem)
-		return;
-	dev->dma_mem = NULL;
-	iounmap(mem->virt_base);
-	kfree(mem->bitmap);
-	kfree(mem);
-}
-EXPORT_SYMBOL(dma_release_declared_memory);
-
-void *dma_mark_declared_memory_occupied(struct device *dev,
-					dma_addr_t device_addr, size_t size)
-{
-	struct dma_coherent_mem *mem = dev->dma_mem;
-	int pos, err;
-
-	size += device_addr & ~PAGE_MASK;
-
-	if (!mem)
-		return ERR_PTR(-EINVAL);
-
-	pos = (device_addr - mem->device_base) >> PAGE_SHIFT;
-	err = bitmap_allocate_region(mem->bitmap, pos, get_order(size));
-	if (err != 0)
-		return ERR_PTR(err);
-	return mem->virt_base + (pos << PAGE_SHIFT);
-}
-EXPORT_SYMBOL(dma_mark_declared_memory_occupied);
-
-/**
- * dma_alloc_from_coherent() - try to allocate memory from the per-device coherent area
- *
- * @dev:	device from which we allocate memory
- * @size:	size of requested memory area
- * @dma_handle:	This will be filled with the correct dma handle
- * @ret:	This pointer will be filled with the virtual address
- *		to allocated area.
- *
- * This function should be only called from per-arch dma_alloc_coherent()
- * to support allocation from per-device coherent memory pools.
- *
- * Returns 0 if dma_alloc_coherent should continue with allocating from
- * generic memory areas, or !0 if dma_alloc_coherent should return @ret.
- */
-int dma_alloc_from_coherent(struct device *dev, ssize_t size,
-				       dma_addr_t *dma_handle, void **ret)
-{
-	struct dma_coherent_mem *mem;
-	int order = get_order(size);
-	int pageno;
-
-	if (!dev)
-		return 0;
-	mem = dev->dma_mem;
-	if (!mem)
-		return 0;
-
-	*ret = NULL;
-
-	if (unlikely(size > (mem->size << PAGE_SHIFT)))
-		goto err;
-
-	pageno = bitmap_find_free_region(mem->bitmap, mem->size, order);
-	if (unlikely(pageno < 0))
-		goto err;
-
-	/*
-	 * Memory was found in the per-device area.
-	 */
-	*dma_handle = mem->device_base + (pageno << PAGE_SHIFT);
-	*ret = mem->virt_base + (pageno << PAGE_SHIFT);
-	memset(*ret, 0, size);
-
-	return 1;
-
-err:
-	/*
-	 * In the case where the allocation can not be satisfied from the
-	 * per-device area, try to fall back to generic memory if the
-	 * constraints allow it.
-	 */
-	return mem->flags & DMA_MEMORY_EXCLUSIVE;
-}
-EXPORT_SYMBOL(dma_alloc_from_coherent);
-
-/**
- * dma_release_from_coherent() - try to free the memory allocated from per-device coherent memory pool
- * @dev:	device from which the memory was allocated
- * @order:	the order of pages allocated
- * @vaddr:	virtual address of allocated pages
- *
- * This checks whether the memory was allocated from the per-device
- * coherent memory pool and if so, releases that memory.
- *
- * Returns 1 if we correctly released the memory, or 0 if
- * dma_release_coherent() should proceed with releasing memory from
- * generic pools.
- */
-int dma_release_from_coherent(struct device *dev, int order, void *vaddr)
-{
-	struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
-
-	if (mem && vaddr >= mem->virt_base && vaddr <
-		   (mem->virt_base + (mem->size << PAGE_SHIFT))) {
-		int page = (vaddr - mem->virt_base) >> PAGE_SHIFT;
-
-		bitmap_release_region(mem->bitmap, page, order);
-		return 1;
-	}
-	return 0;
-}
-EXPORT_SYMBOL(dma_release_from_coherent);
diff --git a/kernel/exit.c b/kernel/exit.c
index 869dc22..60d6fdc 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -47,7 +47,7 @@
 #include <linux/tracehook.h>
 #include <linux/fs_struct.h>
 #include <linux/init_task.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
 #include <trace/events/sched.h>
 
 #include <asm/uaccess.h>
@@ -154,8 +154,8 @@ static void delayed_put_task_struct(struct rcu_head *rhp)
 {
 	struct task_struct *tsk = container_of(rhp, struct task_struct, rcu);
 
-#ifdef CONFIG_PERF_COUNTERS
-	WARN_ON_ONCE(tsk->perf_counter_ctxp);
+#ifdef CONFIG_PERF_EVENTS
+	WARN_ON_ONCE(tsk->perf_event_ctxp);
 #endif
 	trace_sched_process_free(tsk);
 	put_task_struct(tsk);
@@ -359,8 +359,10 @@ void __set_special_pids(struct pid *pid)
 {
 	struct task_struct *curr = current->group_leader;
 
-	if (task_session(curr) != pid)
+	if (task_session(curr) != pid) {
 		change_pid(curr, PIDTYPE_SID, pid);
+		proc_sid_connector(curr);
+	}
 
 	if (task_pgrp(curr) != pid)
 		change_pid(curr, PIDTYPE_PGID, pid);
@@ -901,6 +903,8 @@ NORET_TYPE void do_exit(long code)
 
 	tracehook_report_exit(&code);
 
+	validate_creds_for_do_exit(tsk);
+
 	/*
 	 * We're taking recursive faults here in do_exit. Safest is to just
 	 * leave this task alone and wait for reboot.
@@ -943,6 +947,8 @@ NORET_TYPE void do_exit(long code)
 	if (group_dead) {
 		hrtimer_cancel(&tsk->signal->real_timer);
 		exit_itimers(tsk->signal);
+		if (tsk->mm)
+			setmax_mm_hiwater_rss(&tsk->signal->maxrss, tsk->mm);
 	}
 	acct_collect(code, group_dead);
 	if (group_dead)
@@ -979,7 +985,7 @@ NORET_TYPE void do_exit(long code)
 	 * Flush inherited counters to the parent - before the parent
 	 * gets woken up by child-exit notifications.
 	 */
-	perf_counter_exit_task(tsk);
+	perf_event_exit_task(tsk);
 
 	exit_notify(tsk, group_dead);
 #ifdef CONFIG_NUMA
@@ -1009,7 +1015,10 @@ NORET_TYPE void do_exit(long code)
 	if (tsk->splice_pipe)
 		__free_pipe_info(tsk->splice_pipe);
 
+	validate_creds_for_do_exit(tsk);
+
 	preempt_disable();
+	exit_rcu();
 	/* causes final put_task_struct in finish_task_switch(). */
 	tsk->state = TASK_DEAD;
 	schedule();
@@ -1203,6 +1212,7 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
 	if (likely(!traced) && likely(!task_detached(p))) {
 		struct signal_struct *psig;
 		struct signal_struct *sig;
+		unsigned long maxrss;
 
 		/*
 		 * The resource counters for the group leader are in its
@@ -1251,6 +1261,9 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
 		psig->coublock +=
 			task_io_get_oublock(p) +
 			sig->oublock + sig->coublock;
+		maxrss = max(sig->maxrss, sig->cmaxrss);
+		if (psig->cmaxrss < maxrss)
+			psig->cmaxrss = maxrss;
 		task_io_accounting_add(&psig->ioac, &p->ioac);
 		task_io_accounting_add(&psig->ioac, &sig->ioac);
 		spin_unlock_irq(&p->real_parent->sighand->siglock);
diff --git a/kernel/fork.c b/kernel/fork.c
index e6c04d4..51ad0b0 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -49,6 +49,7 @@
 #include <linux/ftrace.h>
 #include <linux/profile.h>
 #include <linux/rmap.h>
+#include <linux/ksm.h>
 #include <linux/acct.h>
 #include <linux/tsacct_kern.h>
 #include <linux/cn_proc.h>
@@ -61,7 +62,8 @@
 #include <linux/blkdev.h>
 #include <linux/fs_struct.h>
 #include <linux/magic.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
+#include <linux/posix-timers.h>
 
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
@@ -136,9 +138,17 @@ struct kmem_cache *vm_area_cachep;
 /* SLAB cache for mm_struct structures (tsk->mm) */
 static struct kmem_cache *mm_cachep;
 
+static void account_kernel_stack(struct thread_info *ti, int account)
+{
+	struct zone *zone = page_zone(virt_to_page(ti));
+
+	mod_zone_page_state(zone, NR_KERNEL_STACK, account);
+}
+
 void free_task(struct task_struct *tsk)
 {
 	prop_local_destroy_single(&tsk->dirties);
+	account_kernel_stack(tsk->stack, -1);
 	free_thread_info(tsk->stack);
 	rt_mutex_debug_task_free(tsk);
 	ftrace_graph_exit_task(tsk);
@@ -152,8 +162,7 @@ void __put_task_struct(struct task_struct *tsk)
 	WARN_ON(atomic_read(&tsk->usage));
 	WARN_ON(tsk == current);
 
-	put_cred(tsk->real_cred);
-	put_cred(tsk->cred);
+	exit_creds(tsk);
 	delayacct_tsk_free(tsk);
 
 	if (!profile_handoff_task(tsk))
@@ -254,6 +263,9 @@ static struct task_struct *dup_task_struct(struct task_struct *orig)
 	tsk->btrace_seq = 0;
 #endif
 	tsk->splice_pipe = NULL;
+
+	account_kernel_stack(ti, 1);
+
 	return tsk;
 
 out:
@@ -289,6 +301,9 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
 	rb_link = &mm->mm_rb.rb_node;
 	rb_parent = NULL;
 	pprev = &mm->mmap;
+	retval = ksm_fork(mm, oldmm);
+	if (retval)
+		goto out;
 
 	for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) {
 		struct file *file;
@@ -425,7 +440,8 @@ static struct mm_struct * mm_init(struct mm_struct * mm, struct task_struct *p)
 	atomic_set(&mm->mm_count, 1);
 	init_rwsem(&mm->mmap_sem);
 	INIT_LIST_HEAD(&mm->mmlist);
-	mm->flags = (current->mm) ? current->mm->flags : default_dump_filter;
+	mm->flags = (current->mm) ?
+		(current->mm->flags & MMF_INIT_MASK) : default_dump_filter;
 	mm->core_state = NULL;
 	mm->nr_ptes = 0;
 	set_mm_counter(mm, file_rss, 0);
@@ -486,6 +502,7 @@ void mmput(struct mm_struct *mm)
 
 	if (atomic_dec_and_test(&mm->mm_users)) {
 		exit_aio(mm);
+		ksm_exit(mm);
 		exit_mmap(mm);
 		set_mm_exe_file(mm, NULL);
 		if (!list_empty(&mm->mmlist)) {
@@ -789,10 +806,10 @@ static void posix_cpu_timers_init_group(struct signal_struct *sig)
 	thread_group_cputime_init(sig);
 
 	/* Expiration times and increments. */
-	sig->it_virt_expires = cputime_zero;
-	sig->it_virt_incr = cputime_zero;
-	sig->it_prof_expires = cputime_zero;
-	sig->it_prof_incr = cputime_zero;
+	sig->it[CPUCLOCK_PROF].expires = cputime_zero;
+	sig->it[CPUCLOCK_PROF].incr = cputime_zero;
+	sig->it[CPUCLOCK_VIRT].expires = cputime_zero;
+	sig->it[CPUCLOCK_VIRT].incr = cputime_zero;
 
 	/* Cached expiration times. */
 	sig->cputime_expires.prof_exp = cputime_zero;
@@ -850,6 +867,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
 	sig->nvcsw = sig->nivcsw = sig->cnvcsw = sig->cnivcsw = 0;
 	sig->min_flt = sig->maj_flt = sig->cmin_flt = sig->cmaj_flt = 0;
 	sig->inblock = sig->oublock = sig->cinblock = sig->coublock = 0;
+	sig->maxrss = sig->cmaxrss = 0;
 	task_io_accounting_init(&sig->ioac);
 	sig->sum_sched_runtime = 0;
 	taskstats_tgid_init(sig);
@@ -864,6 +882,8 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
 
 	tty_audit_fork(sig);
 
+	sig->oom_adj = current->signal->oom_adj;
+
 	return 0;
 }
 
@@ -1008,10 +1028,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 	copy_flags(clone_flags, p);
 	INIT_LIST_HEAD(&p->children);
 	INIT_LIST_HEAD(&p->sibling);
-#ifdef CONFIG_PREEMPT_RCU
-	p->rcu_read_lock_nesting = 0;
-	p->rcu_flipctr_idx = 0;
-#endif /* #ifdef CONFIG_PREEMPT_RCU */
+	rcu_copy_process(p);
 	p->vfork_done = NULL;
 	spin_lock_init(&p->alloc_lock);
 
@@ -1079,10 +1096,12 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 
 	p->bts = NULL;
 
+	p->stack_start = stack_start;
+
 	/* Perform scheduler related setup. Assign this task to a CPU. */
 	sched_fork(p, clone_flags);
 
-	retval = perf_counter_init_task(p);
+	retval = perf_event_init_task(p);
 	if (retval)
 		goto bad_fork_cleanup_policy;
 
@@ -1257,7 +1276,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 	write_unlock_irq(&tasklist_lock);
 	proc_fork_connector(p);
 	cgroup_post_fork(p);
-	perf_counter_fork(p);
+	perf_event_fork(p);
 	return p;
 
 bad_fork_free_pid:
@@ -1284,7 +1303,7 @@ bad_fork_cleanup_semundo:
 bad_fork_cleanup_audit:
 	audit_free(p);
 bad_fork_cleanup_policy:
-	perf_counter_free_task(p);
+	perf_event_free_task(p);
 #ifdef CONFIG_NUMA
 	mpol_put(p->mempolicy);
 bad_fork_cleanup_cgroup:
@@ -1297,8 +1316,7 @@ bad_fork_cleanup_put_domain:
 	module_put(task_thread_info(p)->exec_domain->module);
 bad_fork_cleanup_count:
 	atomic_dec(&p->cred->user->processes);
-	put_cred(p->real_cred);
-	put_cred(p->cred);
+	exit_creds(p);
 bad_fork_free:
 	free_task(p);
 fork_out:
diff --git a/kernel/futex.c b/kernel/futex.c
index e18cfbd..248dd11 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -115,6 +115,9 @@ struct futex_q {
 	/* rt_waiter storage for requeue_pi: */
 	struct rt_mutex_waiter *rt_waiter;
 
+	/* The expected requeue pi target futex key: */
+	union futex_key *requeue_pi_key;
+
 	/* Bitset for the optional bitmasked wakeup */
 	u32 bitset;
 };
@@ -1089,6 +1092,10 @@ static int futex_proxy_trylock_atomic(u32 __user *pifutex,
 	if (!top_waiter)
 		return 0;
 
+	/* Ensure we requeue to the expected futex. */
+	if (!match_futex(top_waiter->requeue_pi_key, key2))
+		return -EINVAL;
+
 	/*
 	 * Try to take the lock for top_waiter.  Set the FUTEX_WAITERS bit in
 	 * the contended case or if set_waiters is 1.  The pi_state is returned
@@ -1276,6 +1283,12 @@ retry_private:
 			continue;
 		}
 
+		/* Ensure we requeue to the expected futex for requeue_pi. */
+		if (requeue_pi && !match_futex(this->requeue_pi_key, &key2)) {
+			ret = -EINVAL;
+			break;
+		}
+
 		/*
 		 * Requeue nr_requeue waiters and possibly one more in the case
 		 * of requeue_pi if we couldn't acquire the lock atomically.
@@ -1751,6 +1764,7 @@ static int futex_wait(u32 __user *uaddr, int fshared,
 	q.pi_state = NULL;
 	q.bitset = bitset;
 	q.rt_waiter = NULL;
+	q.requeue_pi_key = NULL;
 
 	if (abs_time) {
 		to = &timeout;
@@ -1858,6 +1872,7 @@ static int futex_lock_pi(u32 __user *uaddr, int fshared,
 
 	q.pi_state = NULL;
 	q.rt_waiter = NULL;
+	q.requeue_pi_key = NULL;
 retry:
 	q.key = FUTEX_KEY_INIT;
 	ret = get_futex_key(uaddr, fshared, &q.key, VERIFY_WRITE);
@@ -2118,11 +2133,11 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
  * We call schedule in futex_wait_queue_me() when we enqueue and return there
  * via the following:
  * 1) wakeup on uaddr2 after an atomic lock acquisition by futex_requeue()
- * 2) wakeup on uaddr2 after a requeue and subsequent unlock
- * 3) signal (before or after requeue)
- * 4) timeout (before or after requeue)
+ * 2) wakeup on uaddr2 after a requeue
+ * 3) signal
+ * 4) timeout
  *
- * If 3, we setup a restart_block with futex_wait_requeue_pi() as the function.
+ * If 3, cleanup and return -ERESTARTNOINTR.
  *
  * If 2, we may then block on trying to take the rt_mutex and return via:
  * 5) successful lock
@@ -2130,7 +2145,7 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
  * 7) timeout
  * 8) other lock acquisition failure
  *
- * If 6, we setup a restart_block with futex_lock_pi() as the function.
+ * If 6, return -EWOULDBLOCK (restarting the syscall would do the same).
  *
  * If 4 or 7, we cleanup and return with -ETIMEDOUT.
  *
@@ -2169,15 +2184,16 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared,
 	debug_rt_mutex_init_waiter(&rt_waiter);
 	rt_waiter.task = NULL;
 
-	q.pi_state = NULL;
-	q.bitset = bitset;
-	q.rt_waiter = &rt_waiter;
-
 	key2 = FUTEX_KEY_INIT;
 	ret = get_futex_key(uaddr2, fshared, &key2, VERIFY_WRITE);
 	if (unlikely(ret != 0))
 		goto out;
 
+	q.pi_state = NULL;
+	q.bitset = bitset;
+	q.rt_waiter = &rt_waiter;
+	q.requeue_pi_key = &key2;
+
 	/* Prepare to wait on uaddr. */
 	ret = futex_wait_setup(uaddr, val, fshared, &q, &hb);
 	if (ret)
@@ -2248,14 +2264,11 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared,
 			rt_mutex_unlock(pi_mutex);
 	} else if (ret == -EINTR) {
 		/*
-		 * We've already been requeued, but we have no way to
-		 * restart by calling futex_lock_pi() directly. We
-		 * could restart the syscall, but that will look at
-		 * the user space value and return right away. So we
-		 * drop back with EWOULDBLOCK to tell user space that
-		 * "val" has been changed. That's the same what the
-		 * restart of the syscall would do in
-		 * futex_wait_setup().
+		 * We've already been requeued, but cannot restart by calling
+		 * futex_lock_pi() directly. We could restart this syscall, but
+		 * it would detect that the user space "val" changed and return
+		 * -EWOULDBLOCK.  Save the overhead of the restart and return
+		 * -EWOULDBLOCK directly.
 		 */
 		ret = -EWOULDBLOCK;
 	}
diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig
index 22e9dcf..654efd0 100644
--- a/kernel/gcov/Kconfig
+++ b/kernel/gcov/Kconfig
@@ -34,7 +34,7 @@ config GCOV_KERNEL
 config GCOV_PROFILE_ALL
 	bool "Profile entire Kernel"
 	depends on GCOV_KERNEL
-	depends on S390 || X86
+	depends on S390 || X86 || (PPC && EXPERIMENTAL)
 	default n
 	---help---
 	This options activates profiling for the entire kernel.
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 49da79a..e5d98ce 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -48,36 +48,7 @@
 
 #include <asm/uaccess.h>
 
-/**
- * ktime_get - get the monotonic time in ktime_t format
- *
- * returns the time in ktime_t format
- */
-ktime_t ktime_get(void)
-{
-	struct timespec now;
-
-	ktime_get_ts(&now);
-
-	return timespec_to_ktime(now);
-}
-EXPORT_SYMBOL_GPL(ktime_get);
-
-/**
- * ktime_get_real - get the real (wall-) time in ktime_t format
- *
- * returns the time in ktime_t format
- */
-ktime_t ktime_get_real(void)
-{
-	struct timespec now;
-
-	getnstimeofday(&now);
-
-	return timespec_to_ktime(now);
-}
-
-EXPORT_SYMBOL_GPL(ktime_get_real);
+#include <trace/events/timer.h>
 
 /*
  * The timer bases:
@@ -106,31 +77,6 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
 	}
 };
 
-/**
- * ktime_get_ts - get the monotonic clock in timespec format
- * @ts:		pointer to timespec variable
- *
- * The function calculates the monotonic clock from the realtime
- * clock and the wall_to_monotonic offset and stores the result
- * in normalized timespec format in the variable pointed to by @ts.
- */
-void ktime_get_ts(struct timespec *ts)
-{
-	struct timespec tomono;
-	unsigned long seq;
-
-	do {
-		seq = read_seqbegin(&xtime_lock);
-		getnstimeofday(ts);
-		tomono = wall_to_monotonic;
-
-	} while (read_seqretry(&xtime_lock, seq));
-
-	set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
-				ts->tv_nsec + tomono.tv_nsec);
-}
-EXPORT_SYMBOL_GPL(ktime_get_ts);
-
 /*
  * Get the coarse grained time at the softirq based on xtime and
  * wall_to_monotonic.
@@ -485,6 +431,7 @@ void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t clock_id,
 	debug_object_init_on_stack(timer, &hrtimer_debug_descr);
 	__hrtimer_init(timer, clock_id, mode);
 }
+EXPORT_SYMBOL_GPL(hrtimer_init_on_stack);
 
 void destroy_hrtimer_on_stack(struct hrtimer *timer)
 {
@@ -497,6 +444,26 @@ static inline void debug_hrtimer_activate(struct hrtimer *timer) { }
 static inline void debug_hrtimer_deactivate(struct hrtimer *timer) { }
 #endif
 
+static inline void
+debug_init(struct hrtimer *timer, clockid_t clockid,
+	   enum hrtimer_mode mode)
+{
+	debug_hrtimer_init(timer);
+	trace_hrtimer_init(timer, clockid, mode);
+}
+
+static inline void debug_activate(struct hrtimer *timer)
+{
+	debug_hrtimer_activate(timer);
+	trace_hrtimer_start(timer);
+}
+
+static inline void debug_deactivate(struct hrtimer *timer)
+{
+	debug_hrtimer_deactivate(timer);
+	trace_hrtimer_cancel(timer);
+}
+
 /* High resolution timer related functions */
 #ifdef CONFIG_HIGH_RES_TIMERS
 
@@ -853,7 +820,7 @@ static int enqueue_hrtimer(struct hrtimer *timer,
 	struct hrtimer *entry;
 	int leftmost = 1;
 
-	debug_hrtimer_activate(timer);
+	debug_activate(timer);
 
 	/*
 	 * Find the right place in the rbtree:
@@ -939,7 +906,7 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base)
 		 * reprogramming happens in the interrupt handler. This is a
 		 * rare case and less expensive than a smp call.
 		 */
-		debug_hrtimer_deactivate(timer);
+		debug_deactivate(timer);
 		timer_stats_hrtimer_clear_start_info(timer);
 		reprogram = base->cpu_base == &__get_cpu_var(hrtimer_bases);
 		__remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE,
@@ -1154,7 +1121,6 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 		clock_id = CLOCK_MONOTONIC;
 
 	timer->base = &cpu_base->clock_base[clock_id];
-	INIT_LIST_HEAD(&timer->cb_entry);
 	hrtimer_init_timer_hres(timer);
 
 #ifdef CONFIG_TIMER_STATS
@@ -1173,7 +1139,7 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 		  enum hrtimer_mode mode)
 {
-	debug_hrtimer_init(timer);
+	debug_init(timer, clock_id, mode);
 	__hrtimer_init(timer, clock_id, mode);
 }
 EXPORT_SYMBOL_GPL(hrtimer_init);
@@ -1197,7 +1163,7 @@ int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp)
 }
 EXPORT_SYMBOL_GPL(hrtimer_get_res);
 
-static void __run_hrtimer(struct hrtimer *timer)
+static void __run_hrtimer(struct hrtimer *timer, ktime_t *now)
 {
 	struct hrtimer_clock_base *base = timer->base;
 	struct hrtimer_cpu_base *cpu_base = base->cpu_base;
@@ -1206,7 +1172,7 @@ static void __run_hrtimer(struct hrtimer *timer)
 
 	WARN_ON(!irqs_disabled());
 
-	debug_hrtimer_deactivate(timer);
+	debug_deactivate(timer);
 	__remove_hrtimer(timer, base, HRTIMER_STATE_CALLBACK, 0);
 	timer_stats_account_hrtimer(timer);
 	fn = timer->function;
@@ -1217,7 +1183,9 @@ static void __run_hrtimer(struct hrtimer *timer)
 	 * the timer base.
 	 */
 	spin_unlock(&cpu_base->lock);
+	trace_hrtimer_expire_entry(timer, now);
 	restart = fn(timer);
+	trace_hrtimer_expire_exit(timer);
 	spin_lock(&cpu_base->lock);
 
 	/*
@@ -1328,7 +1296,7 @@ void hrtimer_interrupt(struct clock_event_device *dev)
 				break;
 			}
 
-			__run_hrtimer(timer);
+			__run_hrtimer(timer, &basenow);
 		}
 		base++;
 	}
@@ -1450,7 +1418,7 @@ void hrtimer_run_queues(void)
 					hrtimer_get_expires_tv64(timer))
 				break;
 
-			__run_hrtimer(timer);
+			__run_hrtimer(timer, &base->softirq_time);
 		}
 		spin_unlock(&cpu_base->lock);
 	}
@@ -1477,6 +1445,7 @@ void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *task)
 	sl->timer.function = hrtimer_wakeup;
 	sl->task = task;
 }
+EXPORT_SYMBOL_GPL(hrtimer_init_sleeper);
 
 static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode)
 {
@@ -1626,7 +1595,7 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
 	while ((node = rb_first(&old_base->active))) {
 		timer = rb_entry(node, struct hrtimer, node);
 		BUG_ON(hrtimer_callback_running(timer));
-		debug_hrtimer_deactivate(timer);
+		debug_deactivate(timer);
 
 		/*
 		 * Mark it as STATE_MIGRATE not INACTIVE otherwise the
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 13c68e7..c166019 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -222,6 +222,34 @@ int set_irq_chip_data(unsigned int irq, void *data)
 }
 EXPORT_SYMBOL(set_irq_chip_data);
 
+/**
+ *	set_irq_nested_thread - Set/Reset the IRQ_NESTED_THREAD flag of an irq
+ *
+ *	@irq:	Interrupt number
+ *	@nest:	0 to clear / 1 to set the IRQ_NESTED_THREAD flag
+ *
+ *	The IRQ_NESTED_THREAD flag indicates that on
+ *	request_threaded_irq() no separate interrupt thread should be
+ *	created for the irq as the handler are called nested in the
+ *	context of a demultiplexing interrupt handler thread.
+ */
+void set_irq_nested_thread(unsigned int irq, int nest)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+	unsigned long flags;
+
+	if (!desc)
+		return;
+
+	spin_lock_irqsave(&desc->lock, flags);
+	if (nest)
+		desc->status |= IRQ_NESTED_THREAD;
+	else
+		desc->status &= ~IRQ_NESTED_THREAD;
+	spin_unlock_irqrestore(&desc->lock, flags);
+}
+EXPORT_SYMBOL_GPL(set_irq_nested_thread);
+
 /*
  * default enable function
  */
@@ -299,6 +327,45 @@ static inline void mask_ack_irq(struct irq_desc *desc, int irq)
 	}
 }
 
+/*
+ *	handle_nested_irq - Handle a nested irq from a irq thread
+ *	@irq:	the interrupt number
+ *
+ *	Handle interrupts which are nested into a threaded interrupt
+ *	handler. The handler function is called inside the calling
+ *	threads context.
+ */
+void handle_nested_irq(unsigned int irq)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+	struct irqaction *action;
+	irqreturn_t action_ret;
+
+	might_sleep();
+
+	spin_lock_irq(&desc->lock);
+
+	kstat_incr_irqs_this_cpu(irq, desc);
+
+	action = desc->action;
+	if (unlikely(!action || (desc->status & IRQ_DISABLED)))
+		goto out_unlock;
+
+	desc->status |= IRQ_INPROGRESS;
+	spin_unlock_irq(&desc->lock);
+
+	action_ret = action->thread_fn(action->irq, action->dev_id);
+	if (!noirqdebug)
+		note_interrupt(irq, desc, action_ret);
+
+	spin_lock_irq(&desc->lock);
+	desc->status &= ~IRQ_INPROGRESS;
+
+out_unlock:
+	spin_unlock_irq(&desc->lock);
+}
+EXPORT_SYMBOL_GPL(handle_nested_irq);
+
 /**
  *	handle_simple_irq - Simple and software-decoded IRQs.
  *	@irq:	the interrupt number
@@ -382,7 +449,10 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc)
 
 	spin_lock(&desc->lock);
 	desc->status &= ~IRQ_INPROGRESS;
-	if (!(desc->status & IRQ_DISABLED) && desc->chip->unmask)
+
+	if (unlikely(desc->status & IRQ_ONESHOT))
+		desc->status |= IRQ_MASKED;
+	else if (!(desc->status & IRQ_DISABLED) && desc->chip->unmask)
 		desc->chip->unmask(irq);
 out_unlock:
 	spin_unlock(&desc->lock);
@@ -572,6 +642,7 @@ __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 		desc->chip = &dummy_irq_chip;
 	}
 
+	chip_bus_lock(irq, desc);
 	spin_lock_irqsave(&desc->lock, flags);
 
 	/* Uninstall? */
@@ -591,6 +662,7 @@ __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 		desc->chip->startup(irq);
 	}
 	spin_unlock_irqrestore(&desc->lock, flags);
+	chip_bus_sync_unlock(irq, desc);
 }
 EXPORT_SYMBOL_GPL(__set_irq_handler);
 
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 065205b..a81cf80 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -161,7 +161,7 @@ int __init early_irq_init(void)
 
 	desc = irq_desc_legacy;
 	legacy_count = ARRAY_SIZE(irq_desc_legacy);
- 	node = first_online_node;
+	node = first_online_node;
 
 	/* allocate irq_desc_ptrs array based on nr_irqs */
 	irq_desc_ptrs = kcalloc(nr_irqs, sizeof(void *), GFP_NOWAIT);
@@ -172,6 +172,9 @@ int __init early_irq_init(void)
 
 	for (i = 0; i < legacy_count; i++) {
 		desc[i].irq = i;
+#ifdef CONFIG_SMP
+		desc[i].node = node;
+#endif
 		desc[i].kstat_irqs = kstat_irqs_legacy + i * nr_cpu_ids;
 		lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
 		alloc_desc_masks(&desc[i], node, true);
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index e70ed55..1b5d742 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -44,6 +44,19 @@ extern int irq_select_affinity_usr(unsigned int irq);
 
 extern void irq_set_thread_affinity(struct irq_desc *desc);
 
+/* Inline functions for support of irq chips on slow busses */
+static inline void chip_bus_lock(unsigned int irq, struct irq_desc *desc)
+{
+	if (unlikely(desc->chip->bus_lock))
+		desc->chip->bus_lock(irq);
+}
+
+static inline void chip_bus_sync_unlock(unsigned int irq, struct irq_desc *desc)
+{
+	if (unlikely(desc->chip->bus_sync_unlock))
+		desc->chip->bus_sync_unlock(irq);
+}
+
 /*
  * Debugging printout:
  */
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 0ec9ed8..bde4c66 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -230,9 +230,11 @@ void disable_irq_nosync(unsigned int irq)
 	if (!desc)
 		return;
 
+	chip_bus_lock(irq, desc);
 	spin_lock_irqsave(&desc->lock, flags);
 	__disable_irq(desc, irq, false);
 	spin_unlock_irqrestore(&desc->lock, flags);
+	chip_bus_sync_unlock(irq, desc);
 }
 EXPORT_SYMBOL(disable_irq_nosync);
 
@@ -294,7 +296,8 @@ void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume)
  *	matches the last disable, processing of interrupts on this
  *	IRQ line is re-enabled.
  *
- *	This function may be called from IRQ context.
+ *	This function may be called from IRQ context only when
+ *	desc->chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
  */
 void enable_irq(unsigned int irq)
 {
@@ -304,9 +307,11 @@ void enable_irq(unsigned int irq)
 	if (!desc)
 		return;
 
+	chip_bus_lock(irq, desc);
 	spin_lock_irqsave(&desc->lock, flags);
 	__enable_irq(desc, irq, false);
 	spin_unlock_irqrestore(&desc->lock, flags);
+	chip_bus_sync_unlock(irq, desc);
 }
 EXPORT_SYMBOL(enable_irq);
 
@@ -436,6 +441,26 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
 	return ret;
 }
 
+/*
+ * Default primary interrupt handler for threaded interrupts. Is
+ * assigned as primary handler when request_threaded_irq is called
+ * with handler == NULL. Useful for oneshot interrupts.
+ */
+static irqreturn_t irq_default_primary_handler(int irq, void *dev_id)
+{
+	return IRQ_WAKE_THREAD;
+}
+
+/*
+ * Primary handler for nested threaded interrupts. Should never be
+ * called.
+ */
+static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)
+{
+	WARN(1, "Primary handler called for nested irq %d\n", irq);
+	return IRQ_NONE;
+}
+
 static int irq_wait_for_interrupt(struct irqaction *action)
 {
 	while (!kthread_should_stop()) {
@@ -451,6 +476,23 @@ static int irq_wait_for_interrupt(struct irqaction *action)
 	return -1;
 }
 
+/*
+ * Oneshot interrupts keep the irq line masked until the threaded
+ * handler finished. unmask if the interrupt has not been disabled and
+ * is marked MASKED.
+ */
+static void irq_finalize_oneshot(unsigned int irq, struct irq_desc *desc)
+{
+	chip_bus_lock(irq, desc);
+	spin_lock_irq(&desc->lock);
+	if (!(desc->status & IRQ_DISABLED) && (desc->status & IRQ_MASKED)) {
+		desc->status &= ~IRQ_MASKED;
+		desc->chip->unmask(irq);
+	}
+	spin_unlock_irq(&desc->lock);
+	chip_bus_sync_unlock(irq, desc);
+}
+
 #ifdef CONFIG_SMP
 /*
  * Check whether we need to change the affinity of the interrupt thread.
@@ -492,7 +534,7 @@ static int irq_thread(void *data)
 	struct sched_param param = { .sched_priority = MAX_USER_RT_PRIO/2, };
 	struct irqaction *action = data;
 	struct irq_desc *desc = irq_to_desc(action->irq);
-	int wake;
+	int wake, oneshot = desc->status & IRQ_ONESHOT;
 
 	sched_setscheduler(current, SCHED_FIFO, &param);
 	current->irqaction = action;
@@ -518,6 +560,9 @@ static int irq_thread(void *data)
 			spin_unlock_irq(&desc->lock);
 
 			action->thread_fn(action->irq, action->dev_id);
+
+			if (oneshot)
+				irq_finalize_oneshot(action->irq, desc);
 		}
 
 		wake = atomic_dec_and_test(&desc->threads_active);
@@ -565,7 +610,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 	struct irqaction *old, **old_ptr;
 	const char *old_name = NULL;
 	unsigned long flags;
-	int shared = 0;
+	int nested, shared = 0;
 	int ret;
 
 	if (!desc)
@@ -590,10 +635,32 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 		rand_initialize_irq(irq);
 	}
 
+	/* Oneshot interrupts are not allowed with shared */
+	if ((new->flags & IRQF_ONESHOT) && (new->flags & IRQF_SHARED))
+		return -EINVAL;
+
+	/*
+	 * Check whether the interrupt nests into another interrupt
+	 * thread.
+	 */
+	nested = desc->status & IRQ_NESTED_THREAD;
+	if (nested) {
+		if (!new->thread_fn)
+			return -EINVAL;
+		/*
+		 * Replace the primary handler which was provided from
+		 * the driver for non nested interrupt handling by the
+		 * dummy function which warns when called.
+		 */
+		new->handler = irq_nested_primary_handler;
+	}
+
 	/*
-	 * Threaded handler ?
+	 * Create a handler thread when a thread function is supplied
+	 * and the interrupt does not nest into another interrupt
+	 * thread.
 	 */
-	if (new->thread_fn) {
+	if (new->thread_fn && !nested) {
 		struct task_struct *t;
 
 		t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
@@ -662,9 +729,12 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 			desc->status |= IRQ_PER_CPU;
 #endif
 
-		desc->status &= ~(IRQ_AUTODETECT | IRQ_WAITING |
+		desc->status &= ~(IRQ_AUTODETECT | IRQ_WAITING | IRQ_ONESHOT |
 				  IRQ_INPROGRESS | IRQ_SPURIOUS_DISABLED);
 
+		if (new->flags & IRQF_ONESHOT)
+			desc->status |= IRQ_ONESHOT;
+
 		if (!(desc->status & IRQ_NOAUTOEN)) {
 			desc->depth = 0;
 			desc->status &= ~IRQ_DISABLED;
@@ -875,7 +945,14 @@ EXPORT_SYMBOL_GPL(remove_irq);
  */
 void free_irq(unsigned int irq, void *dev_id)
 {
+	struct irq_desc *desc = irq_to_desc(irq);
+
+	if (!desc)
+		return;
+
+	chip_bus_lock(irq, desc);
 	kfree(__free_irq(irq, dev_id));
+	chip_bus_sync_unlock(irq, desc);
 }
 EXPORT_SYMBOL(free_irq);
 
@@ -884,6 +961,8 @@ EXPORT_SYMBOL(free_irq);
  *	@irq: Interrupt line to allocate
  *	@handler: Function to be called when the IRQ occurs.
  *		  Primary handler for threaded interrupts
+ *		  If NULL and thread_fn != NULL the default
+ *		  primary handler is installed
  *	@thread_fn: Function called from the irq handler thread
  *		    If NULL, no irq thread is created
  *	@irqflags: Interrupt type flags
@@ -963,8 +1042,12 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
 
 	if (desc->status & IRQ_NOREQUEST)
 		return -EINVAL;
-	if (!handler)
-		return -EINVAL;
+
+	if (!handler) {
+		if (!thread_fn)
+			return -EINVAL;
+		handler = irq_default_primary_handler;
+	}
 
 	action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
 	if (!action)
@@ -976,7 +1059,10 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
 	action->name = devname;
 	action->dev_id = dev_id;
 
+	chip_bus_lock(irq, desc);
 	retval = __setup_irq(irq, desc, action);
+	chip_bus_sync_unlock(irq, desc);
+
 	if (retval)
 		kfree(action);
 
diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c
index 638d8be..a0bb09e 100644
--- a/kernel/irq/pm.c
+++ b/kernel/irq/pm.c
@@ -15,10 +15,10 @@
 /**
  * suspend_device_irqs - disable all currently enabled interrupt lines
  *
- * During system-wide suspend or hibernation device interrupts need to be
- * disabled at the chip level and this function is provided for this purpose.
- * It disables all interrupt lines that are enabled at the moment and sets the
- * IRQ_SUSPENDED flag for them.
+ * During system-wide suspend or hibernation device drivers need to be prevented
+ * from receiving interrupts and this function is provided for this purpose.
+ * It marks all interrupt lines in use, except for the timer ones, as disabled
+ * and sets the IRQ_SUSPENDED flag for each of them.
  */
 void suspend_device_irqs(void)
 {
diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c
index 89c7117..090c376 100644
--- a/kernel/irq/resend.c
+++ b/kernel/irq/resend.c
@@ -70,8 +70,7 @@ void check_irq_resend(struct irq_desc *desc, unsigned int irq)
 	if ((status & (IRQ_LEVEL | IRQ_PENDING | IRQ_REPLAY)) == IRQ_PENDING) {
 		desc->status = (status & ~IRQ_PENDING) | IRQ_REPLAY;
 
-		if (!desc->chip || !desc->chip->retrigger ||
-					!desc->chip->retrigger(irq)) {
+		if (!desc->chip->retrigger || !desc->chip->retrigger(irq)) {
 #ifdef CONFIG_HARDIRQS_SW_RESEND
 			/* Set it pending and activate the softirq: */
 			set_bit(irq, irqs_resend);
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index 4d56829..114e704 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -297,7 +297,6 @@ static int __init irqfixup_setup(char *str)
 
 __setup("irqfixup", irqfixup_setup);
 module_param(irqfixup, int, 0644);
-MODULE_PARM_DESC("irqfixup", "0: No fixup, 1: irqfixup mode, 2: irqpoll mode");
 
 static int __init irqpoll_setup(char *str)
 {
diff --git a/kernel/itimer.c b/kernel/itimer.c
index 58762f7..b03451e 100644
--- a/kernel/itimer.c
+++ b/kernel/itimer.c
@@ -12,6 +12,7 @@
 #include <linux/time.h>
 #include <linux/posix-timers.h>
 #include <linux/hrtimer.h>
+#include <trace/events/timer.h>
 
 #include <asm/uaccess.h>
 
@@ -41,10 +42,43 @@ static struct timeval itimer_get_remtime(struct hrtimer *timer)
 	return ktime_to_timeval(rem);
 }
 
+static void get_cpu_itimer(struct task_struct *tsk, unsigned int clock_id,
+			   struct itimerval *const value)
+{
+	cputime_t cval, cinterval;
+	struct cpu_itimer *it = &tsk->signal->it[clock_id];
+
+	spin_lock_irq(&tsk->sighand->siglock);
+
+	cval = it->expires;
+	cinterval = it->incr;
+	if (!cputime_eq(cval, cputime_zero)) {
+		struct task_cputime cputime;
+		cputime_t t;
+
+		thread_group_cputimer(tsk, &cputime);
+		if (clock_id == CPUCLOCK_PROF)
+			t = cputime_add(cputime.utime, cputime.stime);
+		else
+			/* CPUCLOCK_VIRT */
+			t = cputime.utime;
+
+		if (cputime_le(cval, t))
+			/* about to fire */
+			cval = cputime_one_jiffy;
+		else
+			cval = cputime_sub(cval, t);
+	}
+
+	spin_unlock_irq(&tsk->sighand->siglock);
+
+	cputime_to_timeval(cval, &value->it_value);
+	cputime_to_timeval(cinterval, &value->it_interval);
+}
+
 int do_getitimer(int which, struct itimerval *value)
 {
 	struct task_struct *tsk = current;
-	cputime_t cinterval, cval;
 
 	switch (which) {
 	case ITIMER_REAL:
@@ -55,44 +89,10 @@ int do_getitimer(int which, struct itimerval *value)
 		spin_unlock_irq(&tsk->sighand->siglock);
 		break;
 	case ITIMER_VIRTUAL:
-		spin_lock_irq(&tsk->sighand->siglock);
-		cval = tsk->signal->it_virt_expires;
-		cinterval = tsk->signal->it_virt_incr;
-		if (!cputime_eq(cval, cputime_zero)) {
-			struct task_cputime cputime;
-			cputime_t utime;
-
-			thread_group_cputimer(tsk, &cputime);
-			utime = cputime.utime;
-			if (cputime_le(cval, utime)) { /* about to fire */
-				cval = jiffies_to_cputime(1);
-			} else {
-				cval = cputime_sub(cval, utime);
-			}
-		}
-		spin_unlock_irq(&tsk->sighand->siglock);
-		cputime_to_timeval(cval, &value->it_value);
-		cputime_to_timeval(cinterval, &value->it_interval);
+		get_cpu_itimer(tsk, CPUCLOCK_VIRT, value);
 		break;
 	case ITIMER_PROF:
-		spin_lock_irq(&tsk->sighand->siglock);
-		cval = tsk->signal->it_prof_expires;
-		cinterval = tsk->signal->it_prof_incr;
-		if (!cputime_eq(cval, cputime_zero)) {
-			struct task_cputime times;
-			cputime_t ptime;
-
-			thread_group_cputimer(tsk, &times);
-			ptime = cputime_add(times.utime, times.stime);
-			if (cputime_le(cval, ptime)) { /* about to fire */
-				cval = jiffies_to_cputime(1);
-			} else {
-				cval = cputime_sub(cval, ptime);
-			}
-		}
-		spin_unlock_irq(&tsk->sighand->siglock);
-		cputime_to_timeval(cval, &value->it_value);
-		cputime_to_timeval(cinterval, &value->it_interval);
+		get_cpu_itimer(tsk, CPUCLOCK_PROF, value);
 		break;
 	default:
 		return(-EINVAL);
@@ -123,11 +123,62 @@ enum hrtimer_restart it_real_fn(struct hrtimer *timer)
 	struct signal_struct *sig =
 		container_of(timer, struct signal_struct, real_timer);
 
+	trace_itimer_expire(ITIMER_REAL, sig->leader_pid, 0);
 	kill_pid_info(SIGALRM, SEND_SIG_PRIV, sig->leader_pid);
 
 	return HRTIMER_NORESTART;
 }
 
+static inline u32 cputime_sub_ns(cputime_t ct, s64 real_ns)
+{
+	struct timespec ts;
+	s64 cpu_ns;
+
+	cputime_to_timespec(ct, &ts);
+	cpu_ns = timespec_to_ns(&ts);
+
+	return (cpu_ns <= real_ns) ? 0 : cpu_ns - real_ns;
+}
+
+static void set_cpu_itimer(struct task_struct *tsk, unsigned int clock_id,
+			   const struct itimerval *const value,
+			   struct itimerval *const ovalue)
+{
+	cputime_t cval, nval, cinterval, ninterval;
+	s64 ns_ninterval, ns_nval;
+	struct cpu_itimer *it = &tsk->signal->it[clock_id];
+
+	nval = timeval_to_cputime(&value->it_value);
+	ns_nval = timeval_to_ns(&value->it_value);
+	ninterval = timeval_to_cputime(&value->it_interval);
+	ns_ninterval = timeval_to_ns(&value->it_interval);
+
+	it->incr_error = cputime_sub_ns(ninterval, ns_ninterval);
+	it->error = cputime_sub_ns(nval, ns_nval);
+
+	spin_lock_irq(&tsk->sighand->siglock);
+
+	cval = it->expires;
+	cinterval = it->incr;
+	if (!cputime_eq(cval, cputime_zero) ||
+	    !cputime_eq(nval, cputime_zero)) {
+		if (cputime_gt(nval, cputime_zero))
+			nval = cputime_add(nval, cputime_one_jiffy);
+		set_process_cpu_timer(tsk, clock_id, &nval, &cval);
+	}
+	it->expires = nval;
+	it->incr = ninterval;
+	trace_itimer_state(clock_id == CPUCLOCK_VIRT ?
+			   ITIMER_VIRTUAL : ITIMER_PROF, value, nval);
+
+	spin_unlock_irq(&tsk->sighand->siglock);
+
+	if (ovalue) {
+		cputime_to_timeval(cval, &ovalue->it_value);
+		cputime_to_timeval(cinterval, &ovalue->it_interval);
+	}
+}
+
 /*
  * Returns true if the timeval is in canonical form
  */
@@ -139,7 +190,6 @@ int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue)
 	struct task_struct *tsk = current;
 	struct hrtimer *timer;
 	ktime_t expires;
-	cputime_t cval, cinterval, nval, ninterval;
 
 	/*
 	 * Validate the timevals in value.
@@ -171,51 +221,14 @@ again:
 		} else
 			tsk->signal->it_real_incr.tv64 = 0;
 
+		trace_itimer_state(ITIMER_REAL, value, 0);
 		spin_unlock_irq(&tsk->sighand->siglock);
 		break;
 	case ITIMER_VIRTUAL:
-		nval = timeval_to_cputime(&value->it_value);
-		ninterval = timeval_to_cputime(&value->it_interval);
-		spin_lock_irq(&tsk->sighand->siglock);
-		cval = tsk->signal->it_virt_expires;
-		cinterval = tsk->signal->it_virt_incr;
-		if (!cputime_eq(cval, cputime_zero) ||
-		    !cputime_eq(nval, cputime_zero)) {
-			if (cputime_gt(nval, cputime_zero))
-				nval = cputime_add(nval,
-						   jiffies_to_cputime(1));
-			set_process_cpu_timer(tsk, CPUCLOCK_VIRT,
-					      &nval, &cval);
-		}
-		tsk->signal->it_virt_expires = nval;
-		tsk->signal->it_virt_incr = ninterval;
-		spin_unlock_irq(&tsk->sighand->siglock);
-		if (ovalue) {
-			cputime_to_timeval(cval, &ovalue->it_value);
-			cputime_to_timeval(cinterval, &ovalue->it_interval);
-		}
+		set_cpu_itimer(tsk, CPUCLOCK_VIRT, value, ovalue);
 		break;
 	case ITIMER_PROF:
-		nval = timeval_to_cputime(&value->it_value);
-		ninterval = timeval_to_cputime(&value->it_interval);
-		spin_lock_irq(&tsk->sighand->siglock);
-		cval = tsk->signal->it_prof_expires;
-		cinterval = tsk->signal->it_prof_incr;
-		if (!cputime_eq(cval, cputime_zero) ||
-		    !cputime_eq(nval, cputime_zero)) {
-			if (cputime_gt(nval, cputime_zero))
-				nval = cputime_add(nval,
-						   jiffies_to_cputime(1));
-			set_process_cpu_timer(tsk, CPUCLOCK_PROF,
-					      &nval, &cval);
-		}
-		tsk->signal->it_prof_expires = nval;
-		tsk->signal->it_prof_incr = ninterval;
-		spin_unlock_irq(&tsk->sighand->siglock);
-		if (ovalue) {
-			cputime_to_timeval(cval, &ovalue->it_value);
-			cputime_to_timeval(cinterval, &ovalue->it_interval);
-		}
+		set_cpu_itimer(tsk, CPUCLOCK_PROF, value, ovalue);
 		break;
 	default:
 		return -EINVAL;
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 3a29dbe..8b6b8b6 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -59,7 +59,8 @@ static inline int is_kernel_inittext(unsigned long addr)
 
 static inline int is_kernel_text(unsigned long addr)
 {
-	if (addr >= (unsigned long)_stext && addr <= (unsigned long)_etext)
+	if ((addr >= (unsigned long)_stext && addr <= (unsigned long)_etext) ||
+	    arch_is_kernel_text(addr))
 		return 1;
 	return in_gate_area_no_task(addr);
 }
diff --git a/kernel/kfifo.c b/kernel/kfifo.c
index 26539e3..3765ff3 100644
--- a/kernel/kfifo.c
+++ b/kernel/kfifo.c
@@ -117,7 +117,7 @@ EXPORT_SYMBOL(kfifo_free);
  * writer, you don't need extra locking to use these functions.
  */
 unsigned int __kfifo_put(struct kfifo *fifo,
-			 unsigned char *buffer, unsigned int len)
+			const unsigned char *buffer, unsigned int len)
 {
 	unsigned int l;
 
diff --git a/kernel/kmod.c b/kernel/kmod.c
index a922808..689d20f 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -80,6 +80,10 @@ int __request_module(bool wait, const char *fmt, ...)
 #define MAX_KMOD_CONCURRENT 50	/* Completely arbitrary value - KAO */
 	static int kmod_loop_msg;
 
+	ret = security_kernel_module_request();
+	if (ret)
+		return ret;
+
 	va_start(args, fmt);
 	ret = vsnprintf(module_name, MODULE_NAME_LEN, fmt, args);
 	va_end(args);
@@ -139,6 +143,7 @@ struct subprocess_info {
 static int ____call_usermodehelper(void *data)
 {
 	struct subprocess_info *sub_info = data;
+	enum umh_wait wait = sub_info->wait;
 	int retval;
 
 	BUG_ON(atomic_read(&sub_info->cred->usage) != 1);
@@ -180,10 +185,14 @@ static int ____call_usermodehelper(void *data)
 	 */
 	set_user_nice(current, 0);
 
+	if (wait == UMH_WAIT_EXEC)
+		complete(sub_info->complete);
+
 	retval = kernel_execve(sub_info->path, sub_info->argv, sub_info->envp);
 
 	/* Exec failed? */
-	sub_info->retval = retval;
+	if (wait != UMH_WAIT_EXEC)
+		sub_info->retval = retval;
 	do_exit(0);
 }
 
@@ -262,16 +271,14 @@ static void __call_usermodehelper(struct work_struct *work)
 
 	switch (wait) {
 	case UMH_NO_WAIT:
+	case UMH_WAIT_EXEC:
 		break;
 
 	case UMH_WAIT_PROC:
 		if (pid > 0)
 			break;
 		sub_info->retval = pid;
-		/* FALLTHROUGH */
-
-	case UMH_WAIT_EXEC:
-		complete(sub_info->complete);
+		break;
 	}
 }
 
@@ -466,6 +473,7 @@ int call_usermodehelper_exec(struct subprocess_info *sub_info,
 	int retval = 0;
 
 	BUG_ON(atomic_read(&sub_info->cred->usage) != 1);
+	validate_creds(sub_info->cred);
 
 	helper_lock();
 	if (sub_info->path[0] == '\0')
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index b946761..b466afa 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1349,7 +1349,7 @@ static int __kprobes show_kprobe_addr(struct seq_file *pi, void *v)
 	return 0;
 }
 
-static struct seq_operations kprobes_seq_ops = {
+static const struct seq_operations kprobes_seq_ops = {
 	.start = kprobe_seq_start,
 	.next  = kprobe_seq_next,
 	.stop  = kprobe_seq_stop,
diff --git a/kernel/kthread.c b/kernel/kthread.c
index eb8751a..5fe7099 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -16,8 +16,6 @@
 #include <linux/mutex.h>
 #include <trace/events/sched.h>
 
-#define KTHREAD_NICE_LEVEL (-5)
-
 static DEFINE_SPINLOCK(kthread_create_lock);
 static LIST_HEAD(kthread_create_list);
 struct task_struct *kthreadd_task;
@@ -145,7 +143,6 @@ struct task_struct *kthread_create(int (*threadfn)(void *data),
 		 * The kernel thread should not inherit these properties.
 		 */
 		sched_setscheduler_nocheck(create.result, SCHED_NORMAL, &param);
-		set_user_nice(create.result, KTHREAD_NICE_LEVEL);
 		set_cpus_allowed_ptr(create.result, cpu_all_mask);
 	}
 	return create.result;
@@ -221,7 +218,6 @@ int kthreadd(void *unused)
 	/* Setup a clean context for our children to inherit. */
 	set_task_comm(tsk, "kthreadd");
 	ignore_signals(tsk);
-	set_user_nice(tsk, KTHREAD_NICE_LEVEL);
 	set_cpus_allowed_ptr(tsk, cpu_all_mask);
 	set_mems_allowed(node_possible_map);
 
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 8bbeef9..3815ac1d 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -42,6 +42,7 @@
 #include <linux/hash.h>
 #include <linux/ftrace.h>
 #include <linux/stringify.h>
+#include <linux/bitops.h>
 
 #include <asm/sections.h>
 
@@ -366,11 +367,21 @@ static int save_trace(struct stack_trace *trace)
 
 	save_stack_trace(trace);
 
+	/*
+	 * Some daft arches put -1 at the end to indicate its a full trace.
+	 *
+	 * <rant> this is buggy anyway, since it takes a whole extra entry so a
+	 * complete trace that maxes out the entries provided will be reported
+	 * as incomplete, friggin useless </rant>
+	 */
+	if (trace->entries[trace->nr_entries-1] == ULONG_MAX)
+		trace->nr_entries--;
+
 	trace->max_entries = trace->nr_entries;
 
 	nr_stack_trace_entries += trace->nr_entries;
 
-	if (nr_stack_trace_entries == MAX_STACK_TRACE_ENTRIES) {
+	if (nr_stack_trace_entries >= MAX_STACK_TRACE_ENTRIES-1) {
 		if (!debug_locks_off_graph_unlock())
 			return 0;
 
@@ -388,20 +399,6 @@ unsigned int nr_hardirq_chains;
 unsigned int nr_softirq_chains;
 unsigned int nr_process_chains;
 unsigned int max_lockdep_depth;
-unsigned int max_recursion_depth;
-
-static unsigned int lockdep_dependency_gen_id;
-
-static bool lockdep_dependency_visit(struct lock_class *source,
-				     unsigned int depth)
-{
-	if (!depth)
-		lockdep_dependency_gen_id++;
-	if (source->dep_gen_id == lockdep_dependency_gen_id)
-		return true;
-	source->dep_gen_id = lockdep_dependency_gen_id;
-	return false;
-}
 
 #ifdef CONFIG_DEBUG_LOCKDEP
 /*
@@ -431,11 +428,8 @@ atomic_t redundant_softirqs_on;
 atomic_t redundant_softirqs_off;
 atomic_t nr_unused_locks;
 atomic_t nr_cyclic_checks;
-atomic_t nr_cyclic_check_recursions;
 atomic_t nr_find_usage_forwards_checks;
-atomic_t nr_find_usage_forwards_recursions;
 atomic_t nr_find_usage_backwards_checks;
-atomic_t nr_find_usage_backwards_recursions;
 #endif
 
 /*
@@ -551,58 +545,6 @@ static void lockdep_print_held_locks(struct task_struct *curr)
 	}
 }
 
-static void print_lock_class_header(struct lock_class *class, int depth)
-{
-	int bit;
-
-	printk("%*s->", depth, "");
-	print_lock_name(class);
-	printk(" ops: %lu", class->ops);
-	printk(" {\n");
-
-	for (bit = 0; bit < LOCK_USAGE_STATES; bit++) {
-		if (class->usage_mask & (1 << bit)) {
-			int len = depth;
-
-			len += printk("%*s   %s", depth, "", usage_str[bit]);
-			len += printk(" at:\n");
-			print_stack_trace(class->usage_traces + bit, len);
-		}
-	}
-	printk("%*s }\n", depth, "");
-
-	printk("%*s ... key      at: ",depth,"");
-	print_ip_sym((unsigned long)class->key);
-}
-
-/*
- * printk all lock dependencies starting at <entry>:
- */
-static void __used
-print_lock_dependencies(struct lock_class *class, int depth)
-{
-	struct lock_list *entry;
-
-	if (lockdep_dependency_visit(class, depth))
-		return;
-
-	if (DEBUG_LOCKS_WARN_ON(depth >= 20))
-		return;
-
-	print_lock_class_header(class, depth);
-
-	list_for_each_entry(entry, &class->locks_after, entry) {
-		if (DEBUG_LOCKS_WARN_ON(!entry->class))
-			return;
-
-		print_lock_dependencies(entry->class, depth + 1);
-
-		printk("%*s ... acquired at:\n",depth,"");
-		print_stack_trace(&entry->trace, 2);
-		printk("\n");
-	}
-}
-
 static void print_kernel_version(void)
 {
 	printk("%s %.*s\n", init_utsname()->release,
@@ -636,6 +578,9 @@ static int static_obj(void *obj)
 	if ((addr >= start) && (addr < end))
 		return 1;
 
+	if (arch_is_kernel_data(addr))
+		return 1;
+
 #ifdef CONFIG_SMP
 	/*
 	 * percpu var?
@@ -898,22 +843,203 @@ static int add_lock_to_list(struct lock_class *class, struct lock_class *this,
 }
 
 /*
+ * For good efficiency of modular, we use power of 2
+ */
+#define MAX_CIRCULAR_QUEUE_SIZE		4096UL
+#define CQ_MASK				(MAX_CIRCULAR_QUEUE_SIZE-1)
+
+/*
+ * The circular_queue and helpers is used to implement the
+ * breadth-first search(BFS)algorithem, by which we can build
+ * the shortest path from the next lock to be acquired to the
+ * previous held lock if there is a circular between them.
+ */
+struct circular_queue {
+	unsigned long element[MAX_CIRCULAR_QUEUE_SIZE];
+	unsigned int  front, rear;
+};
+
+static struct circular_queue lock_cq;
+
+unsigned int max_bfs_queue_depth;
+
+static unsigned int lockdep_dependency_gen_id;
+
+static inline void __cq_init(struct circular_queue *cq)
+{
+	cq->front = cq->rear = 0;
+	lockdep_dependency_gen_id++;
+}
+
+static inline int __cq_empty(struct circular_queue *cq)
+{
+	return (cq->front == cq->rear);
+}
+
+static inline int __cq_full(struct circular_queue *cq)
+{
+	return ((cq->rear + 1) & CQ_MASK) == cq->front;
+}
+
+static inline int __cq_enqueue(struct circular_queue *cq, unsigned long elem)
+{
+	if (__cq_full(cq))
+		return -1;
+
+	cq->element[cq->rear] = elem;
+	cq->rear = (cq->rear + 1) & CQ_MASK;
+	return 0;
+}
+
+static inline int __cq_dequeue(struct circular_queue *cq, unsigned long *elem)
+{
+	if (__cq_empty(cq))
+		return -1;
+
+	*elem = cq->element[cq->front];
+	cq->front = (cq->front + 1) & CQ_MASK;
+	return 0;
+}
+
+static inline unsigned int  __cq_get_elem_count(struct circular_queue *cq)
+{
+	return (cq->rear - cq->front) & CQ_MASK;
+}
+
+static inline void mark_lock_accessed(struct lock_list *lock,
+					struct lock_list *parent)
+{
+	unsigned long nr;
+
+	nr = lock - list_entries;
+	WARN_ON(nr >= nr_list_entries);
+	lock->parent = parent;
+	lock->class->dep_gen_id = lockdep_dependency_gen_id;
+}
+
+static inline unsigned long lock_accessed(struct lock_list *lock)
+{
+	unsigned long nr;
+
+	nr = lock - list_entries;
+	WARN_ON(nr >= nr_list_entries);
+	return lock->class->dep_gen_id == lockdep_dependency_gen_id;
+}
+
+static inline struct lock_list *get_lock_parent(struct lock_list *child)
+{
+	return child->parent;
+}
+
+static inline int get_lock_depth(struct lock_list *child)
+{
+	int depth = 0;
+	struct lock_list *parent;
+
+	while ((parent = get_lock_parent(child))) {
+		child = parent;
+		depth++;
+	}
+	return depth;
+}
+
+static int __bfs(struct lock_list *source_entry,
+		 void *data,
+		 int (*match)(struct lock_list *entry, void *data),
+		 struct lock_list **target_entry,
+		 int forward)
+{
+	struct lock_list *entry;
+	struct list_head *head;
+	struct circular_queue *cq = &lock_cq;
+	int ret = 1;
+
+	if (match(source_entry, data)) {
+		*target_entry = source_entry;
+		ret = 0;
+		goto exit;
+	}
+
+	if (forward)
+		head = &source_entry->class->locks_after;
+	else
+		head = &source_entry->class->locks_before;
+
+	if (list_empty(head))
+		goto exit;
+
+	__cq_init(cq);
+	__cq_enqueue(cq, (unsigned long)source_entry);
+
+	while (!__cq_empty(cq)) {
+		struct lock_list *lock;
+
+		__cq_dequeue(cq, (unsigned long *)&lock);
+
+		if (!lock->class) {
+			ret = -2;
+			goto exit;
+		}
+
+		if (forward)
+			head = &lock->class->locks_after;
+		else
+			head = &lock->class->locks_before;
+
+		list_for_each_entry(entry, head, entry) {
+			if (!lock_accessed(entry)) {
+				unsigned int cq_depth;
+				mark_lock_accessed(entry, lock);
+				if (match(entry, data)) {
+					*target_entry = entry;
+					ret = 0;
+					goto exit;
+				}
+
+				if (__cq_enqueue(cq, (unsigned long)entry)) {
+					ret = -1;
+					goto exit;
+				}
+				cq_depth = __cq_get_elem_count(cq);
+				if (max_bfs_queue_depth < cq_depth)
+					max_bfs_queue_depth = cq_depth;
+			}
+		}
+	}
+exit:
+	return ret;
+}
+
+static inline int __bfs_forwards(struct lock_list *src_entry,
+			void *data,
+			int (*match)(struct lock_list *entry, void *data),
+			struct lock_list **target_entry)
+{
+	return __bfs(src_entry, data, match, target_entry, 1);
+
+}
+
+static inline int __bfs_backwards(struct lock_list *src_entry,
+			void *data,
+			int (*match)(struct lock_list *entry, void *data),
+			struct lock_list **target_entry)
+{
+	return __bfs(src_entry, data, match, target_entry, 0);
+
+}
+
+/*
  * Recursive, forwards-direction lock-dependency checking, used for
  * both noncyclic checking and for hardirq-unsafe/softirq-unsafe
  * checking.
- *
- * (to keep the stackframe of the recursive functions small we
- *  use these global variables, and we also mark various helper
- *  functions as noinline.)
  */
-static struct held_lock *check_source, *check_target;
 
 /*
  * Print a dependency chain entry (this is only done when a deadlock
  * has been detected):
  */
 static noinline int
-print_circular_bug_entry(struct lock_list *target, unsigned int depth)
+print_circular_bug_entry(struct lock_list *target, int depth)
 {
 	if (debug_locks_silent)
 		return 0;
@@ -930,11 +1056,13 @@ print_circular_bug_entry(struct lock_list *target, unsigned int depth)
  * header first:
  */
 static noinline int
-print_circular_bug_header(struct lock_list *entry, unsigned int depth)
+print_circular_bug_header(struct lock_list *entry, unsigned int depth,
+			struct held_lock *check_src,
+			struct held_lock *check_tgt)
 {
 	struct task_struct *curr = current;
 
-	if (!debug_locks_off_graph_unlock() || debug_locks_silent)
+	if (debug_locks_silent)
 		return 0;
 
 	printk("\n=======================================================\n");
@@ -943,9 +1071,9 @@ print_circular_bug_header(struct lock_list *entry, unsigned int depth)
 	printk(  "-------------------------------------------------------\n");
 	printk("%s/%d is trying to acquire lock:\n",
 		curr->comm, task_pid_nr(curr));
-	print_lock(check_source);
+	print_lock(check_src);
 	printk("\nbut task is already holding lock:\n");
-	print_lock(check_target);
+	print_lock(check_tgt);
 	printk("\nwhich lock already depends on the new lock.\n\n");
 	printk("\nthe existing dependency chain (in reverse order) is:\n");
 
@@ -954,19 +1082,36 @@ print_circular_bug_header(struct lock_list *entry, unsigned int depth)
 	return 0;
 }
 
-static noinline int print_circular_bug_tail(void)
+static inline int class_equal(struct lock_list *entry, void *data)
+{
+	return entry->class == data;
+}
+
+static noinline int print_circular_bug(struct lock_list *this,
+				struct lock_list *target,
+				struct held_lock *check_src,
+				struct held_lock *check_tgt)
 {
 	struct task_struct *curr = current;
-	struct lock_list this;
+	struct lock_list *parent;
+	int depth;
 
-	if (debug_locks_silent)
+	if (!debug_locks_off_graph_unlock() || debug_locks_silent)
 		return 0;
 
-	this.class = hlock_class(check_source);
-	if (!save_trace(&this.trace))
+	if (!save_trace(&this->trace))
 		return 0;
 
-	print_circular_bug_entry(&this, 0);
+	depth = get_lock_depth(target);
+
+	print_circular_bug_header(target, depth, check_src, check_tgt);
+
+	parent = get_lock_parent(target);
+
+	while (parent) {
+		print_circular_bug_entry(parent, --depth);
+		parent = get_lock_parent(parent);
+	}
 
 	printk("\nother info that might help us debug this:\n\n");
 	lockdep_print_held_locks(curr);
@@ -977,73 +1122,69 @@ static noinline int print_circular_bug_tail(void)
 	return 0;
 }
 
-#define RECURSION_LIMIT 40
-
-static int noinline print_infinite_recursion_bug(void)
+static noinline int print_bfs_bug(int ret)
 {
 	if (!debug_locks_off_graph_unlock())
 		return 0;
 
-	WARN_ON(1);
+	WARN(1, "lockdep bfs error:%d\n", ret);
 
 	return 0;
 }
 
-unsigned long __lockdep_count_forward_deps(struct lock_class *class,
-					   unsigned int depth)
+static int noop_count(struct lock_list *entry, void *data)
 {
-	struct lock_list *entry;
-	unsigned long ret = 1;
+	(*(unsigned long *)data)++;
+	return 0;
+}
 
-	if (lockdep_dependency_visit(class, depth))
-		return 0;
+unsigned long __lockdep_count_forward_deps(struct lock_list *this)
+{
+	unsigned long  count = 0;
+	struct lock_list *uninitialized_var(target_entry);
 
-	/*
-	 * Recurse this class's dependency list:
-	 */
-	list_for_each_entry(entry, &class->locks_after, entry)
-		ret += __lockdep_count_forward_deps(entry->class, depth + 1);
+	__bfs_forwards(this, (void *)&count, noop_count, &target_entry);
 
-	return ret;
+	return count;
 }
-
 unsigned long lockdep_count_forward_deps(struct lock_class *class)
 {
 	unsigned long ret, flags;
+	struct lock_list this;
+
+	this.parent = NULL;
+	this.class = class;
 
 	local_irq_save(flags);
 	__raw_spin_lock(&lockdep_lock);
-	ret = __lockdep_count_forward_deps(class, 0);
+	ret = __lockdep_count_forward_deps(&this);
 	__raw_spin_unlock(&lockdep_lock);
 	local_irq_restore(flags);
 
 	return ret;
 }
 
-unsigned long __lockdep_count_backward_deps(struct lock_class *class,
-					    unsigned int depth)
+unsigned long __lockdep_count_backward_deps(struct lock_list *this)
 {
-	struct lock_list *entry;
-	unsigned long ret = 1;
+	unsigned long  count = 0;
+	struct lock_list *uninitialized_var(target_entry);
 
-	if (lockdep_dependency_visit(class, depth))
-		return 0;
-	/*
-	 * Recurse this class's dependency list:
-	 */
-	list_for_each_entry(entry, &class->locks_before, entry)
-		ret += __lockdep_count_backward_deps(entry->class, depth + 1);
+	__bfs_backwards(this, (void *)&count, noop_count, &target_entry);
 
-	return ret;
+	return count;
 }
 
 unsigned long lockdep_count_backward_deps(struct lock_class *class)
 {
 	unsigned long ret, flags;
+	struct lock_list this;
+
+	this.parent = NULL;
+	this.class = class;
 
 	local_irq_save(flags);
 	__raw_spin_lock(&lockdep_lock);
-	ret = __lockdep_count_backward_deps(class, 0);
+	ret = __lockdep_count_backward_deps(&this);
 	__raw_spin_unlock(&lockdep_lock);
 	local_irq_restore(flags);
 
@@ -1055,29 +1196,16 @@ unsigned long lockdep_count_backward_deps(struct lock_class *class)
  * lead to <target>. Print an error and return 0 if it does.
  */
 static noinline int
-check_noncircular(struct lock_class *source, unsigned int depth)
+check_noncircular(struct lock_list *root, struct lock_class *target,
+		struct lock_list **target_entry)
 {
-	struct lock_list *entry;
+	int result;
 
-	if (lockdep_dependency_visit(source, depth))
-		return 1;
+	debug_atomic_inc(&nr_cyclic_checks);
 
-	debug_atomic_inc(&nr_cyclic_check_recursions);
-	if (depth > max_recursion_depth)
-		max_recursion_depth = depth;
-	if (depth >= RECURSION_LIMIT)
-		return print_infinite_recursion_bug();
-	/*
-	 * Check this lock's dependency list:
-	 */
-	list_for_each_entry(entry, &source->locks_after, entry) {
-		if (entry->class == hlock_class(check_target))
-			return print_circular_bug_header(entry, depth+1);
-		debug_atomic_inc(&nr_cyclic_checks);
-		if (!check_noncircular(entry->class, depth+1))
-			return print_circular_bug_entry(entry, depth+1);
-	}
-	return 1;
+	result = __bfs_forwards(root, target, class_equal, target_entry);
+
+	return result;
 }
 
 #if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_PROVE_LOCKING)
@@ -1086,103 +1214,121 @@ check_noncircular(struct lock_class *source, unsigned int depth)
  * proving that two subgraphs can be connected by a new dependency
  * without creating any illegal irq-safe -> irq-unsafe lock dependency.
  */
-static enum lock_usage_bit find_usage_bit;
-static struct lock_class *forwards_match, *backwards_match;
+
+static inline int usage_match(struct lock_list *entry, void *bit)
+{
+	return entry->class->usage_mask & (1 << (enum lock_usage_bit)bit);
+}
+
+
 
 /*
  * Find a node in the forwards-direction dependency sub-graph starting
- * at <source> that matches <find_usage_bit>.
+ * at @root->class that matches @bit.
  *
- * Return 2 if such a node exists in the subgraph, and put that node
- * into <forwards_match>.
+ * Return 0 if such a node exists in the subgraph, and put that node
+ * into *@target_entry.
  *
- * Return 1 otherwise and keep <forwards_match> unchanged.
- * Return 0 on error.
+ * Return 1 otherwise and keep *@target_entry unchanged.
+ * Return <0 on error.
  */
-static noinline int
-find_usage_forwards(struct lock_class *source, unsigned int depth)
+static int
+find_usage_forwards(struct lock_list *root, enum lock_usage_bit bit,
+			struct lock_list **target_entry)
 {
-	struct lock_list *entry;
-	int ret;
-
-	if (lockdep_dependency_visit(source, depth))
-		return 1;
-
-	if (depth > max_recursion_depth)
-		max_recursion_depth = depth;
-	if (depth >= RECURSION_LIMIT)
-		return print_infinite_recursion_bug();
+	int result;
 
 	debug_atomic_inc(&nr_find_usage_forwards_checks);
-	if (source->usage_mask & (1 << find_usage_bit)) {
-		forwards_match = source;
-		return 2;
-	}
 
-	/*
-	 * Check this lock's dependency list:
-	 */
-	list_for_each_entry(entry, &source->locks_after, entry) {
-		debug_atomic_inc(&nr_find_usage_forwards_recursions);
-		ret = find_usage_forwards(entry->class, depth+1);
-		if (ret == 2 || ret == 0)
-			return ret;
-	}
-	return 1;
+	result = __bfs_forwards(root, (void *)bit, usage_match, target_entry);
+
+	return result;
 }
 
 /*
  * Find a node in the backwards-direction dependency sub-graph starting
- * at <source> that matches <find_usage_bit>.
+ * at @root->class that matches @bit.
  *
- * Return 2 if such a node exists in the subgraph, and put that node
- * into <backwards_match>.
+ * Return 0 if such a node exists in the subgraph, and put that node
+ * into *@target_entry.
  *
- * Return 1 otherwise and keep <backwards_match> unchanged.
- * Return 0 on error.
+ * Return 1 otherwise and keep *@target_entry unchanged.
+ * Return <0 on error.
  */
-static noinline int
-find_usage_backwards(struct lock_class *source, unsigned int depth)
+static int
+find_usage_backwards(struct lock_list *root, enum lock_usage_bit bit,
+			struct lock_list **target_entry)
 {
-	struct lock_list *entry;
-	int ret;
+	int result;
 
-	if (lockdep_dependency_visit(source, depth))
-		return 1;
+	debug_atomic_inc(&nr_find_usage_backwards_checks);
 
-	if (!__raw_spin_is_locked(&lockdep_lock))
-		return DEBUG_LOCKS_WARN_ON(1);
+	result = __bfs_backwards(root, (void *)bit, usage_match, target_entry);
 
-	if (depth > max_recursion_depth)
-		max_recursion_depth = depth;
-	if (depth >= RECURSION_LIMIT)
-		return print_infinite_recursion_bug();
+	return result;
+}
 
-	debug_atomic_inc(&nr_find_usage_backwards_checks);
-	if (source->usage_mask & (1 << find_usage_bit)) {
-		backwards_match = source;
-		return 2;
-	}
+static void print_lock_class_header(struct lock_class *class, int depth)
+{
+	int bit;
 
-	if (!source && debug_locks_off_graph_unlock()) {
-		WARN_ON(1);
-		return 0;
-	}
+	printk("%*s->", depth, "");
+	print_lock_name(class);
+	printk(" ops: %lu", class->ops);
+	printk(" {\n");
 
-	/*
-	 * Check this lock's dependency list:
-	 */
-	list_for_each_entry(entry, &source->locks_before, entry) {
-		debug_atomic_inc(&nr_find_usage_backwards_recursions);
-		ret = find_usage_backwards(entry->class, depth+1);
-		if (ret == 2 || ret == 0)
-			return ret;
+	for (bit = 0; bit < LOCK_USAGE_STATES; bit++) {
+		if (class->usage_mask & (1 << bit)) {
+			int len = depth;
+
+			len += printk("%*s   %s", depth, "", usage_str[bit]);
+			len += printk(" at:\n");
+			print_stack_trace(class->usage_traces + bit, len);
+		}
 	}
-	return 1;
+	printk("%*s }\n", depth, "");
+
+	printk("%*s ... key      at: ",depth,"");
+	print_ip_sym((unsigned long)class->key);
+}
+
+/*
+ * printk the shortest lock dependencies from @start to @end in reverse order:
+ */
+static void __used
+print_shortest_lock_dependencies(struct lock_list *leaf,
+				struct lock_list *root)
+{
+	struct lock_list *entry = leaf;
+	int depth;
+
+	/*compute depth from generated tree by BFS*/
+	depth = get_lock_depth(leaf);
+
+	do {
+		print_lock_class_header(entry->class, depth);
+		printk("%*s ... acquired at:\n", depth, "");
+		print_stack_trace(&entry->trace, 2);
+		printk("\n");
+
+		if (depth == 0 && (entry != root)) {
+			printk("lockdep:%s bad BFS generated tree\n", __func__);
+			break;
+		}
+
+		entry = get_lock_parent(entry);
+		depth--;
+	} while (entry && (depth >= 0));
+
+	return;
 }
 
 static int
 print_bad_irq_dependency(struct task_struct *curr,
+			 struct lock_list *prev_root,
+			 struct lock_list *next_root,
+			 struct lock_list *backwards_entry,
+			 struct lock_list *forwards_entry,
 			 struct held_lock *prev,
 			 struct held_lock *next,
 			 enum lock_usage_bit bit1,
@@ -1215,26 +1361,32 @@ print_bad_irq_dependency(struct task_struct *curr,
 
 	printk("\nbut this new dependency connects a %s-irq-safe lock:\n",
 		irqclass);
-	print_lock_name(backwards_match);
+	print_lock_name(backwards_entry->class);
 	printk("\n... which became %s-irq-safe at:\n", irqclass);
 
-	print_stack_trace(backwards_match->usage_traces + bit1, 1);
+	print_stack_trace(backwards_entry->class->usage_traces + bit1, 1);
 
 	printk("\nto a %s-irq-unsafe lock:\n", irqclass);
-	print_lock_name(forwards_match);
+	print_lock_name(forwards_entry->class);
 	printk("\n... which became %s-irq-unsafe at:\n", irqclass);
 	printk("...");
 
-	print_stack_trace(forwards_match->usage_traces + bit2, 1);
+	print_stack_trace(forwards_entry->class->usage_traces + bit2, 1);
 
 	printk("\nother info that might help us debug this:\n\n");
 	lockdep_print_held_locks(curr);
 
-	printk("\nthe %s-irq-safe lock's dependencies:\n", irqclass);
-	print_lock_dependencies(backwards_match, 0);
+	printk("\nthe dependencies between %s-irq-safe lock", irqclass);
+	printk(" and the holding lock:\n");
+	if (!save_trace(&prev_root->trace))
+		return 0;
+	print_shortest_lock_dependencies(backwards_entry, prev_root);
 
-	printk("\nthe %s-irq-unsafe lock's dependencies:\n", irqclass);
-	print_lock_dependencies(forwards_match, 0);
+	printk("\nthe dependencies between the lock to be acquired");
+	printk(" and %s-irq-unsafe lock:\n", irqclass);
+	if (!save_trace(&next_root->trace))
+		return 0;
+	print_shortest_lock_dependencies(forwards_entry, next_root);
 
 	printk("\nstack backtrace:\n");
 	dump_stack();
@@ -1248,19 +1400,30 @@ check_usage(struct task_struct *curr, struct held_lock *prev,
 	    enum lock_usage_bit bit_forwards, const char *irqclass)
 {
 	int ret;
+	struct lock_list this, that;
+	struct lock_list *uninitialized_var(target_entry);
+	struct lock_list *uninitialized_var(target_entry1);
+
+	this.parent = NULL;
 
-	find_usage_bit = bit_backwards;
-	/* fills in <backwards_match> */
-	ret = find_usage_backwards(hlock_class(prev), 0);
-	if (!ret || ret == 1)
+	this.class = hlock_class(prev);
+	ret = find_usage_backwards(&this, bit_backwards, &target_entry);
+	if (ret < 0)
+		return print_bfs_bug(ret);
+	if (ret == 1)
 		return ret;
 
-	find_usage_bit = bit_forwards;
-	ret = find_usage_forwards(hlock_class(next), 0);
-	if (!ret || ret == 1)
+	that.parent = NULL;
+	that.class = hlock_class(next);
+	ret = find_usage_forwards(&that, bit_forwards, &target_entry1);
+	if (ret < 0)
+		return print_bfs_bug(ret);
+	if (ret == 1)
 		return ret;
-	/* ret == 2 */
-	return print_bad_irq_dependency(curr, prev, next,
+
+	return print_bad_irq_dependency(curr, &this, &that,
+			target_entry, target_entry1,
+			prev, next,
 			bit_backwards, bit_forwards, irqclass);
 }
 
@@ -1472,6 +1635,8 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev,
 {
 	struct lock_list *entry;
 	int ret;
+	struct lock_list this;
+	struct lock_list *uninitialized_var(target_entry);
 
 	/*
 	 * Prove that the new <prev> -> <next> dependency would not
@@ -1482,10 +1647,13 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev,
 	 * We are using global variables to control the recursion, to
 	 * keep the stackframe size of the recursive functions low:
 	 */
-	check_source = next;
-	check_target = prev;
-	if (!(check_noncircular(hlock_class(next), 0)))
-		return print_circular_bug_tail();
+	this.class = hlock_class(next);
+	this.parent = NULL;
+	ret = check_noncircular(&this, hlock_class(prev), &target_entry);
+	if (unlikely(!ret))
+		return print_circular_bug(&this, target_entry, next, prev);
+	else if (unlikely(ret < 0))
+		return print_bfs_bug(ret);
 
 	if (!check_prev_add_irq(curr, prev, next))
 		return 0;
@@ -1884,7 +2052,8 @@ static int mark_lock(struct task_struct *curr, struct held_lock *this,
  * print irq inversion bug:
  */
 static int
-print_irq_inversion_bug(struct task_struct *curr, struct lock_class *other,
+print_irq_inversion_bug(struct task_struct *curr,
+			struct lock_list *root, struct lock_list *other,
 			struct held_lock *this, int forwards,
 			const char *irqclass)
 {
@@ -1902,17 +2071,16 @@ print_irq_inversion_bug(struct task_struct *curr, struct lock_class *other,
 		printk("but this lock took another, %s-unsafe lock in the past:\n", irqclass);
 	else
 		printk("but this lock was taken by another, %s-safe lock in the past:\n", irqclass);
-	print_lock_name(other);
+	print_lock_name(other->class);
 	printk("\n\nand interrupts could create inverse lock ordering between them.\n\n");
 
 	printk("\nother info that might help us debug this:\n");
 	lockdep_print_held_locks(curr);
 
-	printk("\nthe first lock's dependencies:\n");
-	print_lock_dependencies(hlock_class(this), 0);
-
-	printk("\nthe second lock's dependencies:\n");
-	print_lock_dependencies(other, 0);
+	printk("\nthe shortest dependencies between 2nd lock and 1st lock:\n");
+	if (!save_trace(&root->trace))
+		return 0;
+	print_shortest_lock_dependencies(other, root);
 
 	printk("\nstack backtrace:\n");
 	dump_stack();
@@ -1929,14 +2097,19 @@ check_usage_forwards(struct task_struct *curr, struct held_lock *this,
 		     enum lock_usage_bit bit, const char *irqclass)
 {
 	int ret;
-
-	find_usage_bit = bit;
-	/* fills in <forwards_match> */
-	ret = find_usage_forwards(hlock_class(this), 0);
-	if (!ret || ret == 1)
+	struct lock_list root;
+	struct lock_list *uninitialized_var(target_entry);
+
+	root.parent = NULL;
+	root.class = hlock_class(this);
+	ret = find_usage_forwards(&root, bit, &target_entry);
+	if (ret < 0)
+		return print_bfs_bug(ret);
+	if (ret == 1)
 		return ret;
 
-	return print_irq_inversion_bug(curr, forwards_match, this, 1, irqclass);
+	return print_irq_inversion_bug(curr, &root, target_entry,
+					this, 1, irqclass);
 }
 
 /*
@@ -1948,14 +2121,19 @@ check_usage_backwards(struct task_struct *curr, struct held_lock *this,
 		      enum lock_usage_bit bit, const char *irqclass)
 {
 	int ret;
-
-	find_usage_bit = bit;
-	/* fills in <backwards_match> */
-	ret = find_usage_backwards(hlock_class(this), 0);
-	if (!ret || ret == 1)
+	struct lock_list root;
+	struct lock_list *uninitialized_var(target_entry);
+
+	root.parent = NULL;
+	root.class = hlock_class(this);
+	ret = find_usage_backwards(&root, bit, &target_entry);
+	if (ret < 0)
+		return print_bfs_bug(ret);
+	if (ret == 1)
 		return ret;
 
-	return print_irq_inversion_bug(curr, backwards_match, this, 0, irqclass);
+	return print_irq_inversion_bug(curr, &root, target_entry,
+					this, 1, irqclass);
 }
 
 void print_irqtrace_events(struct task_struct *curr)
@@ -2530,13 +2708,15 @@ EXPORT_SYMBOL_GPL(lockdep_init_map);
  */
 static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 			  int trylock, int read, int check, int hardirqs_off,
-			  struct lockdep_map *nest_lock, unsigned long ip)
+			  struct lockdep_map *nest_lock, unsigned long ip,
+			  int references)
 {
 	struct task_struct *curr = current;
 	struct lock_class *class = NULL;
 	struct held_lock *hlock;
 	unsigned int depth, id;
 	int chain_head = 0;
+	int class_idx;
 	u64 chain_key;
 
 	if (!prove_locking)
@@ -2584,10 +2764,24 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 	if (DEBUG_LOCKS_WARN_ON(depth >= MAX_LOCK_DEPTH))
 		return 0;
 
+	class_idx = class - lock_classes + 1;
+
+	if (depth) {
+		hlock = curr->held_locks + depth - 1;
+		if (hlock->class_idx == class_idx && nest_lock) {
+			if (hlock->references)
+				hlock->references++;
+			else
+				hlock->references = 2;
+
+			return 1;
+		}
+	}
+
 	hlock = curr->held_locks + depth;
 	if (DEBUG_LOCKS_WARN_ON(!class))
 		return 0;
-	hlock->class_idx = class - lock_classes + 1;
+	hlock->class_idx = class_idx;
 	hlock->acquire_ip = ip;
 	hlock->instance = lock;
 	hlock->nest_lock = nest_lock;
@@ -2595,6 +2789,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 	hlock->read = read;
 	hlock->check = check;
 	hlock->hardirqs_off = !!hardirqs_off;
+	hlock->references = references;
 #ifdef CONFIG_LOCK_STAT
 	hlock->waittime_stamp = 0;
 	hlock->holdtime_stamp = sched_clock();
@@ -2703,6 +2898,30 @@ static int check_unlock(struct task_struct *curr, struct lockdep_map *lock,
 	return 1;
 }
 
+static int match_held_lock(struct held_lock *hlock, struct lockdep_map *lock)
+{
+	if (hlock->instance == lock)
+		return 1;
+
+	if (hlock->references) {
+		struct lock_class *class = lock->class_cache;
+
+		if (!class)
+			class = look_up_lock_class(lock, 0);
+
+		if (DEBUG_LOCKS_WARN_ON(!class))
+			return 0;
+
+		if (DEBUG_LOCKS_WARN_ON(!hlock->nest_lock))
+			return 0;
+
+		if (hlock->class_idx == class - lock_classes + 1)
+			return 1;
+	}
+
+	return 0;
+}
+
 static int
 __lock_set_class(struct lockdep_map *lock, const char *name,
 		 struct lock_class_key *key, unsigned int subclass,
@@ -2726,7 +2945,7 @@ __lock_set_class(struct lockdep_map *lock, const char *name,
 		 */
 		if (prev_hlock && prev_hlock->irq_context != hlock->irq_context)
 			break;
-		if (hlock->instance == lock)
+		if (match_held_lock(hlock, lock))
 			goto found_it;
 		prev_hlock = hlock;
 	}
@@ -2745,7 +2964,8 @@ found_it:
 		if (!__lock_acquire(hlock->instance,
 			hlock_class(hlock)->subclass, hlock->trylock,
 				hlock->read, hlock->check, hlock->hardirqs_off,
-				hlock->nest_lock, hlock->acquire_ip))
+				hlock->nest_lock, hlock->acquire_ip,
+				hlock->references))
 			return 0;
 	}
 
@@ -2784,20 +3004,34 @@ lock_release_non_nested(struct task_struct *curr,
 		 */
 		if (prev_hlock && prev_hlock->irq_context != hlock->irq_context)
 			break;
-		if (hlock->instance == lock)
+		if (match_held_lock(hlock, lock))
 			goto found_it;
 		prev_hlock = hlock;
 	}
 	return print_unlock_inbalance_bug(curr, lock, ip);
 
 found_it:
-	lock_release_holdtime(hlock);
+	if (hlock->instance == lock)
+		lock_release_holdtime(hlock);
+
+	if (hlock->references) {
+		hlock->references--;
+		if (hlock->references) {
+			/*
+			 * We had, and after removing one, still have
+			 * references, the current lock stack is still
+			 * valid. We're done!
+			 */
+			return 1;
+		}
+	}
 
 	/*
 	 * We have the right lock to unlock, 'hlock' points to it.
 	 * Now we remove it from the stack, and add back the other
 	 * entries (if any), recalculating the hash along the way:
 	 */
+
 	curr->lockdep_depth = i;
 	curr->curr_chain_key = hlock->prev_chain_key;
 
@@ -2806,7 +3040,8 @@ found_it:
 		if (!__lock_acquire(hlock->instance,
 			hlock_class(hlock)->subclass, hlock->trylock,
 				hlock->read, hlock->check, hlock->hardirqs_off,
-				hlock->nest_lock, hlock->acquire_ip))
+				hlock->nest_lock, hlock->acquire_ip,
+				hlock->references))
 			return 0;
 	}
 
@@ -2836,7 +3071,7 @@ static int lock_release_nested(struct task_struct *curr,
 	/*
 	 * Is the unlock non-nested:
 	 */
-	if (hlock->instance != lock)
+	if (hlock->instance != lock || hlock->references)
 		return lock_release_non_nested(curr, lock, ip);
 	curr->lockdep_depth--;
 
@@ -2881,6 +3116,21 @@ __lock_release(struct lockdep_map *lock, int nested, unsigned long ip)
 	check_chain_key(curr);
 }
 
+static int __lock_is_held(struct lockdep_map *lock)
+{
+	struct task_struct *curr = current;
+	int i;
+
+	for (i = 0; i < curr->lockdep_depth; i++) {
+		struct held_lock *hlock = curr->held_locks + i;
+
+		if (match_held_lock(hlock, lock))
+			return 1;
+	}
+
+	return 0;
+}
+
 /*
  * Check whether we follow the irq-flags state precisely:
  */
@@ -2957,7 +3207,7 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 
 	current->lockdep_recursion = 1;
 	__lock_acquire(lock, subclass, trylock, read, check,
-		       irqs_disabled_flags(flags), nest_lock, ip);
+		       irqs_disabled_flags(flags), nest_lock, ip, 0);
 	current->lockdep_recursion = 0;
 	raw_local_irq_restore(flags);
 }
@@ -2982,6 +3232,26 @@ void lock_release(struct lockdep_map *lock, int nested,
 }
 EXPORT_SYMBOL_GPL(lock_release);
 
+int lock_is_held(struct lockdep_map *lock)
+{
+	unsigned long flags;
+	int ret = 0;
+
+	if (unlikely(current->lockdep_recursion))
+		return ret;
+
+	raw_local_irq_save(flags);
+	check_flags(flags);
+
+	current->lockdep_recursion = 1;
+	ret = __lock_is_held(lock);
+	current->lockdep_recursion = 0;
+	raw_local_irq_restore(flags);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(lock_is_held);
+
 void lockdep_set_current_reclaim_state(gfp_t gfp_mask)
 {
 	current->lockdep_reclaim_gfp = gfp_mask;
@@ -3041,7 +3311,7 @@ __lock_contended(struct lockdep_map *lock, unsigned long ip)
 		 */
 		if (prev_hlock && prev_hlock->irq_context != hlock->irq_context)
 			break;
-		if (hlock->instance == lock)
+		if (match_held_lock(hlock, lock))
 			goto found_it;
 		prev_hlock = hlock;
 	}
@@ -3049,6 +3319,9 @@ __lock_contended(struct lockdep_map *lock, unsigned long ip)
 	return;
 
 found_it:
+	if (hlock->instance != lock)
+		return;
+
 	hlock->waittime_stamp = sched_clock();
 
 	contention_point = lock_point(hlock_class(hlock)->contention_point, ip);
@@ -3088,7 +3361,7 @@ __lock_acquired(struct lockdep_map *lock, unsigned long ip)
 		 */
 		if (prev_hlock && prev_hlock->irq_context != hlock->irq_context)
 			break;
-		if (hlock->instance == lock)
+		if (match_held_lock(hlock, lock))
 			goto found_it;
 		prev_hlock = hlock;
 	}
@@ -3096,6 +3369,9 @@ __lock_acquired(struct lockdep_map *lock, unsigned long ip)
 	return;
 
 found_it:
+	if (hlock->instance != lock)
+		return;
+
 	cpu = smp_processor_id();
 	if (hlock->waittime_stamp) {
 		now = sched_clock();
@@ -3326,7 +3602,12 @@ void __init lockdep_info(void)
 		sizeof(struct list_head) * CLASSHASH_SIZE +
 		sizeof(struct lock_list) * MAX_LOCKDEP_ENTRIES +
 		sizeof(struct lock_chain) * MAX_LOCKDEP_CHAINS +
-		sizeof(struct list_head) * CHAINHASH_SIZE) / 1024);
+		sizeof(struct list_head) * CHAINHASH_SIZE
+#ifdef CONFIG_PROVE_LOCKING
+		+ sizeof(struct circular_queue)
+#endif
+		) / 1024
+		);
 
 	printk(" per task-struct memory footprint: %lu bytes\n",
 		sizeof(struct held_lock) * MAX_LOCK_DEPTH);
diff --git a/kernel/lockdep_internals.h b/kernel/lockdep_internals.h
index 699a2ac..a2ee95a 100644
--- a/kernel/lockdep_internals.h
+++ b/kernel/lockdep_internals.h
@@ -91,6 +91,8 @@ extern unsigned int nr_process_chains;
 extern unsigned int max_lockdep_depth;
 extern unsigned int max_recursion_depth;
 
+extern unsigned int max_bfs_queue_depth;
+
 #ifdef CONFIG_PROVE_LOCKING
 extern unsigned long lockdep_count_forward_deps(struct lock_class *);
 extern unsigned long lockdep_count_backward_deps(struct lock_class *);
diff --git a/kernel/lockdep_proc.c b/kernel/lockdep_proc.c
index e94caa6..d4aba4f 100644
--- a/kernel/lockdep_proc.c
+++ b/kernel/lockdep_proc.c
@@ -25,38 +25,12 @@
 
 static void *l_next(struct seq_file *m, void *v, loff_t *pos)
 {
-	struct lock_class *class;
-
-	(*pos)++;
-
-	if (v == SEQ_START_TOKEN)
-		class = m->private;
-	else {
-		class = v;
-
-		if (class->lock_entry.next != &all_lock_classes)
-			class = list_entry(class->lock_entry.next,
-					   struct lock_class, lock_entry);
-		else
-			class = NULL;
-	}
-
-	return class;
+	return seq_list_next(v, &all_lock_classes, pos);
 }
 
 static void *l_start(struct seq_file *m, loff_t *pos)
 {
-	struct lock_class *class;
-	loff_t i = 0;
-
-	if (*pos == 0)
-		return SEQ_START_TOKEN;
-
-	list_for_each_entry(class, &all_lock_classes, lock_entry) {
-		if (++i == *pos)
-		return class;
-	}
-	return NULL;
+	return seq_list_start_head(&all_lock_classes, *pos);
 }
 
 static void l_stop(struct seq_file *m, void *v)
@@ -82,11 +56,11 @@ static void print_name(struct seq_file *m, struct lock_class *class)
 
 static int l_show(struct seq_file *m, void *v)
 {
-	struct lock_class *class = v;
+	struct lock_class *class = list_entry(v, struct lock_class, lock_entry);
 	struct lock_list *entry;
 	char usage[LOCK_USAGE_CHARS];
 
-	if (v == SEQ_START_TOKEN) {
+	if (v == &all_lock_classes) {
 		seq_printf(m, "all lock classes:\n");
 		return 0;
 	}
@@ -128,17 +102,7 @@ static const struct seq_operations lockdep_ops = {
 
 static int lockdep_open(struct inode *inode, struct file *file)
 {
-	int res = seq_open(file, &lockdep_ops);
-	if (!res) {
-		struct seq_file *m = file->private_data;
-
-		if (!list_empty(&all_lock_classes))
-			m->private = list_entry(all_lock_classes.next,
-					struct lock_class, lock_entry);
-		else
-			m->private = NULL;
-	}
-	return res;
+	return seq_open(file, &lockdep_ops);
 }
 
 static const struct file_operations proc_lockdep_operations = {
@@ -149,37 +113,23 @@ static const struct file_operations proc_lockdep_operations = {
 };
 
 #ifdef CONFIG_PROVE_LOCKING
-static void *lc_next(struct seq_file *m, void *v, loff_t *pos)
-{
-	struct lock_chain *chain;
-
-	(*pos)++;
-
-	if (v == SEQ_START_TOKEN)
-		chain = m->private;
-	else {
-		chain = v;
-
-		if (*pos < nr_lock_chains)
-			chain = lock_chains + *pos;
-		else
-			chain = NULL;
-	}
-
-	return chain;
-}
-
 static void *lc_start(struct seq_file *m, loff_t *pos)
 {
 	if (*pos == 0)
 		return SEQ_START_TOKEN;
 
-	if (*pos < nr_lock_chains)
-		return lock_chains + *pos;
+	if (*pos - 1 < nr_lock_chains)
+		return lock_chains + (*pos - 1);
 
 	return NULL;
 }
 
+static void *lc_next(struct seq_file *m, void *v, loff_t *pos)
+{
+	(*pos)++;
+	return lc_start(m, pos);
+}
+
 static void lc_stop(struct seq_file *m, void *v)
 {
 }
@@ -220,16 +170,7 @@ static const struct seq_operations lockdep_chains_ops = {
 
 static int lockdep_chains_open(struct inode *inode, struct file *file)
 {
-	int res = seq_open(file, &lockdep_chains_ops);
-	if (!res) {
-		struct seq_file *m = file->private_data;
-
-		if (nr_lock_chains)
-			m->private = lock_chains;
-		else
-			m->private = NULL;
-	}
-	return res;
+	return seq_open(file, &lockdep_chains_ops);
 }
 
 static const struct file_operations proc_lockdep_chains_operations = {
@@ -258,16 +199,10 @@ static void lockdep_stats_debug_show(struct seq_file *m)
 		debug_atomic_read(&chain_lookup_hits));
 	seq_printf(m, " cyclic checks:                 %11u\n",
 		debug_atomic_read(&nr_cyclic_checks));
-	seq_printf(m, " cyclic-check recursions:       %11u\n",
-		debug_atomic_read(&nr_cyclic_check_recursions));
 	seq_printf(m, " find-mask forwards checks:     %11u\n",
 		debug_atomic_read(&nr_find_usage_forwards_checks));
-	seq_printf(m, " find-mask forwards recursions: %11u\n",
-		debug_atomic_read(&nr_find_usage_forwards_recursions));
 	seq_printf(m, " find-mask backwards checks:    %11u\n",
 		debug_atomic_read(&nr_find_usage_backwards_checks));
-	seq_printf(m, " find-mask backwards recursions:%11u\n",
-		debug_atomic_read(&nr_find_usage_backwards_recursions));
 
 	seq_printf(m, " hardirq on events:             %11u\n", hi1);
 	seq_printf(m, " hardirq off events:            %11u\n", hi2);
@@ -409,8 +344,10 @@ static int lockdep_stats_show(struct seq_file *m, void *v)
 			nr_unused);
 	seq_printf(m, " max locking depth:             %11u\n",
 			max_lockdep_depth);
-	seq_printf(m, " max recursion depth:           %11u\n",
-			max_recursion_depth);
+#ifdef CONFIG_PROVE_LOCKING
+	seq_printf(m, " max bfs queue depth:           %11u\n",
+			max_bfs_queue_depth);
+#endif
 	lockdep_stats_debug_show(m);
 	seq_printf(m, " debug_locks:                   %11u\n",
 			debug_locks);
@@ -438,7 +375,6 @@ struct lock_stat_data {
 };
 
 struct lock_stat_seq {
-	struct lock_stat_data *iter;
 	struct lock_stat_data *iter_end;
 	struct lock_stat_data stats[MAX_LOCKDEP_KEYS];
 };
@@ -626,34 +562,22 @@ static void seq_header(struct seq_file *m)
 static void *ls_start(struct seq_file *m, loff_t *pos)
 {
 	struct lock_stat_seq *data = m->private;
+	struct lock_stat_data *iter;
 
 	if (*pos == 0)
 		return SEQ_START_TOKEN;
 
-	data->iter = data->stats + *pos;
-	if (data->iter >= data->iter_end)
-		data->iter = NULL;
+	iter = data->stats + (*pos - 1);
+	if (iter >= data->iter_end)
+		iter = NULL;
 
-	return data->iter;
+	return iter;
 }
 
 static void *ls_next(struct seq_file *m, void *v, loff_t *pos)
 {
-	struct lock_stat_seq *data = m->private;
-
 	(*pos)++;
-
-	if (v == SEQ_START_TOKEN)
-		data->iter = data->stats;
-	else {
-		data->iter = v;
-		data->iter++;
-	}
-
-	if (data->iter == data->iter_end)
-		data->iter = NULL;
-
-	return data->iter;
+	return ls_start(m, pos);
 }
 
 static void ls_stop(struct seq_file *m, void *v)
@@ -670,7 +594,7 @@ static int ls_show(struct seq_file *m, void *v)
 	return 0;
 }
 
-static struct seq_operations lockstat_ops = {
+static const struct seq_operations lockstat_ops = {
 	.start	= ls_start,
 	.next	= ls_next,
 	.stop	= ls_stop,
@@ -691,7 +615,6 @@ static int lock_stat_open(struct inode *inode, struct file *file)
 		struct lock_stat_data *iter = data->stats;
 		struct seq_file *m = file->private_data;
 
-		data->iter = iter;
 		list_for_each_entry(class, &all_lock_classes, lock_entry) {
 			iter->class = class;
 			iter->stats = lock_stats(class);
@@ -699,7 +622,7 @@ static int lock_stat_open(struct inode *inode, struct file *file)
 		}
 		data->iter_end = iter;
 
-		sort(data->stats, data->iter_end - data->iter,
+		sort(data->stats, data->iter_end - data->stats,
 				sizeof(struct lock_stat_data),
 				lock_stat_cmp, NULL);
 
@@ -734,7 +657,6 @@ static int lock_stat_release(struct inode *inode, struct file *file)
 	struct seq_file *seq = file->private_data;
 
 	vfree(seq->private);
-	seq->private = NULL;
 	return seq_release(inode, file);
 }
 
diff --git a/kernel/marker.c b/kernel/marker.c
deleted file mode 100644
index ea54f26..0000000
--- a/kernel/marker.c
+++ /dev/null
@@ -1,930 +0,0 @@
-/*
- * Copyright (C) 2007 Mathieu Desnoyers
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- */
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/types.h>
-#include <linux/jhash.h>
-#include <linux/list.h>
-#include <linux/rcupdate.h>
-#include <linux/marker.h>
-#include <linux/err.h>
-#include <linux/slab.h>
-
-extern struct marker __start___markers[];
-extern struct marker __stop___markers[];
-
-/* Set to 1 to enable marker debug output */
-static const int marker_debug;
-
-/*
- * markers_mutex nests inside module_mutex. Markers mutex protects the builtin
- * and module markers and the hash table.
- */
-static DEFINE_MUTEX(markers_mutex);
-
-/*
- * Marker hash table, containing the active markers.
- * Protected by module_mutex.
- */
-#define MARKER_HASH_BITS 6
-#define MARKER_TABLE_SIZE (1 << MARKER_HASH_BITS)
-static struct hlist_head marker_table[MARKER_TABLE_SIZE];
-
-/*
- * Note about RCU :
- * It is used to make sure every handler has finished using its private data
- * between two consecutive operation (add or remove) on a given marker.  It is
- * also used to delay the free of multiple probes array until a quiescent state
- * is reached.
- * marker entries modifications are protected by the markers_mutex.
- */
-struct marker_entry {
-	struct hlist_node hlist;
-	char *format;
-			/* Probe wrapper */
-	void (*call)(const struct marker *mdata, void *call_private, ...);
-	struct marker_probe_closure single;
-	struct marker_probe_closure *multi;
-	int refcount;	/* Number of times armed. 0 if disarmed. */
-	struct rcu_head rcu;
-	void *oldptr;
-	int rcu_pending;
-	unsigned char ptype:1;
-	unsigned char format_allocated:1;
-	char name[0];	/* Contains name'\0'format'\0' */
-};
-
-/**
- * __mark_empty_function - Empty probe callback
- * @probe_private: probe private data
- * @call_private: call site private data
- * @fmt: format string
- * @...: variable argument list
- *
- * Empty callback provided as a probe to the markers. By providing this to a
- * disabled marker, we make sure the  execution flow is always valid even
- * though the function pointer change and the marker enabling are two distinct
- * operations that modifies the execution flow of preemptible code.
- */
-notrace void __mark_empty_function(void *probe_private, void *call_private,
-	const char *fmt, va_list *args)
-{
-}
-EXPORT_SYMBOL_GPL(__mark_empty_function);
-
-/*
- * marker_probe_cb Callback that prepares the variable argument list for probes.
- * @mdata: pointer of type struct marker
- * @call_private: caller site private data
- * @...:  Variable argument list.
- *
- * Since we do not use "typical" pointer based RCU in the 1 argument case, we
- * need to put a full smp_rmb() in this branch. This is why we do not use
- * rcu_dereference() for the pointer read.
- */
-notrace void marker_probe_cb(const struct marker *mdata,
-		void *call_private, ...)
-{
-	va_list args;
-	char ptype;
-
-	/*
-	 * rcu_read_lock_sched does two things : disabling preemption to make
-	 * sure the teardown of the callbacks can be done correctly when they
-	 * are in modules and they insure RCU read coherency.
-	 */
-	rcu_read_lock_sched_notrace();
-	ptype = mdata->ptype;
-	if (likely(!ptype)) {
-		marker_probe_func *func;
-		/* Must read the ptype before ptr. They are not data dependant,
-		 * so we put an explicit smp_rmb() here. */
-		smp_rmb();
-		func = mdata->single.func;
-		/* Must read the ptr before private data. They are not data
-		 * dependant, so we put an explicit smp_rmb() here. */
-		smp_rmb();
-		va_start(args, call_private);
-		func(mdata->single.probe_private, call_private, mdata->format,
-			&args);
-		va_end(args);
-	} else {
-		struct marker_probe_closure *multi;
-		int i;
-		/*
-		 * Read mdata->ptype before mdata->multi.
-		 */
-		smp_rmb();
-		multi = mdata->multi;
-		/*
-		 * multi points to an array, therefore accessing the array
-		 * depends on reading multi. However, even in this case,
-		 * we must insure that the pointer is read _before_ the array
-		 * data. Same as rcu_dereference, but we need a full smp_rmb()
-		 * in the fast path, so put the explicit barrier here.
-		 */
-		smp_read_barrier_depends();
-		for (i = 0; multi[i].func; i++) {
-			va_start(args, call_private);
-			multi[i].func(multi[i].probe_private, call_private,
-				mdata->format, &args);
-			va_end(args);
-		}
-	}
-	rcu_read_unlock_sched_notrace();
-}
-EXPORT_SYMBOL_GPL(marker_probe_cb);
-
-/*
- * marker_probe_cb Callback that does not prepare the variable argument list.
- * @mdata: pointer of type struct marker
- * @call_private: caller site private data
- * @...:  Variable argument list.
- *
- * Should be connected to markers "MARK_NOARGS".
- */
-static notrace void marker_probe_cb_noarg(const struct marker *mdata,
-		void *call_private, ...)
-{
-	va_list args;	/* not initialized */
-	char ptype;
-
-	rcu_read_lock_sched_notrace();
-	ptype = mdata->ptype;
-	if (likely(!ptype)) {
-		marker_probe_func *func;
-		/* Must read the ptype before ptr. They are not data dependant,
-		 * so we put an explicit smp_rmb() here. */
-		smp_rmb();
-		func = mdata->single.func;
-		/* Must read the ptr before private data. They are not data
-		 * dependant, so we put an explicit smp_rmb() here. */
-		smp_rmb();
-		func(mdata->single.probe_private, call_private, mdata->format,
-			&args);
-	} else {
-		struct marker_probe_closure *multi;
-		int i;
-		/*
-		 * Read mdata->ptype before mdata->multi.
-		 */
-		smp_rmb();
-		multi = mdata->multi;
-		/*
-		 * multi points to an array, therefore accessing the array
-		 * depends on reading multi. However, even in this case,
-		 * we must insure that the pointer is read _before_ the array
-		 * data. Same as rcu_dereference, but we need a full smp_rmb()
-		 * in the fast path, so put the explicit barrier here.
-		 */
-		smp_read_barrier_depends();
-		for (i = 0; multi[i].func; i++)
-			multi[i].func(multi[i].probe_private, call_private,
-				mdata->format, &args);
-	}
-	rcu_read_unlock_sched_notrace();
-}
-
-static void free_old_closure(struct rcu_head *head)
-{
-	struct marker_entry *entry = container_of(head,
-		struct marker_entry, rcu);
-	kfree(entry->oldptr);
-	/* Make sure we free the data before setting the pending flag to 0 */
-	smp_wmb();
-	entry->rcu_pending = 0;
-}
-
-static void debug_print_probes(struct marker_entry *entry)
-{
-	int i;
-
-	if (!marker_debug)
-		return;
-
-	if (!entry->ptype) {
-		printk(KERN_DEBUG "Single probe : %p %p\n",
-			entry->single.func,
-			entry->single.probe_private);
-	} else {
-		for (i = 0; entry->multi[i].func; i++)
-			printk(KERN_DEBUG "Multi probe %d : %p %p\n", i,
-				entry->multi[i].func,
-				entry->multi[i].probe_private);
-	}
-}
-
-static struct marker_probe_closure *
-marker_entry_add_probe(struct marker_entry *entry,
-		marker_probe_func *probe, void *probe_private)
-{
-	int nr_probes = 0;
-	struct marker_probe_closure *old, *new;
-
-	WARN_ON(!probe);
-
-	debug_print_probes(entry);
-	old = entry->multi;
-	if (!entry->ptype) {
-		if (entry->single.func == probe &&
-				entry->single.probe_private == probe_private)
-			return ERR_PTR(-EBUSY);
-		if (entry->single.func == __mark_empty_function) {
-			/* 0 -> 1 probes */
-			entry->single.func = probe;
-			entry->single.probe_private = probe_private;
-			entry->refcount = 1;
-			entry->ptype = 0;
-			debug_print_probes(entry);
-			return NULL;
-		} else {
-			/* 1 -> 2 probes */
-			nr_probes = 1;
-			old = NULL;
-		}
-	} else {
-		/* (N -> N+1), (N != 0, 1) probes */
-		for (nr_probes = 0; old[nr_probes].func; nr_probes++)
-			if (old[nr_probes].func == probe
-					&& old[nr_probes].probe_private
-						== probe_private)
-				return ERR_PTR(-EBUSY);
-	}
-	/* + 2 : one for new probe, one for NULL func */
-	new = kzalloc((nr_probes + 2) * sizeof(struct marker_probe_closure),
-			GFP_KERNEL);
-	if (new == NULL)
-		return ERR_PTR(-ENOMEM);
-	if (!old)
-		new[0] = entry->single;
-	else
-		memcpy(new, old,
-			nr_probes * sizeof(struct marker_probe_closure));
-	new[nr_probes].func = probe;
-	new[nr_probes].probe_private = probe_private;
-	entry->refcount = nr_probes + 1;
-	entry->multi = new;
-	entry->ptype = 1;
-	debug_print_probes(entry);
-	return old;
-}
-
-static struct marker_probe_closure *
-marker_entry_remove_probe(struct marker_entry *entry,
-		marker_probe_func *probe, void *probe_private)
-{
-	int nr_probes = 0, nr_del = 0, i;
-	struct marker_probe_closure *old, *new;
-
-	old = entry->multi;
-
-	debug_print_probes(entry);
-	if (!entry->ptype) {
-		/* 0 -> N is an error */
-		WARN_ON(entry->single.func == __mark_empty_function);
-		/* 1 -> 0 probes */
-		WARN_ON(probe && entry->single.func != probe);
-		WARN_ON(entry->single.probe_private != probe_private);
-		entry->single.func = __mark_empty_function;
-		entry->refcount = 0;
-		entry->ptype = 0;
-		debug_print_probes(entry);
-		return NULL;
-	} else {
-		/* (N -> M), (N > 1, M >= 0) probes */
-		for (nr_probes = 0; old[nr_probes].func; nr_probes++) {
-			if ((!probe || old[nr_probes].func == probe)
-					&& old[nr_probes].probe_private
-						== probe_private)
-				nr_del++;
-		}
-	}
-
-	if (nr_probes - nr_del == 0) {
-		/* N -> 0, (N > 1) */
-		entry->single.func = __mark_empty_function;
-		entry->refcount = 0;
-		entry->ptype = 0;
-	} else if (nr_probes - nr_del == 1) {
-		/* N -> 1, (N > 1) */
-		for (i = 0; old[i].func; i++)
-			if ((probe && old[i].func != probe) ||
-					old[i].probe_private != probe_private)
-				entry->single = old[i];
-		entry->refcount = 1;
-		entry->ptype = 0;
-	} else {
-		int j = 0;
-		/* N -> M, (N > 1, M > 1) */
-		/* + 1 for NULL */
-		new = kzalloc((nr_probes - nr_del + 1)
-			* sizeof(struct marker_probe_closure), GFP_KERNEL);
-		if (new == NULL)
-			return ERR_PTR(-ENOMEM);
-		for (i = 0; old[i].func; i++)
-			if ((probe && old[i].func != probe) ||
-					old[i].probe_private != probe_private)
-				new[j++] = old[i];
-		entry->refcount = nr_probes - nr_del;
-		entry->ptype = 1;
-		entry->multi = new;
-	}
-	debug_print_probes(entry);
-	return old;
-}
-
-/*
- * Get marker if the marker is present in the marker hash table.
- * Must be called with markers_mutex held.
- * Returns NULL if not present.
- */
-static struct marker_entry *get_marker(const char *name)
-{
-	struct hlist_head *head;
-	struct hlist_node *node;
-	struct marker_entry *e;
-	u32 hash = jhash(name, strlen(name), 0);
-
-	head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
-	hlist_for_each_entry(e, node, head, hlist) {
-		if (!strcmp(name, e->name))
-			return e;
-	}
-	return NULL;
-}
-
-/*
- * Add the marker to the marker hash table. Must be called with markers_mutex
- * held.
- */
-static struct marker_entry *add_marker(const char *name, const char *format)
-{
-	struct hlist_head *head;
-	struct hlist_node *node;
-	struct marker_entry *e;
-	size_t name_len = strlen(name) + 1;
-	size_t format_len = 0;
-	u32 hash = jhash(name, name_len-1, 0);
-
-	if (format)
-		format_len = strlen(format) + 1;
-	head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
-	hlist_for_each_entry(e, node, head, hlist) {
-		if (!strcmp(name, e->name)) {
-			printk(KERN_NOTICE
-				"Marker %s busy\n", name);
-			return ERR_PTR(-EBUSY);	/* Already there */
-		}
-	}
-	/*
-	 * Using kmalloc here to allocate a variable length element. Could
-	 * cause some memory fragmentation if overused.
-	 */
-	e = kmalloc(sizeof(struct marker_entry) + name_len + format_len,
-			GFP_KERNEL);
-	if (!e)
-		return ERR_PTR(-ENOMEM);
-	memcpy(&e->name[0], name, name_len);
-	if (format) {
-		e->format = &e->name[name_len];
-		memcpy(e->format, format, format_len);
-		if (strcmp(e->format, MARK_NOARGS) == 0)
-			e->call = marker_probe_cb_noarg;
-		else
-			e->call = marker_probe_cb;
-		trace_mark(core_marker_format, "name %s format %s",
-				e->name, e->format);
-	} else {
-		e->format = NULL;
-		e->call = marker_probe_cb;
-	}
-	e->single.func = __mark_empty_function;
-	e->single.probe_private = NULL;
-	e->multi = NULL;
-	e->ptype = 0;
-	e->format_allocated = 0;
-	e->refcount = 0;
-	e->rcu_pending = 0;
-	hlist_add_head(&e->hlist, head);
-	return e;
-}
-
-/*
- * Remove the marker from the marker hash table. Must be called with mutex_lock
- * held.
- */
-static int remove_marker(const char *name)
-{
-	struct hlist_head *head;
-	struct hlist_node *node;
-	struct marker_entry *e;
-	int found = 0;
-	size_t len = strlen(name) + 1;
-	u32 hash = jhash(name, len-1, 0);
-
-	head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
-	hlist_for_each_entry(e, node, head, hlist) {
-		if (!strcmp(name, e->name)) {
-			found = 1;
-			break;
-		}
-	}
-	if (!found)
-		return -ENOENT;
-	if (e->single.func != __mark_empty_function)
-		return -EBUSY;
-	hlist_del(&e->hlist);
-	if (e->format_allocated)
-		kfree(e->format);
-	/* Make sure the call_rcu has been executed */
-	if (e->rcu_pending)
-		rcu_barrier_sched();
-	kfree(e);
-	return 0;
-}
-
-/*
- * Set the mark_entry format to the format found in the element.
- */
-static int marker_set_format(struct marker_entry *entry, const char *format)
-{
-	entry->format = kstrdup(format, GFP_KERNEL);
-	if (!entry->format)
-		return -ENOMEM;
-	entry->format_allocated = 1;
-
-	trace_mark(core_marker_format, "name %s format %s",
-			entry->name, entry->format);
-	return 0;
-}
-
-/*
- * Sets the probe callback corresponding to one marker.
- */
-static int set_marker(struct marker_entry *entry, struct marker *elem,
-		int active)
-{
-	int ret = 0;
-	WARN_ON(strcmp(entry->name, elem->name) != 0);
-
-	if (entry->format) {
-		if (strcmp(entry->format, elem->format) != 0) {
-			printk(KERN_NOTICE
-				"Format mismatch for probe %s "
-				"(%s), marker (%s)\n",
-				entry->name,
-				entry->format,
-				elem->format);
-			return -EPERM;
-		}
-	} else {
-		ret = marker_set_format(entry, elem->format);
-		if (ret)
-			return ret;
-	}
-
-	/*
-	 * probe_cb setup (statically known) is done here. It is
-	 * asynchronous with the rest of execution, therefore we only
-	 * pass from a "safe" callback (with argument) to an "unsafe"
-	 * callback (does not set arguments).
-	 */
-	elem->call = entry->call;
-	/*
-	 * Sanity check :
-	 * We only update the single probe private data when the ptr is
-	 * set to a _non_ single probe! (0 -> 1 and N -> 1, N != 1)
-	 */
-	WARN_ON(elem->single.func != __mark_empty_function
-		&& elem->single.probe_private != entry->single.probe_private
-		&& !elem->ptype);
-	elem->single.probe_private = entry->single.probe_private;
-	/*
-	 * Make sure the private data is valid when we update the
-	 * single probe ptr.
-	 */
-	smp_wmb();
-	elem->single.func = entry->single.func;
-	/*
-	 * We also make sure that the new probe callbacks array is consistent
-	 * before setting a pointer to it.
-	 */
-	rcu_assign_pointer(elem->multi, entry->multi);
-	/*
-	 * Update the function or multi probe array pointer before setting the
-	 * ptype.
-	 */
-	smp_wmb();
-	elem->ptype = entry->ptype;
-
-	if (elem->tp_name && (active ^ elem->state)) {
-		WARN_ON(!elem->tp_cb);
-		/*
-		 * It is ok to directly call the probe registration because type
-		 * checking has been done in the __trace_mark_tp() macro.
-		 */
-
-		if (active) {
-			/*
-			 * try_module_get should always succeed because we hold
-			 * lock_module() to get the tp_cb address.
-			 */
-			ret = try_module_get(__module_text_address(
-				(unsigned long)elem->tp_cb));
-			BUG_ON(!ret);
-			ret = tracepoint_probe_register_noupdate(
-				elem->tp_name,
-				elem->tp_cb);
-		} else {
-			ret = tracepoint_probe_unregister_noupdate(
-				elem->tp_name,
-				elem->tp_cb);
-			/*
-			 * tracepoint_probe_update_all() must be called
-			 * before the module containing tp_cb is unloaded.
-			 */
-			module_put(__module_text_address(
-				(unsigned long)elem->tp_cb));
-		}
-	}
-	elem->state = active;
-
-	return ret;
-}
-
-/*
- * Disable a marker and its probe callback.
- * Note: only waiting an RCU period after setting elem->call to the empty
- * function insures that the original callback is not used anymore. This insured
- * by rcu_read_lock_sched around the call site.
- */
-static void disable_marker(struct marker *elem)
-{
-	int ret;
-
-	/* leave "call" as is. It is known statically. */
-	if (elem->tp_name && elem->state) {
-		WARN_ON(!elem->tp_cb);
-		/*
-		 * It is ok to directly call the probe registration because type
-		 * checking has been done in the __trace_mark_tp() macro.
-		 */
-		ret = tracepoint_probe_unregister_noupdate(elem->tp_name,
-			elem->tp_cb);
-		WARN_ON(ret);
-		/*
-		 * tracepoint_probe_update_all() must be called
-		 * before the module containing tp_cb is unloaded.
-		 */
-		module_put(__module_text_address((unsigned long)elem->tp_cb));
-	}
-	elem->state = 0;
-	elem->single.func = __mark_empty_function;
-	/* Update the function before setting the ptype */
-	smp_wmb();
-	elem->ptype = 0;	/* single probe */
-	/*
-	 * Leave the private data and id there, because removal is racy and
-	 * should be done only after an RCU period. These are never used until
-	 * the next initialization anyway.
-	 */
-}
-
-/**
- * marker_update_probe_range - Update a probe range
- * @begin: beginning of the range
- * @end: end of the range
- *
- * Updates the probe callback corresponding to a range of markers.
- */
-void marker_update_probe_range(struct marker *begin,
-	struct marker *end)
-{
-	struct marker *iter;
-	struct marker_entry *mark_entry;
-
-	mutex_lock(&markers_mutex);
-	for (iter = begin; iter < end; iter++) {
-		mark_entry = get_marker(iter->name);
-		if (mark_entry) {
-			set_marker(mark_entry, iter, !!mark_entry->refcount);
-			/*
-			 * ignore error, continue
-			 */
-		} else {
-			disable_marker(iter);
-		}
-	}
-	mutex_unlock(&markers_mutex);
-}
-
-/*
- * Update probes, removing the faulty probes.
- *
- * Internal callback only changed before the first probe is connected to it.
- * Single probe private data can only be changed on 0 -> 1 and 2 -> 1
- * transitions.  All other transitions will leave the old private data valid.
- * This makes the non-atomicity of the callback/private data updates valid.
- *
- * "special case" updates :
- * 0 -> 1 callback
- * 1 -> 0 callback
- * 1 -> 2 callbacks
- * 2 -> 1 callbacks
- * Other updates all behave the same, just like the 2 -> 3 or 3 -> 2 updates.
- * Site effect : marker_set_format may delete the marker entry (creating a
- * replacement).
- */
-static void marker_update_probes(void)
-{
-	/* Core kernel markers */
-	marker_update_probe_range(__start___markers, __stop___markers);
-	/* Markers in modules. */
-	module_update_markers();
-	tracepoint_probe_update_all();
-}
-
-/**
- * marker_probe_register -  Connect a probe to a marker
- * @name: marker name
- * @format: format string
- * @probe: probe handler
- * @probe_private: probe private data
- *
- * private data must be a valid allocated memory address, or NULL.
- * Returns 0 if ok, error value on error.
- * The probe address must at least be aligned on the architecture pointer size.
- */
-int marker_probe_register(const char *name, const char *format,
-			marker_probe_func *probe, void *probe_private)
-{
-	struct marker_entry *entry;
-	int ret = 0;
-	struct marker_probe_closure *old;
-
-	mutex_lock(&markers_mutex);
-	entry = get_marker(name);
-	if (!entry) {
-		entry = add_marker(name, format);
-		if (IS_ERR(entry))
-			ret = PTR_ERR(entry);
-	} else if (format) {
-		if (!entry->format)
-			ret = marker_set_format(entry, format);
-		else if (strcmp(entry->format, format))
-			ret = -EPERM;
-	}
-	if (ret)
-		goto end;
-
-	/*
-	 * If we detect that a call_rcu is pending for this marker,
-	 * make sure it's executed now.
-	 */
-	if (entry->rcu_pending)
-		rcu_barrier_sched();
-	old = marker_entry_add_probe(entry, probe, probe_private);
-	if (IS_ERR(old)) {
-		ret = PTR_ERR(old);
-		goto end;
-	}
-	mutex_unlock(&markers_mutex);
-	marker_update_probes();
-	mutex_lock(&markers_mutex);
-	entry = get_marker(name);
-	if (!entry)
-		goto end;
-	if (entry->rcu_pending)
-		rcu_barrier_sched();
-	entry->oldptr = old;
-	entry->rcu_pending = 1;
-	/* write rcu_pending before calling the RCU callback */
-	smp_wmb();
-	call_rcu_sched(&entry->rcu, free_old_closure);
-end:
-	mutex_unlock(&markers_mutex);
-	return ret;
-}
-EXPORT_SYMBOL_GPL(marker_probe_register);
-
-/**
- * marker_probe_unregister -  Disconnect a probe from a marker
- * @name: marker name
- * @probe: probe function pointer
- * @probe_private: probe private data
- *
- * Returns the private data given to marker_probe_register, or an ERR_PTR().
- * We do not need to call a synchronize_sched to make sure the probes have
- * finished running before doing a module unload, because the module unload
- * itself uses stop_machine(), which insures that every preempt disabled section
- * have finished.
- */
-int marker_probe_unregister(const char *name,
-	marker_probe_func *probe, void *probe_private)
-{
-	struct marker_entry *entry;
-	struct marker_probe_closure *old;
-	int ret = -ENOENT;
-
-	mutex_lock(&markers_mutex);
-	entry = get_marker(name);
-	if (!entry)
-		goto end;
-	if (entry->rcu_pending)
-		rcu_barrier_sched();
-	old = marker_entry_remove_probe(entry, probe, probe_private);
-	mutex_unlock(&markers_mutex);
-	marker_update_probes();
-	mutex_lock(&markers_mutex);
-	entry = get_marker(name);
-	if (!entry)
-		goto end;
-	if (entry->rcu_pending)
-		rcu_barrier_sched();
-	entry->oldptr = old;
-	entry->rcu_pending = 1;
-	/* write rcu_pending before calling the RCU callback */
-	smp_wmb();
-	call_rcu_sched(&entry->rcu, free_old_closure);
-	remove_marker(name);	/* Ignore busy error message */
-	ret = 0;
-end:
-	mutex_unlock(&markers_mutex);
-	return ret;
-}
-EXPORT_SYMBOL_GPL(marker_probe_unregister);
-
-static struct marker_entry *
-get_marker_from_private_data(marker_probe_func *probe, void *probe_private)
-{
-	struct marker_entry *entry;
-	unsigned int i;
-	struct hlist_head *head;
-	struct hlist_node *node;
-
-	for (i = 0; i < MARKER_TABLE_SIZE; i++) {
-		head = &marker_table[i];
-		hlist_for_each_entry(entry, node, head, hlist) {
-			if (!entry->ptype) {
-				if (entry->single.func == probe
-						&& entry->single.probe_private
-						== probe_private)
-					return entry;
-			} else {
-				struct marker_probe_closure *closure;
-				closure = entry->multi;
-				for (i = 0; closure[i].func; i++) {
-					if (closure[i].func == probe &&
-							closure[i].probe_private
-							== probe_private)
-						return entry;
-				}
-			}
-		}
-	}
-	return NULL;
-}
-
-/**
- * marker_probe_unregister_private_data -  Disconnect a probe from a marker
- * @probe: probe function
- * @probe_private: probe private data
- *
- * Unregister a probe by providing the registered private data.
- * Only removes the first marker found in hash table.
- * Return 0 on success or error value.
- * We do not need to call a synchronize_sched to make sure the probes have
- * finished running before doing a module unload, because the module unload
- * itself uses stop_machine(), which insures that every preempt disabled section
- * have finished.
- */
-int marker_probe_unregister_private_data(marker_probe_func *probe,
-		void *probe_private)
-{
-	struct marker_entry *entry;
-	int ret = 0;
-	struct marker_probe_closure *old;
-
-	mutex_lock(&markers_mutex);
-	entry = get_marker_from_private_data(probe, probe_private);
-	if (!entry) {
-		ret = -ENOENT;
-		goto end;
-	}
-	if (entry->rcu_pending)
-		rcu_barrier_sched();
-	old = marker_entry_remove_probe(entry, NULL, probe_private);
-	mutex_unlock(&markers_mutex);
-	marker_update_probes();
-	mutex_lock(&markers_mutex);
-	entry = get_marker_from_private_data(probe, probe_private);
-	if (!entry)
-		goto end;
-	if (entry->rcu_pending)
-		rcu_barrier_sched();
-	entry->oldptr = old;
-	entry->rcu_pending = 1;
-	/* write rcu_pending before calling the RCU callback */
-	smp_wmb();
-	call_rcu_sched(&entry->rcu, free_old_closure);
-	remove_marker(entry->name);	/* Ignore busy error message */
-end:
-	mutex_unlock(&markers_mutex);
-	return ret;
-}
-EXPORT_SYMBOL_GPL(marker_probe_unregister_private_data);
-
-/**
- * marker_get_private_data - Get a marker's probe private data
- * @name: marker name
- * @probe: probe to match
- * @num: get the nth matching probe's private data
- *
- * Returns the nth private data pointer (starting from 0) matching, or an
- * ERR_PTR.
- * Returns the private data pointer, or an ERR_PTR.
- * The private data pointer should _only_ be dereferenced if the caller is the
- * owner of the data, or its content could vanish. This is mostly used to
- * confirm that a caller is the owner of a registered probe.
- */
-void *marker_get_private_data(const char *name, marker_probe_func *probe,
-		int num)
-{
-	struct hlist_head *head;
-	struct hlist_node *node;
-	struct marker_entry *e;
-	size_t name_len = strlen(name) + 1;
-	u32 hash = jhash(name, name_len-1, 0);
-	int i;
-
-	head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
-	hlist_for_each_entry(e, node, head, hlist) {
-		if (!strcmp(name, e->name)) {
-			if (!e->ptype) {
-				if (num == 0 && e->single.func == probe)
-					return e->single.probe_private;
-			} else {
-				struct marker_probe_closure *closure;
-				int match = 0;
-				closure = e->multi;
-				for (i = 0; closure[i].func; i++) {
-					if (closure[i].func != probe)
-						continue;
-					if (match++ == num)
-						return closure[i].probe_private;
-				}
-			}
-			break;
-		}
-	}
-	return ERR_PTR(-ENOENT);
-}
-EXPORT_SYMBOL_GPL(marker_get_private_data);
-
-#ifdef CONFIG_MODULES
-
-int marker_module_notify(struct notifier_block *self,
-			 unsigned long val, void *data)
-{
-	struct module *mod = data;
-
-	switch (val) {
-	case MODULE_STATE_COMING:
-		marker_update_probe_range(mod->markers,
-			mod->markers + mod->num_markers);
-		break;
-	case MODULE_STATE_GOING:
-		marker_update_probe_range(mod->markers,
-			mod->markers + mod->num_markers);
-		break;
-	}
-	return 0;
-}
-
-struct notifier_block marker_module_nb = {
-	.notifier_call = marker_module_notify,
-	.priority = 0,
-};
-
-static int init_markers(void)
-{
-	return register_module_notifier(&marker_module_nb);
-}
-__initcall(init_markers);
-
-#endif /* CONFIG_MODULES */
diff --git a/kernel/module.c b/kernel/module.c
index 46580ed..e6bc4b2 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -47,6 +47,7 @@
 #include <linux/rculist.h>
 #include <asm/uaccess.h>
 #include <asm/cacheflush.h>
+#include <asm/mmu_context.h>
 #include <linux/license.h>
 #include <asm/sections.h>
 #include <linux/tracepoint.h>
@@ -369,7 +370,7 @@ EXPORT_SYMBOL_GPL(find_module);
 
 #ifdef CONFIG_SMP
 
-#ifdef CONFIG_HAVE_DYNAMIC_PER_CPU_AREA
+#ifndef CONFIG_HAVE_LEGACY_PER_CPU_AREA
 
 static void *percpu_modalloc(unsigned long size, unsigned long align,
 			     const char *name)
@@ -394,7 +395,7 @@ static void percpu_modfree(void *freeme)
 	free_percpu(freeme);
 }
 
-#else /* ... !CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */
+#else /* ... CONFIG_HAVE_LEGACY_PER_CPU_AREA */
 
 /* Number of blocks used and allocated. */
 static unsigned int pcpu_num_used, pcpu_num_allocated;
@@ -540,7 +541,7 @@ static int percpu_modinit(void)
 }
 __initcall(percpu_modinit);
 
-#endif /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */
+#endif /* CONFIG_HAVE_LEGACY_PER_CPU_AREA */
 
 static unsigned int find_pcpusec(Elf_Ehdr *hdr,
 				 Elf_Shdr *sechdrs,
@@ -1535,6 +1536,10 @@ static void free_module(struct module *mod)
 
 	/* Finally, free the core (containing the module structure) */
 	module_free(mod, mod->module_core);
+
+#ifdef CONFIG_MPU
+	update_protections(current->mm);
+#endif
 }
 
 void *__symbol_get(const char *symbol)
@@ -2237,10 +2242,6 @@ static noinline struct module *load_module(void __user *umod,
 				  sizeof(*mod->ctors), &mod->num_ctors);
 #endif
 
-#ifdef CONFIG_MARKERS
-	mod->markers = section_objs(hdr, sechdrs, secstrings, "__markers",
-				    sizeof(*mod->markers), &mod->num_markers);
-#endif
 #ifdef CONFIG_TRACEPOINTS
 	mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
 					"__tracepoints",
@@ -2958,20 +2959,6 @@ void module_layout(struct module *mod,
 EXPORT_SYMBOL(module_layout);
 #endif
 
-#ifdef CONFIG_MARKERS
-void module_update_markers(void)
-{
-	struct module *mod;
-
-	mutex_lock(&module_mutex);
-	list_for_each_entry(mod, &modules, list)
-		if (!mod->taints)
-			marker_update_probe_range(mod->markers,
-				mod->markers + mod->num_markers);
-	mutex_unlock(&module_mutex);
-}
-#endif
-
 #ifdef CONFIG_TRACEPOINTS
 void module_update_tracepoints(void)
 {
diff --git a/kernel/panic.c b/kernel/panic.c
index 512ab73..bcdef26 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -177,7 +177,7 @@ static const struct tnt tnts[] = {
  *  'W' - Taint on warning.
  *  'C' - modules from drivers/staging are loaded.
  *
- *	The string is overwritten by the next call to print_taint().
+ *	The string is overwritten by the next call to print_tainted().
  */
 const char *print_tainted(void)
 {
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
deleted file mode 100644
index d7cbc57..0000000
--- a/kernel/perf_counter.c
+++ /dev/null
@@ -1,4861 +0,0 @@
-/*
- * Performance counter core code
- *
- *  Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
- *  Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar
- *  Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
- *  Copyright  ©  2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
- *
- *  For licensing details see kernel-base/COPYING
- */
-
-#include <linux/fs.h>
-#include <linux/mm.h>
-#include <linux/cpu.h>
-#include <linux/smp.h>
-#include <linux/file.h>
-#include <linux/poll.h>
-#include <linux/sysfs.h>
-#include <linux/dcache.h>
-#include <linux/percpu.h>
-#include <linux/ptrace.h>
-#include <linux/vmstat.h>
-#include <linux/hardirq.h>
-#include <linux/rculist.h>
-#include <linux/uaccess.h>
-#include <linux/syscalls.h>
-#include <linux/anon_inodes.h>
-#include <linux/kernel_stat.h>
-#include <linux/perf_counter.h>
-
-#include <asm/irq_regs.h>
-
-/*
- * Each CPU has a list of per CPU counters:
- */
-DEFINE_PER_CPU(struct perf_cpu_context, perf_cpu_context);
-
-int perf_max_counters __read_mostly = 1;
-static int perf_reserved_percpu __read_mostly;
-static int perf_overcommit __read_mostly = 1;
-
-static atomic_t nr_counters __read_mostly;
-static atomic_t nr_mmap_counters __read_mostly;
-static atomic_t nr_comm_counters __read_mostly;
-static atomic_t nr_task_counters __read_mostly;
-
-/*
- * perf counter paranoia level:
- *  0 - not paranoid
- *  1 - disallow cpu counters to unpriv
- *  2 - disallow kernel profiling to unpriv
- */
-int sysctl_perf_counter_paranoid __read_mostly = 1;
-
-static inline bool perf_paranoid_cpu(void)
-{
-	return sysctl_perf_counter_paranoid > 0;
-}
-
-static inline bool perf_paranoid_kernel(void)
-{
-	return sysctl_perf_counter_paranoid > 1;
-}
-
-int sysctl_perf_counter_mlock __read_mostly = 512; /* 'free' kb per user */
-
-/*
- * max perf counter sample rate
- */
-int sysctl_perf_counter_sample_rate __read_mostly = 100000;
-
-static atomic64_t perf_counter_id;
-
-/*
- * Lock for (sysadmin-configurable) counter reservations:
- */
-static DEFINE_SPINLOCK(perf_resource_lock);
-
-/*
- * Architecture provided APIs - weak aliases:
- */
-extern __weak const struct pmu *hw_perf_counter_init(struct perf_counter *counter)
-{
-	return NULL;
-}
-
-void __weak hw_perf_disable(void)		{ barrier(); }
-void __weak hw_perf_enable(void)		{ barrier(); }
-
-void __weak hw_perf_counter_setup(int cpu)	{ barrier(); }
-void __weak hw_perf_counter_setup_online(int cpu)	{ barrier(); }
-
-int __weak
-hw_perf_group_sched_in(struct perf_counter *group_leader,
-	       struct perf_cpu_context *cpuctx,
-	       struct perf_counter_context *ctx, int cpu)
-{
-	return 0;
-}
-
-void __weak perf_counter_print_debug(void)	{ }
-
-static DEFINE_PER_CPU(int, disable_count);
-
-void __perf_disable(void)
-{
-	__get_cpu_var(disable_count)++;
-}
-
-bool __perf_enable(void)
-{
-	return !--__get_cpu_var(disable_count);
-}
-
-void perf_disable(void)
-{
-	__perf_disable();
-	hw_perf_disable();
-}
-
-void perf_enable(void)
-{
-	if (__perf_enable())
-		hw_perf_enable();
-}
-
-static void get_ctx(struct perf_counter_context *ctx)
-{
-	WARN_ON(!atomic_inc_not_zero(&ctx->refcount));
-}
-
-static void free_ctx(struct rcu_head *head)
-{
-	struct perf_counter_context *ctx;
-
-	ctx = container_of(head, struct perf_counter_context, rcu_head);
-	kfree(ctx);
-}
-
-static void put_ctx(struct perf_counter_context *ctx)
-{
-	if (atomic_dec_and_test(&ctx->refcount)) {
-		if (ctx->parent_ctx)
-			put_ctx(ctx->parent_ctx);
-		if (ctx->task)
-			put_task_struct(ctx->task);
-		call_rcu(&ctx->rcu_head, free_ctx);
-	}
-}
-
-static void unclone_ctx(struct perf_counter_context *ctx)
-{
-	if (ctx->parent_ctx) {
-		put_ctx(ctx->parent_ctx);
-		ctx->parent_ctx = NULL;
-	}
-}
-
-/*
- * If we inherit counters we want to return the parent counter id
- * to userspace.
- */
-static u64 primary_counter_id(struct perf_counter *counter)
-{
-	u64 id = counter->id;
-
-	if (counter->parent)
-		id = counter->parent->id;
-
-	return id;
-}
-
-/*
- * Get the perf_counter_context for a task and lock it.
- * This has to cope with with the fact that until it is locked,
- * the context could get moved to another task.
- */
-static struct perf_counter_context *
-perf_lock_task_context(struct task_struct *task, unsigned long *flags)
-{
-	struct perf_counter_context *ctx;
-
-	rcu_read_lock();
- retry:
-	ctx = rcu_dereference(task->perf_counter_ctxp);
-	if (ctx) {
-		/*
-		 * If this context is a clone of another, it might
-		 * get swapped for another underneath us by
-		 * perf_counter_task_sched_out, though the
-		 * rcu_read_lock() protects us from any context
-		 * getting freed.  Lock the context and check if it
-		 * got swapped before we could get the lock, and retry
-		 * if so.  If we locked the right context, then it
-		 * can't get swapped on us any more.
-		 */
-		spin_lock_irqsave(&ctx->lock, *flags);
-		if (ctx != rcu_dereference(task->perf_counter_ctxp)) {
-			spin_unlock_irqrestore(&ctx->lock, *flags);
-			goto retry;
-		}
-
-		if (!atomic_inc_not_zero(&ctx->refcount)) {
-			spin_unlock_irqrestore(&ctx->lock, *flags);
-			ctx = NULL;
-		}
-	}
-	rcu_read_unlock();
-	return ctx;
-}
-
-/*
- * Get the context for a task and increment its pin_count so it
- * can't get swapped to another task.  This also increments its
- * reference count so that the context can't get freed.
- */
-static struct perf_counter_context *perf_pin_task_context(struct task_struct *task)
-{
-	struct perf_counter_context *ctx;
-	unsigned long flags;
-
-	ctx = perf_lock_task_context(task, &flags);
-	if (ctx) {
-		++ctx->pin_count;
-		spin_unlock_irqrestore(&ctx->lock, flags);
-	}
-	return ctx;
-}
-
-static void perf_unpin_context(struct perf_counter_context *ctx)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&ctx->lock, flags);
-	--ctx->pin_count;
-	spin_unlock_irqrestore(&ctx->lock, flags);
-	put_ctx(ctx);
-}
-
-/*
- * Add a counter from the lists for its context.
- * Must be called with ctx->mutex and ctx->lock held.
- */
-static void
-list_add_counter(struct perf_counter *counter, struct perf_counter_context *ctx)
-{
-	struct perf_counter *group_leader = counter->group_leader;
-
-	/*
-	 * Depending on whether it is a standalone or sibling counter,
-	 * add it straight to the context's counter list, or to the group
-	 * leader's sibling list:
-	 */
-	if (group_leader == counter)
-		list_add_tail(&counter->list_entry, &ctx->counter_list);
-	else {
-		list_add_tail(&counter->list_entry, &group_leader->sibling_list);
-		group_leader->nr_siblings++;
-	}
-
-	list_add_rcu(&counter->event_entry, &ctx->event_list);
-	ctx->nr_counters++;
-	if (counter->attr.inherit_stat)
-		ctx->nr_stat++;
-}
-
-/*
- * Remove a counter from the lists for its context.
- * Must be called with ctx->mutex and ctx->lock held.
- */
-static void
-list_del_counter(struct perf_counter *counter, struct perf_counter_context *ctx)
-{
-	struct perf_counter *sibling, *tmp;
-
-	if (list_empty(&counter->list_entry))
-		return;
-	ctx->nr_counters--;
-	if (counter->attr.inherit_stat)
-		ctx->nr_stat--;
-
-	list_del_init(&counter->list_entry);
-	list_del_rcu(&counter->event_entry);
-
-	if (counter->group_leader != counter)
-		counter->group_leader->nr_siblings--;
-
-	/*
-	 * If this was a group counter with sibling counters then
-	 * upgrade the siblings to singleton counters by adding them
-	 * to the context list directly:
-	 */
-	list_for_each_entry_safe(sibling, tmp,
-				 &counter->sibling_list, list_entry) {
-
-		list_move_tail(&sibling->list_entry, &ctx->counter_list);
-		sibling->group_leader = sibling;
-	}
-}
-
-static void
-counter_sched_out(struct perf_counter *counter,
-		  struct perf_cpu_context *cpuctx,
-		  struct perf_counter_context *ctx)
-{
-	if (counter->state != PERF_COUNTER_STATE_ACTIVE)
-		return;
-
-	counter->state = PERF_COUNTER_STATE_INACTIVE;
-	if (counter->pending_disable) {
-		counter->pending_disable = 0;
-		counter->state = PERF_COUNTER_STATE_OFF;
-	}
-	counter->tstamp_stopped = ctx->time;
-	counter->pmu->disable(counter);
-	counter->oncpu = -1;
-
-	if (!is_software_counter(counter))
-		cpuctx->active_oncpu--;
-	ctx->nr_active--;
-	if (counter->attr.exclusive || !cpuctx->active_oncpu)
-		cpuctx->exclusive = 0;
-}
-
-static void
-group_sched_out(struct perf_counter *group_counter,
-		struct perf_cpu_context *cpuctx,
-		struct perf_counter_context *ctx)
-{
-	struct perf_counter *counter;
-
-	if (group_counter->state != PERF_COUNTER_STATE_ACTIVE)
-		return;
-
-	counter_sched_out(group_counter, cpuctx, ctx);
-
-	/*
-	 * Schedule out siblings (if any):
-	 */
-	list_for_each_entry(counter, &group_counter->sibling_list, list_entry)
-		counter_sched_out(counter, cpuctx, ctx);
-
-	if (group_counter->attr.exclusive)
-		cpuctx->exclusive = 0;
-}
-
-/*
- * Cross CPU call to remove a performance counter
- *
- * We disable the counter on the hardware level first. After that we
- * remove it from the context list.
- */
-static void __perf_counter_remove_from_context(void *info)
-{
-	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
-	struct perf_counter *counter = info;
-	struct perf_counter_context *ctx = counter->ctx;
-
-	/*
-	 * If this is a task context, we need to check whether it is
-	 * the current task context of this cpu. If not it has been
-	 * scheduled out before the smp call arrived.
-	 */
-	if (ctx->task && cpuctx->task_ctx != ctx)
-		return;
-
-	spin_lock(&ctx->lock);
-	/*
-	 * Protect the list operation against NMI by disabling the
-	 * counters on a global level.
-	 */
-	perf_disable();
-
-	counter_sched_out(counter, cpuctx, ctx);
-
-	list_del_counter(counter, ctx);
-
-	if (!ctx->task) {
-		/*
-		 * Allow more per task counters with respect to the
-		 * reservation:
-		 */
-		cpuctx->max_pertask =
-			min(perf_max_counters - ctx->nr_counters,
-			    perf_max_counters - perf_reserved_percpu);
-	}
-
-	perf_enable();
-	spin_unlock(&ctx->lock);
-}
-
-
-/*
- * Remove the counter from a task's (or a CPU's) list of counters.
- *
- * Must be called with ctx->mutex held.
- *
- * CPU counters are removed with a smp call. For task counters we only
- * call when the task is on a CPU.
- *
- * If counter->ctx is a cloned context, callers must make sure that
- * every task struct that counter->ctx->task could possibly point to
- * remains valid.  This is OK when called from perf_release since
- * that only calls us on the top-level context, which can't be a clone.
- * When called from perf_counter_exit_task, it's OK because the
- * context has been detached from its task.
- */
-static void perf_counter_remove_from_context(struct perf_counter *counter)
-{
-	struct perf_counter_context *ctx = counter->ctx;
-	struct task_struct *task = ctx->task;
-
-	if (!task) {
-		/*
-		 * Per cpu counters are removed via an smp call and
-		 * the removal is always sucessful.
-		 */
-		smp_call_function_single(counter->cpu,
-					 __perf_counter_remove_from_context,
-					 counter, 1);
-		return;
-	}
-
-retry:
-	task_oncpu_function_call(task, __perf_counter_remove_from_context,
-				 counter);
-
-	spin_lock_irq(&ctx->lock);
-	/*
-	 * If the context is active we need to retry the smp call.
-	 */
-	if (ctx->nr_active && !list_empty(&counter->list_entry)) {
-		spin_unlock_irq(&ctx->lock);
-		goto retry;
-	}
-
-	/*
-	 * The lock prevents that this context is scheduled in so we
-	 * can remove the counter safely, if the call above did not
-	 * succeed.
-	 */
-	if (!list_empty(&counter->list_entry)) {
-		list_del_counter(counter, ctx);
-	}
-	spin_unlock_irq(&ctx->lock);
-}
-
-static inline u64 perf_clock(void)
-{
-	return cpu_clock(smp_processor_id());
-}
-
-/*
- * Update the record of the current time in a context.
- */
-static void update_context_time(struct perf_counter_context *ctx)
-{
-	u64 now = perf_clock();
-
-	ctx->time += now - ctx->timestamp;
-	ctx->timestamp = now;
-}
-
-/*
- * Update the total_time_enabled and total_time_running fields for a counter.
- */
-static void update_counter_times(struct perf_counter *counter)
-{
-	struct perf_counter_context *ctx = counter->ctx;
-	u64 run_end;
-
-	if (counter->state < PERF_COUNTER_STATE_INACTIVE)
-		return;
-
-	counter->total_time_enabled = ctx->time - counter->tstamp_enabled;
-
-	if (counter->state == PERF_COUNTER_STATE_INACTIVE)
-		run_end = counter->tstamp_stopped;
-	else
-		run_end = ctx->time;
-
-	counter->total_time_running = run_end - counter->tstamp_running;
-}
-
-/*
- * Update total_time_enabled and total_time_running for all counters in a group.
- */
-static void update_group_times(struct perf_counter *leader)
-{
-	struct perf_counter *counter;
-
-	update_counter_times(leader);
-	list_for_each_entry(counter, &leader->sibling_list, list_entry)
-		update_counter_times(counter);
-}
-
-/*
- * Cross CPU call to disable a performance counter
- */
-static void __perf_counter_disable(void *info)
-{
-	struct perf_counter *counter = info;
-	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
-	struct perf_counter_context *ctx = counter->ctx;
-
-	/*
-	 * If this is a per-task counter, need to check whether this
-	 * counter's task is the current task on this cpu.
-	 */
-	if (ctx->task && cpuctx->task_ctx != ctx)
-		return;
-
-	spin_lock(&ctx->lock);
-
-	/*
-	 * If the counter is on, turn it off.
-	 * If it is in error state, leave it in error state.
-	 */
-	if (counter->state >= PERF_COUNTER_STATE_INACTIVE) {
-		update_context_time(ctx);
-		update_counter_times(counter);
-		if (counter == counter->group_leader)
-			group_sched_out(counter, cpuctx, ctx);
-		else
-			counter_sched_out(counter, cpuctx, ctx);
-		counter->state = PERF_COUNTER_STATE_OFF;
-	}
-
-	spin_unlock(&ctx->lock);
-}
-
-/*
- * Disable a counter.
- *
- * If counter->ctx is a cloned context, callers must make sure that
- * every task struct that counter->ctx->task could possibly point to
- * remains valid.  This condition is satisifed when called through
- * perf_counter_for_each_child or perf_counter_for_each because they
- * hold the top-level counter's child_mutex, so any descendant that
- * goes to exit will block in sync_child_counter.
- * When called from perf_pending_counter it's OK because counter->ctx
- * is the current context on this CPU and preemption is disabled,
- * hence we can't get into perf_counter_task_sched_out for this context.
- */
-static void perf_counter_disable(struct perf_counter *counter)
-{
-	struct perf_counter_context *ctx = counter->ctx;
-	struct task_struct *task = ctx->task;
-
-	if (!task) {
-		/*
-		 * Disable the counter on the cpu that it's on
-		 */
-		smp_call_function_single(counter->cpu, __perf_counter_disable,
-					 counter, 1);
-		return;
-	}
-
- retry:
-	task_oncpu_function_call(task, __perf_counter_disable, counter);
-
-	spin_lock_irq(&ctx->lock);
-	/*
-	 * If the counter is still active, we need to retry the cross-call.
-	 */
-	if (counter->state == PERF_COUNTER_STATE_ACTIVE) {
-		spin_unlock_irq(&ctx->lock);
-		goto retry;
-	}
-
-	/*
-	 * Since we have the lock this context can't be scheduled
-	 * in, so we can change the state safely.
-	 */
-	if (counter->state == PERF_COUNTER_STATE_INACTIVE) {
-		update_counter_times(counter);
-		counter->state = PERF_COUNTER_STATE_OFF;
-	}
-
-	spin_unlock_irq(&ctx->lock);
-}
-
-static int
-counter_sched_in(struct perf_counter *counter,
-		 struct perf_cpu_context *cpuctx,
-		 struct perf_counter_context *ctx,
-		 int cpu)
-{
-	if (counter->state <= PERF_COUNTER_STATE_OFF)
-		return 0;
-
-	counter->state = PERF_COUNTER_STATE_ACTIVE;
-	counter->oncpu = cpu;	/* TODO: put 'cpu' into cpuctx->cpu */
-	/*
-	 * The new state must be visible before we turn it on in the hardware:
-	 */
-	smp_wmb();
-
-	if (counter->pmu->enable(counter)) {
-		counter->state = PERF_COUNTER_STATE_INACTIVE;
-		counter->oncpu = -1;
-		return -EAGAIN;
-	}
-
-	counter->tstamp_running += ctx->time - counter->tstamp_stopped;
-
-	if (!is_software_counter(counter))
-		cpuctx->active_oncpu++;
-	ctx->nr_active++;
-
-	if (counter->attr.exclusive)
-		cpuctx->exclusive = 1;
-
-	return 0;
-}
-
-static int
-group_sched_in(struct perf_counter *group_counter,
-	       struct perf_cpu_context *cpuctx,
-	       struct perf_counter_context *ctx,
-	       int cpu)
-{
-	struct perf_counter *counter, *partial_group;
-	int ret;
-
-	if (group_counter->state == PERF_COUNTER_STATE_OFF)
-		return 0;
-
-	ret = hw_perf_group_sched_in(group_counter, cpuctx, ctx, cpu);
-	if (ret)
-		return ret < 0 ? ret : 0;
-
-	if (counter_sched_in(group_counter, cpuctx, ctx, cpu))
-		return -EAGAIN;
-
-	/*
-	 * Schedule in siblings as one group (if any):
-	 */
-	list_for_each_entry(counter, &group_counter->sibling_list, list_entry) {
-		if (counter_sched_in(counter, cpuctx, ctx, cpu)) {
-			partial_group = counter;
-			goto group_error;
-		}
-	}
-
-	return 0;
-
-group_error:
-	/*
-	 * Groups can be scheduled in as one unit only, so undo any
-	 * partial group before returning:
-	 */
-	list_for_each_entry(counter, &group_counter->sibling_list, list_entry) {
-		if (counter == partial_group)
-			break;
-		counter_sched_out(counter, cpuctx, ctx);
-	}
-	counter_sched_out(group_counter, cpuctx, ctx);
-
-	return -EAGAIN;
-}
-
-/*
- * Return 1 for a group consisting entirely of software counters,
- * 0 if the group contains any hardware counters.
- */
-static int is_software_only_group(struct perf_counter *leader)
-{
-	struct perf_counter *counter;
-
-	if (!is_software_counter(leader))
-		return 0;
-
-	list_for_each_entry(counter, &leader->sibling_list, list_entry)
-		if (!is_software_counter(counter))
-			return 0;
-
-	return 1;
-}
-
-/*
- * Work out whether we can put this counter group on the CPU now.
- */
-static int group_can_go_on(struct perf_counter *counter,
-			   struct perf_cpu_context *cpuctx,
-			   int can_add_hw)
-{
-	/*
-	 * Groups consisting entirely of software counters can always go on.
-	 */
-	if (is_software_only_group(counter))
-		return 1;
-	/*
-	 * If an exclusive group is already on, no other hardware
-	 * counters can go on.
-	 */
-	if (cpuctx->exclusive)
-		return 0;
-	/*
-	 * If this group is exclusive and there are already
-	 * counters on the CPU, it can't go on.
-	 */
-	if (counter->attr.exclusive && cpuctx->active_oncpu)
-		return 0;
-	/*
-	 * Otherwise, try to add it if all previous groups were able
-	 * to go on.
-	 */
-	return can_add_hw;
-}
-
-static void add_counter_to_ctx(struct perf_counter *counter,
-			       struct perf_counter_context *ctx)
-{
-	list_add_counter(counter, ctx);
-	counter->tstamp_enabled = ctx->time;
-	counter->tstamp_running = ctx->time;
-	counter->tstamp_stopped = ctx->time;
-}
-
-/*
- * Cross CPU call to install and enable a performance counter
- *
- * Must be called with ctx->mutex held
- */
-static void __perf_install_in_context(void *info)
-{
-	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
-	struct perf_counter *counter = info;
-	struct perf_counter_context *ctx = counter->ctx;
-	struct perf_counter *leader = counter->group_leader;
-	int cpu = smp_processor_id();
-	int err;
-
-	/*
-	 * If this is a task context, we need to check whether it is
-	 * the current task context of this cpu. If not it has been
-	 * scheduled out before the smp call arrived.
-	 * Or possibly this is the right context but it isn't
-	 * on this cpu because it had no counters.
-	 */
-	if (ctx->task && cpuctx->task_ctx != ctx) {
-		if (cpuctx->task_ctx || ctx->task != current)
-			return;
-		cpuctx->task_ctx = ctx;
-	}
-
-	spin_lock(&ctx->lock);
-	ctx->is_active = 1;
-	update_context_time(ctx);
-
-	/*
-	 * Protect the list operation against NMI by disabling the
-	 * counters on a global level. NOP for non NMI based counters.
-	 */
-	perf_disable();
-
-	add_counter_to_ctx(counter, ctx);
-
-	/*
-	 * Don't put the counter on if it is disabled or if
-	 * it is in a group and the group isn't on.
-	 */
-	if (counter->state != PERF_COUNTER_STATE_INACTIVE ||
-	    (leader != counter && leader->state != PERF_COUNTER_STATE_ACTIVE))
-		goto unlock;
-
-	/*
-	 * An exclusive counter can't go on if there are already active
-	 * hardware counters, and no hardware counter can go on if there
-	 * is already an exclusive counter on.
-	 */
-	if (!group_can_go_on(counter, cpuctx, 1))
-		err = -EEXIST;
-	else
-		err = counter_sched_in(counter, cpuctx, ctx, cpu);
-
-	if (err) {
-		/*
-		 * This counter couldn't go on.  If it is in a group
-		 * then we have to pull the whole group off.
-		 * If the counter group is pinned then put it in error state.
-		 */
-		if (leader != counter)
-			group_sched_out(leader, cpuctx, ctx);
-		if (leader->attr.pinned) {
-			update_group_times(leader);
-			leader->state = PERF_COUNTER_STATE_ERROR;
-		}
-	}
-
-	if (!err && !ctx->task && cpuctx->max_pertask)
-		cpuctx->max_pertask--;
-
- unlock:
-	perf_enable();
-
-	spin_unlock(&ctx->lock);
-}
-
-/*
- * Attach a performance counter to a context
- *
- * First we add the counter to the list with the hardware enable bit
- * in counter->hw_config cleared.
- *
- * If the counter is attached to a task which is on a CPU we use a smp
- * call to enable it in the task context. The task might have been
- * scheduled away, but we check this in the smp call again.
- *
- * Must be called with ctx->mutex held.
- */
-static void
-perf_install_in_context(struct perf_counter_context *ctx,
-			struct perf_counter *counter,
-			int cpu)
-{
-	struct task_struct *task = ctx->task;
-
-	if (!task) {
-		/*
-		 * Per cpu counters are installed via an smp call and
-		 * the install is always sucessful.
-		 */
-		smp_call_function_single(cpu, __perf_install_in_context,
-					 counter, 1);
-		return;
-	}
-
-retry:
-	task_oncpu_function_call(task, __perf_install_in_context,
-				 counter);
-
-	spin_lock_irq(&ctx->lock);
-	/*
-	 * we need to retry the smp call.
-	 */
-	if (ctx->is_active && list_empty(&counter->list_entry)) {
-		spin_unlock_irq(&ctx->lock);
-		goto retry;
-	}
-
-	/*
-	 * The lock prevents that this context is scheduled in so we
-	 * can add the counter safely, if it the call above did not
-	 * succeed.
-	 */
-	if (list_empty(&counter->list_entry))
-		add_counter_to_ctx(counter, ctx);
-	spin_unlock_irq(&ctx->lock);
-}
-
-/*
- * Cross CPU call to enable a performance counter
- */
-static void __perf_counter_enable(void *info)
-{
-	struct perf_counter *counter = info;
-	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
-	struct perf_counter_context *ctx = counter->ctx;
-	struct perf_counter *leader = counter->group_leader;
-	int err;
-
-	/*
-	 * If this is a per-task counter, need to check whether this
-	 * counter's task is the current task on this cpu.
-	 */
-	if (ctx->task && cpuctx->task_ctx != ctx) {
-		if (cpuctx->task_ctx || ctx->task != current)
-			return;
-		cpuctx->task_ctx = ctx;
-	}
-
-	spin_lock(&ctx->lock);
-	ctx->is_active = 1;
-	update_context_time(ctx);
-
-	if (counter->state >= PERF_COUNTER_STATE_INACTIVE)
-		goto unlock;
-	counter->state = PERF_COUNTER_STATE_INACTIVE;
-	counter->tstamp_enabled = ctx->time - counter->total_time_enabled;
-
-	/*
-	 * If the counter is in a group and isn't the group leader,
-	 * then don't put it on unless the group is on.
-	 */
-	if (leader != counter && leader->state != PERF_COUNTER_STATE_ACTIVE)
-		goto unlock;
-
-	if (!group_can_go_on(counter, cpuctx, 1)) {
-		err = -EEXIST;
-	} else {
-		perf_disable();
-		if (counter == leader)
-			err = group_sched_in(counter, cpuctx, ctx,
-					     smp_processor_id());
-		else
-			err = counter_sched_in(counter, cpuctx, ctx,
-					       smp_processor_id());
-		perf_enable();
-	}
-
-	if (err) {
-		/*
-		 * If this counter can't go on and it's part of a
-		 * group, then the whole group has to come off.
-		 */
-		if (leader != counter)
-			group_sched_out(leader, cpuctx, ctx);
-		if (leader->attr.pinned) {
-			update_group_times(leader);
-			leader->state = PERF_COUNTER_STATE_ERROR;
-		}
-	}
-
- unlock:
-	spin_unlock(&ctx->lock);
-}
-
-/*
- * Enable a counter.
- *
- * If counter->ctx is a cloned context, callers must make sure that
- * every task struct that counter->ctx->task could possibly point to
- * remains valid.  This condition is satisfied when called through
- * perf_counter_for_each_child or perf_counter_for_each as described
- * for perf_counter_disable.
- */
-static void perf_counter_enable(struct perf_counter *counter)
-{
-	struct perf_counter_context *ctx = counter->ctx;
-	struct task_struct *task = ctx->task;
-
-	if (!task) {
-		/*
-		 * Enable the counter on the cpu that it's on
-		 */
-		smp_call_function_single(counter->cpu, __perf_counter_enable,
-					 counter, 1);
-		return;
-	}
-
-	spin_lock_irq(&ctx->lock);
-	if (counter->state >= PERF_COUNTER_STATE_INACTIVE)
-		goto out;
-
-	/*
-	 * If the counter is in error state, clear that first.
-	 * That way, if we see the counter in error state below, we
-	 * know that it has gone back into error state, as distinct
-	 * from the task having been scheduled away before the
-	 * cross-call arrived.
-	 */
-	if (counter->state == PERF_COUNTER_STATE_ERROR)
-		counter->state = PERF_COUNTER_STATE_OFF;
-
- retry:
-	spin_unlock_irq(&ctx->lock);
-	task_oncpu_function_call(task, __perf_counter_enable, counter);
-
-	spin_lock_irq(&ctx->lock);
-
-	/*
-	 * If the context is active and the counter is still off,
-	 * we need to retry the cross-call.
-	 */
-	if (ctx->is_active && counter->state == PERF_COUNTER_STATE_OFF)
-		goto retry;
-
-	/*
-	 * Since we have the lock this context can't be scheduled
-	 * in, so we can change the state safely.
-	 */
-	if (counter->state == PERF_COUNTER_STATE_OFF) {
-		counter->state = PERF_COUNTER_STATE_INACTIVE;
-		counter->tstamp_enabled =
-			ctx->time - counter->total_time_enabled;
-	}
- out:
-	spin_unlock_irq(&ctx->lock);
-}
-
-static int perf_counter_refresh(struct perf_counter *counter, int refresh)
-{
-	/*
-	 * not supported on inherited counters
-	 */
-	if (counter->attr.inherit)
-		return -EINVAL;
-
-	atomic_add(refresh, &counter->event_limit);
-	perf_counter_enable(counter);
-
-	return 0;
-}
-
-void __perf_counter_sched_out(struct perf_counter_context *ctx,
-			      struct perf_cpu_context *cpuctx)
-{
-	struct perf_counter *counter;
-
-	spin_lock(&ctx->lock);
-	ctx->is_active = 0;
-	if (likely(!ctx->nr_counters))
-		goto out;
-	update_context_time(ctx);
-
-	perf_disable();
-	if (ctx->nr_active) {
-		list_for_each_entry(counter, &ctx->counter_list, list_entry) {
-			if (counter != counter->group_leader)
-				counter_sched_out(counter, cpuctx, ctx);
-			else
-				group_sched_out(counter, cpuctx, ctx);
-		}
-	}
-	perf_enable();
- out:
-	spin_unlock(&ctx->lock);
-}
-
-/*
- * Test whether two contexts are equivalent, i.e. whether they
- * have both been cloned from the same version of the same context
- * and they both have the same number of enabled counters.
- * If the number of enabled counters is the same, then the set
- * of enabled counters should be the same, because these are both
- * inherited contexts, therefore we can't access individual counters
- * in them directly with an fd; we can only enable/disable all
- * counters via prctl, or enable/disable all counters in a family
- * via ioctl, which will have the same effect on both contexts.
- */
-static int context_equiv(struct perf_counter_context *ctx1,
-			 struct perf_counter_context *ctx2)
-{
-	return ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx
-		&& ctx1->parent_gen == ctx2->parent_gen
-		&& !ctx1->pin_count && !ctx2->pin_count;
-}
-
-static void __perf_counter_read(void *counter);
-
-static void __perf_counter_sync_stat(struct perf_counter *counter,
-				     struct perf_counter *next_counter)
-{
-	u64 value;
-
-	if (!counter->attr.inherit_stat)
-		return;
-
-	/*
-	 * Update the counter value, we cannot use perf_counter_read()
-	 * because we're in the middle of a context switch and have IRQs
-	 * disabled, which upsets smp_call_function_single(), however
-	 * we know the counter must be on the current CPU, therefore we
-	 * don't need to use it.
-	 */
-	switch (counter->state) {
-	case PERF_COUNTER_STATE_ACTIVE:
-		__perf_counter_read(counter);
-		break;
-
-	case PERF_COUNTER_STATE_INACTIVE:
-		update_counter_times(counter);
-		break;
-
-	default:
-		break;
-	}
-
-	/*
-	 * In order to keep per-task stats reliable we need to flip the counter
-	 * values when we flip the contexts.
-	 */
-	value = atomic64_read(&next_counter->count);
-	value = atomic64_xchg(&counter->count, value);
-	atomic64_set(&next_counter->count, value);
-
-	swap(counter->total_time_enabled, next_counter->total_time_enabled);
-	swap(counter->total_time_running, next_counter->total_time_running);
-
-	/*
-	 * Since we swizzled the values, update the user visible data too.
-	 */
-	perf_counter_update_userpage(counter);
-	perf_counter_update_userpage(next_counter);
-}
-
-#define list_next_entry(pos, member) \
-	list_entry(pos->member.next, typeof(*pos), member)
-
-static void perf_counter_sync_stat(struct perf_counter_context *ctx,
-				   struct perf_counter_context *next_ctx)
-{
-	struct perf_counter *counter, *next_counter;
-
-	if (!ctx->nr_stat)
-		return;
-
-	counter = list_first_entry(&ctx->event_list,
-				   struct perf_counter, event_entry);
-
-	next_counter = list_first_entry(&next_ctx->event_list,
-					struct perf_counter, event_entry);
-
-	while (&counter->event_entry != &ctx->event_list &&
-	       &next_counter->event_entry != &next_ctx->event_list) {
-
-		__perf_counter_sync_stat(counter, next_counter);
-
-		counter = list_next_entry(counter, event_entry);
-		next_counter = list_next_entry(next_counter, event_entry);
-	}
-}
-
-/*
- * Called from scheduler to remove the counters of the current task,
- * with interrupts disabled.
- *
- * We stop each counter and update the counter value in counter->count.
- *
- * This does not protect us against NMI, but disable()
- * sets the disabled bit in the control field of counter _before_
- * accessing the counter control register. If a NMI hits, then it will
- * not restart the counter.
- */
-void perf_counter_task_sched_out(struct task_struct *task,
-				 struct task_struct *next, int cpu)
-{
-	struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
-	struct perf_counter_context *ctx = task->perf_counter_ctxp;
-	struct perf_counter_context *next_ctx;
-	struct perf_counter_context *parent;
-	struct pt_regs *regs;
-	int do_switch = 1;
-
-	regs = task_pt_regs(task);
-	perf_swcounter_event(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 1, regs, 0);
-
-	if (likely(!ctx || !cpuctx->task_ctx))
-		return;
-
-	update_context_time(ctx);
-
-	rcu_read_lock();
-	parent = rcu_dereference(ctx->parent_ctx);
-	next_ctx = next->perf_counter_ctxp;
-	if (parent && next_ctx &&
-	    rcu_dereference(next_ctx->parent_ctx) == parent) {
-		/*
-		 * Looks like the two contexts are clones, so we might be
-		 * able to optimize the context switch.  We lock both
-		 * contexts and check that they are clones under the
-		 * lock (including re-checking that neither has been
-		 * uncloned in the meantime).  It doesn't matter which
-		 * order we take the locks because no other cpu could
-		 * be trying to lock both of these tasks.
-		 */
-		spin_lock(&ctx->lock);
-		spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING);
-		if (context_equiv(ctx, next_ctx)) {
-			/*
-			 * XXX do we need a memory barrier of sorts
-			 * wrt to rcu_dereference() of perf_counter_ctxp
-			 */
-			task->perf_counter_ctxp = next_ctx;
-			next->perf_counter_ctxp = ctx;
-			ctx->task = next;
-			next_ctx->task = task;
-			do_switch = 0;
-
-			perf_counter_sync_stat(ctx, next_ctx);
-		}
-		spin_unlock(&next_ctx->lock);
-		spin_unlock(&ctx->lock);
-	}
-	rcu_read_unlock();
-
-	if (do_switch) {
-		__perf_counter_sched_out(ctx, cpuctx);
-		cpuctx->task_ctx = NULL;
-	}
-}
-
-/*
- * Called with IRQs disabled
- */
-static void __perf_counter_task_sched_out(struct perf_counter_context *ctx)
-{
-	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
-
-	if (!cpuctx->task_ctx)
-		return;
-
-	if (WARN_ON_ONCE(ctx != cpuctx->task_ctx))
-		return;
-
-	__perf_counter_sched_out(ctx, cpuctx);
-	cpuctx->task_ctx = NULL;
-}
-
-/*
- * Called with IRQs disabled
- */
-static void perf_counter_cpu_sched_out(struct perf_cpu_context *cpuctx)
-{
-	__perf_counter_sched_out(&cpuctx->ctx, cpuctx);
-}
-
-static void
-__perf_counter_sched_in(struct perf_counter_context *ctx,
-			struct perf_cpu_context *cpuctx, int cpu)
-{
-	struct perf_counter *counter;
-	int can_add_hw = 1;
-
-	spin_lock(&ctx->lock);
-	ctx->is_active = 1;
-	if (likely(!ctx->nr_counters))
-		goto out;
-
-	ctx->timestamp = perf_clock();
-
-	perf_disable();
-
-	/*
-	 * First go through the list and put on any pinned groups
-	 * in order to give them the best chance of going on.
-	 */
-	list_for_each_entry(counter, &ctx->counter_list, list_entry) {
-		if (counter->state <= PERF_COUNTER_STATE_OFF ||
-		    !counter->attr.pinned)
-			continue;
-		if (counter->cpu != -1 && counter->cpu != cpu)
-			continue;
-
-		if (counter != counter->group_leader)
-			counter_sched_in(counter, cpuctx, ctx, cpu);
-		else {
-			if (group_can_go_on(counter, cpuctx, 1))
-				group_sched_in(counter, cpuctx, ctx, cpu);
-		}
-
-		/*
-		 * If this pinned group hasn't been scheduled,
-		 * put it in error state.
-		 */
-		if (counter->state == PERF_COUNTER_STATE_INACTIVE) {
-			update_group_times(counter);
-			counter->state = PERF_COUNTER_STATE_ERROR;
-		}
-	}
-
-	list_for_each_entry(counter, &ctx->counter_list, list_entry) {
-		/*
-		 * Ignore counters in OFF or ERROR state, and
-		 * ignore pinned counters since we did them already.
-		 */
-		if (counter->state <= PERF_COUNTER_STATE_OFF ||
-		    counter->attr.pinned)
-			continue;
-
-		/*
-		 * Listen to the 'cpu' scheduling filter constraint
-		 * of counters:
-		 */
-		if (counter->cpu != -1 && counter->cpu != cpu)
-			continue;
-
-		if (counter != counter->group_leader) {
-			if (counter_sched_in(counter, cpuctx, ctx, cpu))
-				can_add_hw = 0;
-		} else {
-			if (group_can_go_on(counter, cpuctx, can_add_hw)) {
-				if (group_sched_in(counter, cpuctx, ctx, cpu))
-					can_add_hw = 0;
-			}
-		}
-	}
-	perf_enable();
- out:
-	spin_unlock(&ctx->lock);
-}
-
-/*
- * Called from scheduler to add the counters of the current task
- * with interrupts disabled.
- *
- * We restore the counter value and then enable it.
- *
- * This does not protect us against NMI, but enable()
- * sets the enabled bit in the control field of counter _before_
- * accessing the counter control register. If a NMI hits, then it will
- * keep the counter running.
- */
-void perf_counter_task_sched_in(struct task_struct *task, int cpu)
-{
-	struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
-	struct perf_counter_context *ctx = task->perf_counter_ctxp;
-
-	if (likely(!ctx))
-		return;
-	if (cpuctx->task_ctx == ctx)
-		return;
-	__perf_counter_sched_in(ctx, cpuctx, cpu);
-	cpuctx->task_ctx = ctx;
-}
-
-static void perf_counter_cpu_sched_in(struct perf_cpu_context *cpuctx, int cpu)
-{
-	struct perf_counter_context *ctx = &cpuctx->ctx;
-
-	__perf_counter_sched_in(ctx, cpuctx, cpu);
-}
-
-#define MAX_INTERRUPTS (~0ULL)
-
-static void perf_log_throttle(struct perf_counter *counter, int enable);
-
-static void perf_adjust_period(struct perf_counter *counter, u64 events)
-{
-	struct hw_perf_counter *hwc = &counter->hw;
-	u64 period, sample_period;
-	s64 delta;
-
-	events *= hwc->sample_period;
-	period = div64_u64(events, counter->attr.sample_freq);
-
-	delta = (s64)(period - hwc->sample_period);
-	delta = (delta + 7) / 8; /* low pass filter */
-
-	sample_period = hwc->sample_period + delta;
-
-	if (!sample_period)
-		sample_period = 1;
-
-	hwc->sample_period = sample_period;
-}
-
-static void perf_ctx_adjust_freq(struct perf_counter_context *ctx)
-{
-	struct perf_counter *counter;
-	struct hw_perf_counter *hwc;
-	u64 interrupts, freq;
-
-	spin_lock(&ctx->lock);
-	list_for_each_entry(counter, &ctx->counter_list, list_entry) {
-		if (counter->state != PERF_COUNTER_STATE_ACTIVE)
-			continue;
-
-		hwc = &counter->hw;
-
-		interrupts = hwc->interrupts;
-		hwc->interrupts = 0;
-
-		/*
-		 * unthrottle counters on the tick
-		 */
-		if (interrupts == MAX_INTERRUPTS) {
-			perf_log_throttle(counter, 1);
-			counter->pmu->unthrottle(counter);
-			interrupts = 2*sysctl_perf_counter_sample_rate/HZ;
-		}
-
-		if (!counter->attr.freq || !counter->attr.sample_freq)
-			continue;
-
-		/*
-		 * if the specified freq < HZ then we need to skip ticks
-		 */
-		if (counter->attr.sample_freq < HZ) {
-			freq = counter->attr.sample_freq;
-
-			hwc->freq_count += freq;
-			hwc->freq_interrupts += interrupts;
-
-			if (hwc->freq_count < HZ)
-				continue;
-
-			interrupts = hwc->freq_interrupts;
-			hwc->freq_interrupts = 0;
-			hwc->freq_count -= HZ;
-		} else
-			freq = HZ;
-
-		perf_adjust_period(counter, freq * interrupts);
-
-		/*
-		 * In order to avoid being stalled by an (accidental) huge
-		 * sample period, force reset the sample period if we didn't
-		 * get any events in this freq period.
-		 */
-		if (!interrupts) {
-			perf_disable();
-			counter->pmu->disable(counter);
-			atomic64_set(&hwc->period_left, 0);
-			counter->pmu->enable(counter);
-			perf_enable();
-		}
-	}
-	spin_unlock(&ctx->lock);
-}
-
-/*
- * Round-robin a context's counters:
- */
-static void rotate_ctx(struct perf_counter_context *ctx)
-{
-	struct perf_counter *counter;
-
-	if (!ctx->nr_counters)
-		return;
-
-	spin_lock(&ctx->lock);
-	/*
-	 * Rotate the first entry last (works just fine for group counters too):
-	 */
-	perf_disable();
-	list_for_each_entry(counter, &ctx->counter_list, list_entry) {
-		list_move_tail(&counter->list_entry, &ctx->counter_list);
-		break;
-	}
-	perf_enable();
-
-	spin_unlock(&ctx->lock);
-}
-
-void perf_counter_task_tick(struct task_struct *curr, int cpu)
-{
-	struct perf_cpu_context *cpuctx;
-	struct perf_counter_context *ctx;
-
-	if (!atomic_read(&nr_counters))
-		return;
-
-	cpuctx = &per_cpu(perf_cpu_context, cpu);
-	ctx = curr->perf_counter_ctxp;
-
-	perf_ctx_adjust_freq(&cpuctx->ctx);
-	if (ctx)
-		perf_ctx_adjust_freq(ctx);
-
-	perf_counter_cpu_sched_out(cpuctx);
-	if (ctx)
-		__perf_counter_task_sched_out(ctx);
-
-	rotate_ctx(&cpuctx->ctx);
-	if (ctx)
-		rotate_ctx(ctx);
-
-	perf_counter_cpu_sched_in(cpuctx, cpu);
-	if (ctx)
-		perf_counter_task_sched_in(curr, cpu);
-}
-
-/*
- * Enable all of a task's counters that have been marked enable-on-exec.
- * This expects task == current.
- */
-static void perf_counter_enable_on_exec(struct task_struct *task)
-{
-	struct perf_counter_context *ctx;
-	struct perf_counter *counter;
-	unsigned long flags;
-	int enabled = 0;
-
-	local_irq_save(flags);
-	ctx = task->perf_counter_ctxp;
-	if (!ctx || !ctx->nr_counters)
-		goto out;
-
-	__perf_counter_task_sched_out(ctx);
-
-	spin_lock(&ctx->lock);
-
-	list_for_each_entry(counter, &ctx->counter_list, list_entry) {
-		if (!counter->attr.enable_on_exec)
-			continue;
-		counter->attr.enable_on_exec = 0;
-		if (counter->state >= PERF_COUNTER_STATE_INACTIVE)
-			continue;
-		counter->state = PERF_COUNTER_STATE_INACTIVE;
-		counter->tstamp_enabled =
-			ctx->time - counter->total_time_enabled;
-		enabled = 1;
-	}
-
-	/*
-	 * Unclone this context if we enabled any counter.
-	 */
-	if (enabled)
-		unclone_ctx(ctx);
-
-	spin_unlock(&ctx->lock);
-
-	perf_counter_task_sched_in(task, smp_processor_id());
- out:
-	local_irq_restore(flags);
-}
-
-/*
- * Cross CPU call to read the hardware counter
- */
-static void __perf_counter_read(void *info)
-{
-	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
-	struct perf_counter *counter = info;
-	struct perf_counter_context *ctx = counter->ctx;
-	unsigned long flags;
-
-	/*
-	 * If this is a task context, we need to check whether it is
-	 * the current task context of this cpu.  If not it has been
-	 * scheduled out before the smp call arrived.  In that case
-	 * counter->count would have been updated to a recent sample
-	 * when the counter was scheduled out.
-	 */
-	if (ctx->task && cpuctx->task_ctx != ctx)
-		return;
-
-	local_irq_save(flags);
-	if (ctx->is_active)
-		update_context_time(ctx);
-	counter->pmu->read(counter);
-	update_counter_times(counter);
-	local_irq_restore(flags);
-}
-
-static u64 perf_counter_read(struct perf_counter *counter)
-{
-	/*
-	 * If counter is enabled and currently active on a CPU, update the
-	 * value in the counter structure:
-	 */
-	if (counter->state == PERF_COUNTER_STATE_ACTIVE) {
-		smp_call_function_single(counter->oncpu,
-					 __perf_counter_read, counter, 1);
-	} else if (counter->state == PERF_COUNTER_STATE_INACTIVE) {
-		update_counter_times(counter);
-	}
-
-	return atomic64_read(&counter->count);
-}
-
-/*
- * Initialize the perf_counter context in a task_struct:
- */
-static void
-__perf_counter_init_context(struct perf_counter_context *ctx,
-			    struct task_struct *task)
-{
-	memset(ctx, 0, sizeof(*ctx));
-	spin_lock_init(&ctx->lock);
-	mutex_init(&ctx->mutex);
-	INIT_LIST_HEAD(&ctx->counter_list);
-	INIT_LIST_HEAD(&ctx->event_list);
-	atomic_set(&ctx->refcount, 1);
-	ctx->task = task;
-}
-
-static struct perf_counter_context *find_get_context(pid_t pid, int cpu)
-{
-	struct perf_counter_context *ctx;
-	struct perf_cpu_context *cpuctx;
-	struct task_struct *task;
-	unsigned long flags;
-	int err;
-
-	/*
-	 * If cpu is not a wildcard then this is a percpu counter:
-	 */
-	if (cpu != -1) {
-		/* Must be root to operate on a CPU counter: */
-		if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN))
-			return ERR_PTR(-EACCES);
-
-		if (cpu < 0 || cpu > num_possible_cpus())
-			return ERR_PTR(-EINVAL);
-
-		/*
-		 * We could be clever and allow to attach a counter to an
-		 * offline CPU and activate it when the CPU comes up, but
-		 * that's for later.
-		 */
-		if (!cpu_isset(cpu, cpu_online_map))
-			return ERR_PTR(-ENODEV);
-
-		cpuctx = &per_cpu(perf_cpu_context, cpu);
-		ctx = &cpuctx->ctx;
-		get_ctx(ctx);
-
-		return ctx;
-	}
-
-	rcu_read_lock();
-	if (!pid)
-		task = current;
-	else
-		task = find_task_by_vpid(pid);
-	if (task)
-		get_task_struct(task);
-	rcu_read_unlock();
-
-	if (!task)
-		return ERR_PTR(-ESRCH);
-
-	/*
-	 * Can't attach counters to a dying task.
-	 */
-	err = -ESRCH;
-	if (task->flags & PF_EXITING)
-		goto errout;
-
-	/* Reuse ptrace permission checks for now. */
-	err = -EACCES;
-	if (!ptrace_may_access(task, PTRACE_MODE_READ))
-		goto errout;
-
- retry:
-	ctx = perf_lock_task_context(task, &flags);
-	if (ctx) {
-		unclone_ctx(ctx);
-		spin_unlock_irqrestore(&ctx->lock, flags);
-	}
-
-	if (!ctx) {
-		ctx = kmalloc(sizeof(struct perf_counter_context), GFP_KERNEL);
-		err = -ENOMEM;
-		if (!ctx)
-			goto errout;
-		__perf_counter_init_context(ctx, task);
-		get_ctx(ctx);
-		if (cmpxchg(&task->perf_counter_ctxp, NULL, ctx)) {
-			/*
-			 * We raced with some other task; use
-			 * the context they set.
-			 */
-			kfree(ctx);
-			goto retry;
-		}
-		get_task_struct(task);
-	}
-
-	put_task_struct(task);
-	return ctx;
-
- errout:
-	put_task_struct(task);
-	return ERR_PTR(err);
-}
-
-static void free_counter_rcu(struct rcu_head *head)
-{
-	struct perf_counter *counter;
-
-	counter = container_of(head, struct perf_counter, rcu_head);
-	if (counter->ns)
-		put_pid_ns(counter->ns);
-	kfree(counter);
-}
-
-static void perf_pending_sync(struct perf_counter *counter);
-
-static void free_counter(struct perf_counter *counter)
-{
-	perf_pending_sync(counter);
-
-	if (!counter->parent) {
-		atomic_dec(&nr_counters);
-		if (counter->attr.mmap)
-			atomic_dec(&nr_mmap_counters);
-		if (counter->attr.comm)
-			atomic_dec(&nr_comm_counters);
-		if (counter->attr.task)
-			atomic_dec(&nr_task_counters);
-	}
-
-	if (counter->destroy)
-		counter->destroy(counter);
-
-	put_ctx(counter->ctx);
-	call_rcu(&counter->rcu_head, free_counter_rcu);
-}
-
-/*
- * Called when the last reference to the file is gone.
- */
-static int perf_release(struct inode *inode, struct file *file)
-{
-	struct perf_counter *counter = file->private_data;
-	struct perf_counter_context *ctx = counter->ctx;
-
-	file->private_data = NULL;
-
-	WARN_ON_ONCE(ctx->parent_ctx);
-	mutex_lock(&ctx->mutex);
-	perf_counter_remove_from_context(counter);
-	mutex_unlock(&ctx->mutex);
-
-	mutex_lock(&counter->owner->perf_counter_mutex);
-	list_del_init(&counter->owner_entry);
-	mutex_unlock(&counter->owner->perf_counter_mutex);
-	put_task_struct(counter->owner);
-
-	free_counter(counter);
-
-	return 0;
-}
-
-static int perf_counter_read_size(struct perf_counter *counter)
-{
-	int entry = sizeof(u64); /* value */
-	int size = 0;
-	int nr = 1;
-
-	if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
-		size += sizeof(u64);
-
-	if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
-		size += sizeof(u64);
-
-	if (counter->attr.read_format & PERF_FORMAT_ID)
-		entry += sizeof(u64);
-
-	if (counter->attr.read_format & PERF_FORMAT_GROUP) {
-		nr += counter->group_leader->nr_siblings;
-		size += sizeof(u64);
-	}
-
-	size += entry * nr;
-
-	return size;
-}
-
-static u64 perf_counter_read_value(struct perf_counter *counter)
-{
-	struct perf_counter *child;
-	u64 total = 0;
-
-	total += perf_counter_read(counter);
-	list_for_each_entry(child, &counter->child_list, child_list)
-		total += perf_counter_read(child);
-
-	return total;
-}
-
-static int perf_counter_read_entry(struct perf_counter *counter,
-				   u64 read_format, char __user *buf)
-{
-	int n = 0, count = 0;
-	u64 values[2];
-
-	values[n++] = perf_counter_read_value(counter);
-	if (read_format & PERF_FORMAT_ID)
-		values[n++] = primary_counter_id(counter);
-
-	count = n * sizeof(u64);
-
-	if (copy_to_user(buf, values, count))
-		return -EFAULT;
-
-	return count;
-}
-
-static int perf_counter_read_group(struct perf_counter *counter,
-				   u64 read_format, char __user *buf)
-{
-	struct perf_counter *leader = counter->group_leader, *sub;
-	int n = 0, size = 0, err = -EFAULT;
-	u64 values[3];
-
-	values[n++] = 1 + leader->nr_siblings;
-	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
-		values[n++] = leader->total_time_enabled +
-			atomic64_read(&leader->child_total_time_enabled);
-	}
-	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
-		values[n++] = leader->total_time_running +
-			atomic64_read(&leader->child_total_time_running);
-	}
-
-	size = n * sizeof(u64);
-
-	if (copy_to_user(buf, values, size))
-		return -EFAULT;
-
-	err = perf_counter_read_entry(leader, read_format, buf + size);
-	if (err < 0)
-		return err;
-
-	size += err;
-
-	list_for_each_entry(sub, &leader->sibling_list, list_entry) {
-		err = perf_counter_read_entry(sub, read_format,
-				buf + size);
-		if (err < 0)
-			return err;
-
-		size += err;
-	}
-
-	return size;
-}
-
-static int perf_counter_read_one(struct perf_counter *counter,
-				 u64 read_format, char __user *buf)
-{
-	u64 values[4];
-	int n = 0;
-
-	values[n++] = perf_counter_read_value(counter);
-	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
-		values[n++] = counter->total_time_enabled +
-			atomic64_read(&counter->child_total_time_enabled);
-	}
-	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
-		values[n++] = counter->total_time_running +
-			atomic64_read(&counter->child_total_time_running);
-	}
-	if (read_format & PERF_FORMAT_ID)
-		values[n++] = primary_counter_id(counter);
-
-	if (copy_to_user(buf, values, n * sizeof(u64)))
-		return -EFAULT;
-
-	return n * sizeof(u64);
-}
-
-/*
- * Read the performance counter - simple non blocking version for now
- */
-static ssize_t
-perf_read_hw(struct perf_counter *counter, char __user *buf, size_t count)
-{
-	u64 read_format = counter->attr.read_format;
-	int ret;
-
-	/*
-	 * Return end-of-file for a read on a counter that is in
-	 * error state (i.e. because it was pinned but it couldn't be
-	 * scheduled on to the CPU at some point).
-	 */
-	if (counter->state == PERF_COUNTER_STATE_ERROR)
-		return 0;
-
-	if (count < perf_counter_read_size(counter))
-		return -ENOSPC;
-
-	WARN_ON_ONCE(counter->ctx->parent_ctx);
-	mutex_lock(&counter->child_mutex);
-	if (read_format & PERF_FORMAT_GROUP)
-		ret = perf_counter_read_group(counter, read_format, buf);
-	else
-		ret = perf_counter_read_one(counter, read_format, buf);
-	mutex_unlock(&counter->child_mutex);
-
-	return ret;
-}
-
-static ssize_t
-perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
-{
-	struct perf_counter *counter = file->private_data;
-
-	return perf_read_hw(counter, buf, count);
-}
-
-static unsigned int perf_poll(struct file *file, poll_table *wait)
-{
-	struct perf_counter *counter = file->private_data;
-	struct perf_mmap_data *data;
-	unsigned int events = POLL_HUP;
-
-	rcu_read_lock();
-	data = rcu_dereference(counter->data);
-	if (data)
-		events = atomic_xchg(&data->poll, 0);
-	rcu_read_unlock();
-
-	poll_wait(file, &counter->waitq, wait);
-
-	return events;
-}
-
-static void perf_counter_reset(struct perf_counter *counter)
-{
-	(void)perf_counter_read(counter);
-	atomic64_set(&counter->count, 0);
-	perf_counter_update_userpage(counter);
-}
-
-/*
- * Holding the top-level counter's child_mutex means that any
- * descendant process that has inherited this counter will block
- * in sync_child_counter if it goes to exit, thus satisfying the
- * task existence requirements of perf_counter_enable/disable.
- */
-static void perf_counter_for_each_child(struct perf_counter *counter,
-					void (*func)(struct perf_counter *))
-{
-	struct perf_counter *child;
-
-	WARN_ON_ONCE(counter->ctx->parent_ctx);
-	mutex_lock(&counter->child_mutex);
-	func(counter);
-	list_for_each_entry(child, &counter->child_list, child_list)
-		func(child);
-	mutex_unlock(&counter->child_mutex);
-}
-
-static void perf_counter_for_each(struct perf_counter *counter,
-				  void (*func)(struct perf_counter *))
-{
-	struct perf_counter_context *ctx = counter->ctx;
-	struct perf_counter *sibling;
-
-	WARN_ON_ONCE(ctx->parent_ctx);
-	mutex_lock(&ctx->mutex);
-	counter = counter->group_leader;
-
-	perf_counter_for_each_child(counter, func);
-	func(counter);
-	list_for_each_entry(sibling, &counter->sibling_list, list_entry)
-		perf_counter_for_each_child(counter, func);
-	mutex_unlock(&ctx->mutex);
-}
-
-static int perf_counter_period(struct perf_counter *counter, u64 __user *arg)
-{
-	struct perf_counter_context *ctx = counter->ctx;
-	unsigned long size;
-	int ret = 0;
-	u64 value;
-
-	if (!counter->attr.sample_period)
-		return -EINVAL;
-
-	size = copy_from_user(&value, arg, sizeof(value));
-	if (size != sizeof(value))
-		return -EFAULT;
-
-	if (!value)
-		return -EINVAL;
-
-	spin_lock_irq(&ctx->lock);
-	if (counter->attr.freq) {
-		if (value > sysctl_perf_counter_sample_rate) {
-			ret = -EINVAL;
-			goto unlock;
-		}
-
-		counter->attr.sample_freq = value;
-	} else {
-		counter->attr.sample_period = value;
-		counter->hw.sample_period = value;
-	}
-unlock:
-	spin_unlock_irq(&ctx->lock);
-
-	return ret;
-}
-
-static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
-{
-	struct perf_counter *counter = file->private_data;
-	void (*func)(struct perf_counter *);
-	u32 flags = arg;
-
-	switch (cmd) {
-	case PERF_COUNTER_IOC_ENABLE:
-		func = perf_counter_enable;
-		break;
-	case PERF_COUNTER_IOC_DISABLE:
-		func = perf_counter_disable;
-		break;
-	case PERF_COUNTER_IOC_RESET:
-		func = perf_counter_reset;
-		break;
-
-	case PERF_COUNTER_IOC_REFRESH:
-		return perf_counter_refresh(counter, arg);
-
-	case PERF_COUNTER_IOC_PERIOD:
-		return perf_counter_period(counter, (u64 __user *)arg);
-
-	default:
-		return -ENOTTY;
-	}
-
-	if (flags & PERF_IOC_FLAG_GROUP)
-		perf_counter_for_each(counter, func);
-	else
-		perf_counter_for_each_child(counter, func);
-
-	return 0;
-}
-
-int perf_counter_task_enable(void)
-{
-	struct perf_counter *counter;
-
-	mutex_lock(&current->perf_counter_mutex);
-	list_for_each_entry(counter, &current->perf_counter_list, owner_entry)
-		perf_counter_for_each_child(counter, perf_counter_enable);
-	mutex_unlock(&current->perf_counter_mutex);
-
-	return 0;
-}
-
-int perf_counter_task_disable(void)
-{
-	struct perf_counter *counter;
-
-	mutex_lock(&current->perf_counter_mutex);
-	list_for_each_entry(counter, &current->perf_counter_list, owner_entry)
-		perf_counter_for_each_child(counter, perf_counter_disable);
-	mutex_unlock(&current->perf_counter_mutex);
-
-	return 0;
-}
-
-#ifndef PERF_COUNTER_INDEX_OFFSET
-# define PERF_COUNTER_INDEX_OFFSET 0
-#endif
-
-static int perf_counter_index(struct perf_counter *counter)
-{
-	if (counter->state != PERF_COUNTER_STATE_ACTIVE)
-		return 0;
-
-	return counter->hw.idx + 1 - PERF_COUNTER_INDEX_OFFSET;
-}
-
-/*
- * Callers need to ensure there can be no nesting of this function, otherwise
- * the seqlock logic goes bad. We can not serialize this because the arch
- * code calls this from NMI context.
- */
-void perf_counter_update_userpage(struct perf_counter *counter)
-{
-	struct perf_counter_mmap_page *userpg;
-	struct perf_mmap_data *data;
-
-	rcu_read_lock();
-	data = rcu_dereference(counter->data);
-	if (!data)
-		goto unlock;
-
-	userpg = data->user_page;
-
-	/*
-	 * Disable preemption so as to not let the corresponding user-space
-	 * spin too long if we get preempted.
-	 */
-	preempt_disable();
-	++userpg->lock;
-	barrier();
-	userpg->index = perf_counter_index(counter);
-	userpg->offset = atomic64_read(&counter->count);
-	if (counter->state == PERF_COUNTER_STATE_ACTIVE)
-		userpg->offset -= atomic64_read(&counter->hw.prev_count);
-
-	userpg->time_enabled = counter->total_time_enabled +
-			atomic64_read(&counter->child_total_time_enabled);
-
-	userpg->time_running = counter->total_time_running +
-			atomic64_read(&counter->child_total_time_running);
-
-	barrier();
-	++userpg->lock;
-	preempt_enable();
-unlock:
-	rcu_read_unlock();
-}
-
-static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
-{
-	struct perf_counter *counter = vma->vm_file->private_data;
-	struct perf_mmap_data *data;
-	int ret = VM_FAULT_SIGBUS;
-
-	if (vmf->flags & FAULT_FLAG_MKWRITE) {
-		if (vmf->pgoff == 0)
-			ret = 0;
-		return ret;
-	}
-
-	rcu_read_lock();
-	data = rcu_dereference(counter->data);
-	if (!data)
-		goto unlock;
-
-	if (vmf->pgoff == 0) {
-		vmf->page = virt_to_page(data->user_page);
-	} else {
-		int nr = vmf->pgoff - 1;
-
-		if ((unsigned)nr > data->nr_pages)
-			goto unlock;
-
-		if (vmf->flags & FAULT_FLAG_WRITE)
-			goto unlock;
-
-		vmf->page = virt_to_page(data->data_pages[nr]);
-	}
-
-	get_page(vmf->page);
-	vmf->page->mapping = vma->vm_file->f_mapping;
-	vmf->page->index   = vmf->pgoff;
-
-	ret = 0;
-unlock:
-	rcu_read_unlock();
-
-	return ret;
-}
-
-static int perf_mmap_data_alloc(struct perf_counter *counter, int nr_pages)
-{
-	struct perf_mmap_data *data;
-	unsigned long size;
-	int i;
-
-	WARN_ON(atomic_read(&counter->mmap_count));
-
-	size = sizeof(struct perf_mmap_data);
-	size += nr_pages * sizeof(void *);
-
-	data = kzalloc(size, GFP_KERNEL);
-	if (!data)
-		goto fail;
-
-	data->user_page = (void *)get_zeroed_page(GFP_KERNEL);
-	if (!data->user_page)
-		goto fail_user_page;
-
-	for (i = 0; i < nr_pages; i++) {
-		data->data_pages[i] = (void *)get_zeroed_page(GFP_KERNEL);
-		if (!data->data_pages[i])
-			goto fail_data_pages;
-	}
-
-	data->nr_pages = nr_pages;
-	atomic_set(&data->lock, -1);
-
-	rcu_assign_pointer(counter->data, data);
-
-	return 0;
-
-fail_data_pages:
-	for (i--; i >= 0; i--)
-		free_page((unsigned long)data->data_pages[i]);
-
-	free_page((unsigned long)data->user_page);
-
-fail_user_page:
-	kfree(data);
-
-fail:
-	return -ENOMEM;
-}
-
-static void perf_mmap_free_page(unsigned long addr)
-{
-	struct page *page = virt_to_page((void *)addr);
-
-	page->mapping = NULL;
-	__free_page(page);
-}
-
-static void __perf_mmap_data_free(struct rcu_head *rcu_head)
-{
-	struct perf_mmap_data *data;
-	int i;
-
-	data = container_of(rcu_head, struct perf_mmap_data, rcu_head);
-
-	perf_mmap_free_page((unsigned long)data->user_page);
-	for (i = 0; i < data->nr_pages; i++)
-		perf_mmap_free_page((unsigned long)data->data_pages[i]);
-
-	kfree(data);
-}
-
-static void perf_mmap_data_free(struct perf_counter *counter)
-{
-	struct perf_mmap_data *data = counter->data;
-
-	WARN_ON(atomic_read(&counter->mmap_count));
-
-	rcu_assign_pointer(counter->data, NULL);
-	call_rcu(&data->rcu_head, __perf_mmap_data_free);
-}
-
-static void perf_mmap_open(struct vm_area_struct *vma)
-{
-	struct perf_counter *counter = vma->vm_file->private_data;
-
-	atomic_inc(&counter->mmap_count);
-}
-
-static void perf_mmap_close(struct vm_area_struct *vma)
-{
-	struct perf_counter *counter = vma->vm_file->private_data;
-
-	WARN_ON_ONCE(counter->ctx->parent_ctx);
-	if (atomic_dec_and_mutex_lock(&counter->mmap_count, &counter->mmap_mutex)) {
-		struct user_struct *user = current_user();
-
-		atomic_long_sub(counter->data->nr_pages + 1, &user->locked_vm);
-		vma->vm_mm->locked_vm -= counter->data->nr_locked;
-		perf_mmap_data_free(counter);
-		mutex_unlock(&counter->mmap_mutex);
-	}
-}
-
-static struct vm_operations_struct perf_mmap_vmops = {
-	.open		= perf_mmap_open,
-	.close		= perf_mmap_close,
-	.fault		= perf_mmap_fault,
-	.page_mkwrite	= perf_mmap_fault,
-};
-
-static int perf_mmap(struct file *file, struct vm_area_struct *vma)
-{
-	struct perf_counter *counter = file->private_data;
-	unsigned long user_locked, user_lock_limit;
-	struct user_struct *user = current_user();
-	unsigned long locked, lock_limit;
-	unsigned long vma_size;
-	unsigned long nr_pages;
-	long user_extra, extra;
-	int ret = 0;
-
-	if (!(vma->vm_flags & VM_SHARED))
-		return -EINVAL;
-
-	vma_size = vma->vm_end - vma->vm_start;
-	nr_pages = (vma_size / PAGE_SIZE) - 1;
-
-	/*
-	 * If we have data pages ensure they're a power-of-two number, so we
-	 * can do bitmasks instead of modulo.
-	 */
-	if (nr_pages != 0 && !is_power_of_2(nr_pages))
-		return -EINVAL;
-
-	if (vma_size != PAGE_SIZE * (1 + nr_pages))
-		return -EINVAL;
-
-	if (vma->vm_pgoff != 0)
-		return -EINVAL;
-
-	WARN_ON_ONCE(counter->ctx->parent_ctx);
-	mutex_lock(&counter->mmap_mutex);
-	if (atomic_inc_not_zero(&counter->mmap_count)) {
-		if (nr_pages != counter->data->nr_pages)
-			ret = -EINVAL;
-		goto unlock;
-	}
-
-	user_extra = nr_pages + 1;
-	user_lock_limit = sysctl_perf_counter_mlock >> (PAGE_SHIFT - 10);
-
-	/*
-	 * Increase the limit linearly with more CPUs:
-	 */
-	user_lock_limit *= num_online_cpus();
-
-	user_locked = atomic_long_read(&user->locked_vm) + user_extra;
-
-	extra = 0;
-	if (user_locked > user_lock_limit)
-		extra = user_locked - user_lock_limit;
-
-	lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
-	lock_limit >>= PAGE_SHIFT;
-	locked = vma->vm_mm->locked_vm + extra;
-
-	if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) {
-		ret = -EPERM;
-		goto unlock;
-	}
-
-	WARN_ON(counter->data);
-	ret = perf_mmap_data_alloc(counter, nr_pages);
-	if (ret)
-		goto unlock;
-
-	atomic_set(&counter->mmap_count, 1);
-	atomic_long_add(user_extra, &user->locked_vm);
-	vma->vm_mm->locked_vm += extra;
-	counter->data->nr_locked = extra;
-	if (vma->vm_flags & VM_WRITE)
-		counter->data->writable = 1;
-
-unlock:
-	mutex_unlock(&counter->mmap_mutex);
-
-	vma->vm_flags |= VM_RESERVED;
-	vma->vm_ops = &perf_mmap_vmops;
-
-	return ret;
-}
-
-static int perf_fasync(int fd, struct file *filp, int on)
-{
-	struct inode *inode = filp->f_path.dentry->d_inode;
-	struct perf_counter *counter = filp->private_data;
-	int retval;
-
-	mutex_lock(&inode->i_mutex);
-	retval = fasync_helper(fd, filp, on, &counter->fasync);
-	mutex_unlock(&inode->i_mutex);
-
-	if (retval < 0)
-		return retval;
-
-	return 0;
-}
-
-static const struct file_operations perf_fops = {
-	.release		= perf_release,
-	.read			= perf_read,
-	.poll			= perf_poll,
-	.unlocked_ioctl		= perf_ioctl,
-	.compat_ioctl		= perf_ioctl,
-	.mmap			= perf_mmap,
-	.fasync			= perf_fasync,
-};
-
-/*
- * Perf counter wakeup
- *
- * If there's data, ensure we set the poll() state and publish everything
- * to user-space before waking everybody up.
- */
-
-void perf_counter_wakeup(struct perf_counter *counter)
-{
-	wake_up_all(&counter->waitq);
-
-	if (counter->pending_kill) {
-		kill_fasync(&counter->fasync, SIGIO, counter->pending_kill);
-		counter->pending_kill = 0;
-	}
-}
-
-/*
- * Pending wakeups
- *
- * Handle the case where we need to wakeup up from NMI (or rq->lock) context.
- *
- * The NMI bit means we cannot possibly take locks. Therefore, maintain a
- * single linked list and use cmpxchg() to add entries lockless.
- */
-
-static void perf_pending_counter(struct perf_pending_entry *entry)
-{
-	struct perf_counter *counter = container_of(entry,
-			struct perf_counter, pending);
-
-	if (counter->pending_disable) {
-		counter->pending_disable = 0;
-		__perf_counter_disable(counter);
-	}
-
-	if (counter->pending_wakeup) {
-		counter->pending_wakeup = 0;
-		perf_counter_wakeup(counter);
-	}
-}
-
-#define PENDING_TAIL ((struct perf_pending_entry *)-1UL)
-
-static DEFINE_PER_CPU(struct perf_pending_entry *, perf_pending_head) = {
-	PENDING_TAIL,
-};
-
-static void perf_pending_queue(struct perf_pending_entry *entry,
-			       void (*func)(struct perf_pending_entry *))
-{
-	struct perf_pending_entry **head;
-
-	if (cmpxchg(&entry->next, NULL, PENDING_TAIL) != NULL)
-		return;
-
-	entry->func = func;
-
-	head = &get_cpu_var(perf_pending_head);
-
-	do {
-		entry->next = *head;
-	} while (cmpxchg(head, entry->next, entry) != entry->next);
-
-	set_perf_counter_pending();
-
-	put_cpu_var(perf_pending_head);
-}
-
-static int __perf_pending_run(void)
-{
-	struct perf_pending_entry *list;
-	int nr = 0;
-
-	list = xchg(&__get_cpu_var(perf_pending_head), PENDING_TAIL);
-	while (list != PENDING_TAIL) {
-		void (*func)(struct perf_pending_entry *);
-		struct perf_pending_entry *entry = list;
-
-		list = list->next;
-
-		func = entry->func;
-		entry->next = NULL;
-		/*
-		 * Ensure we observe the unqueue before we issue the wakeup,
-		 * so that we won't be waiting forever.
-		 * -- see perf_not_pending().
-		 */
-		smp_wmb();
-
-		func(entry);
-		nr++;
-	}
-
-	return nr;
-}
-
-static inline int perf_not_pending(struct perf_counter *counter)
-{
-	/*
-	 * If we flush on whatever cpu we run, there is a chance we don't
-	 * need to wait.
-	 */
-	get_cpu();
-	__perf_pending_run();
-	put_cpu();
-
-	/*
-	 * Ensure we see the proper queue state before going to sleep
-	 * so that we do not miss the wakeup. -- see perf_pending_handle()
-	 */
-	smp_rmb();
-	return counter->pending.next == NULL;
-}
-
-static void perf_pending_sync(struct perf_counter *counter)
-{
-	wait_event(counter->waitq, perf_not_pending(counter));
-}
-
-void perf_counter_do_pending(void)
-{
-	__perf_pending_run();
-}
-
-/*
- * Callchain support -- arch specific
- */
-
-__weak struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
-{
-	return NULL;
-}
-
-/*
- * Output
- */
-
-struct perf_output_handle {
-	struct perf_counter	*counter;
-	struct perf_mmap_data	*data;
-	unsigned long		head;
-	unsigned long		offset;
-	int			nmi;
-	int			sample;
-	int			locked;
-	unsigned long		flags;
-};
-
-static bool perf_output_space(struct perf_mmap_data *data,
-			      unsigned int offset, unsigned int head)
-{
-	unsigned long tail;
-	unsigned long mask;
-
-	if (!data->writable)
-		return true;
-
-	mask = (data->nr_pages << PAGE_SHIFT) - 1;
-	/*
-	 * Userspace could choose to issue a mb() before updating the tail
-	 * pointer. So that all reads will be completed before the write is
-	 * issued.
-	 */
-	tail = ACCESS_ONCE(data->user_page->data_tail);
-	smp_rmb();
-
-	offset = (offset - tail) & mask;
-	head   = (head   - tail) & mask;
-
-	if ((int)(head - offset) < 0)
-		return false;
-
-	return true;
-}
-
-static void perf_output_wakeup(struct perf_output_handle *handle)
-{
-	atomic_set(&handle->data->poll, POLL_IN);
-
-	if (handle->nmi) {
-		handle->counter->pending_wakeup = 1;
-		perf_pending_queue(&handle->counter->pending,
-				   perf_pending_counter);
-	} else
-		perf_counter_wakeup(handle->counter);
-}
-
-/*
- * Curious locking construct.
- *
- * We need to ensure a later event doesn't publish a head when a former
- * event isn't done writing. However since we need to deal with NMIs we
- * cannot fully serialize things.
- *
- * What we do is serialize between CPUs so we only have to deal with NMI
- * nesting on a single CPU.
- *
- * We only publish the head (and generate a wakeup) when the outer-most
- * event completes.
- */
-static void perf_output_lock(struct perf_output_handle *handle)
-{
-	struct perf_mmap_data *data = handle->data;
-	int cpu;
-
-	handle->locked = 0;
-
-	local_irq_save(handle->flags);
-	cpu = smp_processor_id();
-
-	if (in_nmi() && atomic_read(&data->lock) == cpu)
-		return;
-
-	while (atomic_cmpxchg(&data->lock, -1, cpu) != -1)
-		cpu_relax();
-
-	handle->locked = 1;
-}
-
-static void perf_output_unlock(struct perf_output_handle *handle)
-{
-	struct perf_mmap_data *data = handle->data;
-	unsigned long head;
-	int cpu;
-
-	data->done_head = data->head;
-
-	if (!handle->locked)
-		goto out;
-
-again:
-	/*
-	 * The xchg implies a full barrier that ensures all writes are done
-	 * before we publish the new head, matched by a rmb() in userspace when
-	 * reading this position.
-	 */
-	while ((head = atomic_long_xchg(&data->done_head, 0)))
-		data->user_page->data_head = head;
-
-	/*
-	 * NMI can happen here, which means we can miss a done_head update.
-	 */
-
-	cpu = atomic_xchg(&data->lock, -1);
-	WARN_ON_ONCE(cpu != smp_processor_id());
-
-	/*
-	 * Therefore we have to validate we did not indeed do so.
-	 */
-	if (unlikely(atomic_long_read(&data->done_head))) {
-		/*
-		 * Since we had it locked, we can lock it again.
-		 */
-		while (atomic_cmpxchg(&data->lock, -1, cpu) != -1)
-			cpu_relax();
-
-		goto again;
-	}
-
-	if (atomic_xchg(&data->wakeup, 0))
-		perf_output_wakeup(handle);
-out:
-	local_irq_restore(handle->flags);
-}
-
-static void perf_output_copy(struct perf_output_handle *handle,
-			     const void *buf, unsigned int len)
-{
-	unsigned int pages_mask;
-	unsigned int offset;
-	unsigned int size;
-	void **pages;
-
-	offset		= handle->offset;
-	pages_mask	= handle->data->nr_pages - 1;
-	pages		= handle->data->data_pages;
-
-	do {
-		unsigned int page_offset;
-		int nr;
-
-		nr	    = (offset >> PAGE_SHIFT) & pages_mask;
-		page_offset = offset & (PAGE_SIZE - 1);
-		size	    = min_t(unsigned int, PAGE_SIZE - page_offset, len);
-
-		memcpy(pages[nr] + page_offset, buf, size);
-
-		len	    -= size;
-		buf	    += size;
-		offset	    += size;
-	} while (len);
-
-	handle->offset = offset;
-
-	/*
-	 * Check we didn't copy past our reservation window, taking the
-	 * possible unsigned int wrap into account.
-	 */
-	WARN_ON_ONCE(((long)(handle->head - handle->offset)) < 0);
-}
-
-#define perf_output_put(handle, x) \
-	perf_output_copy((handle), &(x), sizeof(x))
-
-static int perf_output_begin(struct perf_output_handle *handle,
-			     struct perf_counter *counter, unsigned int size,
-			     int nmi, int sample)
-{
-	struct perf_mmap_data *data;
-	unsigned int offset, head;
-	int have_lost;
-	struct {
-		struct perf_event_header header;
-		u64			 id;
-		u64			 lost;
-	} lost_event;
-
-	/*
-	 * For inherited counters we send all the output towards the parent.
-	 */
-	if (counter->parent)
-		counter = counter->parent;
-
-	rcu_read_lock();
-	data = rcu_dereference(counter->data);
-	if (!data)
-		goto out;
-
-	handle->data	= data;
-	handle->counter	= counter;
-	handle->nmi	= nmi;
-	handle->sample	= sample;
-
-	if (!data->nr_pages)
-		goto fail;
-
-	have_lost = atomic_read(&data->lost);
-	if (have_lost)
-		size += sizeof(lost_event);
-
-	perf_output_lock(handle);
-
-	do {
-		offset = head = atomic_long_read(&data->head);
-		head += size;
-		if (unlikely(!perf_output_space(data, offset, head)))
-			goto fail;
-	} while (atomic_long_cmpxchg(&data->head, offset, head) != offset);
-
-	handle->offset	= offset;
-	handle->head	= head;
-
-	if ((offset >> PAGE_SHIFT) != (head >> PAGE_SHIFT))
-		atomic_set(&data->wakeup, 1);
-
-	if (have_lost) {
-		lost_event.header.type = PERF_EVENT_LOST;
-		lost_event.header.misc = 0;
-		lost_event.header.size = sizeof(lost_event);
-		lost_event.id          = counter->id;
-		lost_event.lost        = atomic_xchg(&data->lost, 0);
-
-		perf_output_put(handle, lost_event);
-	}
-
-	return 0;
-
-fail:
-	atomic_inc(&data->lost);
-	perf_output_unlock(handle);
-out:
-	rcu_read_unlock();
-
-	return -ENOSPC;
-}
-
-static void perf_output_end(struct perf_output_handle *handle)
-{
-	struct perf_counter *counter = handle->counter;
-	struct perf_mmap_data *data = handle->data;
-
-	int wakeup_events = counter->attr.wakeup_events;
-
-	if (handle->sample && wakeup_events) {
-		int events = atomic_inc_return(&data->events);
-		if (events >= wakeup_events) {
-			atomic_sub(wakeup_events, &data->events);
-			atomic_set(&data->wakeup, 1);
-		}
-	}
-
-	perf_output_unlock(handle);
-	rcu_read_unlock();
-}
-
-static u32 perf_counter_pid(struct perf_counter *counter, struct task_struct *p)
-{
-	/*
-	 * only top level counters have the pid namespace they were created in
-	 */
-	if (counter->parent)
-		counter = counter->parent;
-
-	return task_tgid_nr_ns(p, counter->ns);
-}
-
-static u32 perf_counter_tid(struct perf_counter *counter, struct task_struct *p)
-{
-	/*
-	 * only top level counters have the pid namespace they were created in
-	 */
-	if (counter->parent)
-		counter = counter->parent;
-
-	return task_pid_nr_ns(p, counter->ns);
-}
-
-static void perf_output_read_one(struct perf_output_handle *handle,
-				 struct perf_counter *counter)
-{
-	u64 read_format = counter->attr.read_format;
-	u64 values[4];
-	int n = 0;
-
-	values[n++] = atomic64_read(&counter->count);
-	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
-		values[n++] = counter->total_time_enabled +
-			atomic64_read(&counter->child_total_time_enabled);
-	}
-	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
-		values[n++] = counter->total_time_running +
-			atomic64_read(&counter->child_total_time_running);
-	}
-	if (read_format & PERF_FORMAT_ID)
-		values[n++] = primary_counter_id(counter);
-
-	perf_output_copy(handle, values, n * sizeof(u64));
-}
-
-/*
- * XXX PERF_FORMAT_GROUP vs inherited counters seems difficult.
- */
-static void perf_output_read_group(struct perf_output_handle *handle,
-			    struct perf_counter *counter)
-{
-	struct perf_counter *leader = counter->group_leader, *sub;
-	u64 read_format = counter->attr.read_format;
-	u64 values[5];
-	int n = 0;
-
-	values[n++] = 1 + leader->nr_siblings;
-
-	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
-		values[n++] = leader->total_time_enabled;
-
-	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
-		values[n++] = leader->total_time_running;
-
-	if (leader != counter)
-		leader->pmu->read(leader);
-
-	values[n++] = atomic64_read(&leader->count);
-	if (read_format & PERF_FORMAT_ID)
-		values[n++] = primary_counter_id(leader);
-
-	perf_output_copy(handle, values, n * sizeof(u64));
-
-	list_for_each_entry(sub, &leader->sibling_list, list_entry) {
-		n = 0;
-
-		if (sub != counter)
-			sub->pmu->read(sub);
-
-		values[n++] = atomic64_read(&sub->count);
-		if (read_format & PERF_FORMAT_ID)
-			values[n++] = primary_counter_id(sub);
-
-		perf_output_copy(handle, values, n * sizeof(u64));
-	}
-}
-
-static void perf_output_read(struct perf_output_handle *handle,
-			     struct perf_counter *counter)
-{
-	if (counter->attr.read_format & PERF_FORMAT_GROUP)
-		perf_output_read_group(handle, counter);
-	else
-		perf_output_read_one(handle, counter);
-}
-
-void perf_counter_output(struct perf_counter *counter, int nmi,
-				struct perf_sample_data *data)
-{
-	int ret;
-	u64 sample_type = counter->attr.sample_type;
-	struct perf_output_handle handle;
-	struct perf_event_header header;
-	u64 ip;
-	struct {
-		u32 pid, tid;
-	} tid_entry;
-	struct perf_callchain_entry *callchain = NULL;
-	int callchain_size = 0;
-	u64 time;
-	struct {
-		u32 cpu, reserved;
-	} cpu_entry;
-
-	header.type = PERF_EVENT_SAMPLE;
-	header.size = sizeof(header);
-
-	header.misc = 0;
-	header.misc |= perf_misc_flags(data->regs);
-
-	if (sample_type & PERF_SAMPLE_IP) {
-		ip = perf_instruction_pointer(data->regs);
-		header.size += sizeof(ip);
-	}
-
-	if (sample_type & PERF_SAMPLE_TID) {
-		/* namespace issues */
-		tid_entry.pid = perf_counter_pid(counter, current);
-		tid_entry.tid = perf_counter_tid(counter, current);
-
-		header.size += sizeof(tid_entry);
-	}
-
-	if (sample_type & PERF_SAMPLE_TIME) {
-		/*
-		 * Maybe do better on x86 and provide cpu_clock_nmi()
-		 */
-		time = sched_clock();
-
-		header.size += sizeof(u64);
-	}
-
-	if (sample_type & PERF_SAMPLE_ADDR)
-		header.size += sizeof(u64);
-
-	if (sample_type & PERF_SAMPLE_ID)
-		header.size += sizeof(u64);
-
-	if (sample_type & PERF_SAMPLE_STREAM_ID)
-		header.size += sizeof(u64);
-
-	if (sample_type & PERF_SAMPLE_CPU) {
-		header.size += sizeof(cpu_entry);
-
-		cpu_entry.cpu = raw_smp_processor_id();
-		cpu_entry.reserved = 0;
-	}
-
-	if (sample_type & PERF_SAMPLE_PERIOD)
-		header.size += sizeof(u64);
-
-	if (sample_type & PERF_SAMPLE_READ)
-		header.size += perf_counter_read_size(counter);
-
-	if (sample_type & PERF_SAMPLE_CALLCHAIN) {
-		callchain = perf_callchain(data->regs);
-
-		if (callchain) {
-			callchain_size = (1 + callchain->nr) * sizeof(u64);
-			header.size += callchain_size;
-		} else
-			header.size += sizeof(u64);
-	}
-
-	if (sample_type & PERF_SAMPLE_RAW) {
-		int size = sizeof(u32);
-
-		if (data->raw)
-			size += data->raw->size;
-		else
-			size += sizeof(u32);
-
-		WARN_ON_ONCE(size & (sizeof(u64)-1));
-		header.size += size;
-	}
-
-	ret = perf_output_begin(&handle, counter, header.size, nmi, 1);
-	if (ret)
-		return;
-
-	perf_output_put(&handle, header);
-
-	if (sample_type & PERF_SAMPLE_IP)
-		perf_output_put(&handle, ip);
-
-	if (sample_type & PERF_SAMPLE_TID)
-		perf_output_put(&handle, tid_entry);
-
-	if (sample_type & PERF_SAMPLE_TIME)
-		perf_output_put(&handle, time);
-
-	if (sample_type & PERF_SAMPLE_ADDR)
-		perf_output_put(&handle, data->addr);
-
-	if (sample_type & PERF_SAMPLE_ID) {
-		u64 id = primary_counter_id(counter);
-
-		perf_output_put(&handle, id);
-	}
-
-	if (sample_type & PERF_SAMPLE_STREAM_ID)
-		perf_output_put(&handle, counter->id);
-
-	if (sample_type & PERF_SAMPLE_CPU)
-		perf_output_put(&handle, cpu_entry);
-
-	if (sample_type & PERF_SAMPLE_PERIOD)
-		perf_output_put(&handle, data->period);
-
-	if (sample_type & PERF_SAMPLE_READ)
-		perf_output_read(&handle, counter);
-
-	if (sample_type & PERF_SAMPLE_CALLCHAIN) {
-		if (callchain)
-			perf_output_copy(&handle, callchain, callchain_size);
-		else {
-			u64 nr = 0;
-			perf_output_put(&handle, nr);
-		}
-	}
-
-	if (sample_type & PERF_SAMPLE_RAW) {
-		if (data->raw) {
-			perf_output_put(&handle, data->raw->size);
-			perf_output_copy(&handle, data->raw->data, data->raw->size);
-		} else {
-			struct {
-				u32	size;
-				u32	data;
-			} raw = {
-				.size = sizeof(u32),
-				.data = 0,
-			};
-			perf_output_put(&handle, raw);
-		}
-	}
-
-	perf_output_end(&handle);
-}
-
-/*
- * read event
- */
-
-struct perf_read_event {
-	struct perf_event_header	header;
-
-	u32				pid;
-	u32				tid;
-};
-
-static void
-perf_counter_read_event(struct perf_counter *counter,
-			struct task_struct *task)
-{
-	struct perf_output_handle handle;
-	struct perf_read_event event = {
-		.header = {
-			.type = PERF_EVENT_READ,
-			.misc = 0,
-			.size = sizeof(event) + perf_counter_read_size(counter),
-		},
-		.pid = perf_counter_pid(counter, task),
-		.tid = perf_counter_tid(counter, task),
-	};
-	int ret;
-
-	ret = perf_output_begin(&handle, counter, event.header.size, 0, 0);
-	if (ret)
-		return;
-
-	perf_output_put(&handle, event);
-	perf_output_read(&handle, counter);
-
-	perf_output_end(&handle);
-}
-
-/*
- * task tracking -- fork/exit
- *
- * enabled by: attr.comm | attr.mmap | attr.task
- */
-
-struct perf_task_event {
-	struct task_struct		*task;
-	struct perf_counter_context	*task_ctx;
-
-	struct {
-		struct perf_event_header	header;
-
-		u32				pid;
-		u32				ppid;
-		u32				tid;
-		u32				ptid;
-	} event;
-};
-
-static void perf_counter_task_output(struct perf_counter *counter,
-				     struct perf_task_event *task_event)
-{
-	struct perf_output_handle handle;
-	int size = task_event->event.header.size;
-	struct task_struct *task = task_event->task;
-	int ret = perf_output_begin(&handle, counter, size, 0, 0);
-
-	if (ret)
-		return;
-
-	task_event->event.pid = perf_counter_pid(counter, task);
-	task_event->event.ppid = perf_counter_pid(counter, current);
-
-	task_event->event.tid = perf_counter_tid(counter, task);
-	task_event->event.ptid = perf_counter_tid(counter, current);
-
-	perf_output_put(&handle, task_event->event);
-	perf_output_end(&handle);
-}
-
-static int perf_counter_task_match(struct perf_counter *counter)
-{
-	if (counter->attr.comm || counter->attr.mmap || counter->attr.task)
-		return 1;
-
-	return 0;
-}
-
-static void perf_counter_task_ctx(struct perf_counter_context *ctx,
-				  struct perf_task_event *task_event)
-{
-	struct perf_counter *counter;
-
-	if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
-		return;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(counter, &ctx->event_list, event_entry) {
-		if (perf_counter_task_match(counter))
-			perf_counter_task_output(counter, task_event);
-	}
-	rcu_read_unlock();
-}
-
-static void perf_counter_task_event(struct perf_task_event *task_event)
-{
-	struct perf_cpu_context *cpuctx;
-	struct perf_counter_context *ctx = task_event->task_ctx;
-
-	cpuctx = &get_cpu_var(perf_cpu_context);
-	perf_counter_task_ctx(&cpuctx->ctx, task_event);
-	put_cpu_var(perf_cpu_context);
-
-	rcu_read_lock();
-	if (!ctx)
-		ctx = rcu_dereference(task_event->task->perf_counter_ctxp);
-	if (ctx)
-		perf_counter_task_ctx(ctx, task_event);
-	rcu_read_unlock();
-}
-
-static void perf_counter_task(struct task_struct *task,
-			      struct perf_counter_context *task_ctx,
-			      int new)
-{
-	struct perf_task_event task_event;
-
-	if (!atomic_read(&nr_comm_counters) &&
-	    !atomic_read(&nr_mmap_counters) &&
-	    !atomic_read(&nr_task_counters))
-		return;
-
-	task_event = (struct perf_task_event){
-		.task	  = task,
-		.task_ctx = task_ctx,
-		.event    = {
-			.header = {
-				.type = new ? PERF_EVENT_FORK : PERF_EVENT_EXIT,
-				.misc = 0,
-				.size = sizeof(task_event.event),
-			},
-			/* .pid  */
-			/* .ppid */
-			/* .tid  */
-			/* .ptid */
-		},
-	};
-
-	perf_counter_task_event(&task_event);
-}
-
-void perf_counter_fork(struct task_struct *task)
-{
-	perf_counter_task(task, NULL, 1);
-}
-
-/*
- * comm tracking
- */
-
-struct perf_comm_event {
-	struct task_struct	*task;
-	char			*comm;
-	int			comm_size;
-
-	struct {
-		struct perf_event_header	header;
-
-		u32				pid;
-		u32				tid;
-	} event;
-};
-
-static void perf_counter_comm_output(struct perf_counter *counter,
-				     struct perf_comm_event *comm_event)
-{
-	struct perf_output_handle handle;
-	int size = comm_event->event.header.size;
-	int ret = perf_output_begin(&handle, counter, size, 0, 0);
-
-	if (ret)
-		return;
-
-	comm_event->event.pid = perf_counter_pid(counter, comm_event->task);
-	comm_event->event.tid = perf_counter_tid(counter, comm_event->task);
-
-	perf_output_put(&handle, comm_event->event);
-	perf_output_copy(&handle, comm_event->comm,
-				   comm_event->comm_size);
-	perf_output_end(&handle);
-}
-
-static int perf_counter_comm_match(struct perf_counter *counter)
-{
-	if (counter->attr.comm)
-		return 1;
-
-	return 0;
-}
-
-static void perf_counter_comm_ctx(struct perf_counter_context *ctx,
-				  struct perf_comm_event *comm_event)
-{
-	struct perf_counter *counter;
-
-	if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
-		return;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(counter, &ctx->event_list, event_entry) {
-		if (perf_counter_comm_match(counter))
-			perf_counter_comm_output(counter, comm_event);
-	}
-	rcu_read_unlock();
-}
-
-static void perf_counter_comm_event(struct perf_comm_event *comm_event)
-{
-	struct perf_cpu_context *cpuctx;
-	struct perf_counter_context *ctx;
-	unsigned int size;
-	char comm[TASK_COMM_LEN];
-
-	memset(comm, 0, sizeof(comm));
-	strncpy(comm, comm_event->task->comm, sizeof(comm));
-	size = ALIGN(strlen(comm)+1, sizeof(u64));
-
-	comm_event->comm = comm;
-	comm_event->comm_size = size;
-
-	comm_event->event.header.size = sizeof(comm_event->event) + size;
-
-	cpuctx = &get_cpu_var(perf_cpu_context);
-	perf_counter_comm_ctx(&cpuctx->ctx, comm_event);
-	put_cpu_var(perf_cpu_context);
-
-	rcu_read_lock();
-	/*
-	 * doesn't really matter which of the child contexts the
-	 * events ends up in.
-	 */
-	ctx = rcu_dereference(current->perf_counter_ctxp);
-	if (ctx)
-		perf_counter_comm_ctx(ctx, comm_event);
-	rcu_read_unlock();
-}
-
-void perf_counter_comm(struct task_struct *task)
-{
-	struct perf_comm_event comm_event;
-
-	if (task->perf_counter_ctxp)
-		perf_counter_enable_on_exec(task);
-
-	if (!atomic_read(&nr_comm_counters))
-		return;
-
-	comm_event = (struct perf_comm_event){
-		.task	= task,
-		/* .comm      */
-		/* .comm_size */
-		.event  = {
-			.header = {
-				.type = PERF_EVENT_COMM,
-				.misc = 0,
-				/* .size */
-			},
-			/* .pid */
-			/* .tid */
-		},
-	};
-
-	perf_counter_comm_event(&comm_event);
-}
-
-/*
- * mmap tracking
- */
-
-struct perf_mmap_event {
-	struct vm_area_struct	*vma;
-
-	const char		*file_name;
-	int			file_size;
-
-	struct {
-		struct perf_event_header	header;
-
-		u32				pid;
-		u32				tid;
-		u64				start;
-		u64				len;
-		u64				pgoff;
-	} event;
-};
-
-static void perf_counter_mmap_output(struct perf_counter *counter,
-				     struct perf_mmap_event *mmap_event)
-{
-	struct perf_output_handle handle;
-	int size = mmap_event->event.header.size;
-	int ret = perf_output_begin(&handle, counter, size, 0, 0);
-
-	if (ret)
-		return;
-
-	mmap_event->event.pid = perf_counter_pid(counter, current);
-	mmap_event->event.tid = perf_counter_tid(counter, current);
-
-	perf_output_put(&handle, mmap_event->event);
-	perf_output_copy(&handle, mmap_event->file_name,
-				   mmap_event->file_size);
-	perf_output_end(&handle);
-}
-
-static int perf_counter_mmap_match(struct perf_counter *counter,
-				   struct perf_mmap_event *mmap_event)
-{
-	if (counter->attr.mmap)
-		return 1;
-
-	return 0;
-}
-
-static void perf_counter_mmap_ctx(struct perf_counter_context *ctx,
-				  struct perf_mmap_event *mmap_event)
-{
-	struct perf_counter *counter;
-
-	if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
-		return;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(counter, &ctx->event_list, event_entry) {
-		if (perf_counter_mmap_match(counter, mmap_event))
-			perf_counter_mmap_output(counter, mmap_event);
-	}
-	rcu_read_unlock();
-}
-
-static void perf_counter_mmap_event(struct perf_mmap_event *mmap_event)
-{
-	struct perf_cpu_context *cpuctx;
-	struct perf_counter_context *ctx;
-	struct vm_area_struct *vma = mmap_event->vma;
-	struct file *file = vma->vm_file;
-	unsigned int size;
-	char tmp[16];
-	char *buf = NULL;
-	const char *name;
-
-	memset(tmp, 0, sizeof(tmp));
-
-	if (file) {
-		/*
-		 * d_path works from the end of the buffer backwards, so we
-		 * need to add enough zero bytes after the string to handle
-		 * the 64bit alignment we do later.
-		 */
-		buf = kzalloc(PATH_MAX + sizeof(u64), GFP_KERNEL);
-		if (!buf) {
-			name = strncpy(tmp, "//enomem", sizeof(tmp));
-			goto got_name;
-		}
-		name = d_path(&file->f_path, buf, PATH_MAX);
-		if (IS_ERR(name)) {
-			name = strncpy(tmp, "//toolong", sizeof(tmp));
-			goto got_name;
-		}
-	} else {
-		if (arch_vma_name(mmap_event->vma)) {
-			name = strncpy(tmp, arch_vma_name(mmap_event->vma),
-				       sizeof(tmp));
-			goto got_name;
-		}
-
-		if (!vma->vm_mm) {
-			name = strncpy(tmp, "[vdso]", sizeof(tmp));
-			goto got_name;
-		}
-
-		name = strncpy(tmp, "//anon", sizeof(tmp));
-		goto got_name;
-	}
-
-got_name:
-	size = ALIGN(strlen(name)+1, sizeof(u64));
-
-	mmap_event->file_name = name;
-	mmap_event->file_size = size;
-
-	mmap_event->event.header.size = sizeof(mmap_event->event) + size;
-
-	cpuctx = &get_cpu_var(perf_cpu_context);
-	perf_counter_mmap_ctx(&cpuctx->ctx, mmap_event);
-	put_cpu_var(perf_cpu_context);
-
-	rcu_read_lock();
-	/*
-	 * doesn't really matter which of the child contexts the
-	 * events ends up in.
-	 */
-	ctx = rcu_dereference(current->perf_counter_ctxp);
-	if (ctx)
-		perf_counter_mmap_ctx(ctx, mmap_event);
-	rcu_read_unlock();
-
-	kfree(buf);
-}
-
-void __perf_counter_mmap(struct vm_area_struct *vma)
-{
-	struct perf_mmap_event mmap_event;
-
-	if (!atomic_read(&nr_mmap_counters))
-		return;
-
-	mmap_event = (struct perf_mmap_event){
-		.vma	= vma,
-		/* .file_name */
-		/* .file_size */
-		.event  = {
-			.header = {
-				.type = PERF_EVENT_MMAP,
-				.misc = 0,
-				/* .size */
-			},
-			/* .pid */
-			/* .tid */
-			.start  = vma->vm_start,
-			.len    = vma->vm_end - vma->vm_start,
-			.pgoff  = vma->vm_pgoff,
-		},
-	};
-
-	perf_counter_mmap_event(&mmap_event);
-}
-
-/*
- * IRQ throttle logging
- */
-
-static void perf_log_throttle(struct perf_counter *counter, int enable)
-{
-	struct perf_output_handle handle;
-	int ret;
-
-	struct {
-		struct perf_event_header	header;
-		u64				time;
-		u64				id;
-		u64				stream_id;
-	} throttle_event = {
-		.header = {
-			.type = PERF_EVENT_THROTTLE,
-			.misc = 0,
-			.size = sizeof(throttle_event),
-		},
-		.time		= sched_clock(),
-		.id		= primary_counter_id(counter),
-		.stream_id	= counter->id,
-	};
-
-	if (enable)
-		throttle_event.header.type = PERF_EVENT_UNTHROTTLE;
-
-	ret = perf_output_begin(&handle, counter, sizeof(throttle_event), 1, 0);
-	if (ret)
-		return;
-
-	perf_output_put(&handle, throttle_event);
-	perf_output_end(&handle);
-}
-
-/*
- * Generic counter overflow handling, sampling.
- */
-
-int perf_counter_overflow(struct perf_counter *counter, int nmi,
-			  struct perf_sample_data *data)
-{
-	int events = atomic_read(&counter->event_limit);
-	int throttle = counter->pmu->unthrottle != NULL;
-	struct hw_perf_counter *hwc = &counter->hw;
-	int ret = 0;
-
-	if (!throttle) {
-		hwc->interrupts++;
-	} else {
-		if (hwc->interrupts != MAX_INTERRUPTS) {
-			hwc->interrupts++;
-			if (HZ * hwc->interrupts >
-					(u64)sysctl_perf_counter_sample_rate) {
-				hwc->interrupts = MAX_INTERRUPTS;
-				perf_log_throttle(counter, 0);
-				ret = 1;
-			}
-		} else {
-			/*
-			 * Keep re-disabling counters even though on the previous
-			 * pass we disabled it - just in case we raced with a
-			 * sched-in and the counter got enabled again:
-			 */
-			ret = 1;
-		}
-	}
-
-	if (counter->attr.freq) {
-		u64 now = sched_clock();
-		s64 delta = now - hwc->freq_stamp;
-
-		hwc->freq_stamp = now;
-
-		if (delta > 0 && delta < TICK_NSEC)
-			perf_adjust_period(counter, NSEC_PER_SEC / (int)delta);
-	}
-
-	/*
-	 * XXX event_limit might not quite work as expected on inherited
-	 * counters
-	 */
-
-	counter->pending_kill = POLL_IN;
-	if (events && atomic_dec_and_test(&counter->event_limit)) {
-		ret = 1;
-		counter->pending_kill = POLL_HUP;
-		if (nmi) {
-			counter->pending_disable = 1;
-			perf_pending_queue(&counter->pending,
-					   perf_pending_counter);
-		} else
-			perf_counter_disable(counter);
-	}
-
-	perf_counter_output(counter, nmi, data);
-	return ret;
-}
-
-/*
- * Generic software counter infrastructure
- */
-
-/*
- * We directly increment counter->count and keep a second value in
- * counter->hw.period_left to count intervals. This period counter
- * is kept in the range [-sample_period, 0] so that we can use the
- * sign as trigger.
- */
-
-static u64 perf_swcounter_set_period(struct perf_counter *counter)
-{
-	struct hw_perf_counter *hwc = &counter->hw;
-	u64 period = hwc->last_period;
-	u64 nr, offset;
-	s64 old, val;
-
-	hwc->last_period = hwc->sample_period;
-
-again:
-	old = val = atomic64_read(&hwc->period_left);
-	if (val < 0)
-		return 0;
-
-	nr = div64_u64(period + val, period);
-	offset = nr * period;
-	val -= offset;
-	if (atomic64_cmpxchg(&hwc->period_left, old, val) != old)
-		goto again;
-
-	return nr;
-}
-
-static void perf_swcounter_overflow(struct perf_counter *counter,
-				    int nmi, struct perf_sample_data *data)
-{
-	struct hw_perf_counter *hwc = &counter->hw;
-	u64 overflow;
-
-	data->period = counter->hw.last_period;
-	overflow = perf_swcounter_set_period(counter);
-
-	if (hwc->interrupts == MAX_INTERRUPTS)
-		return;
-
-	for (; overflow; overflow--) {
-		if (perf_counter_overflow(counter, nmi, data)) {
-			/*
-			 * We inhibit the overflow from happening when
-			 * hwc->interrupts == MAX_INTERRUPTS.
-			 */
-			break;
-		}
-	}
-}
-
-static void perf_swcounter_unthrottle(struct perf_counter *counter)
-{
-	/*
-	 * Nothing to do, we already reset hwc->interrupts.
-	 */
-}
-
-static void perf_swcounter_add(struct perf_counter *counter, u64 nr,
-			       int nmi, struct perf_sample_data *data)
-{
-	struct hw_perf_counter *hwc = &counter->hw;
-
-	atomic64_add(nr, &counter->count);
-
-	if (!hwc->sample_period)
-		return;
-
-	if (!data->regs)
-		return;
-
-	if (!atomic64_add_negative(nr, &hwc->period_left))
-		perf_swcounter_overflow(counter, nmi, data);
-}
-
-static int perf_swcounter_is_counting(struct perf_counter *counter)
-{
-	/*
-	 * The counter is active, we're good!
-	 */
-	if (counter->state == PERF_COUNTER_STATE_ACTIVE)
-		return 1;
-
-	/*
-	 * The counter is off/error, not counting.
-	 */
-	if (counter->state != PERF_COUNTER_STATE_INACTIVE)
-		return 0;
-
-	/*
-	 * The counter is inactive, if the context is active
-	 * we're part of a group that didn't make it on the 'pmu',
-	 * not counting.
-	 */
-	if (counter->ctx->is_active)
-		return 0;
-
-	/*
-	 * We're inactive and the context is too, this means the
-	 * task is scheduled out, we're counting events that happen
-	 * to us, like migration events.
-	 */
-	return 1;
-}
-
-static int perf_swcounter_match(struct perf_counter *counter,
-				enum perf_type_id type,
-				u32 event, struct pt_regs *regs)
-{
-	if (!perf_swcounter_is_counting(counter))
-		return 0;
-
-	if (counter->attr.type != type)
-		return 0;
-	if (counter->attr.config != event)
-		return 0;
-
-	if (regs) {
-		if (counter->attr.exclude_user && user_mode(regs))
-			return 0;
-
-		if (counter->attr.exclude_kernel && !user_mode(regs))
-			return 0;
-	}
-
-	return 1;
-}
-
-static void perf_swcounter_ctx_event(struct perf_counter_context *ctx,
-				     enum perf_type_id type,
-				     u32 event, u64 nr, int nmi,
-				     struct perf_sample_data *data)
-{
-	struct perf_counter *counter;
-
-	if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
-		return;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(counter, &ctx->event_list, event_entry) {
-		if (perf_swcounter_match(counter, type, event, data->regs))
-			perf_swcounter_add(counter, nr, nmi, data);
-	}
-	rcu_read_unlock();
-}
-
-static int *perf_swcounter_recursion_context(struct perf_cpu_context *cpuctx)
-{
-	if (in_nmi())
-		return &cpuctx->recursion[3];
-
-	if (in_irq())
-		return &cpuctx->recursion[2];
-
-	if (in_softirq())
-		return &cpuctx->recursion[1];
-
-	return &cpuctx->recursion[0];
-}
-
-static void do_perf_swcounter_event(enum perf_type_id type, u32 event,
-				    u64 nr, int nmi,
-				    struct perf_sample_data *data)
-{
-	struct perf_cpu_context *cpuctx = &get_cpu_var(perf_cpu_context);
-	int *recursion = perf_swcounter_recursion_context(cpuctx);
-	struct perf_counter_context *ctx;
-
-	if (*recursion)
-		goto out;
-
-	(*recursion)++;
-	barrier();
-
-	perf_swcounter_ctx_event(&cpuctx->ctx, type, event,
-				 nr, nmi, data);
-	rcu_read_lock();
-	/*
-	 * doesn't really matter which of the child contexts the
-	 * events ends up in.
-	 */
-	ctx = rcu_dereference(current->perf_counter_ctxp);
-	if (ctx)
-		perf_swcounter_ctx_event(ctx, type, event, nr, nmi, data);
-	rcu_read_unlock();
-
-	barrier();
-	(*recursion)--;
-
-out:
-	put_cpu_var(perf_cpu_context);
-}
-
-void __perf_swcounter_event(u32 event, u64 nr, int nmi,
-			    struct pt_regs *regs, u64 addr)
-{
-	struct perf_sample_data data = {
-		.regs = regs,
-		.addr = addr,
-	};
-
-	do_perf_swcounter_event(PERF_TYPE_SOFTWARE, event, nr, nmi, &data);
-}
-
-static void perf_swcounter_read(struct perf_counter *counter)
-{
-}
-
-static int perf_swcounter_enable(struct perf_counter *counter)
-{
-	struct hw_perf_counter *hwc = &counter->hw;
-
-	if (hwc->sample_period) {
-		hwc->last_period = hwc->sample_period;
-		perf_swcounter_set_period(counter);
-	}
-	return 0;
-}
-
-static void perf_swcounter_disable(struct perf_counter *counter)
-{
-}
-
-static const struct pmu perf_ops_generic = {
-	.enable		= perf_swcounter_enable,
-	.disable	= perf_swcounter_disable,
-	.read		= perf_swcounter_read,
-	.unthrottle	= perf_swcounter_unthrottle,
-};
-
-/*
- * hrtimer based swcounter callback
- */
-
-static enum hrtimer_restart perf_swcounter_hrtimer(struct hrtimer *hrtimer)
-{
-	enum hrtimer_restart ret = HRTIMER_RESTART;
-	struct perf_sample_data data;
-	struct perf_counter *counter;
-	u64 period;
-
-	counter	= container_of(hrtimer, struct perf_counter, hw.hrtimer);
-	counter->pmu->read(counter);
-
-	data.addr = 0;
-	data.regs = get_irq_regs();
-	/*
-	 * In case we exclude kernel IPs or are somehow not in interrupt
-	 * context, provide the next best thing, the user IP.
-	 */
-	if ((counter->attr.exclude_kernel || !data.regs) &&
-			!counter->attr.exclude_user)
-		data.regs = task_pt_regs(current);
-
-	if (data.regs) {
-		if (perf_counter_overflow(counter, 0, &data))
-			ret = HRTIMER_NORESTART;
-	}
-
-	period = max_t(u64, 10000, counter->hw.sample_period);
-	hrtimer_forward_now(hrtimer, ns_to_ktime(period));
-
-	return ret;
-}
-
-/*
- * Software counter: cpu wall time clock
- */
-
-static void cpu_clock_perf_counter_update(struct perf_counter *counter)
-{
-	int cpu = raw_smp_processor_id();
-	s64 prev;
-	u64 now;
-
-	now = cpu_clock(cpu);
-	prev = atomic64_read(&counter->hw.prev_count);
-	atomic64_set(&counter->hw.prev_count, now);
-	atomic64_add(now - prev, &counter->count);
-}
-
-static int cpu_clock_perf_counter_enable(struct perf_counter *counter)
-{
-	struct hw_perf_counter *hwc = &counter->hw;
-	int cpu = raw_smp_processor_id();
-
-	atomic64_set(&hwc->prev_count, cpu_clock(cpu));
-	hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-	hwc->hrtimer.function = perf_swcounter_hrtimer;
-	if (hwc->sample_period) {
-		u64 period = max_t(u64, 10000, hwc->sample_period);
-		__hrtimer_start_range_ns(&hwc->hrtimer,
-				ns_to_ktime(period), 0,
-				HRTIMER_MODE_REL, 0);
-	}
-
-	return 0;
-}
-
-static void cpu_clock_perf_counter_disable(struct perf_counter *counter)
-{
-	if (counter->hw.sample_period)
-		hrtimer_cancel(&counter->hw.hrtimer);
-	cpu_clock_perf_counter_update(counter);
-}
-
-static void cpu_clock_perf_counter_read(struct perf_counter *counter)
-{
-	cpu_clock_perf_counter_update(counter);
-}
-
-static const struct pmu perf_ops_cpu_clock = {
-	.enable		= cpu_clock_perf_counter_enable,
-	.disable	= cpu_clock_perf_counter_disable,
-	.read		= cpu_clock_perf_counter_read,
-};
-
-/*
- * Software counter: task time clock
- */
-
-static void task_clock_perf_counter_update(struct perf_counter *counter, u64 now)
-{
-	u64 prev;
-	s64 delta;
-
-	prev = atomic64_xchg(&counter->hw.prev_count, now);
-	delta = now - prev;
-	atomic64_add(delta, &counter->count);
-}
-
-static int task_clock_perf_counter_enable(struct perf_counter *counter)
-{
-	struct hw_perf_counter *hwc = &counter->hw;
-	u64 now;
-
-	now = counter->ctx->time;
-
-	atomic64_set(&hwc->prev_count, now);
-	hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-	hwc->hrtimer.function = perf_swcounter_hrtimer;
-	if (hwc->sample_period) {
-		u64 period = max_t(u64, 10000, hwc->sample_period);
-		__hrtimer_start_range_ns(&hwc->hrtimer,
-				ns_to_ktime(period), 0,
-				HRTIMER_MODE_REL, 0);
-	}
-
-	return 0;
-}
-
-static void task_clock_perf_counter_disable(struct perf_counter *counter)
-{
-	if (counter->hw.sample_period)
-		hrtimer_cancel(&counter->hw.hrtimer);
-	task_clock_perf_counter_update(counter, counter->ctx->time);
-
-}
-
-static void task_clock_perf_counter_read(struct perf_counter *counter)
-{
-	u64 time;
-
-	if (!in_nmi()) {
-		update_context_time(counter->ctx);
-		time = counter->ctx->time;
-	} else {
-		u64 now = perf_clock();
-		u64 delta = now - counter->ctx->timestamp;
-		time = counter->ctx->time + delta;
-	}
-
-	task_clock_perf_counter_update(counter, time);
-}
-
-static const struct pmu perf_ops_task_clock = {
-	.enable		= task_clock_perf_counter_enable,
-	.disable	= task_clock_perf_counter_disable,
-	.read		= task_clock_perf_counter_read,
-};
-
-#ifdef CONFIG_EVENT_PROFILE
-void perf_tpcounter_event(int event_id, u64 addr, u64 count, void *record,
-			  int entry_size)
-{
-	struct perf_raw_record raw = {
-		.size = entry_size,
-		.data = record,
-	};
-
-	struct perf_sample_data data = {
-		.regs = get_irq_regs(),
-		.addr = addr,
-		.raw = &raw,
-	};
-
-	if (!data.regs)
-		data.regs = task_pt_regs(current);
-
-	do_perf_swcounter_event(PERF_TYPE_TRACEPOINT, event_id, count, 1, &data);
-}
-EXPORT_SYMBOL_GPL(perf_tpcounter_event);
-
-extern int ftrace_profile_enable(int);
-extern void ftrace_profile_disable(int);
-
-static void tp_perf_counter_destroy(struct perf_counter *counter)
-{
-	ftrace_profile_disable(counter->attr.config);
-}
-
-static const struct pmu *tp_perf_counter_init(struct perf_counter *counter)
-{
-	/*
-	 * Raw tracepoint data is a severe data leak, only allow root to
-	 * have these.
-	 */
-	if ((counter->attr.sample_type & PERF_SAMPLE_RAW) &&
-			!capable(CAP_SYS_ADMIN))
-		return ERR_PTR(-EPERM);
-
-	if (ftrace_profile_enable(counter->attr.config))
-		return NULL;
-
-	counter->destroy = tp_perf_counter_destroy;
-
-	return &perf_ops_generic;
-}
-#else
-static const struct pmu *tp_perf_counter_init(struct perf_counter *counter)
-{
-	return NULL;
-}
-#endif
-
-atomic_t perf_swcounter_enabled[PERF_COUNT_SW_MAX];
-
-static void sw_perf_counter_destroy(struct perf_counter *counter)
-{
-	u64 event = counter->attr.config;
-
-	WARN_ON(counter->parent);
-
-	atomic_dec(&perf_swcounter_enabled[event]);
-}
-
-static const struct pmu *sw_perf_counter_init(struct perf_counter *counter)
-{
-	const struct pmu *pmu = NULL;
-	u64 event = counter->attr.config;
-
-	/*
-	 * Software counters (currently) can't in general distinguish
-	 * between user, kernel and hypervisor events.
-	 * However, context switches and cpu migrations are considered
-	 * to be kernel events, and page faults are never hypervisor
-	 * events.
-	 */
-	switch (event) {
-	case PERF_COUNT_SW_CPU_CLOCK:
-		pmu = &perf_ops_cpu_clock;
-
-		break;
-	case PERF_COUNT_SW_TASK_CLOCK:
-		/*
-		 * If the user instantiates this as a per-cpu counter,
-		 * use the cpu_clock counter instead.
-		 */
-		if (counter->ctx->task)
-			pmu = &perf_ops_task_clock;
-		else
-			pmu = &perf_ops_cpu_clock;
-
-		break;
-	case PERF_COUNT_SW_PAGE_FAULTS:
-	case PERF_COUNT_SW_PAGE_FAULTS_MIN:
-	case PERF_COUNT_SW_PAGE_FAULTS_MAJ:
-	case PERF_COUNT_SW_CONTEXT_SWITCHES:
-	case PERF_COUNT_SW_CPU_MIGRATIONS:
-		if (!counter->parent) {
-			atomic_inc(&perf_swcounter_enabled[event]);
-			counter->destroy = sw_perf_counter_destroy;
-		}
-		pmu = &perf_ops_generic;
-		break;
-	}
-
-	return pmu;
-}
-
-/*
- * Allocate and initialize a counter structure
- */
-static struct perf_counter *
-perf_counter_alloc(struct perf_counter_attr *attr,
-		   int cpu,
-		   struct perf_counter_context *ctx,
-		   struct perf_counter *group_leader,
-		   struct perf_counter *parent_counter,
-		   gfp_t gfpflags)
-{
-	const struct pmu *pmu;
-	struct perf_counter *counter;
-	struct hw_perf_counter *hwc;
-	long err;
-
-	counter = kzalloc(sizeof(*counter), gfpflags);
-	if (!counter)
-		return ERR_PTR(-ENOMEM);
-
-	/*
-	 * Single counters are their own group leaders, with an
-	 * empty sibling list:
-	 */
-	if (!group_leader)
-		group_leader = counter;
-
-	mutex_init(&counter->child_mutex);
-	INIT_LIST_HEAD(&counter->child_list);
-
-	INIT_LIST_HEAD(&counter->list_entry);
-	INIT_LIST_HEAD(&counter->event_entry);
-	INIT_LIST_HEAD(&counter->sibling_list);
-	init_waitqueue_head(&counter->waitq);
-
-	mutex_init(&counter->mmap_mutex);
-
-	counter->cpu		= cpu;
-	counter->attr		= *attr;
-	counter->group_leader	= group_leader;
-	counter->pmu		= NULL;
-	counter->ctx		= ctx;
-	counter->oncpu		= -1;
-
-	counter->parent		= parent_counter;
-
-	counter->ns		= get_pid_ns(current->nsproxy->pid_ns);
-	counter->id		= atomic64_inc_return(&perf_counter_id);
-
-	counter->state		= PERF_COUNTER_STATE_INACTIVE;
-
-	if (attr->disabled)
-		counter->state = PERF_COUNTER_STATE_OFF;
-
-	pmu = NULL;
-
-	hwc = &counter->hw;
-	hwc->sample_period = attr->sample_period;
-	if (attr->freq && attr->sample_freq)
-		hwc->sample_period = 1;
-	hwc->last_period = hwc->sample_period;
-
-	atomic64_set(&hwc->period_left, hwc->sample_period);
-
-	/*
-	 * we currently do not support PERF_FORMAT_GROUP on inherited counters
-	 */
-	if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP))
-		goto done;
-
-	switch (attr->type) {
-	case PERF_TYPE_RAW:
-	case PERF_TYPE_HARDWARE:
-	case PERF_TYPE_HW_CACHE:
-		pmu = hw_perf_counter_init(counter);
-		break;
-
-	case PERF_TYPE_SOFTWARE:
-		pmu = sw_perf_counter_init(counter);
-		break;
-
-	case PERF_TYPE_TRACEPOINT:
-		pmu = tp_perf_counter_init(counter);
-		break;
-
-	default:
-		break;
-	}
-done:
-	err = 0;
-	if (!pmu)
-		err = -EINVAL;
-	else if (IS_ERR(pmu))
-		err = PTR_ERR(pmu);
-
-	if (err) {
-		if (counter->ns)
-			put_pid_ns(counter->ns);
-		kfree(counter);
-		return ERR_PTR(err);
-	}
-
-	counter->pmu = pmu;
-
-	if (!counter->parent) {
-		atomic_inc(&nr_counters);
-		if (counter->attr.mmap)
-			atomic_inc(&nr_mmap_counters);
-		if (counter->attr.comm)
-			atomic_inc(&nr_comm_counters);
-		if (counter->attr.task)
-			atomic_inc(&nr_task_counters);
-	}
-
-	return counter;
-}
-
-static int perf_copy_attr(struct perf_counter_attr __user *uattr,
-			  struct perf_counter_attr *attr)
-{
-	int ret;
-	u32 size;
-
-	if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0))
-		return -EFAULT;
-
-	/*
-	 * zero the full structure, so that a short copy will be nice.
-	 */
-	memset(attr, 0, sizeof(*attr));
-
-	ret = get_user(size, &uattr->size);
-	if (ret)
-		return ret;
-
-	if (size > PAGE_SIZE)	/* silly large */
-		goto err_size;
-
-	if (!size)		/* abi compat */
-		size = PERF_ATTR_SIZE_VER0;
-
-	if (size < PERF_ATTR_SIZE_VER0)
-		goto err_size;
-
-	/*
-	 * If we're handed a bigger struct than we know of,
-	 * ensure all the unknown bits are 0.
-	 */
-	if (size > sizeof(*attr)) {
-		unsigned long val;
-		unsigned long __user *addr;
-		unsigned long __user *end;
-
-		addr = PTR_ALIGN((void __user *)uattr + sizeof(*attr),
-				sizeof(unsigned long));
-		end  = PTR_ALIGN((void __user *)uattr + size,
-				sizeof(unsigned long));
-
-		for (; addr < end; addr += sizeof(unsigned long)) {
-			ret = get_user(val, addr);
-			if (ret)
-				return ret;
-			if (val)
-				goto err_size;
-		}
-	}
-
-	ret = copy_from_user(attr, uattr, size);
-	if (ret)
-		return -EFAULT;
-
-	/*
-	 * If the type exists, the corresponding creation will verify
-	 * the attr->config.
-	 */
-	if (attr->type >= PERF_TYPE_MAX)
-		return -EINVAL;
-
-	if (attr->__reserved_1 || attr->__reserved_2 || attr->__reserved_3)
-		return -EINVAL;
-
-	if (attr->sample_type & ~(PERF_SAMPLE_MAX-1))
-		return -EINVAL;
-
-	if (attr->read_format & ~(PERF_FORMAT_MAX-1))
-		return -EINVAL;
-
-out:
-	return ret;
-
-err_size:
-	put_user(sizeof(*attr), &uattr->size);
-	ret = -E2BIG;
-	goto out;
-}
-
-/**
- * sys_perf_counter_open - open a performance counter, associate it to a task/cpu
- *
- * @attr_uptr:	event type attributes for monitoring/sampling
- * @pid:		target pid
- * @cpu:		target cpu
- * @group_fd:		group leader counter fd
- */
-SYSCALL_DEFINE5(perf_counter_open,
-		struct perf_counter_attr __user *, attr_uptr,
-		pid_t, pid, int, cpu, int, group_fd, unsigned long, flags)
-{
-	struct perf_counter *counter, *group_leader;
-	struct perf_counter_attr attr;
-	struct perf_counter_context *ctx;
-	struct file *counter_file = NULL;
-	struct file *group_file = NULL;
-	int fput_needed = 0;
-	int fput_needed2 = 0;
-	int ret;
-
-	/* for future expandability... */
-	if (flags)
-		return -EINVAL;
-
-	ret = perf_copy_attr(attr_uptr, &attr);
-	if (ret)
-		return ret;
-
-	if (!attr.exclude_kernel) {
-		if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN))
-			return -EACCES;
-	}
-
-	if (attr.freq) {
-		if (attr.sample_freq > sysctl_perf_counter_sample_rate)
-			return -EINVAL;
-	}
-
-	/*
-	 * Get the target context (task or percpu):
-	 */
-	ctx = find_get_context(pid, cpu);
-	if (IS_ERR(ctx))
-		return PTR_ERR(ctx);
-
-	/*
-	 * Look up the group leader (we will attach this counter to it):
-	 */
-	group_leader = NULL;
-	if (group_fd != -1) {
-		ret = -EINVAL;
-		group_file = fget_light(group_fd, &fput_needed);
-		if (!group_file)
-			goto err_put_context;
-		if (group_file->f_op != &perf_fops)
-			goto err_put_context;
-
-		group_leader = group_file->private_data;
-		/*
-		 * Do not allow a recursive hierarchy (this new sibling
-		 * becoming part of another group-sibling):
-		 */
-		if (group_leader->group_leader != group_leader)
-			goto err_put_context;
-		/*
-		 * Do not allow to attach to a group in a different
-		 * task or CPU context:
-		 */
-		if (group_leader->ctx != ctx)
-			goto err_put_context;
-		/*
-		 * Only a group leader can be exclusive or pinned
-		 */
-		if (attr.exclusive || attr.pinned)
-			goto err_put_context;
-	}
-
-	counter = perf_counter_alloc(&attr, cpu, ctx, group_leader,
-				     NULL, GFP_KERNEL);
-	ret = PTR_ERR(counter);
-	if (IS_ERR(counter))
-		goto err_put_context;
-
-	ret = anon_inode_getfd("[perf_counter]", &perf_fops, counter, 0);
-	if (ret < 0)
-		goto err_free_put_context;
-
-	counter_file = fget_light(ret, &fput_needed2);
-	if (!counter_file)
-		goto err_free_put_context;
-
-	counter->filp = counter_file;
-	WARN_ON_ONCE(ctx->parent_ctx);
-	mutex_lock(&ctx->mutex);
-	perf_install_in_context(ctx, counter, cpu);
-	++ctx->generation;
-	mutex_unlock(&ctx->mutex);
-
-	counter->owner = current;
-	get_task_struct(current);
-	mutex_lock(&current->perf_counter_mutex);
-	list_add_tail(&counter->owner_entry, &current->perf_counter_list);
-	mutex_unlock(&current->perf_counter_mutex);
-
-	fput_light(counter_file, fput_needed2);
-
-out_fput:
-	fput_light(group_file, fput_needed);
-
-	return ret;
-
-err_free_put_context:
-	kfree(counter);
-
-err_put_context:
-	put_ctx(ctx);
-
-	goto out_fput;
-}
-
-/*
- * inherit a counter from parent task to child task:
- */
-static struct perf_counter *
-inherit_counter(struct perf_counter *parent_counter,
-	      struct task_struct *parent,
-	      struct perf_counter_context *parent_ctx,
-	      struct task_struct *child,
-	      struct perf_counter *group_leader,
-	      struct perf_counter_context *child_ctx)
-{
-	struct perf_counter *child_counter;
-
-	/*
-	 * Instead of creating recursive hierarchies of counters,
-	 * we link inherited counters back to the original parent,
-	 * which has a filp for sure, which we use as the reference
-	 * count:
-	 */
-	if (parent_counter->parent)
-		parent_counter = parent_counter->parent;
-
-	child_counter = perf_counter_alloc(&parent_counter->attr,
-					   parent_counter->cpu, child_ctx,
-					   group_leader, parent_counter,
-					   GFP_KERNEL);
-	if (IS_ERR(child_counter))
-		return child_counter;
-	get_ctx(child_ctx);
-
-	/*
-	 * Make the child state follow the state of the parent counter,
-	 * not its attr.disabled bit.  We hold the parent's mutex,
-	 * so we won't race with perf_counter_{en, dis}able_family.
-	 */
-	if (parent_counter->state >= PERF_COUNTER_STATE_INACTIVE)
-		child_counter->state = PERF_COUNTER_STATE_INACTIVE;
-	else
-		child_counter->state = PERF_COUNTER_STATE_OFF;
-
-	if (parent_counter->attr.freq)
-		child_counter->hw.sample_period = parent_counter->hw.sample_period;
-
-	/*
-	 * Link it up in the child's context:
-	 */
-	add_counter_to_ctx(child_counter, child_ctx);
-
-	/*
-	 * Get a reference to the parent filp - we will fput it
-	 * when the child counter exits. This is safe to do because
-	 * we are in the parent and we know that the filp still
-	 * exists and has a nonzero count:
-	 */
-	atomic_long_inc(&parent_counter->filp->f_count);
-
-	/*
-	 * Link this into the parent counter's child list
-	 */
-	WARN_ON_ONCE(parent_counter->ctx->parent_ctx);
-	mutex_lock(&parent_counter->child_mutex);
-	list_add_tail(&child_counter->child_list, &parent_counter->child_list);
-	mutex_unlock(&parent_counter->child_mutex);
-
-	return child_counter;
-}
-
-static int inherit_group(struct perf_counter *parent_counter,
-	      struct task_struct *parent,
-	      struct perf_counter_context *parent_ctx,
-	      struct task_struct *child,
-	      struct perf_counter_context *child_ctx)
-{
-	struct perf_counter *leader;
-	struct perf_counter *sub;
-	struct perf_counter *child_ctr;
-
-	leader = inherit_counter(parent_counter, parent, parent_ctx,
-				 child, NULL, child_ctx);
-	if (IS_ERR(leader))
-		return PTR_ERR(leader);
-	list_for_each_entry(sub, &parent_counter->sibling_list, list_entry) {
-		child_ctr = inherit_counter(sub, parent, parent_ctx,
-					    child, leader, child_ctx);
-		if (IS_ERR(child_ctr))
-			return PTR_ERR(child_ctr);
-	}
-	return 0;
-}
-
-static void sync_child_counter(struct perf_counter *child_counter,
-			       struct task_struct *child)
-{
-	struct perf_counter *parent_counter = child_counter->parent;
-	u64 child_val;
-
-	if (child_counter->attr.inherit_stat)
-		perf_counter_read_event(child_counter, child);
-
-	child_val = atomic64_read(&child_counter->count);
-
-	/*
-	 * Add back the child's count to the parent's count:
-	 */
-	atomic64_add(child_val, &parent_counter->count);
-	atomic64_add(child_counter->total_time_enabled,
-		     &parent_counter->child_total_time_enabled);
-	atomic64_add(child_counter->total_time_running,
-		     &parent_counter->child_total_time_running);
-
-	/*
-	 * Remove this counter from the parent's list
-	 */
-	WARN_ON_ONCE(parent_counter->ctx->parent_ctx);
-	mutex_lock(&parent_counter->child_mutex);
-	list_del_init(&child_counter->child_list);
-	mutex_unlock(&parent_counter->child_mutex);
-
-	/*
-	 * Release the parent counter, if this was the last
-	 * reference to it.
-	 */
-	fput(parent_counter->filp);
-}
-
-static void
-__perf_counter_exit_task(struct perf_counter *child_counter,
-			 struct perf_counter_context *child_ctx,
-			 struct task_struct *child)
-{
-	struct perf_counter *parent_counter;
-
-	update_counter_times(child_counter);
-	perf_counter_remove_from_context(child_counter);
-
-	parent_counter = child_counter->parent;
-	/*
-	 * It can happen that parent exits first, and has counters
-	 * that are still around due to the child reference. These
-	 * counters need to be zapped - but otherwise linger.
-	 */
-	if (parent_counter) {
-		sync_child_counter(child_counter, child);
-		free_counter(child_counter);
-	}
-}
-
-/*
- * When a child task exits, feed back counter values to parent counters.
- */
-void perf_counter_exit_task(struct task_struct *child)
-{
-	struct perf_counter *child_counter, *tmp;
-	struct perf_counter_context *child_ctx;
-	unsigned long flags;
-
-	if (likely(!child->perf_counter_ctxp)) {
-		perf_counter_task(child, NULL, 0);
-		return;
-	}
-
-	local_irq_save(flags);
-	/*
-	 * We can't reschedule here because interrupts are disabled,
-	 * and either child is current or it is a task that can't be
-	 * scheduled, so we are now safe from rescheduling changing
-	 * our context.
-	 */
-	child_ctx = child->perf_counter_ctxp;
-	__perf_counter_task_sched_out(child_ctx);
-
-	/*
-	 * Take the context lock here so that if find_get_context is
-	 * reading child->perf_counter_ctxp, we wait until it has
-	 * incremented the context's refcount before we do put_ctx below.
-	 */
-	spin_lock(&child_ctx->lock);
-	child->perf_counter_ctxp = NULL;
-	/*
-	 * If this context is a clone; unclone it so it can't get
-	 * swapped to another process while we're removing all
-	 * the counters from it.
-	 */
-	unclone_ctx(child_ctx);
-	spin_unlock_irqrestore(&child_ctx->lock, flags);
-
-	/*
-	 * Report the task dead after unscheduling the counters so that we
-	 * won't get any samples after PERF_EVENT_EXIT. We can however still
-	 * get a few PERF_EVENT_READ events.
-	 */
-	perf_counter_task(child, child_ctx, 0);
-
-	/*
-	 * We can recurse on the same lock type through:
-	 *
-	 *   __perf_counter_exit_task()
-	 *     sync_child_counter()
-	 *       fput(parent_counter->filp)
-	 *         perf_release()
-	 *           mutex_lock(&ctx->mutex)
-	 *
-	 * But since its the parent context it won't be the same instance.
-	 */
-	mutex_lock_nested(&child_ctx->mutex, SINGLE_DEPTH_NESTING);
-
-again:
-	list_for_each_entry_safe(child_counter, tmp, &child_ctx->counter_list,
-				 list_entry)
-		__perf_counter_exit_task(child_counter, child_ctx, child);
-
-	/*
-	 * If the last counter was a group counter, it will have appended all
-	 * its siblings to the list, but we obtained 'tmp' before that which
-	 * will still point to the list head terminating the iteration.
-	 */
-	if (!list_empty(&child_ctx->counter_list))
-		goto again;
-
-	mutex_unlock(&child_ctx->mutex);
-
-	put_ctx(child_ctx);
-}
-
-/*
- * free an unexposed, unused context as created by inheritance by
- * init_task below, used by fork() in case of fail.
- */
-void perf_counter_free_task(struct task_struct *task)
-{
-	struct perf_counter_context *ctx = task->perf_counter_ctxp;
-	struct perf_counter *counter, *tmp;
-
-	if (!ctx)
-		return;
-
-	mutex_lock(&ctx->mutex);
-again:
-	list_for_each_entry_safe(counter, tmp, &ctx->counter_list, list_entry) {
-		struct perf_counter *parent = counter->parent;
-
-		if (WARN_ON_ONCE(!parent))
-			continue;
-
-		mutex_lock(&parent->child_mutex);
-		list_del_init(&counter->child_list);
-		mutex_unlock(&parent->child_mutex);
-
-		fput(parent->filp);
-
-		list_del_counter(counter, ctx);
-		free_counter(counter);
-	}
-
-	if (!list_empty(&ctx->counter_list))
-		goto again;
-
-	mutex_unlock(&ctx->mutex);
-
-	put_ctx(ctx);
-}
-
-/*
- * Initialize the perf_counter context in task_struct
- */
-int perf_counter_init_task(struct task_struct *child)
-{
-	struct perf_counter_context *child_ctx, *parent_ctx;
-	struct perf_counter_context *cloned_ctx;
-	struct perf_counter *counter;
-	struct task_struct *parent = current;
-	int inherited_all = 1;
-	int ret = 0;
-
-	child->perf_counter_ctxp = NULL;
-
-	mutex_init(&child->perf_counter_mutex);
-	INIT_LIST_HEAD(&child->perf_counter_list);
-
-	if (likely(!parent->perf_counter_ctxp))
-		return 0;
-
-	/*
-	 * This is executed from the parent task context, so inherit
-	 * counters that have been marked for cloning.
-	 * First allocate and initialize a context for the child.
-	 */
-
-	child_ctx = kmalloc(sizeof(struct perf_counter_context), GFP_KERNEL);
-	if (!child_ctx)
-		return -ENOMEM;
-
-	__perf_counter_init_context(child_ctx, child);
-	child->perf_counter_ctxp = child_ctx;
-	get_task_struct(child);
-
-	/*
-	 * If the parent's context is a clone, pin it so it won't get
-	 * swapped under us.
-	 */
-	parent_ctx = perf_pin_task_context(parent);
-
-	/*
-	 * No need to check if parent_ctx != NULL here; since we saw
-	 * it non-NULL earlier, the only reason for it to become NULL
-	 * is if we exit, and since we're currently in the middle of
-	 * a fork we can't be exiting at the same time.
-	 */
-
-	/*
-	 * Lock the parent list. No need to lock the child - not PID
-	 * hashed yet and not running, so nobody can access it.
-	 */
-	mutex_lock(&parent_ctx->mutex);
-
-	/*
-	 * We dont have to disable NMIs - we are only looking at
-	 * the list, not manipulating it:
-	 */
-	list_for_each_entry_rcu(counter, &parent_ctx->event_list, event_entry) {
-		if (counter != counter->group_leader)
-			continue;
-
-		if (!counter->attr.inherit) {
-			inherited_all = 0;
-			continue;
-		}
-
-		ret = inherit_group(counter, parent, parent_ctx,
-					     child, child_ctx);
-		if (ret) {
-			inherited_all = 0;
-			break;
-		}
-	}
-
-	if (inherited_all) {
-		/*
-		 * Mark the child context as a clone of the parent
-		 * context, or of whatever the parent is a clone of.
-		 * Note that if the parent is a clone, it could get
-		 * uncloned at any point, but that doesn't matter
-		 * because the list of counters and the generation
-		 * count can't have changed since we took the mutex.
-		 */
-		cloned_ctx = rcu_dereference(parent_ctx->parent_ctx);
-		if (cloned_ctx) {
-			child_ctx->parent_ctx = cloned_ctx;
-			child_ctx->parent_gen = parent_ctx->parent_gen;
-		} else {
-			child_ctx->parent_ctx = parent_ctx;
-			child_ctx->parent_gen = parent_ctx->generation;
-		}
-		get_ctx(child_ctx->parent_ctx);
-	}
-
-	mutex_unlock(&parent_ctx->mutex);
-
-	perf_unpin_context(parent_ctx);
-
-	return ret;
-}
-
-static void __cpuinit perf_counter_init_cpu(int cpu)
-{
-	struct perf_cpu_context *cpuctx;
-
-	cpuctx = &per_cpu(perf_cpu_context, cpu);
-	__perf_counter_init_context(&cpuctx->ctx, NULL);
-
-	spin_lock(&perf_resource_lock);
-	cpuctx->max_pertask = perf_max_counters - perf_reserved_percpu;
-	spin_unlock(&perf_resource_lock);
-
-	hw_perf_counter_setup(cpu);
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-static void __perf_counter_exit_cpu(void *info)
-{
-	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
-	struct perf_counter_context *ctx = &cpuctx->ctx;
-	struct perf_counter *counter, *tmp;
-
-	list_for_each_entry_safe(counter, tmp, &ctx->counter_list, list_entry)
-		__perf_counter_remove_from_context(counter);
-}
-static void perf_counter_exit_cpu(int cpu)
-{
-	struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
-	struct perf_counter_context *ctx = &cpuctx->ctx;
-
-	mutex_lock(&ctx->mutex);
-	smp_call_function_single(cpu, __perf_counter_exit_cpu, NULL, 1);
-	mutex_unlock(&ctx->mutex);
-}
-#else
-static inline void perf_counter_exit_cpu(int cpu) { }
-#endif
-
-static int __cpuinit
-perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu)
-{
-	unsigned int cpu = (long)hcpu;
-
-	switch (action) {
-
-	case CPU_UP_PREPARE:
-	case CPU_UP_PREPARE_FROZEN:
-		perf_counter_init_cpu(cpu);
-		break;
-
-	case CPU_ONLINE:
-	case CPU_ONLINE_FROZEN:
-		hw_perf_counter_setup_online(cpu);
-		break;
-
-	case CPU_DOWN_PREPARE:
-	case CPU_DOWN_PREPARE_FROZEN:
-		perf_counter_exit_cpu(cpu);
-		break;
-
-	default:
-		break;
-	}
-
-	return NOTIFY_OK;
-}
-
-/*
- * This has to have a higher priority than migration_notifier in sched.c.
- */
-static struct notifier_block __cpuinitdata perf_cpu_nb = {
-	.notifier_call		= perf_cpu_notify,
-	.priority		= 20,
-};
-
-void __init perf_counter_init(void)
-{
-	perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_UP_PREPARE,
-			(void *)(long)smp_processor_id());
-	perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_ONLINE,
-			(void *)(long)smp_processor_id());
-	register_cpu_notifier(&perf_cpu_nb);
-}
-
-static ssize_t perf_show_reserve_percpu(struct sysdev_class *class, char *buf)
-{
-	return sprintf(buf, "%d\n", perf_reserved_percpu);
-}
-
-static ssize_t
-perf_set_reserve_percpu(struct sysdev_class *class,
-			const char *buf,
-			size_t count)
-{
-	struct perf_cpu_context *cpuctx;
-	unsigned long val;
-	int err, cpu, mpt;
-
-	err = strict_strtoul(buf, 10, &val);
-	if (err)
-		return err;
-	if (val > perf_max_counters)
-		return -EINVAL;
-
-	spin_lock(&perf_resource_lock);
-	perf_reserved_percpu = val;
-	for_each_online_cpu(cpu) {
-		cpuctx = &per_cpu(perf_cpu_context, cpu);
-		spin_lock_irq(&cpuctx->ctx.lock);
-		mpt = min(perf_max_counters - cpuctx->ctx.nr_counters,
-			  perf_max_counters - perf_reserved_percpu);
-		cpuctx->max_pertask = mpt;
-		spin_unlock_irq(&cpuctx->ctx.lock);
-	}
-	spin_unlock(&perf_resource_lock);
-
-	return count;
-}
-
-static ssize_t perf_show_overcommit(struct sysdev_class *class, char *buf)
-{
-	return sprintf(buf, "%d\n", perf_overcommit);
-}
-
-static ssize_t
-perf_set_overcommit(struct sysdev_class *class, const char *buf, size_t count)
-{
-	unsigned long val;
-	int err;
-
-	err = strict_strtoul(buf, 10, &val);
-	if (err)
-		return err;
-	if (val > 1)
-		return -EINVAL;
-
-	spin_lock(&perf_resource_lock);
-	perf_overcommit = val;
-	spin_unlock(&perf_resource_lock);
-
-	return count;
-}
-
-static SYSDEV_CLASS_ATTR(
-				reserve_percpu,
-				0644,
-				perf_show_reserve_percpu,
-				perf_set_reserve_percpu
-			);
-
-static SYSDEV_CLASS_ATTR(
-				overcommit,
-				0644,
-				perf_show_overcommit,
-				perf_set_overcommit
-			);
-
-static struct attribute *perfclass_attrs[] = {
-	&attr_reserve_percpu.attr,
-	&attr_overcommit.attr,
-	NULL
-};
-
-static struct attribute_group perfclass_attr_group = {
-	.attrs			= perfclass_attrs,
-	.name			= "perf_counters",
-};
-
-static int __init perf_counter_sysfs_init(void)
-{
-	return sysfs_create_group(&cpu_sysdev_class.kset.kobj,
-				  &perfclass_attr_group);
-}
-device_initcall(perf_counter_sysfs_init);
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
new file mode 100644
index 0000000..76ac4db
--- /dev/null
+++ b/kernel/perf_event.c
@@ -0,0 +1,5000 @@
+/*
+ * Performance events core code:
+ *
+ *  Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
+ *  Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar
+ *  Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ *  Copyright  ©  2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
+ *
+ * For licensing details see kernel-base/COPYING
+ */
+
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/cpu.h>
+#include <linux/smp.h>
+#include <linux/file.h>
+#include <linux/poll.h>
+#include <linux/sysfs.h>
+#include <linux/dcache.h>
+#include <linux/percpu.h>
+#include <linux/ptrace.h>
+#include <linux/vmstat.h>
+#include <linux/hardirq.h>
+#include <linux/rculist.h>
+#include <linux/uaccess.h>
+#include <linux/syscalls.h>
+#include <linux/anon_inodes.h>
+#include <linux/kernel_stat.h>
+#include <linux/perf_event.h>
+
+#include <asm/irq_regs.h>
+
+/*
+ * Each CPU has a list of per CPU events:
+ */
+DEFINE_PER_CPU(struct perf_cpu_context, perf_cpu_context);
+
+int perf_max_events __read_mostly = 1;
+static int perf_reserved_percpu __read_mostly;
+static int perf_overcommit __read_mostly = 1;
+
+static atomic_t nr_events __read_mostly;
+static atomic_t nr_mmap_events __read_mostly;
+static atomic_t nr_comm_events __read_mostly;
+static atomic_t nr_task_events __read_mostly;
+
+/*
+ * perf event paranoia level:
+ *  -1 - not paranoid at all
+ *   0 - disallow raw tracepoint access for unpriv
+ *   1 - disallow cpu events for unpriv
+ *   2 - disallow kernel profiling for unpriv
+ */
+int sysctl_perf_event_paranoid __read_mostly = 1;
+
+static inline bool perf_paranoid_tracepoint_raw(void)
+{
+	return sysctl_perf_event_paranoid > -1;
+}
+
+static inline bool perf_paranoid_cpu(void)
+{
+	return sysctl_perf_event_paranoid > 0;
+}
+
+static inline bool perf_paranoid_kernel(void)
+{
+	return sysctl_perf_event_paranoid > 1;
+}
+
+int sysctl_perf_event_mlock __read_mostly = 512; /* 'free' kb per user */
+
+/*
+ * max perf event sample rate
+ */
+int sysctl_perf_event_sample_rate __read_mostly = 100000;
+
+static atomic64_t perf_event_id;
+
+/*
+ * Lock for (sysadmin-configurable) event reservations:
+ */
+static DEFINE_SPINLOCK(perf_resource_lock);
+
+/*
+ * Architecture provided APIs - weak aliases:
+ */
+extern __weak const struct pmu *hw_perf_event_init(struct perf_event *event)
+{
+	return NULL;
+}
+
+void __weak hw_perf_disable(void)		{ barrier(); }
+void __weak hw_perf_enable(void)		{ barrier(); }
+
+void __weak hw_perf_event_setup(int cpu)	{ barrier(); }
+void __weak hw_perf_event_setup_online(int cpu)	{ barrier(); }
+
+int __weak
+hw_perf_group_sched_in(struct perf_event *group_leader,
+	       struct perf_cpu_context *cpuctx,
+	       struct perf_event_context *ctx, int cpu)
+{
+	return 0;
+}
+
+void __weak perf_event_print_debug(void)	{ }
+
+static DEFINE_PER_CPU(int, perf_disable_count);
+
+void __perf_disable(void)
+{
+	__get_cpu_var(perf_disable_count)++;
+}
+
+bool __perf_enable(void)
+{
+	return !--__get_cpu_var(perf_disable_count);
+}
+
+void perf_disable(void)
+{
+	__perf_disable();
+	hw_perf_disable();
+}
+
+void perf_enable(void)
+{
+	if (__perf_enable())
+		hw_perf_enable();
+}
+
+static void get_ctx(struct perf_event_context *ctx)
+{
+	WARN_ON(!atomic_inc_not_zero(&ctx->refcount));
+}
+
+static void free_ctx(struct rcu_head *head)
+{
+	struct perf_event_context *ctx;
+
+	ctx = container_of(head, struct perf_event_context, rcu_head);
+	kfree(ctx);
+}
+
+static void put_ctx(struct perf_event_context *ctx)
+{
+	if (atomic_dec_and_test(&ctx->refcount)) {
+		if (ctx->parent_ctx)
+			put_ctx(ctx->parent_ctx);
+		if (ctx->task)
+			put_task_struct(ctx->task);
+		call_rcu(&ctx->rcu_head, free_ctx);
+	}
+}
+
+static void unclone_ctx(struct perf_event_context *ctx)
+{
+	if (ctx->parent_ctx) {
+		put_ctx(ctx->parent_ctx);
+		ctx->parent_ctx = NULL;
+	}
+}
+
+/*
+ * If we inherit events we want to return the parent event id
+ * to userspace.
+ */
+static u64 primary_event_id(struct perf_event *event)
+{
+	u64 id = event->id;
+
+	if (event->parent)
+		id = event->parent->id;
+
+	return id;
+}
+
+/*
+ * Get the perf_event_context for a task and lock it.
+ * This has to cope with with the fact that until it is locked,
+ * the context could get moved to another task.
+ */
+static struct perf_event_context *
+perf_lock_task_context(struct task_struct *task, unsigned long *flags)
+{
+	struct perf_event_context *ctx;
+
+	rcu_read_lock();
+ retry:
+	ctx = rcu_dereference(task->perf_event_ctxp);
+	if (ctx) {
+		/*
+		 * If this context is a clone of another, it might
+		 * get swapped for another underneath us by
+		 * perf_event_task_sched_out, though the
+		 * rcu_read_lock() protects us from any context
+		 * getting freed.  Lock the context and check if it
+		 * got swapped before we could get the lock, and retry
+		 * if so.  If we locked the right context, then it
+		 * can't get swapped on us any more.
+		 */
+		spin_lock_irqsave(&ctx->lock, *flags);
+		if (ctx != rcu_dereference(task->perf_event_ctxp)) {
+			spin_unlock_irqrestore(&ctx->lock, *flags);
+			goto retry;
+		}
+
+		if (!atomic_inc_not_zero(&ctx->refcount)) {
+			spin_unlock_irqrestore(&ctx->lock, *flags);
+			ctx = NULL;
+		}
+	}
+	rcu_read_unlock();
+	return ctx;
+}
+
+/*
+ * Get the context for a task and increment its pin_count so it
+ * can't get swapped to another task.  This also increments its
+ * reference count so that the context can't get freed.
+ */
+static struct perf_event_context *perf_pin_task_context(struct task_struct *task)
+{
+	struct perf_event_context *ctx;
+	unsigned long flags;
+
+	ctx = perf_lock_task_context(task, &flags);
+	if (ctx) {
+		++ctx->pin_count;
+		spin_unlock_irqrestore(&ctx->lock, flags);
+	}
+	return ctx;
+}
+
+static void perf_unpin_context(struct perf_event_context *ctx)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&ctx->lock, flags);
+	--ctx->pin_count;
+	spin_unlock_irqrestore(&ctx->lock, flags);
+	put_ctx(ctx);
+}
+
+/*
+ * Add a event from the lists for its context.
+ * Must be called with ctx->mutex and ctx->lock held.
+ */
+static void
+list_add_event(struct perf_event *event, struct perf_event_context *ctx)
+{
+	struct perf_event *group_leader = event->group_leader;
+
+	/*
+	 * Depending on whether it is a standalone or sibling event,
+	 * add it straight to the context's event list, or to the group
+	 * leader's sibling list:
+	 */
+	if (group_leader == event)
+		list_add_tail(&event->group_entry, &ctx->group_list);
+	else {
+		list_add_tail(&event->group_entry, &group_leader->sibling_list);
+		group_leader->nr_siblings++;
+	}
+
+	list_add_rcu(&event->event_entry, &ctx->event_list);
+	ctx->nr_events++;
+	if (event->attr.inherit_stat)
+		ctx->nr_stat++;
+}
+
+/*
+ * Remove a event from the lists for its context.
+ * Must be called with ctx->mutex and ctx->lock held.
+ */
+static void
+list_del_event(struct perf_event *event, struct perf_event_context *ctx)
+{
+	struct perf_event *sibling, *tmp;
+
+	if (list_empty(&event->group_entry))
+		return;
+	ctx->nr_events--;
+	if (event->attr.inherit_stat)
+		ctx->nr_stat--;
+
+	list_del_init(&event->group_entry);
+	list_del_rcu(&event->event_entry);
+
+	if (event->group_leader != event)
+		event->group_leader->nr_siblings--;
+
+	/*
+	 * If this was a group event with sibling events then
+	 * upgrade the siblings to singleton events by adding them
+	 * to the context list directly:
+	 */
+	list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) {
+
+		list_move_tail(&sibling->group_entry, &ctx->group_list);
+		sibling->group_leader = sibling;
+	}
+}
+
+static void
+event_sched_out(struct perf_event *event,
+		  struct perf_cpu_context *cpuctx,
+		  struct perf_event_context *ctx)
+{
+	if (event->state != PERF_EVENT_STATE_ACTIVE)
+		return;
+
+	event->state = PERF_EVENT_STATE_INACTIVE;
+	if (event->pending_disable) {
+		event->pending_disable = 0;
+		event->state = PERF_EVENT_STATE_OFF;
+	}
+	event->tstamp_stopped = ctx->time;
+	event->pmu->disable(event);
+	event->oncpu = -1;
+
+	if (!is_software_event(event))
+		cpuctx->active_oncpu--;
+	ctx->nr_active--;
+	if (event->attr.exclusive || !cpuctx->active_oncpu)
+		cpuctx->exclusive = 0;
+}
+
+static void
+group_sched_out(struct perf_event *group_event,
+		struct perf_cpu_context *cpuctx,
+		struct perf_event_context *ctx)
+{
+	struct perf_event *event;
+
+	if (group_event->state != PERF_EVENT_STATE_ACTIVE)
+		return;
+
+	event_sched_out(group_event, cpuctx, ctx);
+
+	/*
+	 * Schedule out siblings (if any):
+	 */
+	list_for_each_entry(event, &group_event->sibling_list, group_entry)
+		event_sched_out(event, cpuctx, ctx);
+
+	if (group_event->attr.exclusive)
+		cpuctx->exclusive = 0;
+}
+
+/*
+ * Cross CPU call to remove a performance event
+ *
+ * We disable the event on the hardware level first. After that we
+ * remove it from the context list.
+ */
+static void __perf_event_remove_from_context(void *info)
+{
+	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+	struct perf_event *event = info;
+	struct perf_event_context *ctx = event->ctx;
+
+	/*
+	 * If this is a task context, we need to check whether it is
+	 * the current task context of this cpu. If not it has been
+	 * scheduled out before the smp call arrived.
+	 */
+	if (ctx->task && cpuctx->task_ctx != ctx)
+		return;
+
+	spin_lock(&ctx->lock);
+	/*
+	 * Protect the list operation against NMI by disabling the
+	 * events on a global level.
+	 */
+	perf_disable();
+
+	event_sched_out(event, cpuctx, ctx);
+
+	list_del_event(event, ctx);
+
+	if (!ctx->task) {
+		/*
+		 * Allow more per task events with respect to the
+		 * reservation:
+		 */
+		cpuctx->max_pertask =
+			min(perf_max_events - ctx->nr_events,
+			    perf_max_events - perf_reserved_percpu);
+	}
+
+	perf_enable();
+	spin_unlock(&ctx->lock);
+}
+
+
+/*
+ * Remove the event from a task's (or a CPU's) list of events.
+ *
+ * Must be called with ctx->mutex held.
+ *
+ * CPU events are removed with a smp call. For task events we only
+ * call when the task is on a CPU.
+ *
+ * If event->ctx is a cloned context, callers must make sure that
+ * every task struct that event->ctx->task could possibly point to
+ * remains valid.  This is OK when called from perf_release since
+ * that only calls us on the top-level context, which can't be a clone.
+ * When called from perf_event_exit_task, it's OK because the
+ * context has been detached from its task.
+ */
+static void perf_event_remove_from_context(struct perf_event *event)
+{
+	struct perf_event_context *ctx = event->ctx;
+	struct task_struct *task = ctx->task;
+
+	if (!task) {
+		/*
+		 * Per cpu events are removed via an smp call and
+		 * the removal is always sucessful.
+		 */
+		smp_call_function_single(event->cpu,
+					 __perf_event_remove_from_context,
+					 event, 1);
+		return;
+	}
+
+retry:
+	task_oncpu_function_call(task, __perf_event_remove_from_context,
+				 event);
+
+	spin_lock_irq(&ctx->lock);
+	/*
+	 * If the context is active we need to retry the smp call.
+	 */
+	if (ctx->nr_active && !list_empty(&event->group_entry)) {
+		spin_unlock_irq(&ctx->lock);
+		goto retry;
+	}
+
+	/*
+	 * The lock prevents that this context is scheduled in so we
+	 * can remove the event safely, if the call above did not
+	 * succeed.
+	 */
+	if (!list_empty(&event->group_entry)) {
+		list_del_event(event, ctx);
+	}
+	spin_unlock_irq(&ctx->lock);
+}
+
+static inline u64 perf_clock(void)
+{
+	return cpu_clock(smp_processor_id());
+}
+
+/*
+ * Update the record of the current time in a context.
+ */
+static void update_context_time(struct perf_event_context *ctx)
+{
+	u64 now = perf_clock();
+
+	ctx->time += now - ctx->timestamp;
+	ctx->timestamp = now;
+}
+
+/*
+ * Update the total_time_enabled and total_time_running fields for a event.
+ */
+static void update_event_times(struct perf_event *event)
+{
+	struct perf_event_context *ctx = event->ctx;
+	u64 run_end;
+
+	if (event->state < PERF_EVENT_STATE_INACTIVE ||
+	    event->group_leader->state < PERF_EVENT_STATE_INACTIVE)
+		return;
+
+	event->total_time_enabled = ctx->time - event->tstamp_enabled;
+
+	if (event->state == PERF_EVENT_STATE_INACTIVE)
+		run_end = event->tstamp_stopped;
+	else
+		run_end = ctx->time;
+
+	event->total_time_running = run_end - event->tstamp_running;
+}
+
+/*
+ * Update total_time_enabled and total_time_running for all events in a group.
+ */
+static void update_group_times(struct perf_event *leader)
+{
+	struct perf_event *event;
+
+	update_event_times(leader);
+	list_for_each_entry(event, &leader->sibling_list, group_entry)
+		update_event_times(event);
+}
+
+/*
+ * Cross CPU call to disable a performance event
+ */
+static void __perf_event_disable(void *info)
+{
+	struct perf_event *event = info;
+	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+	struct perf_event_context *ctx = event->ctx;
+
+	/*
+	 * If this is a per-task event, need to check whether this
+	 * event's task is the current task on this cpu.
+	 */
+	if (ctx->task && cpuctx->task_ctx != ctx)
+		return;
+
+	spin_lock(&ctx->lock);
+
+	/*
+	 * If the event is on, turn it off.
+	 * If it is in error state, leave it in error state.
+	 */
+	if (event->state >= PERF_EVENT_STATE_INACTIVE) {
+		update_context_time(ctx);
+		update_group_times(event);
+		if (event == event->group_leader)
+			group_sched_out(event, cpuctx, ctx);
+		else
+			event_sched_out(event, cpuctx, ctx);
+		event->state = PERF_EVENT_STATE_OFF;
+	}
+
+	spin_unlock(&ctx->lock);
+}
+
+/*
+ * Disable a event.
+ *
+ * If event->ctx is a cloned context, callers must make sure that
+ * every task struct that event->ctx->task could possibly point to
+ * remains valid.  This condition is satisifed when called through
+ * perf_event_for_each_child or perf_event_for_each because they
+ * hold the top-level event's child_mutex, so any descendant that
+ * goes to exit will block in sync_child_event.
+ * When called from perf_pending_event it's OK because event->ctx
+ * is the current context on this CPU and preemption is disabled,
+ * hence we can't get into perf_event_task_sched_out for this context.
+ */
+static void perf_event_disable(struct perf_event *event)
+{
+	struct perf_event_context *ctx = event->ctx;
+	struct task_struct *task = ctx->task;
+
+	if (!task) {
+		/*
+		 * Disable the event on the cpu that it's on
+		 */
+		smp_call_function_single(event->cpu, __perf_event_disable,
+					 event, 1);
+		return;
+	}
+
+ retry:
+	task_oncpu_function_call(task, __perf_event_disable, event);
+
+	spin_lock_irq(&ctx->lock);
+	/*
+	 * If the event is still active, we need to retry the cross-call.
+	 */
+	if (event->state == PERF_EVENT_STATE_ACTIVE) {
+		spin_unlock_irq(&ctx->lock);
+		goto retry;
+	}
+
+	/*
+	 * Since we have the lock this context can't be scheduled
+	 * in, so we can change the state safely.
+	 */
+	if (event->state == PERF_EVENT_STATE_INACTIVE) {
+		update_group_times(event);
+		event->state = PERF_EVENT_STATE_OFF;
+	}
+
+	spin_unlock_irq(&ctx->lock);
+}
+
+static int
+event_sched_in(struct perf_event *event,
+		 struct perf_cpu_context *cpuctx,
+		 struct perf_event_context *ctx,
+		 int cpu)
+{
+	if (event->state <= PERF_EVENT_STATE_OFF)
+		return 0;
+
+	event->state = PERF_EVENT_STATE_ACTIVE;
+	event->oncpu = cpu;	/* TODO: put 'cpu' into cpuctx->cpu */
+	/*
+	 * The new state must be visible before we turn it on in the hardware:
+	 */
+	smp_wmb();
+
+	if (event->pmu->enable(event)) {
+		event->state = PERF_EVENT_STATE_INACTIVE;
+		event->oncpu = -1;
+		return -EAGAIN;
+	}
+
+	event->tstamp_running += ctx->time - event->tstamp_stopped;
+
+	if (!is_software_event(event))
+		cpuctx->active_oncpu++;
+	ctx->nr_active++;
+
+	if (event->attr.exclusive)
+		cpuctx->exclusive = 1;
+
+	return 0;
+}
+
+static int
+group_sched_in(struct perf_event *group_event,
+	       struct perf_cpu_context *cpuctx,
+	       struct perf_event_context *ctx,
+	       int cpu)
+{
+	struct perf_event *event, *partial_group;
+	int ret;
+
+	if (group_event->state == PERF_EVENT_STATE_OFF)
+		return 0;
+
+	ret = hw_perf_group_sched_in(group_event, cpuctx, ctx, cpu);
+	if (ret)
+		return ret < 0 ? ret : 0;
+
+	if (event_sched_in(group_event, cpuctx, ctx, cpu))
+		return -EAGAIN;
+
+	/*
+	 * Schedule in siblings as one group (if any):
+	 */
+	list_for_each_entry(event, &group_event->sibling_list, group_entry) {
+		if (event_sched_in(event, cpuctx, ctx, cpu)) {
+			partial_group = event;
+			goto group_error;
+		}
+	}
+
+	return 0;
+
+group_error:
+	/*
+	 * Groups can be scheduled in as one unit only, so undo any
+	 * partial group before returning:
+	 */
+	list_for_each_entry(event, &group_event->sibling_list, group_entry) {
+		if (event == partial_group)
+			break;
+		event_sched_out(event, cpuctx, ctx);
+	}
+	event_sched_out(group_event, cpuctx, ctx);
+
+	return -EAGAIN;
+}
+
+/*
+ * Return 1 for a group consisting entirely of software events,
+ * 0 if the group contains any hardware events.
+ */
+static int is_software_only_group(struct perf_event *leader)
+{
+	struct perf_event *event;
+
+	if (!is_software_event(leader))
+		return 0;
+
+	list_for_each_entry(event, &leader->sibling_list, group_entry)
+		if (!is_software_event(event))
+			return 0;
+
+	return 1;
+}
+
+/*
+ * Work out whether we can put this event group on the CPU now.
+ */
+static int group_can_go_on(struct perf_event *event,
+			   struct perf_cpu_context *cpuctx,
+			   int can_add_hw)
+{
+	/*
+	 * Groups consisting entirely of software events can always go on.
+	 */
+	if (is_software_only_group(event))
+		return 1;
+	/*
+	 * If an exclusive group is already on, no other hardware
+	 * events can go on.
+	 */
+	if (cpuctx->exclusive)
+		return 0;
+	/*
+	 * If this group is exclusive and there are already
+	 * events on the CPU, it can't go on.
+	 */
+	if (event->attr.exclusive && cpuctx->active_oncpu)
+		return 0;
+	/*
+	 * Otherwise, try to add it if all previous groups were able
+	 * to go on.
+	 */
+	return can_add_hw;
+}
+
+static void add_event_to_ctx(struct perf_event *event,
+			       struct perf_event_context *ctx)
+{
+	list_add_event(event, ctx);
+	event->tstamp_enabled = ctx->time;
+	event->tstamp_running = ctx->time;
+	event->tstamp_stopped = ctx->time;
+}
+
+/*
+ * Cross CPU call to install and enable a performance event
+ *
+ * Must be called with ctx->mutex held
+ */
+static void __perf_install_in_context(void *info)
+{
+	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+	struct perf_event *event = info;
+	struct perf_event_context *ctx = event->ctx;
+	struct perf_event *leader = event->group_leader;
+	int cpu = smp_processor_id();
+	int err;
+
+	/*
+	 * If this is a task context, we need to check whether it is
+	 * the current task context of this cpu. If not it has been
+	 * scheduled out before the smp call arrived.
+	 * Or possibly this is the right context but it isn't
+	 * on this cpu because it had no events.
+	 */
+	if (ctx->task && cpuctx->task_ctx != ctx) {
+		if (cpuctx->task_ctx || ctx->task != current)
+			return;
+		cpuctx->task_ctx = ctx;
+	}
+
+	spin_lock(&ctx->lock);
+	ctx->is_active = 1;
+	update_context_time(ctx);
+
+	/*
+	 * Protect the list operation against NMI by disabling the
+	 * events on a global level. NOP for non NMI based events.
+	 */
+	perf_disable();
+
+	add_event_to_ctx(event, ctx);
+
+	/*
+	 * Don't put the event on if it is disabled or if
+	 * it is in a group and the group isn't on.
+	 */
+	if (event->state != PERF_EVENT_STATE_INACTIVE ||
+	    (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE))
+		goto unlock;
+
+	/*
+	 * An exclusive event can't go on if there are already active
+	 * hardware events, and no hardware event can go on if there
+	 * is already an exclusive event on.
+	 */
+	if (!group_can_go_on(event, cpuctx, 1))
+		err = -EEXIST;
+	else
+		err = event_sched_in(event, cpuctx, ctx, cpu);
+
+	if (err) {
+		/*
+		 * This event couldn't go on.  If it is in a group
+		 * then we have to pull the whole group off.
+		 * If the event group is pinned then put it in error state.
+		 */
+		if (leader != event)
+			group_sched_out(leader, cpuctx, ctx);
+		if (leader->attr.pinned) {
+			update_group_times(leader);
+			leader->state = PERF_EVENT_STATE_ERROR;
+		}
+	}
+
+	if (!err && !ctx->task && cpuctx->max_pertask)
+		cpuctx->max_pertask--;
+
+ unlock:
+	perf_enable();
+
+	spin_unlock(&ctx->lock);
+}
+
+/*
+ * Attach a performance event to a context
+ *
+ * First we add the event to the list with the hardware enable bit
+ * in event->hw_config cleared.
+ *
+ * If the event is attached to a task which is on a CPU we use a smp
+ * call to enable it in the task context. The task might have been
+ * scheduled away, but we check this in the smp call again.
+ *
+ * Must be called with ctx->mutex held.
+ */
+static void
+perf_install_in_context(struct perf_event_context *ctx,
+			struct perf_event *event,
+			int cpu)
+{
+	struct task_struct *task = ctx->task;
+
+	if (!task) {
+		/*
+		 * Per cpu events are installed via an smp call and
+		 * the install is always sucessful.
+		 */
+		smp_call_function_single(cpu, __perf_install_in_context,
+					 event, 1);
+		return;
+	}
+
+retry:
+	task_oncpu_function_call(task, __perf_install_in_context,
+				 event);
+
+	spin_lock_irq(&ctx->lock);
+	/*
+	 * we need to retry the smp call.
+	 */
+	if (ctx->is_active && list_empty(&event->group_entry)) {
+		spin_unlock_irq(&ctx->lock);
+		goto retry;
+	}
+
+	/*
+	 * The lock prevents that this context is scheduled in so we
+	 * can add the event safely, if it the call above did not
+	 * succeed.
+	 */
+	if (list_empty(&event->group_entry))
+		add_event_to_ctx(event, ctx);
+	spin_unlock_irq(&ctx->lock);
+}
+
+/*
+ * Put a event into inactive state and update time fields.
+ * Enabling the leader of a group effectively enables all
+ * the group members that aren't explicitly disabled, so we
+ * have to update their ->tstamp_enabled also.
+ * Note: this works for group members as well as group leaders
+ * since the non-leader members' sibling_lists will be empty.
+ */
+static void __perf_event_mark_enabled(struct perf_event *event,
+					struct perf_event_context *ctx)
+{
+	struct perf_event *sub;
+
+	event->state = PERF_EVENT_STATE_INACTIVE;
+	event->tstamp_enabled = ctx->time - event->total_time_enabled;
+	list_for_each_entry(sub, &event->sibling_list, group_entry)
+		if (sub->state >= PERF_EVENT_STATE_INACTIVE)
+			sub->tstamp_enabled =
+				ctx->time - sub->total_time_enabled;
+}
+
+/*
+ * Cross CPU call to enable a performance event
+ */
+static void __perf_event_enable(void *info)
+{
+	struct perf_event *event = info;
+	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+	struct perf_event_context *ctx = event->ctx;
+	struct perf_event *leader = event->group_leader;
+	int err;
+
+	/*
+	 * If this is a per-task event, need to check whether this
+	 * event's task is the current task on this cpu.
+	 */
+	if (ctx->task && cpuctx->task_ctx != ctx) {
+		if (cpuctx->task_ctx || ctx->task != current)
+			return;
+		cpuctx->task_ctx = ctx;
+	}
+
+	spin_lock(&ctx->lock);
+	ctx->is_active = 1;
+	update_context_time(ctx);
+
+	if (event->state >= PERF_EVENT_STATE_INACTIVE)
+		goto unlock;
+	__perf_event_mark_enabled(event, ctx);
+
+	/*
+	 * If the event is in a group and isn't the group leader,
+	 * then don't put it on unless the group is on.
+	 */
+	if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE)
+		goto unlock;
+
+	if (!group_can_go_on(event, cpuctx, 1)) {
+		err = -EEXIST;
+	} else {
+		perf_disable();
+		if (event == leader)
+			err = group_sched_in(event, cpuctx, ctx,
+					     smp_processor_id());
+		else
+			err = event_sched_in(event, cpuctx, ctx,
+					       smp_processor_id());
+		perf_enable();
+	}
+
+	if (err) {
+		/*
+		 * If this event can't go on and it's part of a
+		 * group, then the whole group has to come off.
+		 */
+		if (leader != event)
+			group_sched_out(leader, cpuctx, ctx);
+		if (leader->attr.pinned) {
+			update_group_times(leader);
+			leader->state = PERF_EVENT_STATE_ERROR;
+		}
+	}
+
+ unlock:
+	spin_unlock(&ctx->lock);
+}
+
+/*
+ * Enable a event.
+ *
+ * If event->ctx is a cloned context, callers must make sure that
+ * every task struct that event->ctx->task could possibly point to
+ * remains valid.  This condition is satisfied when called through
+ * perf_event_for_each_child or perf_event_for_each as described
+ * for perf_event_disable.
+ */
+static void perf_event_enable(struct perf_event *event)
+{
+	struct perf_event_context *ctx = event->ctx;
+	struct task_struct *task = ctx->task;
+
+	if (!task) {
+		/*
+		 * Enable the event on the cpu that it's on
+		 */
+		smp_call_function_single(event->cpu, __perf_event_enable,
+					 event, 1);
+		return;
+	}
+
+	spin_lock_irq(&ctx->lock);
+	if (event->state >= PERF_EVENT_STATE_INACTIVE)
+		goto out;
+
+	/*
+	 * If the event is in error state, clear that first.
+	 * That way, if we see the event in error state below, we
+	 * know that it has gone back into error state, as distinct
+	 * from the task having been scheduled away before the
+	 * cross-call arrived.
+	 */
+	if (event->state == PERF_EVENT_STATE_ERROR)
+		event->state = PERF_EVENT_STATE_OFF;
+
+ retry:
+	spin_unlock_irq(&ctx->lock);
+	task_oncpu_function_call(task, __perf_event_enable, event);
+
+	spin_lock_irq(&ctx->lock);
+
+	/*
+	 * If the context is active and the event is still off,
+	 * we need to retry the cross-call.
+	 */
+	if (ctx->is_active && event->state == PERF_EVENT_STATE_OFF)
+		goto retry;
+
+	/*
+	 * Since we have the lock this context can't be scheduled
+	 * in, so we can change the state safely.
+	 */
+	if (event->state == PERF_EVENT_STATE_OFF)
+		__perf_event_mark_enabled(event, ctx);
+
+ out:
+	spin_unlock_irq(&ctx->lock);
+}
+
+static int perf_event_refresh(struct perf_event *event, int refresh)
+{
+	/*
+	 * not supported on inherited events
+	 */
+	if (event->attr.inherit)
+		return -EINVAL;
+
+	atomic_add(refresh, &event->event_limit);
+	perf_event_enable(event);
+
+	return 0;
+}
+
+void __perf_event_sched_out(struct perf_event_context *ctx,
+			      struct perf_cpu_context *cpuctx)
+{
+	struct perf_event *event;
+
+	spin_lock(&ctx->lock);
+	ctx->is_active = 0;
+	if (likely(!ctx->nr_events))
+		goto out;
+	update_context_time(ctx);
+
+	perf_disable();
+	if (ctx->nr_active) {
+		list_for_each_entry(event, &ctx->group_list, group_entry) {
+			if (event != event->group_leader)
+				event_sched_out(event, cpuctx, ctx);
+			else
+				group_sched_out(event, cpuctx, ctx);
+		}
+	}
+	perf_enable();
+ out:
+	spin_unlock(&ctx->lock);
+}
+
+/*
+ * Test whether two contexts are equivalent, i.e. whether they
+ * have both been cloned from the same version of the same context
+ * and they both have the same number of enabled events.
+ * If the number of enabled events is the same, then the set
+ * of enabled events should be the same, because these are both
+ * inherited contexts, therefore we can't access individual events
+ * in them directly with an fd; we can only enable/disable all
+ * events via prctl, or enable/disable all events in a family
+ * via ioctl, which will have the same effect on both contexts.
+ */
+static int context_equiv(struct perf_event_context *ctx1,
+			 struct perf_event_context *ctx2)
+{
+	return ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx
+		&& ctx1->parent_gen == ctx2->parent_gen
+		&& !ctx1->pin_count && !ctx2->pin_count;
+}
+
+static void __perf_event_read(void *event);
+
+static void __perf_event_sync_stat(struct perf_event *event,
+				     struct perf_event *next_event)
+{
+	u64 value;
+
+	if (!event->attr.inherit_stat)
+		return;
+
+	/*
+	 * Update the event value, we cannot use perf_event_read()
+	 * because we're in the middle of a context switch and have IRQs
+	 * disabled, which upsets smp_call_function_single(), however
+	 * we know the event must be on the current CPU, therefore we
+	 * don't need to use it.
+	 */
+	switch (event->state) {
+	case PERF_EVENT_STATE_ACTIVE:
+		__perf_event_read(event);
+		break;
+
+	case PERF_EVENT_STATE_INACTIVE:
+		update_event_times(event);
+		break;
+
+	default:
+		break;
+	}
+
+	/*
+	 * In order to keep per-task stats reliable we need to flip the event
+	 * values when we flip the contexts.
+	 */
+	value = atomic64_read(&next_event->count);
+	value = atomic64_xchg(&event->count, value);
+	atomic64_set(&next_event->count, value);
+
+	swap(event->total_time_enabled, next_event->total_time_enabled);
+	swap(event->total_time_running, next_event->total_time_running);
+
+	/*
+	 * Since we swizzled the values, update the user visible data too.
+	 */
+	perf_event_update_userpage(event);
+	perf_event_update_userpage(next_event);
+}
+
+#define list_next_entry(pos, member) \
+	list_entry(pos->member.next, typeof(*pos), member)
+
+static void perf_event_sync_stat(struct perf_event_context *ctx,
+				   struct perf_event_context *next_ctx)
+{
+	struct perf_event *event, *next_event;
+
+	if (!ctx->nr_stat)
+		return;
+
+	event = list_first_entry(&ctx->event_list,
+				   struct perf_event, event_entry);
+
+	next_event = list_first_entry(&next_ctx->event_list,
+					struct perf_event, event_entry);
+
+	while (&event->event_entry != &ctx->event_list &&
+	       &next_event->event_entry != &next_ctx->event_list) {
+
+		__perf_event_sync_stat(event, next_event);
+
+		event = list_next_entry(event, event_entry);
+		next_event = list_next_entry(next_event, event_entry);
+	}
+}
+
+/*
+ * Called from scheduler to remove the events of the current task,
+ * with interrupts disabled.
+ *
+ * We stop each event and update the event value in event->count.
+ *
+ * This does not protect us against NMI, but disable()
+ * sets the disabled bit in the control field of event _before_
+ * accessing the event control register. If a NMI hits, then it will
+ * not restart the event.
+ */
+void perf_event_task_sched_out(struct task_struct *task,
+				 struct task_struct *next, int cpu)
+{
+	struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
+	struct perf_event_context *ctx = task->perf_event_ctxp;
+	struct perf_event_context *next_ctx;
+	struct perf_event_context *parent;
+	struct pt_regs *regs;
+	int do_switch = 1;
+
+	regs = task_pt_regs(task);
+	perf_sw_event(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 1, regs, 0);
+
+	if (likely(!ctx || !cpuctx->task_ctx))
+		return;
+
+	update_context_time(ctx);
+
+	rcu_read_lock();
+	parent = rcu_dereference(ctx->parent_ctx);
+	next_ctx = next->perf_event_ctxp;
+	if (parent && next_ctx &&
+	    rcu_dereference(next_ctx->parent_ctx) == parent) {
+		/*
+		 * Looks like the two contexts are clones, so we might be
+		 * able to optimize the context switch.  We lock both
+		 * contexts and check that they are clones under the
+		 * lock (including re-checking that neither has been
+		 * uncloned in the meantime).  It doesn't matter which
+		 * order we take the locks because no other cpu could
+		 * be trying to lock both of these tasks.
+		 */
+		spin_lock(&ctx->lock);
+		spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING);
+		if (context_equiv(ctx, next_ctx)) {
+			/*
+			 * XXX do we need a memory barrier of sorts
+			 * wrt to rcu_dereference() of perf_event_ctxp
+			 */
+			task->perf_event_ctxp = next_ctx;
+			next->perf_event_ctxp = ctx;
+			ctx->task = next;
+			next_ctx->task = task;
+			do_switch = 0;
+
+			perf_event_sync_stat(ctx, next_ctx);
+		}
+		spin_unlock(&next_ctx->lock);
+		spin_unlock(&ctx->lock);
+	}
+	rcu_read_unlock();
+
+	if (do_switch) {
+		__perf_event_sched_out(ctx, cpuctx);
+		cpuctx->task_ctx = NULL;
+	}
+}
+
+/*
+ * Called with IRQs disabled
+ */
+static void __perf_event_task_sched_out(struct perf_event_context *ctx)
+{
+	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+
+	if (!cpuctx->task_ctx)
+		return;
+
+	if (WARN_ON_ONCE(ctx != cpuctx->task_ctx))
+		return;
+
+	__perf_event_sched_out(ctx, cpuctx);
+	cpuctx->task_ctx = NULL;
+}
+
+/*
+ * Called with IRQs disabled
+ */
+static void perf_event_cpu_sched_out(struct perf_cpu_context *cpuctx)
+{
+	__perf_event_sched_out(&cpuctx->ctx, cpuctx);
+}
+
+static void
+__perf_event_sched_in(struct perf_event_context *ctx,
+			struct perf_cpu_context *cpuctx, int cpu)
+{
+	struct perf_event *event;
+	int can_add_hw = 1;
+
+	spin_lock(&ctx->lock);
+	ctx->is_active = 1;
+	if (likely(!ctx->nr_events))
+		goto out;
+
+	ctx->timestamp = perf_clock();
+
+	perf_disable();
+
+	/*
+	 * First go through the list and put on any pinned groups
+	 * in order to give them the best chance of going on.
+	 */
+	list_for_each_entry(event, &ctx->group_list, group_entry) {
+		if (event->state <= PERF_EVENT_STATE_OFF ||
+		    !event->attr.pinned)
+			continue;
+		if (event->cpu != -1 && event->cpu != cpu)
+			continue;
+
+		if (event != event->group_leader)
+			event_sched_in(event, cpuctx, ctx, cpu);
+		else {
+			if (group_can_go_on(event, cpuctx, 1))
+				group_sched_in(event, cpuctx, ctx, cpu);
+		}
+
+		/*
+		 * If this pinned group hasn't been scheduled,
+		 * put it in error state.
+		 */
+		if (event->state == PERF_EVENT_STATE_INACTIVE) {
+			update_group_times(event);
+			event->state = PERF_EVENT_STATE_ERROR;
+		}
+	}
+
+	list_for_each_entry(event, &ctx->group_list, group_entry) {
+		/*
+		 * Ignore events in OFF or ERROR state, and
+		 * ignore pinned events since we did them already.
+		 */
+		if (event->state <= PERF_EVENT_STATE_OFF ||
+		    event->attr.pinned)
+			continue;
+
+		/*
+		 * Listen to the 'cpu' scheduling filter constraint
+		 * of events:
+		 */
+		if (event->cpu != -1 && event->cpu != cpu)
+			continue;
+
+		if (event != event->group_leader) {
+			if (event_sched_in(event, cpuctx, ctx, cpu))
+				can_add_hw = 0;
+		} else {
+			if (group_can_go_on(event, cpuctx, can_add_hw)) {
+				if (group_sched_in(event, cpuctx, ctx, cpu))
+					can_add_hw = 0;
+			}
+		}
+	}
+	perf_enable();
+ out:
+	spin_unlock(&ctx->lock);
+}
+
+/*
+ * Called from scheduler to add the events of the current task
+ * with interrupts disabled.
+ *
+ * We restore the event value and then enable it.
+ *
+ * This does not protect us against NMI, but enable()
+ * sets the enabled bit in the control field of event _before_
+ * accessing the event control register. If a NMI hits, then it will
+ * keep the event running.
+ */
+void perf_event_task_sched_in(struct task_struct *task, int cpu)
+{
+	struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
+	struct perf_event_context *ctx = task->perf_event_ctxp;
+
+	if (likely(!ctx))
+		return;
+	if (cpuctx->task_ctx == ctx)
+		return;
+	__perf_event_sched_in(ctx, cpuctx, cpu);
+	cpuctx->task_ctx = ctx;
+}
+
+static void perf_event_cpu_sched_in(struct perf_cpu_context *cpuctx, int cpu)
+{
+	struct perf_event_context *ctx = &cpuctx->ctx;
+
+	__perf_event_sched_in(ctx, cpuctx, cpu);
+}
+
+#define MAX_INTERRUPTS (~0ULL)
+
+static void perf_log_throttle(struct perf_event *event, int enable);
+
+static void perf_adjust_period(struct perf_event *event, u64 events)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	u64 period, sample_period;
+	s64 delta;
+
+	events *= hwc->sample_period;
+	period = div64_u64(events, event->attr.sample_freq);
+
+	delta = (s64)(period - hwc->sample_period);
+	delta = (delta + 7) / 8; /* low pass filter */
+
+	sample_period = hwc->sample_period + delta;
+
+	if (!sample_period)
+		sample_period = 1;
+
+	hwc->sample_period = sample_period;
+}
+
+static void perf_ctx_adjust_freq(struct perf_event_context *ctx)
+{
+	struct perf_event *event;
+	struct hw_perf_event *hwc;
+	u64 interrupts, freq;
+
+	spin_lock(&ctx->lock);
+	list_for_each_entry(event, &ctx->group_list, group_entry) {
+		if (event->state != PERF_EVENT_STATE_ACTIVE)
+			continue;
+
+		hwc = &event->hw;
+
+		interrupts = hwc->interrupts;
+		hwc->interrupts = 0;
+
+		/*
+		 * unthrottle events on the tick
+		 */
+		if (interrupts == MAX_INTERRUPTS) {
+			perf_log_throttle(event, 1);
+			event->pmu->unthrottle(event);
+			interrupts = 2*sysctl_perf_event_sample_rate/HZ;
+		}
+
+		if (!event->attr.freq || !event->attr.sample_freq)
+			continue;
+
+		/*
+		 * if the specified freq < HZ then we need to skip ticks
+		 */
+		if (event->attr.sample_freq < HZ) {
+			freq = event->attr.sample_freq;
+
+			hwc->freq_count += freq;
+			hwc->freq_interrupts += interrupts;
+
+			if (hwc->freq_count < HZ)
+				continue;
+
+			interrupts = hwc->freq_interrupts;
+			hwc->freq_interrupts = 0;
+			hwc->freq_count -= HZ;
+		} else
+			freq = HZ;
+
+		perf_adjust_period(event, freq * interrupts);
+
+		/*
+		 * In order to avoid being stalled by an (accidental) huge
+		 * sample period, force reset the sample period if we didn't
+		 * get any events in this freq period.
+		 */
+		if (!interrupts) {
+			perf_disable();
+			event->pmu->disable(event);
+			atomic64_set(&hwc->period_left, 0);
+			event->pmu->enable(event);
+			perf_enable();
+		}
+	}
+	spin_unlock(&ctx->lock);
+}
+
+/*
+ * Round-robin a context's events:
+ */
+static void rotate_ctx(struct perf_event_context *ctx)
+{
+	struct perf_event *event;
+
+	if (!ctx->nr_events)
+		return;
+
+	spin_lock(&ctx->lock);
+	/*
+	 * Rotate the first entry last (works just fine for group events too):
+	 */
+	perf_disable();
+	list_for_each_entry(event, &ctx->group_list, group_entry) {
+		list_move_tail(&event->group_entry, &ctx->group_list);
+		break;
+	}
+	perf_enable();
+
+	spin_unlock(&ctx->lock);
+}
+
+void perf_event_task_tick(struct task_struct *curr, int cpu)
+{
+	struct perf_cpu_context *cpuctx;
+	struct perf_event_context *ctx;
+
+	if (!atomic_read(&nr_events))
+		return;
+
+	cpuctx = &per_cpu(perf_cpu_context, cpu);
+	ctx = curr->perf_event_ctxp;
+
+	perf_ctx_adjust_freq(&cpuctx->ctx);
+	if (ctx)
+		perf_ctx_adjust_freq(ctx);
+
+	perf_event_cpu_sched_out(cpuctx);
+	if (ctx)
+		__perf_event_task_sched_out(ctx);
+
+	rotate_ctx(&cpuctx->ctx);
+	if (ctx)
+		rotate_ctx(ctx);
+
+	perf_event_cpu_sched_in(cpuctx, cpu);
+	if (ctx)
+		perf_event_task_sched_in(curr, cpu);
+}
+
+/*
+ * Enable all of a task's events that have been marked enable-on-exec.
+ * This expects task == current.
+ */
+static void perf_event_enable_on_exec(struct task_struct *task)
+{
+	struct perf_event_context *ctx;
+	struct perf_event *event;
+	unsigned long flags;
+	int enabled = 0;
+
+	local_irq_save(flags);
+	ctx = task->perf_event_ctxp;
+	if (!ctx || !ctx->nr_events)
+		goto out;
+
+	__perf_event_task_sched_out(ctx);
+
+	spin_lock(&ctx->lock);
+
+	list_for_each_entry(event, &ctx->group_list, group_entry) {
+		if (!event->attr.enable_on_exec)
+			continue;
+		event->attr.enable_on_exec = 0;
+		if (event->state >= PERF_EVENT_STATE_INACTIVE)
+			continue;
+		__perf_event_mark_enabled(event, ctx);
+		enabled = 1;
+	}
+
+	/*
+	 * Unclone this context if we enabled any event.
+	 */
+	if (enabled)
+		unclone_ctx(ctx);
+
+	spin_unlock(&ctx->lock);
+
+	perf_event_task_sched_in(task, smp_processor_id());
+ out:
+	local_irq_restore(flags);
+}
+
+/*
+ * Cross CPU call to read the hardware event
+ */
+static void __perf_event_read(void *info)
+{
+	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+	struct perf_event *event = info;
+	struct perf_event_context *ctx = event->ctx;
+	unsigned long flags;
+
+	/*
+	 * If this is a task context, we need to check whether it is
+	 * the current task context of this cpu.  If not it has been
+	 * scheduled out before the smp call arrived.  In that case
+	 * event->count would have been updated to a recent sample
+	 * when the event was scheduled out.
+	 */
+	if (ctx->task && cpuctx->task_ctx != ctx)
+		return;
+
+	local_irq_save(flags);
+	if (ctx->is_active)
+		update_context_time(ctx);
+	event->pmu->read(event);
+	update_event_times(event);
+	local_irq_restore(flags);
+}
+
+static u64 perf_event_read(struct perf_event *event)
+{
+	/*
+	 * If event is enabled and currently active on a CPU, update the
+	 * value in the event structure:
+	 */
+	if (event->state == PERF_EVENT_STATE_ACTIVE) {
+		smp_call_function_single(event->oncpu,
+					 __perf_event_read, event, 1);
+	} else if (event->state == PERF_EVENT_STATE_INACTIVE) {
+		update_event_times(event);
+	}
+
+	return atomic64_read(&event->count);
+}
+
+/*
+ * Initialize the perf_event context in a task_struct:
+ */
+static void
+__perf_event_init_context(struct perf_event_context *ctx,
+			    struct task_struct *task)
+{
+	memset(ctx, 0, sizeof(*ctx));
+	spin_lock_init(&ctx->lock);
+	mutex_init(&ctx->mutex);
+	INIT_LIST_HEAD(&ctx->group_list);
+	INIT_LIST_HEAD(&ctx->event_list);
+	atomic_set(&ctx->refcount, 1);
+	ctx->task = task;
+}
+
+static struct perf_event_context *find_get_context(pid_t pid, int cpu)
+{
+	struct perf_event_context *ctx;
+	struct perf_cpu_context *cpuctx;
+	struct task_struct *task;
+	unsigned long flags;
+	int err;
+
+	/*
+	 * If cpu is not a wildcard then this is a percpu event:
+	 */
+	if (cpu != -1) {
+		/* Must be root to operate on a CPU event: */
+		if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN))
+			return ERR_PTR(-EACCES);
+
+		if (cpu < 0 || cpu > num_possible_cpus())
+			return ERR_PTR(-EINVAL);
+
+		/*
+		 * We could be clever and allow to attach a event to an
+		 * offline CPU and activate it when the CPU comes up, but
+		 * that's for later.
+		 */
+		if (!cpu_isset(cpu, cpu_online_map))
+			return ERR_PTR(-ENODEV);
+
+		cpuctx = &per_cpu(perf_cpu_context, cpu);
+		ctx = &cpuctx->ctx;
+		get_ctx(ctx);
+
+		return ctx;
+	}
+
+	rcu_read_lock();
+	if (!pid)
+		task = current;
+	else
+		task = find_task_by_vpid(pid);
+	if (task)
+		get_task_struct(task);
+	rcu_read_unlock();
+
+	if (!task)
+		return ERR_PTR(-ESRCH);
+
+	/*
+	 * Can't attach events to a dying task.
+	 */
+	err = -ESRCH;
+	if (task->flags & PF_EXITING)
+		goto errout;
+
+	/* Reuse ptrace permission checks for now. */
+	err = -EACCES;
+	if (!ptrace_may_access(task, PTRACE_MODE_READ))
+		goto errout;
+
+ retry:
+	ctx = perf_lock_task_context(task, &flags);
+	if (ctx) {
+		unclone_ctx(ctx);
+		spin_unlock_irqrestore(&ctx->lock, flags);
+	}
+
+	if (!ctx) {
+		ctx = kmalloc(sizeof(struct perf_event_context), GFP_KERNEL);
+		err = -ENOMEM;
+		if (!ctx)
+			goto errout;
+		__perf_event_init_context(ctx, task);
+		get_ctx(ctx);
+		if (cmpxchg(&task->perf_event_ctxp, NULL, ctx)) {
+			/*
+			 * We raced with some other task; use
+			 * the context they set.
+			 */
+			kfree(ctx);
+			goto retry;
+		}
+		get_task_struct(task);
+	}
+
+	put_task_struct(task);
+	return ctx;
+
+ errout:
+	put_task_struct(task);
+	return ERR_PTR(err);
+}
+
+static void free_event_rcu(struct rcu_head *head)
+{
+	struct perf_event *event;
+
+	event = container_of(head, struct perf_event, rcu_head);
+	if (event->ns)
+		put_pid_ns(event->ns);
+	kfree(event);
+}
+
+static void perf_pending_sync(struct perf_event *event);
+
+static void free_event(struct perf_event *event)
+{
+	perf_pending_sync(event);
+
+	if (!event->parent) {
+		atomic_dec(&nr_events);
+		if (event->attr.mmap)
+			atomic_dec(&nr_mmap_events);
+		if (event->attr.comm)
+			atomic_dec(&nr_comm_events);
+		if (event->attr.task)
+			atomic_dec(&nr_task_events);
+	}
+
+	if (event->output) {
+		fput(event->output->filp);
+		event->output = NULL;
+	}
+
+	if (event->destroy)
+		event->destroy(event);
+
+	put_ctx(event->ctx);
+	call_rcu(&event->rcu_head, free_event_rcu);
+}
+
+/*
+ * Called when the last reference to the file is gone.
+ */
+static int perf_release(struct inode *inode, struct file *file)
+{
+	struct perf_event *event = file->private_data;
+	struct perf_event_context *ctx = event->ctx;
+
+	file->private_data = NULL;
+
+	WARN_ON_ONCE(ctx->parent_ctx);
+	mutex_lock(&ctx->mutex);
+	perf_event_remove_from_context(event);
+	mutex_unlock(&ctx->mutex);
+
+	mutex_lock(&event->owner->perf_event_mutex);
+	list_del_init(&event->owner_entry);
+	mutex_unlock(&event->owner->perf_event_mutex);
+	put_task_struct(event->owner);
+
+	free_event(event);
+
+	return 0;
+}
+
+static int perf_event_read_size(struct perf_event *event)
+{
+	int entry = sizeof(u64); /* value */
+	int size = 0;
+	int nr = 1;
+
+	if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+		size += sizeof(u64);
+
+	if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+		size += sizeof(u64);
+
+	if (event->attr.read_format & PERF_FORMAT_ID)
+		entry += sizeof(u64);
+
+	if (event->attr.read_format & PERF_FORMAT_GROUP) {
+		nr += event->group_leader->nr_siblings;
+		size += sizeof(u64);
+	}
+
+	size += entry * nr;
+
+	return size;
+}
+
+static u64 perf_event_read_value(struct perf_event *event)
+{
+	struct perf_event *child;
+	u64 total = 0;
+
+	total += perf_event_read(event);
+	list_for_each_entry(child, &event->child_list, child_list)
+		total += perf_event_read(child);
+
+	return total;
+}
+
+static int perf_event_read_entry(struct perf_event *event,
+				   u64 read_format, char __user *buf)
+{
+	int n = 0, count = 0;
+	u64 values[2];
+
+	values[n++] = perf_event_read_value(event);
+	if (read_format & PERF_FORMAT_ID)
+		values[n++] = primary_event_id(event);
+
+	count = n * sizeof(u64);
+
+	if (copy_to_user(buf, values, count))
+		return -EFAULT;
+
+	return count;
+}
+
+static int perf_event_read_group(struct perf_event *event,
+				   u64 read_format, char __user *buf)
+{
+	struct perf_event *leader = event->group_leader, *sub;
+	int n = 0, size = 0, err = -EFAULT;
+	u64 values[3];
+
+	values[n++] = 1 + leader->nr_siblings;
+	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
+		values[n++] = leader->total_time_enabled +
+			atomic64_read(&leader->child_total_time_enabled);
+	}
+	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
+		values[n++] = leader->total_time_running +
+			atomic64_read(&leader->child_total_time_running);
+	}
+
+	size = n * sizeof(u64);
+
+	if (copy_to_user(buf, values, size))
+		return -EFAULT;
+
+	err = perf_event_read_entry(leader, read_format, buf + size);
+	if (err < 0)
+		return err;
+
+	size += err;
+
+	list_for_each_entry(sub, &leader->sibling_list, group_entry) {
+		err = perf_event_read_entry(sub, read_format,
+				buf + size);
+		if (err < 0)
+			return err;
+
+		size += err;
+	}
+
+	return size;
+}
+
+static int perf_event_read_one(struct perf_event *event,
+				 u64 read_format, char __user *buf)
+{
+	u64 values[4];
+	int n = 0;
+
+	values[n++] = perf_event_read_value(event);
+	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
+		values[n++] = event->total_time_enabled +
+			atomic64_read(&event->child_total_time_enabled);
+	}
+	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
+		values[n++] = event->total_time_running +
+			atomic64_read(&event->child_total_time_running);
+	}
+	if (read_format & PERF_FORMAT_ID)
+		values[n++] = primary_event_id(event);
+
+	if (copy_to_user(buf, values, n * sizeof(u64)))
+		return -EFAULT;
+
+	return n * sizeof(u64);
+}
+
+/*
+ * Read the performance event - simple non blocking version for now
+ */
+static ssize_t
+perf_read_hw(struct perf_event *event, char __user *buf, size_t count)
+{
+	u64 read_format = event->attr.read_format;
+	int ret;
+
+	/*
+	 * Return end-of-file for a read on a event that is in
+	 * error state (i.e. because it was pinned but it couldn't be
+	 * scheduled on to the CPU at some point).
+	 */
+	if (event->state == PERF_EVENT_STATE_ERROR)
+		return 0;
+
+	if (count < perf_event_read_size(event))
+		return -ENOSPC;
+
+	WARN_ON_ONCE(event->ctx->parent_ctx);
+	mutex_lock(&event->child_mutex);
+	if (read_format & PERF_FORMAT_GROUP)
+		ret = perf_event_read_group(event, read_format, buf);
+	else
+		ret = perf_event_read_one(event, read_format, buf);
+	mutex_unlock(&event->child_mutex);
+
+	return ret;
+}
+
+static ssize_t
+perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
+{
+	struct perf_event *event = file->private_data;
+
+	return perf_read_hw(event, buf, count);
+}
+
+static unsigned int perf_poll(struct file *file, poll_table *wait)
+{
+	struct perf_event *event = file->private_data;
+	struct perf_mmap_data *data;
+	unsigned int events = POLL_HUP;
+
+	rcu_read_lock();
+	data = rcu_dereference(event->data);
+	if (data)
+		events = atomic_xchg(&data->poll, 0);
+	rcu_read_unlock();
+
+	poll_wait(file, &event->waitq, wait);
+
+	return events;
+}
+
+static void perf_event_reset(struct perf_event *event)
+{
+	(void)perf_event_read(event);
+	atomic64_set(&event->count, 0);
+	perf_event_update_userpage(event);
+}
+
+/*
+ * Holding the top-level event's child_mutex means that any
+ * descendant process that has inherited this event will block
+ * in sync_child_event if it goes to exit, thus satisfying the
+ * task existence requirements of perf_event_enable/disable.
+ */
+static void perf_event_for_each_child(struct perf_event *event,
+					void (*func)(struct perf_event *))
+{
+	struct perf_event *child;
+
+	WARN_ON_ONCE(event->ctx->parent_ctx);
+	mutex_lock(&event->child_mutex);
+	func(event);
+	list_for_each_entry(child, &event->child_list, child_list)
+		func(child);
+	mutex_unlock(&event->child_mutex);
+}
+
+static void perf_event_for_each(struct perf_event *event,
+				  void (*func)(struct perf_event *))
+{
+	struct perf_event_context *ctx = event->ctx;
+	struct perf_event *sibling;
+
+	WARN_ON_ONCE(ctx->parent_ctx);
+	mutex_lock(&ctx->mutex);
+	event = event->group_leader;
+
+	perf_event_for_each_child(event, func);
+	func(event);
+	list_for_each_entry(sibling, &event->sibling_list, group_entry)
+		perf_event_for_each_child(event, func);
+	mutex_unlock(&ctx->mutex);
+}
+
+static int perf_event_period(struct perf_event *event, u64 __user *arg)
+{
+	struct perf_event_context *ctx = event->ctx;
+	unsigned long size;
+	int ret = 0;
+	u64 value;
+
+	if (!event->attr.sample_period)
+		return -EINVAL;
+
+	size = copy_from_user(&value, arg, sizeof(value));
+	if (size != sizeof(value))
+		return -EFAULT;
+
+	if (!value)
+		return -EINVAL;
+
+	spin_lock_irq(&ctx->lock);
+	if (event->attr.freq) {
+		if (value > sysctl_perf_event_sample_rate) {
+			ret = -EINVAL;
+			goto unlock;
+		}
+
+		event->attr.sample_freq = value;
+	} else {
+		event->attr.sample_period = value;
+		event->hw.sample_period = value;
+	}
+unlock:
+	spin_unlock_irq(&ctx->lock);
+
+	return ret;
+}
+
+int perf_event_set_output(struct perf_event *event, int output_fd);
+
+static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	struct perf_event *event = file->private_data;
+	void (*func)(struct perf_event *);
+	u32 flags = arg;
+
+	switch (cmd) {
+	case PERF_EVENT_IOC_ENABLE:
+		func = perf_event_enable;
+		break;
+	case PERF_EVENT_IOC_DISABLE:
+		func = perf_event_disable;
+		break;
+	case PERF_EVENT_IOC_RESET:
+		func = perf_event_reset;
+		break;
+
+	case PERF_EVENT_IOC_REFRESH:
+		return perf_event_refresh(event, arg);
+
+	case PERF_EVENT_IOC_PERIOD:
+		return perf_event_period(event, (u64 __user *)arg);
+
+	case PERF_EVENT_IOC_SET_OUTPUT:
+		return perf_event_set_output(event, arg);
+
+	default:
+		return -ENOTTY;
+	}
+
+	if (flags & PERF_IOC_FLAG_GROUP)
+		perf_event_for_each(event, func);
+	else
+		perf_event_for_each_child(event, func);
+
+	return 0;
+}
+
+int perf_event_task_enable(void)
+{
+	struct perf_event *event;
+
+	mutex_lock(&current->perf_event_mutex);
+	list_for_each_entry(event, &current->perf_event_list, owner_entry)
+		perf_event_for_each_child(event, perf_event_enable);
+	mutex_unlock(&current->perf_event_mutex);
+
+	return 0;
+}
+
+int perf_event_task_disable(void)
+{
+	struct perf_event *event;
+
+	mutex_lock(&current->perf_event_mutex);
+	list_for_each_entry(event, &current->perf_event_list, owner_entry)
+		perf_event_for_each_child(event, perf_event_disable);
+	mutex_unlock(&current->perf_event_mutex);
+
+	return 0;
+}
+
+#ifndef PERF_EVENT_INDEX_OFFSET
+# define PERF_EVENT_INDEX_OFFSET 0
+#endif
+
+static int perf_event_index(struct perf_event *event)
+{
+	if (event->state != PERF_EVENT_STATE_ACTIVE)
+		return 0;
+
+	return event->hw.idx + 1 - PERF_EVENT_INDEX_OFFSET;
+}
+
+/*
+ * Callers need to ensure there can be no nesting of this function, otherwise
+ * the seqlock logic goes bad. We can not serialize this because the arch
+ * code calls this from NMI context.
+ */
+void perf_event_update_userpage(struct perf_event *event)
+{
+	struct perf_event_mmap_page *userpg;
+	struct perf_mmap_data *data;
+
+	rcu_read_lock();
+	data = rcu_dereference(event->data);
+	if (!data)
+		goto unlock;
+
+	userpg = data->user_page;
+
+	/*
+	 * Disable preemption so as to not let the corresponding user-space
+	 * spin too long if we get preempted.
+	 */
+	preempt_disable();
+	++userpg->lock;
+	barrier();
+	userpg->index = perf_event_index(event);
+	userpg->offset = atomic64_read(&event->count);
+	if (event->state == PERF_EVENT_STATE_ACTIVE)
+		userpg->offset -= atomic64_read(&event->hw.prev_count);
+
+	userpg->time_enabled = event->total_time_enabled +
+			atomic64_read(&event->child_total_time_enabled);
+
+	userpg->time_running = event->total_time_running +
+			atomic64_read(&event->child_total_time_running);
+
+	barrier();
+	++userpg->lock;
+	preempt_enable();
+unlock:
+	rcu_read_unlock();
+}
+
+static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+	struct perf_event *event = vma->vm_file->private_data;
+	struct perf_mmap_data *data;
+	int ret = VM_FAULT_SIGBUS;
+
+	if (vmf->flags & FAULT_FLAG_MKWRITE) {
+		if (vmf->pgoff == 0)
+			ret = 0;
+		return ret;
+	}
+
+	rcu_read_lock();
+	data = rcu_dereference(event->data);
+	if (!data)
+		goto unlock;
+
+	if (vmf->pgoff == 0) {
+		vmf->page = virt_to_page(data->user_page);
+	} else {
+		int nr = vmf->pgoff - 1;
+
+		if ((unsigned)nr > data->nr_pages)
+			goto unlock;
+
+		if (vmf->flags & FAULT_FLAG_WRITE)
+			goto unlock;
+
+		vmf->page = virt_to_page(data->data_pages[nr]);
+	}
+
+	get_page(vmf->page);
+	vmf->page->mapping = vma->vm_file->f_mapping;
+	vmf->page->index   = vmf->pgoff;
+
+	ret = 0;
+unlock:
+	rcu_read_unlock();
+
+	return ret;
+}
+
+static int perf_mmap_data_alloc(struct perf_event *event, int nr_pages)
+{
+	struct perf_mmap_data *data;
+	unsigned long size;
+	int i;
+
+	WARN_ON(atomic_read(&event->mmap_count));
+
+	size = sizeof(struct perf_mmap_data);
+	size += nr_pages * sizeof(void *);
+
+	data = kzalloc(size, GFP_KERNEL);
+	if (!data)
+		goto fail;
+
+	data->user_page = (void *)get_zeroed_page(GFP_KERNEL);
+	if (!data->user_page)
+		goto fail_user_page;
+
+	for (i = 0; i < nr_pages; i++) {
+		data->data_pages[i] = (void *)get_zeroed_page(GFP_KERNEL);
+		if (!data->data_pages[i])
+			goto fail_data_pages;
+	}
+
+	data->nr_pages = nr_pages;
+	atomic_set(&data->lock, -1);
+
+	if (event->attr.watermark) {
+		data->watermark = min_t(long, PAGE_SIZE * nr_pages,
+				      event->attr.wakeup_watermark);
+	}
+	if (!data->watermark)
+		data->watermark = max(PAGE_SIZE, PAGE_SIZE * nr_pages / 4);
+
+	rcu_assign_pointer(event->data, data);
+
+	return 0;
+
+fail_data_pages:
+	for (i--; i >= 0; i--)
+		free_page((unsigned long)data->data_pages[i]);
+
+	free_page((unsigned long)data->user_page);
+
+fail_user_page:
+	kfree(data);
+
+fail:
+	return -ENOMEM;
+}
+
+static void perf_mmap_free_page(unsigned long addr)
+{
+	struct page *page = virt_to_page((void *)addr);
+
+	page->mapping = NULL;
+	__free_page(page);
+}
+
+static void __perf_mmap_data_free(struct rcu_head *rcu_head)
+{
+	struct perf_mmap_data *data;
+	int i;
+
+	data = container_of(rcu_head, struct perf_mmap_data, rcu_head);
+
+	perf_mmap_free_page((unsigned long)data->user_page);
+	for (i = 0; i < data->nr_pages; i++)
+		perf_mmap_free_page((unsigned long)data->data_pages[i]);
+
+	kfree(data);
+}
+
+static void perf_mmap_data_free(struct perf_event *event)
+{
+	struct perf_mmap_data *data = event->data;
+
+	WARN_ON(atomic_read(&event->mmap_count));
+
+	rcu_assign_pointer(event->data, NULL);
+	call_rcu(&data->rcu_head, __perf_mmap_data_free);
+}
+
+static void perf_mmap_open(struct vm_area_struct *vma)
+{
+	struct perf_event *event = vma->vm_file->private_data;
+
+	atomic_inc(&event->mmap_count);
+}
+
+static void perf_mmap_close(struct vm_area_struct *vma)
+{
+	struct perf_event *event = vma->vm_file->private_data;
+
+	WARN_ON_ONCE(event->ctx->parent_ctx);
+	if (atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) {
+		struct user_struct *user = current_user();
+
+		atomic_long_sub(event->data->nr_pages + 1, &user->locked_vm);
+		vma->vm_mm->locked_vm -= event->data->nr_locked;
+		perf_mmap_data_free(event);
+		mutex_unlock(&event->mmap_mutex);
+	}
+}
+
+static struct vm_operations_struct perf_mmap_vmops = {
+	.open		= perf_mmap_open,
+	.close		= perf_mmap_close,
+	.fault		= perf_mmap_fault,
+	.page_mkwrite	= perf_mmap_fault,
+};
+
+static int perf_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct perf_event *event = file->private_data;
+	unsigned long user_locked, user_lock_limit;
+	struct user_struct *user = current_user();
+	unsigned long locked, lock_limit;
+	unsigned long vma_size;
+	unsigned long nr_pages;
+	long user_extra, extra;
+	int ret = 0;
+
+	if (!(vma->vm_flags & VM_SHARED))
+		return -EINVAL;
+
+	vma_size = vma->vm_end - vma->vm_start;
+	nr_pages = (vma_size / PAGE_SIZE) - 1;
+
+	/*
+	 * If we have data pages ensure they're a power-of-two number, so we
+	 * can do bitmasks instead of modulo.
+	 */
+	if (nr_pages != 0 && !is_power_of_2(nr_pages))
+		return -EINVAL;
+
+	if (vma_size != PAGE_SIZE * (1 + nr_pages))
+		return -EINVAL;
+
+	if (vma->vm_pgoff != 0)
+		return -EINVAL;
+
+	WARN_ON_ONCE(event->ctx->parent_ctx);
+	mutex_lock(&event->mmap_mutex);
+	if (event->output) {
+		ret = -EINVAL;
+		goto unlock;
+	}
+
+	if (atomic_inc_not_zero(&event->mmap_count)) {
+		if (nr_pages != event->data->nr_pages)
+			ret = -EINVAL;
+		goto unlock;
+	}
+
+	user_extra = nr_pages + 1;
+	user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10);
+
+	/*
+	 * Increase the limit linearly with more CPUs:
+	 */
+	user_lock_limit *= num_online_cpus();
+
+	user_locked = atomic_long_read(&user->locked_vm) + user_extra;
+
+	extra = 0;
+	if (user_locked > user_lock_limit)
+		extra = user_locked - user_lock_limit;
+
+	lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
+	lock_limit >>= PAGE_SHIFT;
+	locked = vma->vm_mm->locked_vm + extra;
+
+	if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() &&
+		!capable(CAP_IPC_LOCK)) {
+		ret = -EPERM;
+		goto unlock;
+	}
+
+	WARN_ON(event->data);
+	ret = perf_mmap_data_alloc(event, nr_pages);
+	if (ret)
+		goto unlock;
+
+	atomic_set(&event->mmap_count, 1);
+	atomic_long_add(user_extra, &user->locked_vm);
+	vma->vm_mm->locked_vm += extra;
+	event->data->nr_locked = extra;
+	if (vma->vm_flags & VM_WRITE)
+		event->data->writable = 1;
+
+unlock:
+	mutex_unlock(&event->mmap_mutex);
+
+	vma->vm_flags |= VM_RESERVED;
+	vma->vm_ops = &perf_mmap_vmops;
+
+	return ret;
+}
+
+static int perf_fasync(int fd, struct file *filp, int on)
+{
+	struct inode *inode = filp->f_path.dentry->d_inode;
+	struct perf_event *event = filp->private_data;
+	int retval;
+
+	mutex_lock(&inode->i_mutex);
+	retval = fasync_helper(fd, filp, on, &event->fasync);
+	mutex_unlock(&inode->i_mutex);
+
+	if (retval < 0)
+		return retval;
+
+	return 0;
+}
+
+static const struct file_operations perf_fops = {
+	.release		= perf_release,
+	.read			= perf_read,
+	.poll			= perf_poll,
+	.unlocked_ioctl		= perf_ioctl,
+	.compat_ioctl		= perf_ioctl,
+	.mmap			= perf_mmap,
+	.fasync			= perf_fasync,
+};
+
+/*
+ * Perf event wakeup
+ *
+ * If there's data, ensure we set the poll() state and publish everything
+ * to user-space before waking everybody up.
+ */
+
+void perf_event_wakeup(struct perf_event *event)
+{
+	wake_up_all(&event->waitq);
+
+	if (event->pending_kill) {
+		kill_fasync(&event->fasync, SIGIO, event->pending_kill);
+		event->pending_kill = 0;
+	}
+}
+
+/*
+ * Pending wakeups
+ *
+ * Handle the case where we need to wakeup up from NMI (or rq->lock) context.
+ *
+ * The NMI bit means we cannot possibly take locks. Therefore, maintain a
+ * single linked list and use cmpxchg() to add entries lockless.
+ */
+
+static void perf_pending_event(struct perf_pending_entry *entry)
+{
+	struct perf_event *event = container_of(entry,
+			struct perf_event, pending);
+
+	if (event->pending_disable) {
+		event->pending_disable = 0;
+		__perf_event_disable(event);
+	}
+
+	if (event->pending_wakeup) {
+		event->pending_wakeup = 0;
+		perf_event_wakeup(event);
+	}
+}
+
+#define PENDING_TAIL ((struct perf_pending_entry *)-1UL)
+
+static DEFINE_PER_CPU(struct perf_pending_entry *, perf_pending_head) = {
+	PENDING_TAIL,
+};
+
+static void perf_pending_queue(struct perf_pending_entry *entry,
+			       void (*func)(struct perf_pending_entry *))
+{
+	struct perf_pending_entry **head;
+
+	if (cmpxchg(&entry->next, NULL, PENDING_TAIL) != NULL)
+		return;
+
+	entry->func = func;
+
+	head = &get_cpu_var(perf_pending_head);
+
+	do {
+		entry->next = *head;
+	} while (cmpxchg(head, entry->next, entry) != entry->next);
+
+	set_perf_event_pending();
+
+	put_cpu_var(perf_pending_head);
+}
+
+static int __perf_pending_run(void)
+{
+	struct perf_pending_entry *list;
+	int nr = 0;
+
+	list = xchg(&__get_cpu_var(perf_pending_head), PENDING_TAIL);
+	while (list != PENDING_TAIL) {
+		void (*func)(struct perf_pending_entry *);
+		struct perf_pending_entry *entry = list;
+
+		list = list->next;
+
+		func = entry->func;
+		entry->next = NULL;
+		/*
+		 * Ensure we observe the unqueue before we issue the wakeup,
+		 * so that we won't be waiting forever.
+		 * -- see perf_not_pending().
+		 */
+		smp_wmb();
+
+		func(entry);
+		nr++;
+	}
+
+	return nr;
+}
+
+static inline int perf_not_pending(struct perf_event *event)
+{
+	/*
+	 * If we flush on whatever cpu we run, there is a chance we don't
+	 * need to wait.
+	 */
+	get_cpu();
+	__perf_pending_run();
+	put_cpu();
+
+	/*
+	 * Ensure we see the proper queue state before going to sleep
+	 * so that we do not miss the wakeup. -- see perf_pending_handle()
+	 */
+	smp_rmb();
+	return event->pending.next == NULL;
+}
+
+static void perf_pending_sync(struct perf_event *event)
+{
+	wait_event(event->waitq, perf_not_pending(event));
+}
+
+void perf_event_do_pending(void)
+{
+	__perf_pending_run();
+}
+
+/*
+ * Callchain support -- arch specific
+ */
+
+__weak struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
+{
+	return NULL;
+}
+
+/*
+ * Output
+ */
+static bool perf_output_space(struct perf_mmap_data *data, unsigned long tail,
+			      unsigned long offset, unsigned long head)
+{
+	unsigned long mask;
+
+	if (!data->writable)
+		return true;
+
+	mask = (data->nr_pages << PAGE_SHIFT) - 1;
+
+	offset = (offset - tail) & mask;
+	head   = (head   - tail) & mask;
+
+	if ((int)(head - offset) < 0)
+		return false;
+
+	return true;
+}
+
+static void perf_output_wakeup(struct perf_output_handle *handle)
+{
+	atomic_set(&handle->data->poll, POLL_IN);
+
+	if (handle->nmi) {
+		handle->event->pending_wakeup = 1;
+		perf_pending_queue(&handle->event->pending,
+				   perf_pending_event);
+	} else
+		perf_event_wakeup(handle->event);
+}
+
+/*
+ * Curious locking construct.
+ *
+ * We need to ensure a later event_id doesn't publish a head when a former
+ * event_id isn't done writing. However since we need to deal with NMIs we
+ * cannot fully serialize things.
+ *
+ * What we do is serialize between CPUs so we only have to deal with NMI
+ * nesting on a single CPU.
+ *
+ * We only publish the head (and generate a wakeup) when the outer-most
+ * event_id completes.
+ */
+static void perf_output_lock(struct perf_output_handle *handle)
+{
+	struct perf_mmap_data *data = handle->data;
+	int cpu;
+
+	handle->locked = 0;
+
+	local_irq_save(handle->flags);
+	cpu = smp_processor_id();
+
+	if (in_nmi() && atomic_read(&data->lock) == cpu)
+		return;
+
+	while (atomic_cmpxchg(&data->lock, -1, cpu) != -1)
+		cpu_relax();
+
+	handle->locked = 1;
+}
+
+static void perf_output_unlock(struct perf_output_handle *handle)
+{
+	struct perf_mmap_data *data = handle->data;
+	unsigned long head;
+	int cpu;
+
+	data->done_head = data->head;
+
+	if (!handle->locked)
+		goto out;
+
+again:
+	/*
+	 * The xchg implies a full barrier that ensures all writes are done
+	 * before we publish the new head, matched by a rmb() in userspace when
+	 * reading this position.
+	 */
+	while ((head = atomic_long_xchg(&data->done_head, 0)))
+		data->user_page->data_head = head;
+
+	/*
+	 * NMI can happen here, which means we can miss a done_head update.
+	 */
+
+	cpu = atomic_xchg(&data->lock, -1);
+	WARN_ON_ONCE(cpu != smp_processor_id());
+
+	/*
+	 * Therefore we have to validate we did not indeed do so.
+	 */
+	if (unlikely(atomic_long_read(&data->done_head))) {
+		/*
+		 * Since we had it locked, we can lock it again.
+		 */
+		while (atomic_cmpxchg(&data->lock, -1, cpu) != -1)
+			cpu_relax();
+
+		goto again;
+	}
+
+	if (atomic_xchg(&data->wakeup, 0))
+		perf_output_wakeup(handle);
+out:
+	local_irq_restore(handle->flags);
+}
+
+void perf_output_copy(struct perf_output_handle *handle,
+		      const void *buf, unsigned int len)
+{
+	unsigned int pages_mask;
+	unsigned int offset;
+	unsigned int size;
+	void **pages;
+
+	offset		= handle->offset;
+	pages_mask	= handle->data->nr_pages - 1;
+	pages		= handle->data->data_pages;
+
+	do {
+		unsigned int page_offset;
+		int nr;
+
+		nr	    = (offset >> PAGE_SHIFT) & pages_mask;
+		page_offset = offset & (PAGE_SIZE - 1);
+		size	    = min_t(unsigned int, PAGE_SIZE - page_offset, len);
+
+		memcpy(pages[nr] + page_offset, buf, size);
+
+		len	    -= size;
+		buf	    += size;
+		offset	    += size;
+	} while (len);
+
+	handle->offset = offset;
+
+	/*
+	 * Check we didn't copy past our reservation window, taking the
+	 * possible unsigned int wrap into account.
+	 */
+	WARN_ON_ONCE(((long)(handle->head - handle->offset)) < 0);
+}
+
+int perf_output_begin(struct perf_output_handle *handle,
+		      struct perf_event *event, unsigned int size,
+		      int nmi, int sample)
+{
+	struct perf_event *output_event;
+	struct perf_mmap_data *data;
+	unsigned long tail, offset, head;
+	int have_lost;
+	struct {
+		struct perf_event_header header;
+		u64			 id;
+		u64			 lost;
+	} lost_event;
+
+	rcu_read_lock();
+	/*
+	 * For inherited events we send all the output towards the parent.
+	 */
+	if (event->parent)
+		event = event->parent;
+
+	output_event = rcu_dereference(event->output);
+	if (output_event)
+		event = output_event;
+
+	data = rcu_dereference(event->data);
+	if (!data)
+		goto out;
+
+	handle->data	= data;
+	handle->event	= event;
+	handle->nmi	= nmi;
+	handle->sample	= sample;
+
+	if (!data->nr_pages)
+		goto fail;
+
+	have_lost = atomic_read(&data->lost);
+	if (have_lost)
+		size += sizeof(lost_event);
+
+	perf_output_lock(handle);
+
+	do {
+		/*
+		 * Userspace could choose to issue a mb() before updating the
+		 * tail pointer. So that all reads will be completed before the
+		 * write is issued.
+		 */
+		tail = ACCESS_ONCE(data->user_page->data_tail);
+		smp_rmb();
+		offset = head = atomic_long_read(&data->head);
+		head += size;
+		if (unlikely(!perf_output_space(data, tail, offset, head)))
+			goto fail;
+	} while (atomic_long_cmpxchg(&data->head, offset, head) != offset);
+
+	handle->offset	= offset;
+	handle->head	= head;
+
+	if (head - tail > data->watermark)
+		atomic_set(&data->wakeup, 1);
+
+	if (have_lost) {
+		lost_event.header.type = PERF_RECORD_LOST;
+		lost_event.header.misc = 0;
+		lost_event.header.size = sizeof(lost_event);
+		lost_event.id          = event->id;
+		lost_event.lost        = atomic_xchg(&data->lost, 0);
+
+		perf_output_put(handle, lost_event);
+	}
+
+	return 0;
+
+fail:
+	atomic_inc(&data->lost);
+	perf_output_unlock(handle);
+out:
+	rcu_read_unlock();
+
+	return -ENOSPC;
+}
+
+void perf_output_end(struct perf_output_handle *handle)
+{
+	struct perf_event *event = handle->event;
+	struct perf_mmap_data *data = handle->data;
+
+	int wakeup_events = event->attr.wakeup_events;
+
+	if (handle->sample && wakeup_events) {
+		int events = atomic_inc_return(&data->events);
+		if (events >= wakeup_events) {
+			atomic_sub(wakeup_events, &data->events);
+			atomic_set(&data->wakeup, 1);
+		}
+	}
+
+	perf_output_unlock(handle);
+	rcu_read_unlock();
+}
+
+static u32 perf_event_pid(struct perf_event *event, struct task_struct *p)
+{
+	/*
+	 * only top level events have the pid namespace they were created in
+	 */
+	if (event->parent)
+		event = event->parent;
+
+	return task_tgid_nr_ns(p, event->ns);
+}
+
+static u32 perf_event_tid(struct perf_event *event, struct task_struct *p)
+{
+	/*
+	 * only top level events have the pid namespace they were created in
+	 */
+	if (event->parent)
+		event = event->parent;
+
+	return task_pid_nr_ns(p, event->ns);
+}
+
+static void perf_output_read_one(struct perf_output_handle *handle,
+				 struct perf_event *event)
+{
+	u64 read_format = event->attr.read_format;
+	u64 values[4];
+	int n = 0;
+
+	values[n++] = atomic64_read(&event->count);
+	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
+		values[n++] = event->total_time_enabled +
+			atomic64_read(&event->child_total_time_enabled);
+	}
+	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
+		values[n++] = event->total_time_running +
+			atomic64_read(&event->child_total_time_running);
+	}
+	if (read_format & PERF_FORMAT_ID)
+		values[n++] = primary_event_id(event);
+
+	perf_output_copy(handle, values, n * sizeof(u64));
+}
+
+/*
+ * XXX PERF_FORMAT_GROUP vs inherited events seems difficult.
+ */
+static void perf_output_read_group(struct perf_output_handle *handle,
+			    struct perf_event *event)
+{
+	struct perf_event *leader = event->group_leader, *sub;
+	u64 read_format = event->attr.read_format;
+	u64 values[5];
+	int n = 0;
+
+	values[n++] = 1 + leader->nr_siblings;
+
+	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+		values[n++] = leader->total_time_enabled;
+
+	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+		values[n++] = leader->total_time_running;
+
+	if (leader != event)
+		leader->pmu->read(leader);
+
+	values[n++] = atomic64_read(&leader->count);
+	if (read_format & PERF_FORMAT_ID)
+		values[n++] = primary_event_id(leader);
+
+	perf_output_copy(handle, values, n * sizeof(u64));
+
+	list_for_each_entry(sub, &leader->sibling_list, group_entry) {
+		n = 0;
+
+		if (sub != event)
+			sub->pmu->read(sub);
+
+		values[n++] = atomic64_read(&sub->count);
+		if (read_format & PERF_FORMAT_ID)
+			values[n++] = primary_event_id(sub);
+
+		perf_output_copy(handle, values, n * sizeof(u64));
+	}
+}
+
+static void perf_output_read(struct perf_output_handle *handle,
+			     struct perf_event *event)
+{
+	if (event->attr.read_format & PERF_FORMAT_GROUP)
+		perf_output_read_group(handle, event);
+	else
+		perf_output_read_one(handle, event);
+}
+
+void perf_output_sample(struct perf_output_handle *handle,
+			struct perf_event_header *header,
+			struct perf_sample_data *data,
+			struct perf_event *event)
+{
+	u64 sample_type = data->type;
+
+	perf_output_put(handle, *header);
+
+	if (sample_type & PERF_SAMPLE_IP)
+		perf_output_put(handle, data->ip);
+
+	if (sample_type & PERF_SAMPLE_TID)
+		perf_output_put(handle, data->tid_entry);
+
+	if (sample_type & PERF_SAMPLE_TIME)
+		perf_output_put(handle, data->time);
+
+	if (sample_type & PERF_SAMPLE_ADDR)
+		perf_output_put(handle, data->addr);
+
+	if (sample_type & PERF_SAMPLE_ID)
+		perf_output_put(handle, data->id);
+
+	if (sample_type & PERF_SAMPLE_STREAM_ID)
+		perf_output_put(handle, data->stream_id);
+
+	if (sample_type & PERF_SAMPLE_CPU)
+		perf_output_put(handle, data->cpu_entry);
+
+	if (sample_type & PERF_SAMPLE_PERIOD)
+		perf_output_put(handle, data->period);
+
+	if (sample_type & PERF_SAMPLE_READ)
+		perf_output_read(handle, event);
+
+	if (sample_type & PERF_SAMPLE_CALLCHAIN) {
+		if (data->callchain) {
+			int size = 1;
+
+			if (data->callchain)
+				size += data->callchain->nr;
+
+			size *= sizeof(u64);
+
+			perf_output_copy(handle, data->callchain, size);
+		} else {
+			u64 nr = 0;
+			perf_output_put(handle, nr);
+		}
+	}
+
+	if (sample_type & PERF_SAMPLE_RAW) {
+		if (data->raw) {
+			perf_output_put(handle, data->raw->size);
+			perf_output_copy(handle, data->raw->data,
+					 data->raw->size);
+		} else {
+			struct {
+				u32	size;
+				u32	data;
+			} raw = {
+				.size = sizeof(u32),
+				.data = 0,
+			};
+			perf_output_put(handle, raw);
+		}
+	}
+}
+
+void perf_prepare_sample(struct perf_event_header *header,
+			 struct perf_sample_data *data,
+			 struct perf_event *event,
+			 struct pt_regs *regs)
+{
+	u64 sample_type = event->attr.sample_type;
+
+	data->type = sample_type;
+
+	header->type = PERF_RECORD_SAMPLE;
+	header->size = sizeof(*header);
+
+	header->misc = 0;
+	header->misc |= perf_misc_flags(regs);
+
+	if (sample_type & PERF_SAMPLE_IP) {
+		data->ip = perf_instruction_pointer(regs);
+
+		header->size += sizeof(data->ip);
+	}
+
+	if (sample_type & PERF_SAMPLE_TID) {
+		/* namespace issues */
+		data->tid_entry.pid = perf_event_pid(event, current);
+		data->tid_entry.tid = perf_event_tid(event, current);
+
+		header->size += sizeof(data->tid_entry);
+	}
+
+	if (sample_type & PERF_SAMPLE_TIME) {
+		data->time = perf_clock();
+
+		header->size += sizeof(data->time);
+	}
+
+	if (sample_type & PERF_SAMPLE_ADDR)
+		header->size += sizeof(data->addr);
+
+	if (sample_type & PERF_SAMPLE_ID) {
+		data->id = primary_event_id(event);
+
+		header->size += sizeof(data->id);
+	}
+
+	if (sample_type & PERF_SAMPLE_STREAM_ID) {
+		data->stream_id = event->id;
+
+		header->size += sizeof(data->stream_id);
+	}
+
+	if (sample_type & PERF_SAMPLE_CPU) {
+		data->cpu_entry.cpu		= raw_smp_processor_id();
+		data->cpu_entry.reserved	= 0;
+
+		header->size += sizeof(data->cpu_entry);
+	}
+
+	if (sample_type & PERF_SAMPLE_PERIOD)
+		header->size += sizeof(data->period);
+
+	if (sample_type & PERF_SAMPLE_READ)
+		header->size += perf_event_read_size(event);
+
+	if (sample_type & PERF_SAMPLE_CALLCHAIN) {
+		int size = 1;
+
+		data->callchain = perf_callchain(regs);
+
+		if (data->callchain)
+			size += data->callchain->nr;
+
+		header->size += size * sizeof(u64);
+	}
+
+	if (sample_type & PERF_SAMPLE_RAW) {
+		int size = sizeof(u32);
+
+		if (data->raw)
+			size += data->raw->size;
+		else
+			size += sizeof(u32);
+
+		WARN_ON_ONCE(size & (sizeof(u64)-1));
+		header->size += size;
+	}
+}
+
+static void perf_event_output(struct perf_event *event, int nmi,
+				struct perf_sample_data *data,
+				struct pt_regs *regs)
+{
+	struct perf_output_handle handle;
+	struct perf_event_header header;
+
+	perf_prepare_sample(&header, data, event, regs);
+
+	if (perf_output_begin(&handle, event, header.size, nmi, 1))
+		return;
+
+	perf_output_sample(&handle, &header, data, event);
+
+	perf_output_end(&handle);
+}
+
+/*
+ * read event_id
+ */
+
+struct perf_read_event {
+	struct perf_event_header	header;
+
+	u32				pid;
+	u32				tid;
+};
+
+static void
+perf_event_read_event(struct perf_event *event,
+			struct task_struct *task)
+{
+	struct perf_output_handle handle;
+	struct perf_read_event read_event = {
+		.header = {
+			.type = PERF_RECORD_READ,
+			.misc = 0,
+			.size = sizeof(read_event) + perf_event_read_size(event),
+		},
+		.pid = perf_event_pid(event, task),
+		.tid = perf_event_tid(event, task),
+	};
+	int ret;
+
+	ret = perf_output_begin(&handle, event, read_event.header.size, 0, 0);
+	if (ret)
+		return;
+
+	perf_output_put(&handle, read_event);
+	perf_output_read(&handle, event);
+
+	perf_output_end(&handle);
+}
+
+/*
+ * task tracking -- fork/exit
+ *
+ * enabled by: attr.comm | attr.mmap | attr.task
+ */
+
+struct perf_task_event {
+	struct task_struct		*task;
+	struct perf_event_context	*task_ctx;
+
+	struct {
+		struct perf_event_header	header;
+
+		u32				pid;
+		u32				ppid;
+		u32				tid;
+		u32				ptid;
+		u64				time;
+	} event_id;
+};
+
+static void perf_event_task_output(struct perf_event *event,
+				     struct perf_task_event *task_event)
+{
+	struct perf_output_handle handle;
+	int size;
+	struct task_struct *task = task_event->task;
+	int ret;
+
+	size  = task_event->event_id.header.size;
+	ret = perf_output_begin(&handle, event, size, 0, 0);
+
+	if (ret)
+		return;
+
+	task_event->event_id.pid = perf_event_pid(event, task);
+	task_event->event_id.ppid = perf_event_pid(event, current);
+
+	task_event->event_id.tid = perf_event_tid(event, task);
+	task_event->event_id.ptid = perf_event_tid(event, current);
+
+	task_event->event_id.time = perf_clock();
+
+	perf_output_put(&handle, task_event->event_id);
+
+	perf_output_end(&handle);
+}
+
+static int perf_event_task_match(struct perf_event *event)
+{
+	if (event->attr.comm || event->attr.mmap || event->attr.task)
+		return 1;
+
+	return 0;
+}
+
+static void perf_event_task_ctx(struct perf_event_context *ctx,
+				  struct perf_task_event *task_event)
+{
+	struct perf_event *event;
+
+	if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
+		return;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
+		if (perf_event_task_match(event))
+			perf_event_task_output(event, task_event);
+	}
+	rcu_read_unlock();
+}
+
+static void perf_event_task_event(struct perf_task_event *task_event)
+{
+	struct perf_cpu_context *cpuctx;
+	struct perf_event_context *ctx = task_event->task_ctx;
+
+	cpuctx = &get_cpu_var(perf_cpu_context);
+	perf_event_task_ctx(&cpuctx->ctx, task_event);
+	put_cpu_var(perf_cpu_context);
+
+	rcu_read_lock();
+	if (!ctx)
+		ctx = rcu_dereference(task_event->task->perf_event_ctxp);
+	if (ctx)
+		perf_event_task_ctx(ctx, task_event);
+	rcu_read_unlock();
+}
+
+static void perf_event_task(struct task_struct *task,
+			      struct perf_event_context *task_ctx,
+			      int new)
+{
+	struct perf_task_event task_event;
+
+	if (!atomic_read(&nr_comm_events) &&
+	    !atomic_read(&nr_mmap_events) &&
+	    !atomic_read(&nr_task_events))
+		return;
+
+	task_event = (struct perf_task_event){
+		.task	  = task,
+		.task_ctx = task_ctx,
+		.event_id    = {
+			.header = {
+				.type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT,
+				.misc = 0,
+				.size = sizeof(task_event.event_id),
+			},
+			/* .pid  */
+			/* .ppid */
+			/* .tid  */
+			/* .ptid */
+		},
+	};
+
+	perf_event_task_event(&task_event);
+}
+
+void perf_event_fork(struct task_struct *task)
+{
+	perf_event_task(task, NULL, 1);
+}
+
+/*
+ * comm tracking
+ */
+
+struct perf_comm_event {
+	struct task_struct	*task;
+	char			*comm;
+	int			comm_size;
+
+	struct {
+		struct perf_event_header	header;
+
+		u32				pid;
+		u32				tid;
+	} event_id;
+};
+
+static void perf_event_comm_output(struct perf_event *event,
+				     struct perf_comm_event *comm_event)
+{
+	struct perf_output_handle handle;
+	int size = comm_event->event_id.header.size;
+	int ret = perf_output_begin(&handle, event, size, 0, 0);
+
+	if (ret)
+		return;
+
+	comm_event->event_id.pid = perf_event_pid(event, comm_event->task);
+	comm_event->event_id.tid = perf_event_tid(event, comm_event->task);
+
+	perf_output_put(&handle, comm_event->event_id);
+	perf_output_copy(&handle, comm_event->comm,
+				   comm_event->comm_size);
+	perf_output_end(&handle);
+}
+
+static int perf_event_comm_match(struct perf_event *event)
+{
+	if (event->attr.comm)
+		return 1;
+
+	return 0;
+}
+
+static void perf_event_comm_ctx(struct perf_event_context *ctx,
+				  struct perf_comm_event *comm_event)
+{
+	struct perf_event *event;
+
+	if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
+		return;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
+		if (perf_event_comm_match(event))
+			perf_event_comm_output(event, comm_event);
+	}
+	rcu_read_unlock();
+}
+
+static void perf_event_comm_event(struct perf_comm_event *comm_event)
+{
+	struct perf_cpu_context *cpuctx;
+	struct perf_event_context *ctx;
+	unsigned int size;
+	char comm[TASK_COMM_LEN];
+
+	memset(comm, 0, sizeof(comm));
+	strncpy(comm, comm_event->task->comm, sizeof(comm));
+	size = ALIGN(strlen(comm)+1, sizeof(u64));
+
+	comm_event->comm = comm;
+	comm_event->comm_size = size;
+
+	comm_event->event_id.header.size = sizeof(comm_event->event_id) + size;
+
+	cpuctx = &get_cpu_var(perf_cpu_context);
+	perf_event_comm_ctx(&cpuctx->ctx, comm_event);
+	put_cpu_var(perf_cpu_context);
+
+	rcu_read_lock();
+	/*
+	 * doesn't really matter which of the child contexts the
+	 * events ends up in.
+	 */
+	ctx = rcu_dereference(current->perf_event_ctxp);
+	if (ctx)
+		perf_event_comm_ctx(ctx, comm_event);
+	rcu_read_unlock();
+}
+
+void perf_event_comm(struct task_struct *task)
+{
+	struct perf_comm_event comm_event;
+
+	if (task->perf_event_ctxp)
+		perf_event_enable_on_exec(task);
+
+	if (!atomic_read(&nr_comm_events))
+		return;
+
+	comm_event = (struct perf_comm_event){
+		.task	= task,
+		/* .comm      */
+		/* .comm_size */
+		.event_id  = {
+			.header = {
+				.type = PERF_RECORD_COMM,
+				.misc = 0,
+				/* .size */
+			},
+			/* .pid */
+			/* .tid */
+		},
+	};
+
+	perf_event_comm_event(&comm_event);
+}
+
+/*
+ * mmap tracking
+ */
+
+struct perf_mmap_event {
+	struct vm_area_struct	*vma;
+
+	const char		*file_name;
+	int			file_size;
+
+	struct {
+		struct perf_event_header	header;
+
+		u32				pid;
+		u32				tid;
+		u64				start;
+		u64				len;
+		u64				pgoff;
+	} event_id;
+};
+
+static void perf_event_mmap_output(struct perf_event *event,
+				     struct perf_mmap_event *mmap_event)
+{
+	struct perf_output_handle handle;
+	int size = mmap_event->event_id.header.size;
+	int ret = perf_output_begin(&handle, event, size, 0, 0);
+
+	if (ret)
+		return;
+
+	mmap_event->event_id.pid = perf_event_pid(event, current);
+	mmap_event->event_id.tid = perf_event_tid(event, current);
+
+	perf_output_put(&handle, mmap_event->event_id);
+	perf_output_copy(&handle, mmap_event->file_name,
+				   mmap_event->file_size);
+	perf_output_end(&handle);
+}
+
+static int perf_event_mmap_match(struct perf_event *event,
+				   struct perf_mmap_event *mmap_event)
+{
+	if (event->attr.mmap)
+		return 1;
+
+	return 0;
+}
+
+static void perf_event_mmap_ctx(struct perf_event_context *ctx,
+				  struct perf_mmap_event *mmap_event)
+{
+	struct perf_event *event;
+
+	if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
+		return;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
+		if (perf_event_mmap_match(event, mmap_event))
+			perf_event_mmap_output(event, mmap_event);
+	}
+	rcu_read_unlock();
+}
+
+static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
+{
+	struct perf_cpu_context *cpuctx;
+	struct perf_event_context *ctx;
+	struct vm_area_struct *vma = mmap_event->vma;
+	struct file *file = vma->vm_file;
+	unsigned int size;
+	char tmp[16];
+	char *buf = NULL;
+	const char *name;
+
+	memset(tmp, 0, sizeof(tmp));
+
+	if (file) {
+		/*
+		 * d_path works from the end of the buffer backwards, so we
+		 * need to add enough zero bytes after the string to handle
+		 * the 64bit alignment we do later.
+		 */
+		buf = kzalloc(PATH_MAX + sizeof(u64), GFP_KERNEL);
+		if (!buf) {
+			name = strncpy(tmp, "//enomem", sizeof(tmp));
+			goto got_name;
+		}
+		name = d_path(&file->f_path, buf, PATH_MAX);
+		if (IS_ERR(name)) {
+			name = strncpy(tmp, "//toolong", sizeof(tmp));
+			goto got_name;
+		}
+	} else {
+		if (arch_vma_name(mmap_event->vma)) {
+			name = strncpy(tmp, arch_vma_name(mmap_event->vma),
+				       sizeof(tmp));
+			goto got_name;
+		}
+
+		if (!vma->vm_mm) {
+			name = strncpy(tmp, "[vdso]", sizeof(tmp));
+			goto got_name;
+		}
+
+		name = strncpy(tmp, "//anon", sizeof(tmp));
+		goto got_name;
+	}
+
+got_name:
+	size = ALIGN(strlen(name)+1, sizeof(u64));
+
+	mmap_event->file_name = name;
+	mmap_event->file_size = size;
+
+	mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size;
+
+	cpuctx = &get_cpu_var(perf_cpu_context);
+	perf_event_mmap_ctx(&cpuctx->ctx, mmap_event);
+	put_cpu_var(perf_cpu_context);
+
+	rcu_read_lock();
+	/*
+	 * doesn't really matter which of the child contexts the
+	 * events ends up in.
+	 */
+	ctx = rcu_dereference(current->perf_event_ctxp);
+	if (ctx)
+		perf_event_mmap_ctx(ctx, mmap_event);
+	rcu_read_unlock();
+
+	kfree(buf);
+}
+
+void __perf_event_mmap(struct vm_area_struct *vma)
+{
+	struct perf_mmap_event mmap_event;
+
+	if (!atomic_read(&nr_mmap_events))
+		return;
+
+	mmap_event = (struct perf_mmap_event){
+		.vma	= vma,
+		/* .file_name */
+		/* .file_size */
+		.event_id  = {
+			.header = {
+				.type = PERF_RECORD_MMAP,
+				.misc = 0,
+				/* .size */
+			},
+			/* .pid */
+			/* .tid */
+			.start  = vma->vm_start,
+			.len    = vma->vm_end - vma->vm_start,
+			.pgoff  = vma->vm_pgoff,
+		},
+	};
+
+	perf_event_mmap_event(&mmap_event);
+}
+
+/*
+ * IRQ throttle logging
+ */
+
+static void perf_log_throttle(struct perf_event *event, int enable)
+{
+	struct perf_output_handle handle;
+	int ret;
+
+	struct {
+		struct perf_event_header	header;
+		u64				time;
+		u64				id;
+		u64				stream_id;
+	} throttle_event = {
+		.header = {
+			.type = PERF_RECORD_THROTTLE,
+			.misc = 0,
+			.size = sizeof(throttle_event),
+		},
+		.time		= perf_clock(),
+		.id		= primary_event_id(event),
+		.stream_id	= event->id,
+	};
+
+	if (enable)
+		throttle_event.header.type = PERF_RECORD_UNTHROTTLE;
+
+	ret = perf_output_begin(&handle, event, sizeof(throttle_event), 1, 0);
+	if (ret)
+		return;
+
+	perf_output_put(&handle, throttle_event);
+	perf_output_end(&handle);
+}
+
+/*
+ * Generic event overflow handling, sampling.
+ */
+
+static int __perf_event_overflow(struct perf_event *event, int nmi,
+				   int throttle, struct perf_sample_data *data,
+				   struct pt_regs *regs)
+{
+	int events = atomic_read(&event->event_limit);
+	struct hw_perf_event *hwc = &event->hw;
+	int ret = 0;
+
+	throttle = (throttle && event->pmu->unthrottle != NULL);
+
+	if (!throttle) {
+		hwc->interrupts++;
+	} else {
+		if (hwc->interrupts != MAX_INTERRUPTS) {
+			hwc->interrupts++;
+			if (HZ * hwc->interrupts >
+					(u64)sysctl_perf_event_sample_rate) {
+				hwc->interrupts = MAX_INTERRUPTS;
+				perf_log_throttle(event, 0);
+				ret = 1;
+			}
+		} else {
+			/*
+			 * Keep re-disabling events even though on the previous
+			 * pass we disabled it - just in case we raced with a
+			 * sched-in and the event got enabled again:
+			 */
+			ret = 1;
+		}
+	}
+
+	if (event->attr.freq) {
+		u64 now = perf_clock();
+		s64 delta = now - hwc->freq_stamp;
+
+		hwc->freq_stamp = now;
+
+		if (delta > 0 && delta < TICK_NSEC)
+			perf_adjust_period(event, NSEC_PER_SEC / (int)delta);
+	}
+
+	/*
+	 * XXX event_limit might not quite work as expected on inherited
+	 * events
+	 */
+
+	event->pending_kill = POLL_IN;
+	if (events && atomic_dec_and_test(&event->event_limit)) {
+		ret = 1;
+		event->pending_kill = POLL_HUP;
+		if (nmi) {
+			event->pending_disable = 1;
+			perf_pending_queue(&event->pending,
+					   perf_pending_event);
+		} else
+			perf_event_disable(event);
+	}
+
+	perf_event_output(event, nmi, data, regs);
+	return ret;
+}
+
+int perf_event_overflow(struct perf_event *event, int nmi,
+			  struct perf_sample_data *data,
+			  struct pt_regs *regs)
+{
+	return __perf_event_overflow(event, nmi, 1, data, regs);
+}
+
+/*
+ * Generic software event infrastructure
+ */
+
+/*
+ * We directly increment event->count and keep a second value in
+ * event->hw.period_left to count intervals. This period event
+ * is kept in the range [-sample_period, 0] so that we can use the
+ * sign as trigger.
+ */
+
+static u64 perf_swevent_set_period(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	u64 period = hwc->last_period;
+	u64 nr, offset;
+	s64 old, val;
+
+	hwc->last_period = hwc->sample_period;
+
+again:
+	old = val = atomic64_read(&hwc->period_left);
+	if (val < 0)
+		return 0;
+
+	nr = div64_u64(period + val, period);
+	offset = nr * period;
+	val -= offset;
+	if (atomic64_cmpxchg(&hwc->period_left, old, val) != old)
+		goto again;
+
+	return nr;
+}
+
+static void perf_swevent_overflow(struct perf_event *event,
+				    int nmi, struct perf_sample_data *data,
+				    struct pt_regs *regs)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	int throttle = 0;
+	u64 overflow;
+
+	data->period = event->hw.last_period;
+	overflow = perf_swevent_set_period(event);
+
+	if (hwc->interrupts == MAX_INTERRUPTS)
+		return;
+
+	for (; overflow; overflow--) {
+		if (__perf_event_overflow(event, nmi, throttle,
+					    data, regs)) {
+			/*
+			 * We inhibit the overflow from happening when
+			 * hwc->interrupts == MAX_INTERRUPTS.
+			 */
+			break;
+		}
+		throttle = 1;
+	}
+}
+
+static void perf_swevent_unthrottle(struct perf_event *event)
+{
+	/*
+	 * Nothing to do, we already reset hwc->interrupts.
+	 */
+}
+
+static void perf_swevent_add(struct perf_event *event, u64 nr,
+			       int nmi, struct perf_sample_data *data,
+			       struct pt_regs *regs)
+{
+	struct hw_perf_event *hwc = &event->hw;
+
+	atomic64_add(nr, &event->count);
+
+	if (!hwc->sample_period)
+		return;
+
+	if (!regs)
+		return;
+
+	if (!atomic64_add_negative(nr, &hwc->period_left))
+		perf_swevent_overflow(event, nmi, data, regs);
+}
+
+static int perf_swevent_is_counting(struct perf_event *event)
+{
+	/*
+	 * The event is active, we're good!
+	 */
+	if (event->state == PERF_EVENT_STATE_ACTIVE)
+		return 1;
+
+	/*
+	 * The event is off/error, not counting.
+	 */
+	if (event->state != PERF_EVENT_STATE_INACTIVE)
+		return 0;
+
+	/*
+	 * The event is inactive, if the context is active
+	 * we're part of a group that didn't make it on the 'pmu',
+	 * not counting.
+	 */
+	if (event->ctx->is_active)
+		return 0;
+
+	/*
+	 * We're inactive and the context is too, this means the
+	 * task is scheduled out, we're counting events that happen
+	 * to us, like migration events.
+	 */
+	return 1;
+}
+
+static int perf_swevent_match(struct perf_event *event,
+				enum perf_type_id type,
+				u32 event_id, struct pt_regs *regs)
+{
+	if (!perf_swevent_is_counting(event))
+		return 0;
+
+	if (event->attr.type != type)
+		return 0;
+	if (event->attr.config != event_id)
+		return 0;
+
+	if (regs) {
+		if (event->attr.exclude_user && user_mode(regs))
+			return 0;
+
+		if (event->attr.exclude_kernel && !user_mode(regs))
+			return 0;
+	}
+
+	return 1;
+}
+
+static void perf_swevent_ctx_event(struct perf_event_context *ctx,
+				     enum perf_type_id type,
+				     u32 event_id, u64 nr, int nmi,
+				     struct perf_sample_data *data,
+				     struct pt_regs *regs)
+{
+	struct perf_event *event;
+
+	if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
+		return;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
+		if (perf_swevent_match(event, type, event_id, regs))
+			perf_swevent_add(event, nr, nmi, data, regs);
+	}
+	rcu_read_unlock();
+}
+
+static int *perf_swevent_recursion_context(struct perf_cpu_context *cpuctx)
+{
+	if (in_nmi())
+		return &cpuctx->recursion[3];
+
+	if (in_irq())
+		return &cpuctx->recursion[2];
+
+	if (in_softirq())
+		return &cpuctx->recursion[1];
+
+	return &cpuctx->recursion[0];
+}
+
+static void do_perf_sw_event(enum perf_type_id type, u32 event_id,
+				    u64 nr, int nmi,
+				    struct perf_sample_data *data,
+				    struct pt_regs *regs)
+{
+	struct perf_cpu_context *cpuctx = &get_cpu_var(perf_cpu_context);
+	int *recursion = perf_swevent_recursion_context(cpuctx);
+	struct perf_event_context *ctx;
+
+	if (*recursion)
+		goto out;
+
+	(*recursion)++;
+	barrier();
+
+	perf_swevent_ctx_event(&cpuctx->ctx, type, event_id,
+				 nr, nmi, data, regs);
+	rcu_read_lock();
+	/*
+	 * doesn't really matter which of the child contexts the
+	 * events ends up in.
+	 */
+	ctx = rcu_dereference(current->perf_event_ctxp);
+	if (ctx)
+		perf_swevent_ctx_event(ctx, type, event_id, nr, nmi, data, regs);
+	rcu_read_unlock();
+
+	barrier();
+	(*recursion)--;
+
+out:
+	put_cpu_var(perf_cpu_context);
+}
+
+void __perf_sw_event(u32 event_id, u64 nr, int nmi,
+			    struct pt_regs *regs, u64 addr)
+{
+	struct perf_sample_data data = {
+		.addr = addr,
+	};
+
+	do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, nmi,
+				&data, regs);
+}
+
+static void perf_swevent_read(struct perf_event *event)
+{
+}
+
+static int perf_swevent_enable(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+
+	if (hwc->sample_period) {
+		hwc->last_period = hwc->sample_period;
+		perf_swevent_set_period(event);
+	}
+	return 0;
+}
+
+static void perf_swevent_disable(struct perf_event *event)
+{
+}
+
+static const struct pmu perf_ops_generic = {
+	.enable		= perf_swevent_enable,
+	.disable	= perf_swevent_disable,
+	.read		= perf_swevent_read,
+	.unthrottle	= perf_swevent_unthrottle,
+};
+
+/*
+ * hrtimer based swevent callback
+ */
+
+static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
+{
+	enum hrtimer_restart ret = HRTIMER_RESTART;
+	struct perf_sample_data data;
+	struct pt_regs *regs;
+	struct perf_event *event;
+	u64 period;
+
+	event	= container_of(hrtimer, struct perf_event, hw.hrtimer);
+	event->pmu->read(event);
+
+	data.addr = 0;
+	regs = get_irq_regs();
+	/*
+	 * In case we exclude kernel IPs or are somehow not in interrupt
+	 * context, provide the next best thing, the user IP.
+	 */
+	if ((event->attr.exclude_kernel || !regs) &&
+			!event->attr.exclude_user)
+		regs = task_pt_regs(current);
+
+	if (regs) {
+		if (perf_event_overflow(event, 0, &data, regs))
+			ret = HRTIMER_NORESTART;
+	}
+
+	period = max_t(u64, 10000, event->hw.sample_period);
+	hrtimer_forward_now(hrtimer, ns_to_ktime(period));
+
+	return ret;
+}
+
+/*
+ * Software event: cpu wall time clock
+ */
+
+static void cpu_clock_perf_event_update(struct perf_event *event)
+{
+	int cpu = raw_smp_processor_id();
+	s64 prev;
+	u64 now;
+
+	now = cpu_clock(cpu);
+	prev = atomic64_read(&event->hw.prev_count);
+	atomic64_set(&event->hw.prev_count, now);
+	atomic64_add(now - prev, &event->count);
+}
+
+static int cpu_clock_perf_event_enable(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	int cpu = raw_smp_processor_id();
+
+	atomic64_set(&hwc->prev_count, cpu_clock(cpu));
+	hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hwc->hrtimer.function = perf_swevent_hrtimer;
+	if (hwc->sample_period) {
+		u64 period = max_t(u64, 10000, hwc->sample_period);
+		__hrtimer_start_range_ns(&hwc->hrtimer,
+				ns_to_ktime(period), 0,
+				HRTIMER_MODE_REL, 0);
+	}
+
+	return 0;
+}
+
+static void cpu_clock_perf_event_disable(struct perf_event *event)
+{
+	if (event->hw.sample_period)
+		hrtimer_cancel(&event->hw.hrtimer);
+	cpu_clock_perf_event_update(event);
+}
+
+static void cpu_clock_perf_event_read(struct perf_event *event)
+{
+	cpu_clock_perf_event_update(event);
+}
+
+static const struct pmu perf_ops_cpu_clock = {
+	.enable		= cpu_clock_perf_event_enable,
+	.disable	= cpu_clock_perf_event_disable,
+	.read		= cpu_clock_perf_event_read,
+};
+
+/*
+ * Software event: task time clock
+ */
+
+static void task_clock_perf_event_update(struct perf_event *event, u64 now)
+{
+	u64 prev;
+	s64 delta;
+
+	prev = atomic64_xchg(&event->hw.prev_count, now);
+	delta = now - prev;
+	atomic64_add(delta, &event->count);
+}
+
+static int task_clock_perf_event_enable(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	u64 now;
+
+	now = event->ctx->time;
+
+	atomic64_set(&hwc->prev_count, now);
+	hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hwc->hrtimer.function = perf_swevent_hrtimer;
+	if (hwc->sample_period) {
+		u64 period = max_t(u64, 10000, hwc->sample_period);
+		__hrtimer_start_range_ns(&hwc->hrtimer,
+				ns_to_ktime(period), 0,
+				HRTIMER_MODE_REL, 0);
+	}
+
+	return 0;
+}
+
+static void task_clock_perf_event_disable(struct perf_event *event)
+{
+	if (event->hw.sample_period)
+		hrtimer_cancel(&event->hw.hrtimer);
+	task_clock_perf_event_update(event, event->ctx->time);
+
+}
+
+static void task_clock_perf_event_read(struct perf_event *event)
+{
+	u64 time;
+
+	if (!in_nmi()) {
+		update_context_time(event->ctx);
+		time = event->ctx->time;
+	} else {
+		u64 now = perf_clock();
+		u64 delta = now - event->ctx->timestamp;
+		time = event->ctx->time + delta;
+	}
+
+	task_clock_perf_event_update(event, time);
+}
+
+static const struct pmu perf_ops_task_clock = {
+	.enable		= task_clock_perf_event_enable,
+	.disable	= task_clock_perf_event_disable,
+	.read		= task_clock_perf_event_read,
+};
+
+#ifdef CONFIG_EVENT_PROFILE
+void perf_tp_event(int event_id, u64 addr, u64 count, void *record,
+			  int entry_size)
+{
+	struct perf_raw_record raw = {
+		.size = entry_size,
+		.data = record,
+	};
+
+	struct perf_sample_data data = {
+		.addr = addr,
+		.raw = &raw,
+	};
+
+	struct pt_regs *regs = get_irq_regs();
+
+	if (!regs)
+		regs = task_pt_regs(current);
+
+	do_perf_sw_event(PERF_TYPE_TRACEPOINT, event_id, count, 1,
+				&data, regs);
+}
+EXPORT_SYMBOL_GPL(perf_tp_event);
+
+extern int ftrace_profile_enable(int);
+extern void ftrace_profile_disable(int);
+
+static void tp_perf_event_destroy(struct perf_event *event)
+{
+	ftrace_profile_disable(event->attr.config);
+}
+
+static const struct pmu *tp_perf_event_init(struct perf_event *event)
+{
+	/*
+	 * Raw tracepoint data is a severe data leak, only allow root to
+	 * have these.
+	 */
+	if ((event->attr.sample_type & PERF_SAMPLE_RAW) &&
+			perf_paranoid_tracepoint_raw() &&
+			!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+
+	if (ftrace_profile_enable(event->attr.config))
+		return NULL;
+
+	event->destroy = tp_perf_event_destroy;
+
+	return &perf_ops_generic;
+}
+#else
+static const struct pmu *tp_perf_event_init(struct perf_event *event)
+{
+	return NULL;
+}
+#endif
+
+atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX];
+
+static void sw_perf_event_destroy(struct perf_event *event)
+{
+	u64 event_id = event->attr.config;
+
+	WARN_ON(event->parent);
+
+	atomic_dec(&perf_swevent_enabled[event_id]);
+}
+
+static const struct pmu *sw_perf_event_init(struct perf_event *event)
+{
+	const struct pmu *pmu = NULL;
+	u64 event_id = event->attr.config;
+
+	/*
+	 * Software events (currently) can't in general distinguish
+	 * between user, kernel and hypervisor events.
+	 * However, context switches and cpu migrations are considered
+	 * to be kernel events, and page faults are never hypervisor
+	 * events.
+	 */
+	switch (event_id) {
+	case PERF_COUNT_SW_CPU_CLOCK:
+		pmu = &perf_ops_cpu_clock;
+
+		break;
+	case PERF_COUNT_SW_TASK_CLOCK:
+		/*
+		 * If the user instantiates this as a per-cpu event,
+		 * use the cpu_clock event instead.
+		 */
+		if (event->ctx->task)
+			pmu = &perf_ops_task_clock;
+		else
+			pmu = &perf_ops_cpu_clock;
+
+		break;
+	case PERF_COUNT_SW_PAGE_FAULTS:
+	case PERF_COUNT_SW_PAGE_FAULTS_MIN:
+	case PERF_COUNT_SW_PAGE_FAULTS_MAJ:
+	case PERF_COUNT_SW_CONTEXT_SWITCHES:
+	case PERF_COUNT_SW_CPU_MIGRATIONS:
+		if (!event->parent) {
+			atomic_inc(&perf_swevent_enabled[event_id]);
+			event->destroy = sw_perf_event_destroy;
+		}
+		pmu = &perf_ops_generic;
+		break;
+	}
+
+	return pmu;
+}
+
+/*
+ * Allocate and initialize a event structure
+ */
+static struct perf_event *
+perf_event_alloc(struct perf_event_attr *attr,
+		   int cpu,
+		   struct perf_event_context *ctx,
+		   struct perf_event *group_leader,
+		   struct perf_event *parent_event,
+		   gfp_t gfpflags)
+{
+	const struct pmu *pmu;
+	struct perf_event *event;
+	struct hw_perf_event *hwc;
+	long err;
+
+	event = kzalloc(sizeof(*event), gfpflags);
+	if (!event)
+		return ERR_PTR(-ENOMEM);
+
+	/*
+	 * Single events are their own group leaders, with an
+	 * empty sibling list:
+	 */
+	if (!group_leader)
+		group_leader = event;
+
+	mutex_init(&event->child_mutex);
+	INIT_LIST_HEAD(&event->child_list);
+
+	INIT_LIST_HEAD(&event->group_entry);
+	INIT_LIST_HEAD(&event->event_entry);
+	INIT_LIST_HEAD(&event->sibling_list);
+	init_waitqueue_head(&event->waitq);
+
+	mutex_init(&event->mmap_mutex);
+
+	event->cpu		= cpu;
+	event->attr		= *attr;
+	event->group_leader	= group_leader;
+	event->pmu		= NULL;
+	event->ctx		= ctx;
+	event->oncpu		= -1;
+
+	event->parent		= parent_event;
+
+	event->ns		= get_pid_ns(current->nsproxy->pid_ns);
+	event->id		= atomic64_inc_return(&perf_event_id);
+
+	event->state		= PERF_EVENT_STATE_INACTIVE;
+
+	if (attr->disabled)
+		event->state = PERF_EVENT_STATE_OFF;
+
+	pmu = NULL;
+
+	hwc = &event->hw;
+	hwc->sample_period = attr->sample_period;
+	if (attr->freq && attr->sample_freq)
+		hwc->sample_period = 1;
+	hwc->last_period = hwc->sample_period;
+
+	atomic64_set(&hwc->period_left, hwc->sample_period);
+
+	/*
+	 * we currently do not support PERF_FORMAT_GROUP on inherited events
+	 */
+	if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP))
+		goto done;
+
+	switch (attr->type) {
+	case PERF_TYPE_RAW:
+	case PERF_TYPE_HARDWARE:
+	case PERF_TYPE_HW_CACHE:
+		pmu = hw_perf_event_init(event);
+		break;
+
+	case PERF_TYPE_SOFTWARE:
+		pmu = sw_perf_event_init(event);
+		break;
+
+	case PERF_TYPE_TRACEPOINT:
+		pmu = tp_perf_event_init(event);
+		break;
+
+	default:
+		break;
+	}
+done:
+	err = 0;
+	if (!pmu)
+		err = -EINVAL;
+	else if (IS_ERR(pmu))
+		err = PTR_ERR(pmu);
+
+	if (err) {
+		if (event->ns)
+			put_pid_ns(event->ns);
+		kfree(event);
+		return ERR_PTR(err);
+	}
+
+	event->pmu = pmu;
+
+	if (!event->parent) {
+		atomic_inc(&nr_events);
+		if (event->attr.mmap)
+			atomic_inc(&nr_mmap_events);
+		if (event->attr.comm)
+			atomic_inc(&nr_comm_events);
+		if (event->attr.task)
+			atomic_inc(&nr_task_events);
+	}
+
+	return event;
+}
+
+static int perf_copy_attr(struct perf_event_attr __user *uattr,
+			  struct perf_event_attr *attr)
+{
+	u32 size;
+	int ret;
+
+	if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0))
+		return -EFAULT;
+
+	/*
+	 * zero the full structure, so that a short copy will be nice.
+	 */
+	memset(attr, 0, sizeof(*attr));
+
+	ret = get_user(size, &uattr->size);
+	if (ret)
+		return ret;
+
+	if (size > PAGE_SIZE)	/* silly large */
+		goto err_size;
+
+	if (!size)		/* abi compat */
+		size = PERF_ATTR_SIZE_VER0;
+
+	if (size < PERF_ATTR_SIZE_VER0)
+		goto err_size;
+
+	/*
+	 * If we're handed a bigger struct than we know of,
+	 * ensure all the unknown bits are 0 - i.e. new
+	 * user-space does not rely on any kernel feature
+	 * extensions we dont know about yet.
+	 */
+	if (size > sizeof(*attr)) {
+		unsigned char __user *addr;
+		unsigned char __user *end;
+		unsigned char val;
+
+		addr = (void __user *)uattr + sizeof(*attr);
+		end  = (void __user *)uattr + size;
+
+		for (; addr < end; addr++) {
+			ret = get_user(val, addr);
+			if (ret)
+				return ret;
+			if (val)
+				goto err_size;
+		}
+		size = sizeof(*attr);
+	}
+
+	ret = copy_from_user(attr, uattr, size);
+	if (ret)
+		return -EFAULT;
+
+	/*
+	 * If the type exists, the corresponding creation will verify
+	 * the attr->config.
+	 */
+	if (attr->type >= PERF_TYPE_MAX)
+		return -EINVAL;
+
+	if (attr->__reserved_1 || attr->__reserved_2 || attr->__reserved_3)
+		return -EINVAL;
+
+	if (attr->sample_type & ~(PERF_SAMPLE_MAX-1))
+		return -EINVAL;
+
+	if (attr->read_format & ~(PERF_FORMAT_MAX-1))
+		return -EINVAL;
+
+out:
+	return ret;
+
+err_size:
+	put_user(sizeof(*attr), &uattr->size);
+	ret = -E2BIG;
+	goto out;
+}
+
+int perf_event_set_output(struct perf_event *event, int output_fd)
+{
+	struct perf_event *output_event = NULL;
+	struct file *output_file = NULL;
+	struct perf_event *old_output;
+	int fput_needed = 0;
+	int ret = -EINVAL;
+
+	if (!output_fd)
+		goto set;
+
+	output_file = fget_light(output_fd, &fput_needed);
+	if (!output_file)
+		return -EBADF;
+
+	if (output_file->f_op != &perf_fops)
+		goto out;
+
+	output_event = output_file->private_data;
+
+	/* Don't chain output fds */
+	if (output_event->output)
+		goto out;
+
+	/* Don't set an output fd when we already have an output channel */
+	if (event->data)
+		goto out;
+
+	atomic_long_inc(&output_file->f_count);
+
+set:
+	mutex_lock(&event->mmap_mutex);
+	old_output = event->output;
+	rcu_assign_pointer(event->output, output_event);
+	mutex_unlock(&event->mmap_mutex);
+
+	if (old_output) {
+		/*
+		 * we need to make sure no existing perf_output_*()
+		 * is still referencing this event.
+		 */
+		synchronize_rcu();
+		fput(old_output->filp);
+	}
+
+	ret = 0;
+out:
+	fput_light(output_file, fput_needed);
+	return ret;
+}
+
+/**
+ * sys_perf_event_open - open a performance event, associate it to a task/cpu
+ *
+ * @attr_uptr:	event_id type attributes for monitoring/sampling
+ * @pid:		target pid
+ * @cpu:		target cpu
+ * @group_fd:		group leader event fd
+ */
+SYSCALL_DEFINE5(perf_event_open,
+		struct perf_event_attr __user *, attr_uptr,
+		pid_t, pid, int, cpu, int, group_fd, unsigned long, flags)
+{
+	struct perf_event *event, *group_leader;
+	struct perf_event_attr attr;
+	struct perf_event_context *ctx;
+	struct file *event_file = NULL;
+	struct file *group_file = NULL;
+	int fput_needed = 0;
+	int fput_needed2 = 0;
+	int err;
+
+	/* for future expandability... */
+	if (flags & ~(PERF_FLAG_FD_NO_GROUP | PERF_FLAG_FD_OUTPUT))
+		return -EINVAL;
+
+	err = perf_copy_attr(attr_uptr, &attr);
+	if (err)
+		return err;
+
+	if (!attr.exclude_kernel) {
+		if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN))
+			return -EACCES;
+	}
+
+	if (attr.freq) {
+		if (attr.sample_freq > sysctl_perf_event_sample_rate)
+			return -EINVAL;
+	}
+
+	/*
+	 * Get the target context (task or percpu):
+	 */
+	ctx = find_get_context(pid, cpu);
+	if (IS_ERR(ctx))
+		return PTR_ERR(ctx);
+
+	/*
+	 * Look up the group leader (we will attach this event to it):
+	 */
+	group_leader = NULL;
+	if (group_fd != -1 && !(flags & PERF_FLAG_FD_NO_GROUP)) {
+		err = -EINVAL;
+		group_file = fget_light(group_fd, &fput_needed);
+		if (!group_file)
+			goto err_put_context;
+		if (group_file->f_op != &perf_fops)
+			goto err_put_context;
+
+		group_leader = group_file->private_data;
+		/*
+		 * Do not allow a recursive hierarchy (this new sibling
+		 * becoming part of another group-sibling):
+		 */
+		if (group_leader->group_leader != group_leader)
+			goto err_put_context;
+		/*
+		 * Do not allow to attach to a group in a different
+		 * task or CPU context:
+		 */
+		if (group_leader->ctx != ctx)
+			goto err_put_context;
+		/*
+		 * Only a group leader can be exclusive or pinned
+		 */
+		if (attr.exclusive || attr.pinned)
+			goto err_put_context;
+	}
+
+	event = perf_event_alloc(&attr, cpu, ctx, group_leader,
+				     NULL, GFP_KERNEL);
+	err = PTR_ERR(event);
+	if (IS_ERR(event))
+		goto err_put_context;
+
+	err = anon_inode_getfd("[perf_event]", &perf_fops, event, 0);
+	if (err < 0)
+		goto err_free_put_context;
+
+	event_file = fget_light(err, &fput_needed2);
+	if (!event_file)
+		goto err_free_put_context;
+
+	if (flags & PERF_FLAG_FD_OUTPUT) {
+		err = perf_event_set_output(event, group_fd);
+		if (err)
+			goto err_fput_free_put_context;
+	}
+
+	event->filp = event_file;
+	WARN_ON_ONCE(ctx->parent_ctx);
+	mutex_lock(&ctx->mutex);
+	perf_install_in_context(ctx, event, cpu);
+	++ctx->generation;
+	mutex_unlock(&ctx->mutex);
+
+	event->owner = current;
+	get_task_struct(current);
+	mutex_lock(&current->perf_event_mutex);
+	list_add_tail(&event->owner_entry, &current->perf_event_list);
+	mutex_unlock(&current->perf_event_mutex);
+
+err_fput_free_put_context:
+	fput_light(event_file, fput_needed2);
+
+err_free_put_context:
+	if (err < 0)
+		kfree(event);
+
+err_put_context:
+	if (err < 0)
+		put_ctx(ctx);
+
+	fput_light(group_file, fput_needed);
+
+	return err;
+}
+
+/*
+ * inherit a event from parent task to child task:
+ */
+static struct perf_event *
+inherit_event(struct perf_event *parent_event,
+	      struct task_struct *parent,
+	      struct perf_event_context *parent_ctx,
+	      struct task_struct *child,
+	      struct perf_event *group_leader,
+	      struct perf_event_context *child_ctx)
+{
+	struct perf_event *child_event;
+
+	/*
+	 * Instead of creating recursive hierarchies of events,
+	 * we link inherited events back to the original parent,
+	 * which has a filp for sure, which we use as the reference
+	 * count:
+	 */
+	if (parent_event->parent)
+		parent_event = parent_event->parent;
+
+	child_event = perf_event_alloc(&parent_event->attr,
+					   parent_event->cpu, child_ctx,
+					   group_leader, parent_event,
+					   GFP_KERNEL);
+	if (IS_ERR(child_event))
+		return child_event;
+	get_ctx(child_ctx);
+
+	/*
+	 * Make the child state follow the state of the parent event,
+	 * not its attr.disabled bit.  We hold the parent's mutex,
+	 * so we won't race with perf_event_{en, dis}able_family.
+	 */
+	if (parent_event->state >= PERF_EVENT_STATE_INACTIVE)
+		child_event->state = PERF_EVENT_STATE_INACTIVE;
+	else
+		child_event->state = PERF_EVENT_STATE_OFF;
+
+	if (parent_event->attr.freq)
+		child_event->hw.sample_period = parent_event->hw.sample_period;
+
+	/*
+	 * Link it up in the child's context:
+	 */
+	add_event_to_ctx(child_event, child_ctx);
+
+	/*
+	 * Get a reference to the parent filp - we will fput it
+	 * when the child event exits. This is safe to do because
+	 * we are in the parent and we know that the filp still
+	 * exists and has a nonzero count:
+	 */
+	atomic_long_inc(&parent_event->filp->f_count);
+
+	/*
+	 * Link this into the parent event's child list
+	 */
+	WARN_ON_ONCE(parent_event->ctx->parent_ctx);
+	mutex_lock(&parent_event->child_mutex);
+	list_add_tail(&child_event->child_list, &parent_event->child_list);
+	mutex_unlock(&parent_event->child_mutex);
+
+	return child_event;
+}
+
+static int inherit_group(struct perf_event *parent_event,
+	      struct task_struct *parent,
+	      struct perf_event_context *parent_ctx,
+	      struct task_struct *child,
+	      struct perf_event_context *child_ctx)
+{
+	struct perf_event *leader;
+	struct perf_event *sub;
+	struct perf_event *child_ctr;
+
+	leader = inherit_event(parent_event, parent, parent_ctx,
+				 child, NULL, child_ctx);
+	if (IS_ERR(leader))
+		return PTR_ERR(leader);
+	list_for_each_entry(sub, &parent_event->sibling_list, group_entry) {
+		child_ctr = inherit_event(sub, parent, parent_ctx,
+					    child, leader, child_ctx);
+		if (IS_ERR(child_ctr))
+			return PTR_ERR(child_ctr);
+	}
+	return 0;
+}
+
+static void sync_child_event(struct perf_event *child_event,
+			       struct task_struct *child)
+{
+	struct perf_event *parent_event = child_event->parent;
+	u64 child_val;
+
+	if (child_event->attr.inherit_stat)
+		perf_event_read_event(child_event, child);
+
+	child_val = atomic64_read(&child_event->count);
+
+	/*
+	 * Add back the child's count to the parent's count:
+	 */
+	atomic64_add(child_val, &parent_event->count);
+	atomic64_add(child_event->total_time_enabled,
+		     &parent_event->child_total_time_enabled);
+	atomic64_add(child_event->total_time_running,
+		     &parent_event->child_total_time_running);
+
+	/*
+	 * Remove this event from the parent's list
+	 */
+	WARN_ON_ONCE(parent_event->ctx->parent_ctx);
+	mutex_lock(&parent_event->child_mutex);
+	list_del_init(&child_event->child_list);
+	mutex_unlock(&parent_event->child_mutex);
+
+	/*
+	 * Release the parent event, if this was the last
+	 * reference to it.
+	 */
+	fput(parent_event->filp);
+}
+
+static void
+__perf_event_exit_task(struct perf_event *child_event,
+			 struct perf_event_context *child_ctx,
+			 struct task_struct *child)
+{
+	struct perf_event *parent_event;
+
+	update_event_times(child_event);
+	perf_event_remove_from_context(child_event);
+
+	parent_event = child_event->parent;
+	/*
+	 * It can happen that parent exits first, and has events
+	 * that are still around due to the child reference. These
+	 * events need to be zapped - but otherwise linger.
+	 */
+	if (parent_event) {
+		sync_child_event(child_event, child);
+		free_event(child_event);
+	}
+}
+
+/*
+ * When a child task exits, feed back event values to parent events.
+ */
+void perf_event_exit_task(struct task_struct *child)
+{
+	struct perf_event *child_event, *tmp;
+	struct perf_event_context *child_ctx;
+	unsigned long flags;
+
+	if (likely(!child->perf_event_ctxp)) {
+		perf_event_task(child, NULL, 0);
+		return;
+	}
+
+	local_irq_save(flags);
+	/*
+	 * We can't reschedule here because interrupts are disabled,
+	 * and either child is current or it is a task that can't be
+	 * scheduled, so we are now safe from rescheduling changing
+	 * our context.
+	 */
+	child_ctx = child->perf_event_ctxp;
+	__perf_event_task_sched_out(child_ctx);
+
+	/*
+	 * Take the context lock here so that if find_get_context is
+	 * reading child->perf_event_ctxp, we wait until it has
+	 * incremented the context's refcount before we do put_ctx below.
+	 */
+	spin_lock(&child_ctx->lock);
+	child->perf_event_ctxp = NULL;
+	/*
+	 * If this context is a clone; unclone it so it can't get
+	 * swapped to another process while we're removing all
+	 * the events from it.
+	 */
+	unclone_ctx(child_ctx);
+	spin_unlock_irqrestore(&child_ctx->lock, flags);
+
+	/*
+	 * Report the task dead after unscheduling the events so that we
+	 * won't get any samples after PERF_RECORD_EXIT. We can however still
+	 * get a few PERF_RECORD_READ events.
+	 */
+	perf_event_task(child, child_ctx, 0);
+
+	/*
+	 * We can recurse on the same lock type through:
+	 *
+	 *   __perf_event_exit_task()
+	 *     sync_child_event()
+	 *       fput(parent_event->filp)
+	 *         perf_release()
+	 *           mutex_lock(&ctx->mutex)
+	 *
+	 * But since its the parent context it won't be the same instance.
+	 */
+	mutex_lock_nested(&child_ctx->mutex, SINGLE_DEPTH_NESTING);
+
+again:
+	list_for_each_entry_safe(child_event, tmp, &child_ctx->group_list,
+				 group_entry)
+		__perf_event_exit_task(child_event, child_ctx, child);
+
+	/*
+	 * If the last event was a group event, it will have appended all
+	 * its siblings to the list, but we obtained 'tmp' before that which
+	 * will still point to the list head terminating the iteration.
+	 */
+	if (!list_empty(&child_ctx->group_list))
+		goto again;
+
+	mutex_unlock(&child_ctx->mutex);
+
+	put_ctx(child_ctx);
+}
+
+/*
+ * free an unexposed, unused context as created by inheritance by
+ * init_task below, used by fork() in case of fail.
+ */
+void perf_event_free_task(struct task_struct *task)
+{
+	struct perf_event_context *ctx = task->perf_event_ctxp;
+	struct perf_event *event, *tmp;
+
+	if (!ctx)
+		return;
+
+	mutex_lock(&ctx->mutex);
+again:
+	list_for_each_entry_safe(event, tmp, &ctx->group_list, group_entry) {
+		struct perf_event *parent = event->parent;
+
+		if (WARN_ON_ONCE(!parent))
+			continue;
+
+		mutex_lock(&parent->child_mutex);
+		list_del_init(&event->child_list);
+		mutex_unlock(&parent->child_mutex);
+
+		fput(parent->filp);
+
+		list_del_event(event, ctx);
+		free_event(event);
+	}
+
+	if (!list_empty(&ctx->group_list))
+		goto again;
+
+	mutex_unlock(&ctx->mutex);
+
+	put_ctx(ctx);
+}
+
+/*
+ * Initialize the perf_event context in task_struct
+ */
+int perf_event_init_task(struct task_struct *child)
+{
+	struct perf_event_context *child_ctx, *parent_ctx;
+	struct perf_event_context *cloned_ctx;
+	struct perf_event *event;
+	struct task_struct *parent = current;
+	int inherited_all = 1;
+	int ret = 0;
+
+	child->perf_event_ctxp = NULL;
+
+	mutex_init(&child->perf_event_mutex);
+	INIT_LIST_HEAD(&child->perf_event_list);
+
+	if (likely(!parent->perf_event_ctxp))
+		return 0;
+
+	/*
+	 * This is executed from the parent task context, so inherit
+	 * events that have been marked for cloning.
+	 * First allocate and initialize a context for the child.
+	 */
+
+	child_ctx = kmalloc(sizeof(struct perf_event_context), GFP_KERNEL);
+	if (!child_ctx)
+		return -ENOMEM;
+
+	__perf_event_init_context(child_ctx, child);
+	child->perf_event_ctxp = child_ctx;
+	get_task_struct(child);
+
+	/*
+	 * If the parent's context is a clone, pin it so it won't get
+	 * swapped under us.
+	 */
+	parent_ctx = perf_pin_task_context(parent);
+
+	/*
+	 * No need to check if parent_ctx != NULL here; since we saw
+	 * it non-NULL earlier, the only reason for it to become NULL
+	 * is if we exit, and since we're currently in the middle of
+	 * a fork we can't be exiting at the same time.
+	 */
+
+	/*
+	 * Lock the parent list. No need to lock the child - not PID
+	 * hashed yet and not running, so nobody can access it.
+	 */
+	mutex_lock(&parent_ctx->mutex);
+
+	/*
+	 * We dont have to disable NMIs - we are only looking at
+	 * the list, not manipulating it:
+	 */
+	list_for_each_entry_rcu(event, &parent_ctx->event_list, event_entry) {
+		if (event != event->group_leader)
+			continue;
+
+		if (!event->attr.inherit) {
+			inherited_all = 0;
+			continue;
+		}
+
+		ret = inherit_group(event, parent, parent_ctx,
+					     child, child_ctx);
+		if (ret) {
+			inherited_all = 0;
+			break;
+		}
+	}
+
+	if (inherited_all) {
+		/*
+		 * Mark the child context as a clone of the parent
+		 * context, or of whatever the parent is a clone of.
+		 * Note that if the parent is a clone, it could get
+		 * uncloned at any point, but that doesn't matter
+		 * because the list of events and the generation
+		 * count can't have changed since we took the mutex.
+		 */
+		cloned_ctx = rcu_dereference(parent_ctx->parent_ctx);
+		if (cloned_ctx) {
+			child_ctx->parent_ctx = cloned_ctx;
+			child_ctx->parent_gen = parent_ctx->parent_gen;
+		} else {
+			child_ctx->parent_ctx = parent_ctx;
+			child_ctx->parent_gen = parent_ctx->generation;
+		}
+		get_ctx(child_ctx->parent_ctx);
+	}
+
+	mutex_unlock(&parent_ctx->mutex);
+
+	perf_unpin_context(parent_ctx);
+
+	return ret;
+}
+
+static void __cpuinit perf_event_init_cpu(int cpu)
+{
+	struct perf_cpu_context *cpuctx;
+
+	cpuctx = &per_cpu(perf_cpu_context, cpu);
+	__perf_event_init_context(&cpuctx->ctx, NULL);
+
+	spin_lock(&perf_resource_lock);
+	cpuctx->max_pertask = perf_max_events - perf_reserved_percpu;
+	spin_unlock(&perf_resource_lock);
+
+	hw_perf_event_setup(cpu);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static void __perf_event_exit_cpu(void *info)
+{
+	struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+	struct perf_event_context *ctx = &cpuctx->ctx;
+	struct perf_event *event, *tmp;
+
+	list_for_each_entry_safe(event, tmp, &ctx->group_list, group_entry)
+		__perf_event_remove_from_context(event);
+}
+static void perf_event_exit_cpu(int cpu)
+{
+	struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
+	struct perf_event_context *ctx = &cpuctx->ctx;
+
+	mutex_lock(&ctx->mutex);
+	smp_call_function_single(cpu, __perf_event_exit_cpu, NULL, 1);
+	mutex_unlock(&ctx->mutex);
+}
+#else
+static inline void perf_event_exit_cpu(int cpu) { }
+#endif
+
+static int __cpuinit
+perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu)
+{
+	unsigned int cpu = (long)hcpu;
+
+	switch (action) {
+
+	case CPU_UP_PREPARE:
+	case CPU_UP_PREPARE_FROZEN:
+		perf_event_init_cpu(cpu);
+		break;
+
+	case CPU_ONLINE:
+	case CPU_ONLINE_FROZEN:
+		hw_perf_event_setup_online(cpu);
+		break;
+
+	case CPU_DOWN_PREPARE:
+	case CPU_DOWN_PREPARE_FROZEN:
+		perf_event_exit_cpu(cpu);
+		break;
+
+	default:
+		break;
+	}
+
+	return NOTIFY_OK;
+}
+
+/*
+ * This has to have a higher priority than migration_notifier in sched.c.
+ */
+static struct notifier_block __cpuinitdata perf_cpu_nb = {
+	.notifier_call		= perf_cpu_notify,
+	.priority		= 20,
+};
+
+void __init perf_event_init(void)
+{
+	perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_UP_PREPARE,
+			(void *)(long)smp_processor_id());
+	perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_ONLINE,
+			(void *)(long)smp_processor_id());
+	register_cpu_notifier(&perf_cpu_nb);
+}
+
+static ssize_t perf_show_reserve_percpu(struct sysdev_class *class, char *buf)
+{
+	return sprintf(buf, "%d\n", perf_reserved_percpu);
+}
+
+static ssize_t
+perf_set_reserve_percpu(struct sysdev_class *class,
+			const char *buf,
+			size_t count)
+{
+	struct perf_cpu_context *cpuctx;
+	unsigned long val;
+	int err, cpu, mpt;
+
+	err = strict_strtoul(buf, 10, &val);
+	if (err)
+		return err;
+	if (val > perf_max_events)
+		return -EINVAL;
+
+	spin_lock(&perf_resource_lock);
+	perf_reserved_percpu = val;
+	for_each_online_cpu(cpu) {
+		cpuctx = &per_cpu(perf_cpu_context, cpu);
+		spin_lock_irq(&cpuctx->ctx.lock);
+		mpt = min(perf_max_events - cpuctx->ctx.nr_events,
+			  perf_max_events - perf_reserved_percpu);
+		cpuctx->max_pertask = mpt;
+		spin_unlock_irq(&cpuctx->ctx.lock);
+	}
+	spin_unlock(&perf_resource_lock);
+
+	return count;
+}
+
+static ssize_t perf_show_overcommit(struct sysdev_class *class, char *buf)
+{
+	return sprintf(buf, "%d\n", perf_overcommit);
+}
+
+static ssize_t
+perf_set_overcommit(struct sysdev_class *class, const char *buf, size_t count)
+{
+	unsigned long val;
+	int err;
+
+	err = strict_strtoul(buf, 10, &val);
+	if (err)
+		return err;
+	if (val > 1)
+		return -EINVAL;
+
+	spin_lock(&perf_resource_lock);
+	perf_overcommit = val;
+	spin_unlock(&perf_resource_lock);
+
+	return count;
+}
+
+static SYSDEV_CLASS_ATTR(
+				reserve_percpu,
+				0644,
+				perf_show_reserve_percpu,
+				perf_set_reserve_percpu
+			);
+
+static SYSDEV_CLASS_ATTR(
+				overcommit,
+				0644,
+				perf_show_overcommit,
+				perf_set_overcommit
+			);
+
+static struct attribute *perfclass_attrs[] = {
+	&attr_reserve_percpu.attr,
+	&attr_overcommit.attr,
+	NULL
+};
+
+static struct attribute_group perfclass_attr_group = {
+	.attrs			= perfclass_attrs,
+	.name			= "perf_events",
+};
+
+static int __init perf_event_sysfs_init(void)
+{
+	return sysfs_create_group(&cpu_sysdev_class.kset.kobj,
+				  &perfclass_attr_group);
+}
+device_initcall(perf_event_sysfs_init);
diff --git a/kernel/pid.c b/kernel/pid.c
index 31310b5..d3f722d 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -40,7 +40,7 @@
 #define pid_hashfn(nr, ns)	\
 	hash_long((unsigned long)nr + (unsigned long)ns, pidhash_shift)
 static struct hlist_head *pid_hash;
-static int pidhash_shift;
+static unsigned int pidhash_shift = 4;
 struct pid init_struct_pid = INIT_STRUCT_PID;
 
 int pid_max = PID_MAX_DEFAULT;
@@ -499,19 +499,12 @@ struct pid *find_ge_pid(int nr, struct pid_namespace *ns)
 void __init pidhash_init(void)
 {
 	int i, pidhash_size;
-	unsigned long megabytes = nr_kernel_pages >> (20 - PAGE_SHIFT);
 
-	pidhash_shift = max(4, fls(megabytes * 4));
-	pidhash_shift = min(12, pidhash_shift);
+	pid_hash = alloc_large_system_hash("PID", sizeof(*pid_hash), 0, 18,
+					   HASH_EARLY | HASH_SMALL,
+					   &pidhash_shift, NULL, 4096);
 	pidhash_size = 1 << pidhash_shift;
 
-	printk("PID hash table entries: %d (order: %d, %Zd bytes)\n",
-		pidhash_size, pidhash_shift,
-		pidhash_size * sizeof(struct hlist_head));
-
-	pid_hash = alloc_bootmem(pidhash_size *	sizeof(*(pid_hash)));
-	if (!pid_hash)
-		panic("Could not alloc pidhash!\n");
 	for (i = 0; i < pidhash_size; i++)
 		INIT_HLIST_HEAD(&pid_hash[i]);
 }
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index e33a21c..5c9dc22 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -8,17 +8,18 @@
 #include <linux/math64.h>
 #include <asm/uaccess.h>
 #include <linux/kernel_stat.h>
+#include <trace/events/timer.h>
 
 /*
  * Called after updating RLIMIT_CPU to set timer expiration if necessary.
  */
 void update_rlimit_cpu(unsigned long rlim_new)
 {
-	cputime_t cputime;
+	cputime_t cputime = secs_to_cputime(rlim_new);
+	struct signal_struct *const sig = current->signal;
 
-	cputime = secs_to_cputime(rlim_new);
-	if (cputime_eq(current->signal->it_prof_expires, cputime_zero) ||
-	    cputime_gt(current->signal->it_prof_expires, cputime)) {
+	if (cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) ||
+	    cputime_gt(sig->it[CPUCLOCK_PROF].expires, cputime)) {
 		spin_lock_irq(&current->sighand->siglock);
 		set_process_cpu_timer(current, CPUCLOCK_PROF, &cputime, NULL);
 		spin_unlock_irq(&current->sighand->siglock);
@@ -542,6 +543,17 @@ static void clear_dead_task(struct k_itimer *timer, union cpu_time_count now)
 					     now);
 }
 
+static inline int expires_gt(cputime_t expires, cputime_t new_exp)
+{
+	return cputime_eq(expires, cputime_zero) ||
+	       cputime_gt(expires, new_exp);
+}
+
+static inline int expires_le(cputime_t expires, cputime_t new_exp)
+{
+	return !cputime_eq(expires, cputime_zero) &&
+	       cputime_le(expires, new_exp);
+}
 /*
  * Insert the timer on the appropriate list before any timers that
  * expire later.  This must be called with the tasklist_lock held
@@ -586,34 +598,32 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now)
 		 */
 
 		if (CPUCLOCK_PERTHREAD(timer->it_clock)) {
+			union cpu_time_count *exp = &nt->expires;
+
 			switch (CPUCLOCK_WHICH(timer->it_clock)) {
 			default:
 				BUG();
 			case CPUCLOCK_PROF:
-				if (cputime_eq(p->cputime_expires.prof_exp,
-					       cputime_zero) ||
-				    cputime_gt(p->cputime_expires.prof_exp,
-					       nt->expires.cpu))
-					p->cputime_expires.prof_exp =
-						nt->expires.cpu;
+				if (expires_gt(p->cputime_expires.prof_exp,
+					       exp->cpu))
+					p->cputime_expires.prof_exp = exp->cpu;
 				break;
 			case CPUCLOCK_VIRT:
-				if (cputime_eq(p->cputime_expires.virt_exp,
-					       cputime_zero) ||
-				    cputime_gt(p->cputime_expires.virt_exp,
-					       nt->expires.cpu))
-					p->cputime_expires.virt_exp =
-						nt->expires.cpu;
+				if (expires_gt(p->cputime_expires.virt_exp,
+					       exp->cpu))
+					p->cputime_expires.virt_exp = exp->cpu;
 				break;
 			case CPUCLOCK_SCHED:
 				if (p->cputime_expires.sched_exp == 0 ||
-				    p->cputime_expires.sched_exp >
-							nt->expires.sched)
+				    p->cputime_expires.sched_exp > exp->sched)
 					p->cputime_expires.sched_exp =
-						nt->expires.sched;
+								exp->sched;
 				break;
 			}
 		} else {
+			struct signal_struct *const sig = p->signal;
+			union cpu_time_count *exp = &timer->it.cpu.expires;
+
 			/*
 			 * For a process timer, set the cached expiration time.
 			 */
@@ -621,30 +631,23 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now)
 			default:
 				BUG();
 			case CPUCLOCK_VIRT:
-				if (!cputime_eq(p->signal->it_virt_expires,
-						cputime_zero) &&
-				    cputime_lt(p->signal->it_virt_expires,
-					       timer->it.cpu.expires.cpu))
+				if (expires_le(sig->it[CPUCLOCK_VIRT].expires,
+					       exp->cpu))
 					break;
-				p->signal->cputime_expires.virt_exp =
-					timer->it.cpu.expires.cpu;
+				sig->cputime_expires.virt_exp = exp->cpu;
 				break;
 			case CPUCLOCK_PROF:
-				if (!cputime_eq(p->signal->it_prof_expires,
-						cputime_zero) &&
-				    cputime_lt(p->signal->it_prof_expires,
-					       timer->it.cpu.expires.cpu))
+				if (expires_le(sig->it[CPUCLOCK_PROF].expires,
+					       exp->cpu))
 					break;
-				i = p->signal->rlim[RLIMIT_CPU].rlim_cur;
+				i = sig->rlim[RLIMIT_CPU].rlim_cur;
 				if (i != RLIM_INFINITY &&
-				    i <= cputime_to_secs(timer->it.cpu.expires.cpu))
+				    i <= cputime_to_secs(exp->cpu))
 					break;
-				p->signal->cputime_expires.prof_exp =
-					timer->it.cpu.expires.cpu;
+				sig->cputime_expires.prof_exp = exp->cpu;
 				break;
 			case CPUCLOCK_SCHED:
-				p->signal->cputime_expires.sched_exp =
-					timer->it.cpu.expires.sched;
+				sig->cputime_expires.sched_exp = exp->sched;
 				break;
 			}
 		}
@@ -1071,6 +1074,40 @@ static void stop_process_timers(struct task_struct *tsk)
 	spin_unlock_irqrestore(&cputimer->lock, flags);
 }
 
+static u32 onecputick;
+
+static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it,
+			     cputime_t *expires, cputime_t cur_time, int signo)
+{
+	if (cputime_eq(it->expires, cputime_zero))
+		return;
+
+	if (cputime_ge(cur_time, it->expires)) {
+		if (!cputime_eq(it->incr, cputime_zero)) {
+			it->expires = cputime_add(it->expires, it->incr);
+			it->error += it->incr_error;
+			if (it->error >= onecputick) {
+				it->expires = cputime_sub(it->expires,
+							  cputime_one_jiffy);
+				it->error -= onecputick;
+			}
+		} else {
+			it->expires = cputime_zero;
+		}
+
+		trace_itimer_expire(signo == SIGPROF ?
+				    ITIMER_PROF : ITIMER_VIRTUAL,
+				    tsk->signal->leader_pid, cur_time);
+		__group_send_sig_info(signo, SEND_SIG_PRIV, tsk);
+	}
+
+	if (!cputime_eq(it->expires, cputime_zero) &&
+	    (cputime_eq(*expires, cputime_zero) ||
+	     cputime_lt(it->expires, *expires))) {
+		*expires = it->expires;
+	}
+}
+
 /*
  * Check for any per-thread CPU timers that have fired and move them
  * off the tsk->*_timers list onto the firing list.  Per-thread timers
@@ -1090,10 +1127,10 @@ static void check_process_timers(struct task_struct *tsk,
 	 * Don't sample the current process CPU clocks if there are no timers.
 	 */
 	if (list_empty(&timers[CPUCLOCK_PROF]) &&
-	    cputime_eq(sig->it_prof_expires, cputime_zero) &&
+	    cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) &&
 	    sig->rlim[RLIMIT_CPU].rlim_cur == RLIM_INFINITY &&
 	    list_empty(&timers[CPUCLOCK_VIRT]) &&
-	    cputime_eq(sig->it_virt_expires, cputime_zero) &&
+	    cputime_eq(sig->it[CPUCLOCK_VIRT].expires, cputime_zero) &&
 	    list_empty(&timers[CPUCLOCK_SCHED])) {
 		stop_process_timers(tsk);
 		return;
@@ -1153,38 +1190,11 @@ static void check_process_timers(struct task_struct *tsk,
 	/*
 	 * Check for the special case process timers.
 	 */
-	if (!cputime_eq(sig->it_prof_expires, cputime_zero)) {
-		if (cputime_ge(ptime, sig->it_prof_expires)) {
-			/* ITIMER_PROF fires and reloads.  */
-			sig->it_prof_expires = sig->it_prof_incr;
-			if (!cputime_eq(sig->it_prof_expires, cputime_zero)) {
-				sig->it_prof_expires = cputime_add(
-					sig->it_prof_expires, ptime);
-			}
-			__group_send_sig_info(SIGPROF, SEND_SIG_PRIV, tsk);
-		}
-		if (!cputime_eq(sig->it_prof_expires, cputime_zero) &&
-		    (cputime_eq(prof_expires, cputime_zero) ||
-		     cputime_lt(sig->it_prof_expires, prof_expires))) {
-			prof_expires = sig->it_prof_expires;
-		}
-	}
-	if (!cputime_eq(sig->it_virt_expires, cputime_zero)) {
-		if (cputime_ge(utime, sig->it_virt_expires)) {
-			/* ITIMER_VIRTUAL fires and reloads.  */
-			sig->it_virt_expires = sig->it_virt_incr;
-			if (!cputime_eq(sig->it_virt_expires, cputime_zero)) {
-				sig->it_virt_expires = cputime_add(
-					sig->it_virt_expires, utime);
-			}
-			__group_send_sig_info(SIGVTALRM, SEND_SIG_PRIV, tsk);
-		}
-		if (!cputime_eq(sig->it_virt_expires, cputime_zero) &&
-		    (cputime_eq(virt_expires, cputime_zero) ||
-		     cputime_lt(sig->it_virt_expires, virt_expires))) {
-			virt_expires = sig->it_virt_expires;
-		}
-	}
+	check_cpu_itimer(tsk, &sig->it[CPUCLOCK_PROF], &prof_expires, ptime,
+			 SIGPROF);
+	check_cpu_itimer(tsk, &sig->it[CPUCLOCK_VIRT], &virt_expires, utime,
+			 SIGVTALRM);
+
 	if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
 		unsigned long psecs = cputime_to_secs(ptime);
 		cputime_t x;
@@ -1457,7 +1467,7 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx,
 		if (!cputime_eq(*oldval, cputime_zero)) {
 			if (cputime_le(*oldval, now.cpu)) {
 				/* Just about to fire. */
-				*oldval = jiffies_to_cputime(1);
+				*oldval = cputime_one_jiffy;
 			} else {
 				*oldval = cputime_sub(*oldval, now.cpu);
 			}
@@ -1703,10 +1713,15 @@ static __init int init_posix_cpu_timers(void)
 		.nsleep = thread_cpu_nsleep,
 		.nsleep_restart = thread_cpu_nsleep_restart,
 	};
+	struct timespec ts;
 
 	register_posix_clock(CLOCK_PROCESS_CPUTIME_ID, &process);
 	register_posix_clock(CLOCK_THREAD_CPUTIME_ID, &thread);
 
+	cputime_to_timespec(cputime_one_jiffy, &ts);
+	onecputick = ts.tv_nsec;
+	WARN_ON(ts.tv_sec != 0);
+
 	return 0;
 }
 __initcall(init_posix_cpu_timers);
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index d089d05..4954407 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -242,6 +242,25 @@ static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec *tp)
 	return 0;
 }
 
+
+static int posix_get_realtime_coarse(clockid_t which_clock, struct timespec *tp)
+{
+	*tp = current_kernel_time();
+	return 0;
+}
+
+static int posix_get_monotonic_coarse(clockid_t which_clock,
+						struct timespec *tp)
+{
+	*tp = get_monotonic_coarse();
+	return 0;
+}
+
+int posix_get_coarse_res(const clockid_t which_clock, struct timespec *tp)
+{
+	*tp = ktime_to_timespec(KTIME_LOW_RES);
+	return 0;
+}
 /*
  * Initialize everything, well, just everything in Posix clocks/timers ;)
  */
@@ -262,10 +281,26 @@ static __init int init_posix_timers(void)
 		.timer_create = no_timer_create,
 		.nsleep = no_nsleep,
 	};
+	struct k_clock clock_realtime_coarse = {
+		.clock_getres = posix_get_coarse_res,
+		.clock_get = posix_get_realtime_coarse,
+		.clock_set = do_posix_clock_nosettime,
+		.timer_create = no_timer_create,
+		.nsleep = no_nsleep,
+	};
+	struct k_clock clock_monotonic_coarse = {
+		.clock_getres = posix_get_coarse_res,
+		.clock_get = posix_get_monotonic_coarse,
+		.clock_set = do_posix_clock_nosettime,
+		.timer_create = no_timer_create,
+		.nsleep = no_nsleep,
+	};
 
 	register_posix_clock(CLOCK_REALTIME, &clock_realtime);
 	register_posix_clock(CLOCK_MONOTONIC, &clock_monotonic);
 	register_posix_clock(CLOCK_MONOTONIC_RAW, &clock_monotonic_raw);
+	register_posix_clock(CLOCK_REALTIME_COARSE, &clock_realtime_coarse);
+	register_posix_clock(CLOCK_MONOTONIC_COARSE, &clock_monotonic_coarse);
 
 	posix_timers_cache = kmem_cache_create("posix_timers_cache",
 					sizeof (struct k_itimer), 0, SLAB_PANIC,
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index 72067cb..91e09d3 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -208,3 +208,17 @@ config APM_EMULATION
 	  random kernel OOPSes or reboots that don't seem to be related to
 	  anything, try disabling/enabling this option (or disabling/enabling
 	  APM in your BIOS).
+
+config PM_RUNTIME
+	bool "Run-time PM core functionality"
+	depends on PM
+	---help---
+	  Enable functionality allowing I/O devices to be put into energy-saving
+	  (low power) states at run time (or autosuspended) after a specified
+	  period of inactivity and woken up in response to a hardware-generated
+	  wake-up event or a driver's request.
+
+	  Hardware support is generally required for this functionality to work
+	  and the bus type drivers of the buses the devices are on are
+	  responsible for the actual handling of the autosuspend requests and
+	  wake-up events.
diff --git a/kernel/power/console.c b/kernel/power/console.c
index a3961b20..5187136 100644
--- a/kernel/power/console.c
+++ b/kernel/power/console.c
@@ -14,56 +14,13 @@
 #define SUSPEND_CONSOLE	(MAX_NR_CONSOLES-1)
 
 static int orig_fgconsole, orig_kmsg;
-static int disable_vt_switch;
-
-/*
- * Normally during a suspend, we allocate a new console and switch to it.
- * When we resume, we switch back to the original console.  This switch
- * can be slow, so on systems where the framebuffer can handle restoration
- * of video registers anyways, there's little point in doing the console
- * switch.  This function allows you to disable it by passing it '0'.
- */
-void pm_set_vt_switch(int do_switch)
-{
-	acquire_console_sem();
-	disable_vt_switch = !do_switch;
-	release_console_sem();
-}
-EXPORT_SYMBOL(pm_set_vt_switch);
 
 int pm_prepare_console(void)
 {
-	acquire_console_sem();
-
-	if (disable_vt_switch) {
-		release_console_sem();
-		return 0;
-	}
-
-	orig_fgconsole = fg_console;
-
-	if (vc_allocate(SUSPEND_CONSOLE)) {
-	  /* we can't have a free VC for now. Too bad,
-	   * we don't want to mess the screen for now. */
-		release_console_sem();
+	orig_fgconsole = vt_move_to_console(SUSPEND_CONSOLE, 1);
+	if (orig_fgconsole < 0)
 		return 1;
-	}
 
-	if (set_console(SUSPEND_CONSOLE)) {
-		/*
-		 * We're unable to switch to the SUSPEND_CONSOLE.
-		 * Let the calling function know so it can decide
-		 * what to do.
-		 */
-		release_console_sem();
-		return 1;
-	}
-	release_console_sem();
-
-	if (vt_waitactive(SUSPEND_CONSOLE)) {
-		pr_debug("Suspend: Can't switch VCs.");
-		return 1;
-	}
 	orig_kmsg = kmsg_redirect;
 	kmsg_redirect = SUSPEND_CONSOLE;
 	return 0;
@@ -71,19 +28,9 @@ int pm_prepare_console(void)
 
 void pm_restore_console(void)
 {
-	acquire_console_sem();
-	if (disable_vt_switch) {
-		release_console_sem();
-		return;
-	}
-	set_console(orig_fgconsole);
-	release_console_sem();
-
-	if (vt_waitactive(orig_fgconsole)) {
-		pr_debug("Resume: Can't switch VCs.");
-		return;
+	if (orig_fgconsole >= 0) {
+		vt_move_to_console(orig_fgconsole, 0);
+		kmsg_redirect = orig_kmsg;
 	}
-
-	kmsg_redirect = orig_kmsg;
 }
 #endif
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 81d2e74..04b3a83 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -298,8 +298,8 @@ int hibernation_snapshot(int platform_mode)
 	if (error)
 		return error;
 
-	/* Free memory before shutting down devices. */
-	error = swsusp_shrink_memory();
+	/* Preallocate image memory before shutting down devices. */
+	error = hibernate_preallocate_memory();
 	if (error)
 		goto Close;
 
@@ -315,6 +315,10 @@ int hibernation_snapshot(int platform_mode)
 	/* Control returns here after successful restore */
 
  Resume_devices:
+	/* We may need to release the preallocated image pages here. */
+	if (error || !in_suspend)
+		swsusp_free();
+
 	dpm_resume_end(in_suspend ?
 		(error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
 	resume_console();
@@ -460,11 +464,11 @@ int hibernation_platform_enter(void)
 
 	error = hibernation_ops->prepare();
 	if (error)
-		goto Platofrm_finish;
+		goto Platform_finish;
 
 	error = disable_nonboot_cpus();
 	if (error)
-		goto Platofrm_finish;
+		goto Platform_finish;
 
 	local_irq_disable();
 	sysdev_suspend(PMSG_HIBERNATE);
@@ -476,7 +480,7 @@ int hibernation_platform_enter(void)
 	 * We don't need to reenable the nonboot CPUs or resume consoles, since
 	 * the system is going to be halted anyway.
 	 */
- Platofrm_finish:
+ Platform_finish:
 	hibernation_ops->finish();
 
 	dpm_suspend_noirq(PMSG_RESTORE);
@@ -578,7 +582,10 @@ int hibernate(void)
 		goto Thaw;
 
 	error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
-	if (in_suspend && !error) {
+	if (error)
+		goto Thaw;
+
+	if (in_suspend) {
 		unsigned int flags = 0;
 
 		if (hibernation_mode == HIBERNATION_PLATFORM)
@@ -590,8 +597,8 @@ int hibernate(void)
 			power_down();
 	} else {
 		pr_debug("PM: Image restored successfully.\n");
-		swsusp_free();
 	}
+
  Thaw:
 	thaw_processes();
  Finish:
diff --git a/kernel/power/main.c b/kernel/power/main.c
index f710e36..347d2cc 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -11,6 +11,7 @@
 #include <linux/kobject.h>
 #include <linux/string.h>
 #include <linux/resume-trace.h>
+#include <linux/workqueue.h>
 
 #include "power.h"
 
@@ -217,8 +218,24 @@ static struct attribute_group attr_group = {
 	.attrs = g,
 };
 
+#ifdef CONFIG_PM_RUNTIME
+struct workqueue_struct *pm_wq;
+
+static int __init pm_start_workqueue(void)
+{
+	pm_wq = create_freezeable_workqueue("pm");
+
+	return pm_wq ? 0 : -ENOMEM;
+}
+#else
+static inline int pm_start_workqueue(void) { return 0; }
+#endif
+
 static int __init pm_init(void)
 {
+	int error = pm_start_workqueue();
+	if (error)
+		return error;
 	power_kobj = kobject_create_and_add("power", NULL);
 	if (!power_kobj)
 		return -ENOMEM;
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 26d5a26..46c5a26 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -74,7 +74,7 @@ extern asmlinkage int swsusp_arch_resume(void);
 
 extern int create_basic_memory_bitmaps(void);
 extern void free_basic_memory_bitmaps(void);
-extern int swsusp_shrink_memory(void);
+extern int hibernate_preallocate_memory(void);
 
 /**
  *	Auxiliary structure used for reading the snapshot image data and
diff --git a/kernel/power/process.c b/kernel/power/process.c
index da2072d..cc2e553 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -9,6 +9,7 @@
 #undef DEBUG
 
 #include <linux/interrupt.h>
+#include <linux/oom.h>
 #include <linux/suspend.h>
 #include <linux/module.h>
 #include <linux/syscalls.h>
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 523a451..36cb168 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -233,7 +233,7 @@ static void *chain_alloc(struct chain_allocator *ca, unsigned int size)
 
 #define BM_END_OF_MAP	(~0UL)
 
-#define BM_BITS_PER_BLOCK	(PAGE_SIZE << 3)
+#define BM_BITS_PER_BLOCK	(PAGE_SIZE * BITS_PER_BYTE)
 
 struct bm_block {
 	struct list_head hook;	/* hook into a list of bitmap blocks */
@@ -275,7 +275,7 @@ static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free);
 
 /**
  *	create_bm_block_list - create a list of block bitmap objects
- *	@nr_blocks - number of blocks to allocate
+ *	@pages - number of pages to track
  *	@list - list to put the allocated blocks into
  *	@ca - chain allocator to be used for allocating memory
  */
@@ -619,7 +619,7 @@ __register_nosave_region(unsigned long start_pfn, unsigned long end_pfn,
 		BUG_ON(!region);
 	} else
 		/* This allocation cannot fail */
-		region = alloc_bootmem_low(sizeof(struct nosave_region));
+		region = alloc_bootmem(sizeof(struct nosave_region));
 	region->start_pfn = start_pfn;
 	region->end_pfn = end_pfn;
 	list_add_tail(&region->list, &nosave_regions);
@@ -853,7 +853,7 @@ static unsigned int count_highmem_pages(void)
 	struct zone *zone;
 	unsigned int n = 0;
 
-	for_each_zone(zone) {
+	for_each_populated_zone(zone) {
 		unsigned long pfn, max_zone_pfn;
 
 		if (!is_highmem(zone))
@@ -916,7 +916,7 @@ static unsigned int count_data_pages(void)
 	unsigned long pfn, max_zone_pfn;
 	unsigned int n = 0;
 
-	for_each_zone(zone) {
+	for_each_populated_zone(zone) {
 		if (is_highmem(zone))
 			continue;
 
@@ -1010,7 +1010,7 @@ copy_data_pages(struct memory_bitmap *copy_bm, struct memory_bitmap *orig_bm)
 	struct zone *zone;
 	unsigned long pfn;
 
-	for_each_zone(zone) {
+	for_each_populated_zone(zone) {
 		unsigned long max_zone_pfn;
 
 		mark_free_pages(zone);
@@ -1033,6 +1033,25 @@ copy_data_pages(struct memory_bitmap *copy_bm, struct memory_bitmap *orig_bm)
 static unsigned int nr_copy_pages;
 /* Number of pages needed for saving the original pfns of the image pages */
 static unsigned int nr_meta_pages;
+/*
+ * Numbers of normal and highmem page frames allocated for hibernation image
+ * before suspending devices.
+ */
+unsigned int alloc_normal, alloc_highmem;
+/*
+ * Memory bitmap used for marking saveable pages (during hibernation) or
+ * hibernation image pages (during restore)
+ */
+static struct memory_bitmap orig_bm;
+/*
+ * Memory bitmap used during hibernation for marking allocated page frames that
+ * will contain copies of saveable pages.  During restore it is initially used
+ * for marking hibernation image pages, but then the set bits from it are
+ * duplicated in @orig_bm and it is released.  On highmem systems it is next
+ * used for marking "safe" highmem pages, but it has to be reinitialized for
+ * this purpose.
+ */
+static struct memory_bitmap copy_bm;
 
 /**
  *	swsusp_free - free pages allocated for the suspend.
@@ -1046,7 +1065,7 @@ void swsusp_free(void)
 	struct zone *zone;
 	unsigned long pfn, max_zone_pfn;
 
-	for_each_zone(zone) {
+	for_each_populated_zone(zone) {
 		max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
 		for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
 			if (pfn_valid(pfn)) {
@@ -1064,74 +1083,286 @@ void swsusp_free(void)
 	nr_meta_pages = 0;
 	restore_pblist = NULL;
 	buffer = NULL;
+	alloc_normal = 0;
+	alloc_highmem = 0;
 }
 
+/* Helper functions used for the shrinking of memory. */
+
+#define GFP_IMAGE	(GFP_KERNEL | __GFP_NOWARN)
+
 /**
- *	swsusp_shrink_memory -  Try to free as much memory as needed
- *
- *	... but do not OOM-kill anyone
+ * preallocate_image_pages - Allocate a number of pages for hibernation image
+ * @nr_pages: Number of page frames to allocate.
+ * @mask: GFP flags to use for the allocation.
  *
- *	Notice: all userland should be stopped before it is called, or
- *	livelock is possible.
+ * Return value: Number of page frames actually allocated
+ */
+static unsigned long preallocate_image_pages(unsigned long nr_pages, gfp_t mask)
+{
+	unsigned long nr_alloc = 0;
+
+	while (nr_pages > 0) {
+		struct page *page;
+
+		page = alloc_image_page(mask);
+		if (!page)
+			break;
+		memory_bm_set_bit(&copy_bm, page_to_pfn(page));
+		if (PageHighMem(page))
+			alloc_highmem++;
+		else
+			alloc_normal++;
+		nr_pages--;
+		nr_alloc++;
+	}
+
+	return nr_alloc;
+}
+
+static unsigned long preallocate_image_memory(unsigned long nr_pages)
+{
+	return preallocate_image_pages(nr_pages, GFP_IMAGE);
+}
+
+#ifdef CONFIG_HIGHMEM
+static unsigned long preallocate_image_highmem(unsigned long nr_pages)
+{
+	return preallocate_image_pages(nr_pages, GFP_IMAGE | __GFP_HIGHMEM);
+}
+
+/**
+ *  __fraction - Compute (an approximation of) x * (multiplier / base)
  */
+static unsigned long __fraction(u64 x, u64 multiplier, u64 base)
+{
+	x *= multiplier;
+	do_div(x, base);
+	return (unsigned long)x;
+}
+
+static unsigned long preallocate_highmem_fraction(unsigned long nr_pages,
+						unsigned long highmem,
+						unsigned long total)
+{
+	unsigned long alloc = __fraction(nr_pages, highmem, total);
 
-#define SHRINK_BITE	10000
-static inline unsigned long __shrink_memory(long tmp)
+	return preallocate_image_pages(alloc, GFP_IMAGE | __GFP_HIGHMEM);
+}
+#else /* CONFIG_HIGHMEM */
+static inline unsigned long preallocate_image_highmem(unsigned long nr_pages)
 {
-	if (tmp > SHRINK_BITE)
-		tmp = SHRINK_BITE;
-	return shrink_all_memory(tmp);
+	return 0;
 }
 
-int swsusp_shrink_memory(void)
+static inline unsigned long preallocate_highmem_fraction(unsigned long nr_pages,
+						unsigned long highmem,
+						unsigned long total)
+{
+	return 0;
+}
+#endif /* CONFIG_HIGHMEM */
+
+/**
+ * free_unnecessary_pages - Release preallocated pages not needed for the image
+ */
+static void free_unnecessary_pages(void)
+{
+	unsigned long save_highmem, to_free_normal, to_free_highmem;
+
+	to_free_normal = alloc_normal - count_data_pages();
+	save_highmem = count_highmem_pages();
+	if (alloc_highmem > save_highmem) {
+		to_free_highmem = alloc_highmem - save_highmem;
+	} else {
+		to_free_highmem = 0;
+		to_free_normal -= save_highmem - alloc_highmem;
+	}
+
+	memory_bm_position_reset(&copy_bm);
+
+	while (to_free_normal > 0 && to_free_highmem > 0) {
+		unsigned long pfn = memory_bm_next_pfn(&copy_bm);
+		struct page *page = pfn_to_page(pfn);
+
+		if (PageHighMem(page)) {
+			if (!to_free_highmem)
+				continue;
+			to_free_highmem--;
+			alloc_highmem--;
+		} else {
+			if (!to_free_normal)
+				continue;
+			to_free_normal--;
+			alloc_normal--;
+		}
+		memory_bm_clear_bit(&copy_bm, pfn);
+		swsusp_unset_page_forbidden(page);
+		swsusp_unset_page_free(page);
+		__free_page(page);
+	}
+}
+
+/**
+ * minimum_image_size - Estimate the minimum acceptable size of an image
+ * @saveable: Number of saveable pages in the system.
+ *
+ * We want to avoid attempting to free too much memory too hard, so estimate the
+ * minimum acceptable size of a hibernation image to use as the lower limit for
+ * preallocating memory.
+ *
+ * We assume that the minimum image size should be proportional to
+ *
+ * [number of saveable pages] - [number of pages that can be freed in theory]
+ *
+ * where the second term is the sum of (1) reclaimable slab pages, (2) active
+ * and (3) inactive anonymouns pages, (4) active and (5) inactive file pages,
+ * minus mapped file pages.
+ */
+static unsigned long minimum_image_size(unsigned long saveable)
+{
+	unsigned long size;
+
+	size = global_page_state(NR_SLAB_RECLAIMABLE)
+		+ global_page_state(NR_ACTIVE_ANON)
+		+ global_page_state(NR_INACTIVE_ANON)
+		+ global_page_state(NR_ACTIVE_FILE)
+		+ global_page_state(NR_INACTIVE_FILE)
+		- global_page_state(NR_FILE_MAPPED);
+
+	return saveable <= size ? 0 : saveable - size;
+}
+
+/**
+ * hibernate_preallocate_memory - Preallocate memory for hibernation image
+ *
+ * To create a hibernation image it is necessary to make a copy of every page
+ * frame in use.  We also need a number of page frames to be free during
+ * hibernation for allocations made while saving the image and for device
+ * drivers, in case they need to allocate memory from their hibernation
+ * callbacks (these two numbers are given by PAGES_FOR_IO and SPARE_PAGES,
+ * respectively, both of which are rough estimates).  To make this happen, we
+ * compute the total number of available page frames and allocate at least
+ *
+ * ([page frames total] + PAGES_FOR_IO + [metadata pages]) / 2 + 2 * SPARE_PAGES
+ *
+ * of them, which corresponds to the maximum size of a hibernation image.
+ *
+ * If image_size is set below the number following from the above formula,
+ * the preallocation of memory is continued until the total number of saveable
+ * pages in the system is below the requested image size or the minimum
+ * acceptable image size returned by minimum_image_size(), whichever is greater.
+ */
+int hibernate_preallocate_memory(void)
 {
-	long tmp;
 	struct zone *zone;
-	unsigned long pages = 0;
-	unsigned int i = 0;
-	char *p = "-\\|/";
+	unsigned long saveable, size, max_size, count, highmem, pages = 0;
+	unsigned long alloc, save_highmem, pages_highmem;
 	struct timeval start, stop;
+	int error;
 
-	printk(KERN_INFO "PM: Shrinking memory...  ");
+	printk(KERN_INFO "PM: Preallocating image memory... ");
 	do_gettimeofday(&start);
-	do {
-		long size, highmem_size;
-
-		highmem_size = count_highmem_pages();
-		size = count_data_pages() + PAGES_FOR_IO + SPARE_PAGES;
-		tmp = size;
-		size += highmem_size;
-		for_each_populated_zone(zone) {
-			tmp += snapshot_additional_pages(zone);
-			if (is_highmem(zone)) {
-				highmem_size -=
-					zone_page_state(zone, NR_FREE_PAGES);
-			} else {
-				tmp -= zone_page_state(zone, NR_FREE_PAGES);
-				tmp += zone->lowmem_reserve[ZONE_NORMAL];
-			}
-		}
 
-		if (highmem_size < 0)
-			highmem_size = 0;
+	error = memory_bm_create(&orig_bm, GFP_IMAGE, PG_ANY);
+	if (error)
+		goto err_out;
 
-		tmp += highmem_size;
-		if (tmp > 0) {
-			tmp = __shrink_memory(tmp);
-			if (!tmp)
-				return -ENOMEM;
-			pages += tmp;
-		} else if (size > image_size / PAGE_SIZE) {
-			tmp = __shrink_memory(size - (image_size / PAGE_SIZE));
-			pages += tmp;
-		}
-		printk("\b%c", p[i++%4]);
-	} while (tmp > 0);
+	error = memory_bm_create(&copy_bm, GFP_IMAGE, PG_ANY);
+	if (error)
+		goto err_out;
+
+	alloc_normal = 0;
+	alloc_highmem = 0;
+
+	/* Count the number of saveable data pages. */
+	save_highmem = count_highmem_pages();
+	saveable = count_data_pages();
+
+	/*
+	 * Compute the total number of page frames we can use (count) and the
+	 * number of pages needed for image metadata (size).
+	 */
+	count = saveable;
+	saveable += save_highmem;
+	highmem = save_highmem;
+	size = 0;
+	for_each_populated_zone(zone) {
+		size += snapshot_additional_pages(zone);
+		if (is_highmem(zone))
+			highmem += zone_page_state(zone, NR_FREE_PAGES);
+		else
+			count += zone_page_state(zone, NR_FREE_PAGES);
+	}
+	count += highmem;
+	count -= totalreserve_pages;
+
+	/* Compute the maximum number of saveable pages to leave in memory. */
+	max_size = (count - (size + PAGES_FOR_IO)) / 2 - 2 * SPARE_PAGES;
+	size = DIV_ROUND_UP(image_size, PAGE_SIZE);
+	if (size > max_size)
+		size = max_size;
+	/*
+	 * If the maximum is not less than the current number of saveable pages
+	 * in memory, allocate page frames for the image and we're done.
+	 */
+	if (size >= saveable) {
+		pages = preallocate_image_highmem(save_highmem);
+		pages += preallocate_image_memory(saveable - pages);
+		goto out;
+	}
+
+	/* Estimate the minimum size of the image. */
+	pages = minimum_image_size(saveable);
+	if (size < pages)
+		size = min_t(unsigned long, pages, max_size);
+
+	/*
+	 * Let the memory management subsystem know that we're going to need a
+	 * large number of page frames to allocate and make it free some memory.
+	 * NOTE: If this is not done, performance will be hurt badly in some
+	 * test cases.
+	 */
+	shrink_all_memory(saveable - size);
+
+	/*
+	 * The number of saveable pages in memory was too high, so apply some
+	 * pressure to decrease it.  First, make room for the largest possible
+	 * image and fail if that doesn't work.  Next, try to decrease the size
+	 * of the image as much as indicated by 'size' using allocations from
+	 * highmem and non-highmem zones separately.
+	 */
+	pages_highmem = preallocate_image_highmem(highmem / 2);
+	alloc = (count - max_size) - pages_highmem;
+	pages = preallocate_image_memory(alloc);
+	if (pages < alloc)
+		goto err_out;
+	size = max_size - size;
+	alloc = size;
+	size = preallocate_highmem_fraction(size, highmem, count);
+	pages_highmem += size;
+	alloc -= size;
+	pages += preallocate_image_memory(alloc);
+	pages += pages_highmem;
+
+	/*
+	 * We only need as many page frames for the image as there are saveable
+	 * pages in memory, but we have allocated more.  Release the excessive
+	 * ones now.
+	 */
+	free_unnecessary_pages();
+
+ out:
 	do_gettimeofday(&stop);
-	printk("\bdone (%lu pages freed)\n", pages);
-	swsusp_show_speed(&start, &stop, pages, "Freed");
+	printk(KERN_CONT "done (allocated %lu pages)\n", pages);
+	swsusp_show_speed(&start, &stop, pages, "Allocated");
 
 	return 0;
+
+ err_out:
+	printk(KERN_CONT "\n");
+	swsusp_free();
+	return -ENOMEM;
 }
 
 #ifdef CONFIG_HIGHMEM
@@ -1142,7 +1373,7 @@ int swsusp_shrink_memory(void)
 
 static unsigned int count_pages_for_highmem(unsigned int nr_highmem)
 {
-	unsigned int free_highmem = count_free_highmem_pages();
+	unsigned int free_highmem = count_free_highmem_pages() + alloc_highmem;
 
 	if (free_highmem >= nr_highmem)
 		nr_highmem = 0;
@@ -1164,19 +1395,17 @@ count_pages_for_highmem(unsigned int nr_highmem) { return 0; }
 static int enough_free_mem(unsigned int nr_pages, unsigned int nr_highmem)
 {
 	struct zone *zone;
-	unsigned int free = 0, meta = 0;
+	unsigned int free = alloc_normal;
 
-	for_each_zone(zone) {
-		meta += snapshot_additional_pages(zone);
+	for_each_populated_zone(zone)
 		if (!is_highmem(zone))
 			free += zone_page_state(zone, NR_FREE_PAGES);
-	}
 
 	nr_pages += count_pages_for_highmem(nr_highmem);
-	pr_debug("PM: Normal pages needed: %u + %u + %u, available pages: %u\n",
-		nr_pages, PAGES_FOR_IO, meta, free);
+	pr_debug("PM: Normal pages needed: %u + %u, available pages: %u\n",
+		nr_pages, PAGES_FOR_IO, free);
 
-	return free > nr_pages + PAGES_FOR_IO + meta;
+	return free > nr_pages + PAGES_FOR_IO;
 }
 
 #ifdef CONFIG_HIGHMEM
@@ -1198,7 +1427,7 @@ static inline int get_highmem_buffer(int safe_needed)
  */
 
 static inline unsigned int
-alloc_highmem_image_pages(struct memory_bitmap *bm, unsigned int nr_highmem)
+alloc_highmem_pages(struct memory_bitmap *bm, unsigned int nr_highmem)
 {
 	unsigned int to_alloc = count_free_highmem_pages();
 
@@ -1218,7 +1447,7 @@ alloc_highmem_image_pages(struct memory_bitmap *bm, unsigned int nr_highmem)
 static inline int get_highmem_buffer(int safe_needed) { return 0; }
 
 static inline unsigned int
-alloc_highmem_image_pages(struct memory_bitmap *bm, unsigned int n) { return 0; }
+alloc_highmem_pages(struct memory_bitmap *bm, unsigned int n) { return 0; }
 #endif /* CONFIG_HIGHMEM */
 
 /**
@@ -1237,51 +1466,36 @@ static int
 swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm,
 		unsigned int nr_pages, unsigned int nr_highmem)
 {
-	int error;
-
-	error = memory_bm_create(orig_bm, GFP_ATOMIC | __GFP_COLD, PG_ANY);
-	if (error)
-		goto Free;
-
-	error = memory_bm_create(copy_bm, GFP_ATOMIC | __GFP_COLD, PG_ANY);
-	if (error)
-		goto Free;
+	int error = 0;
 
 	if (nr_highmem > 0) {
 		error = get_highmem_buffer(PG_ANY);
 		if (error)
-			goto Free;
-
-		nr_pages += alloc_highmem_image_pages(copy_bm, nr_highmem);
+			goto err_out;
+		if (nr_highmem > alloc_highmem) {
+			nr_highmem -= alloc_highmem;
+			nr_pages += alloc_highmem_pages(copy_bm, nr_highmem);
+		}
 	}
-	while (nr_pages-- > 0) {
-		struct page *page = alloc_image_page(GFP_ATOMIC | __GFP_COLD);
-
-		if (!page)
-			goto Free;
+	if (nr_pages > alloc_normal) {
+		nr_pages -= alloc_normal;
+		while (nr_pages-- > 0) {
+			struct page *page;
 
-		memory_bm_set_bit(copy_bm, page_to_pfn(page));
+			page = alloc_image_page(GFP_ATOMIC | __GFP_COLD);
+			if (!page)
+				goto err_out;
+			memory_bm_set_bit(copy_bm, page_to_pfn(page));
+		}
 	}
+
 	return 0;
 
- Free:
+ err_out:
 	swsusp_free();
-	return -ENOMEM;
+	return error;
 }
 
-/* Memory bitmap used for marking saveable pages (during suspend) or the
- * suspend image pages (during resume)
- */
-static struct memory_bitmap orig_bm;
-/* Memory bitmap used on suspend for marking allocated pages that will contain
- * the copies of saveable pages.  During resume it is initially used for
- * marking the suspend image pages, but then its set bits are duplicated in
- * @orig_bm and it is released.  Next, on systems with high memory, it may be
- * used for marking "safe" highmem pages, but it has to be reinitialized for
- * this purpose.
- */
-static struct memory_bitmap copy_bm;
-
 asmlinkage int swsusp_save(void)
 {
 	unsigned int nr_pages, nr_highmem;
@@ -1474,7 +1688,7 @@ static int mark_unsafe_pages(struct memory_bitmap *bm)
 	unsigned long pfn, max_zone_pfn;
 
 	/* Clear page flags */
-	for_each_zone(zone) {
+	for_each_populated_zone(zone) {
 		max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
 		for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
 			if (pfn_valid(pfn))
diff --git a/kernel/printk.c b/kernel/printk.c
index b4d97b5..f38b07f 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -37,6 +37,12 @@
 #include <asm/uaccess.h>
 
 /*
+ * for_each_console() allows you to iterate on each console
+ */
+#define for_each_console(con) \
+	for (con = console_drivers; con != NULL; con = con->next)
+
+/*
  * Architectures can override it:
  */
 void asmlinkage __attribute__((weak)) early_printk(const char *fmt, ...)
@@ -61,6 +67,8 @@ int console_printk[4] = {
 	DEFAULT_CONSOLE_LOGLEVEL,	/* default_console_loglevel */
 };
 
+static int saved_console_loglevel = -1;
+
 /*
  * Low level drivers may need that to know if they can schedule in
  * their unblank() callback or not. So let's export it.
@@ -198,12 +206,11 @@ __setup("log_buf_len=", log_buf_len_setup);
 #ifdef CONFIG_BOOT_PRINTK_DELAY
 
 static unsigned int boot_delay; /* msecs delay after each printk during bootup */
-static unsigned long long printk_delay_msec; /* per msec, based on boot_delay */
+static unsigned long long loops_per_msec;	/* based on boot_delay */
 
 static int __init boot_delay_setup(char *str)
 {
 	unsigned long lpj;
-	unsigned long long loops_per_msec;
 
 	lpj = preset_lpj ? preset_lpj : 1000000;	/* some guess */
 	loops_per_msec = (unsigned long long)lpj / 1000 * HZ;
@@ -212,10 +219,9 @@ static int __init boot_delay_setup(char *str)
 	if (boot_delay > 10 * 1000)
 		boot_delay = 0;
 
-	printk_delay_msec = loops_per_msec;
-	printk(KERN_DEBUG "boot_delay: %u, preset_lpj: %ld, lpj: %lu, "
-		"HZ: %d, printk_delay_msec: %llu\n",
-		boot_delay, preset_lpj, lpj, HZ, printk_delay_msec);
+	pr_debug("boot_delay: %u, preset_lpj: %ld, lpj: %lu, "
+		"HZ: %d, loops_per_msec: %llu\n",
+		boot_delay, preset_lpj, lpj, HZ, loops_per_msec);
 	return 1;
 }
 __setup("boot_delay=", boot_delay_setup);
@@ -228,7 +234,7 @@ static void boot_delay_msec(void)
 	if (boot_delay == 0 || system_state != SYSTEM_BOOTING)
 		return;
 
-	k = (unsigned long long)printk_delay_msec * boot_delay;
+	k = (unsigned long long)loops_per_msec * boot_delay;
 
 	timeout = jiffies + msecs_to_jiffies(boot_delay);
 	while (k) {
@@ -372,10 +378,15 @@ int do_syslog(int type, char __user *buf, int len)
 		logged_chars = 0;
 		break;
 	case 6:		/* Disable logging to console */
+		if (saved_console_loglevel == -1)
+			saved_console_loglevel = console_loglevel;
 		console_loglevel = minimum_console_loglevel;
 		break;
 	case 7:		/* Enable logging to console */
-		console_loglevel = default_console_loglevel;
+		if (saved_console_loglevel != -1) {
+			console_loglevel = saved_console_loglevel;
+			saved_console_loglevel = -1;
+		}
 		break;
 	case 8:		/* Set level of messages printed to console */
 		error = -EINVAL;
@@ -384,6 +395,8 @@ int do_syslog(int type, char __user *buf, int len)
 		if (len < minimum_console_loglevel)
 			len = minimum_console_loglevel;
 		console_loglevel = len;
+		/* Implicitly re-enable logging to console */
+		saved_console_loglevel = -1;
 		error = 0;
 		break;
 	case 9:		/* Number of chars in the log buffer */
@@ -412,7 +425,7 @@ static void __call_console_drivers(unsigned start, unsigned end)
 {
 	struct console *con;
 
-	for (con = console_drivers; con; con = con->next) {
+	for_each_console(con) {
 		if ((con->flags & CON_ENABLED) && con->write &&
 				(cpu_online(smp_processor_id()) ||
 				(con->flags & CON_ANYTIME)))
@@ -544,7 +557,7 @@ static int have_callable_console(void)
 {
 	struct console *con;
 
-	for (con = console_drivers; con; con = con->next)
+	for_each_console(con)
 		if (con->flags & CON_ANYTIME)
 			return 1;
 
@@ -640,6 +653,20 @@ static int recursion_bug;
 static int new_text_line = 1;
 static char printk_buf[1024];
 
+int printk_delay_msec __read_mostly;
+
+static inline void printk_delay(void)
+{
+	if (unlikely(printk_delay_msec)) {
+		int m = printk_delay_msec;
+
+		while (m--) {
+			mdelay(1);
+			touch_nmi_watchdog();
+		}
+	}
+}
+
 asmlinkage int vprintk(const char *fmt, va_list args)
 {
 	int printed_len = 0;
@@ -649,6 +676,7 @@ asmlinkage int vprintk(const char *fmt, va_list args)
 	char *p;
 
 	boot_delay_msec();
+	printk_delay();
 
 	preempt_disable();
 	/* This stops the holder of console_sem just where we want him */
@@ -1060,12 +1088,6 @@ void __sched console_conditional_schedule(void)
 }
 EXPORT_SYMBOL(console_conditional_schedule);
 
-void console_print(const char *s)
-{
-	printk(KERN_EMERG "%s", s);
-}
-EXPORT_SYMBOL(console_print);
-
 void console_unblank(void)
 {
 	struct console *c;
@@ -1082,7 +1104,7 @@ void console_unblank(void)
 
 	console_locked = 1;
 	console_may_schedule = 0;
-	for (c = console_drivers; c != NULL; c = c->next)
+	for_each_console(c)
 		if ((c->flags & CON_ENABLED) && c->unblank)
 			c->unblank();
 	release_console_sem();
@@ -1097,7 +1119,7 @@ struct tty_driver *console_device(int *index)
 	struct tty_driver *driver = NULL;
 
 	acquire_console_sem();
-	for (c = console_drivers; c != NULL; c = c->next) {
+	for_each_console(c) {
 		if (!c->device)
 			continue;
 		driver = c->device(c, index);
@@ -1134,25 +1156,49 @@ EXPORT_SYMBOL(console_start);
  * to register the console printing procedure with printk() and to
  * print any messages that were printed by the kernel before the
  * console driver was initialized.
+ *
+ * This can happen pretty early during the boot process (because of
+ * early_printk) - sometimes before setup_arch() completes - be careful
+ * of what kernel features are used - they may not be initialised yet.
+ *
+ * There are two types of consoles - bootconsoles (early_printk) and
+ * "real" consoles (everything which is not a bootconsole) which are
+ * handled differently.
+ *  - Any number of bootconsoles can be registered at any time.
+ *  - As soon as a "real" console is registered, all bootconsoles
+ *    will be unregistered automatically.
+ *  - Once a "real" console is registered, any attempt to register a
+ *    bootconsoles will be rejected
  */
-void register_console(struct console *console)
+void register_console(struct console *newcon)
 {
 	int i;
 	unsigned long flags;
-	struct console *bootconsole = NULL;
+	struct console *bcon = NULL;
 
-	if (console_drivers) {
-		if (console->flags & CON_BOOT)
-			return;
-		if (console_drivers->flags & CON_BOOT)
-			bootconsole = console_drivers;
+	/*
+	 * before we register a new CON_BOOT console, make sure we don't
+	 * already have a valid console
+	 */
+	if (console_drivers && newcon->flags & CON_BOOT) {
+		/* find the last or real console */
+		for_each_console(bcon) {
+			if (!(bcon->flags & CON_BOOT)) {
+				printk(KERN_INFO "Too late to register bootconsole %s%d\n",
+					newcon->name, newcon->index);
+				return;
+			}
+		}
 	}
 
-	if (preferred_console < 0 || bootconsole || !console_drivers)
+	if (console_drivers && console_drivers->flags & CON_BOOT)
+		bcon = console_drivers;
+
+	if (preferred_console < 0 || bcon || !console_drivers)
 		preferred_console = selected_console;
 
-	if (console->early_setup)
-		console->early_setup();
+	if (newcon->early_setup)
+		newcon->early_setup();
 
 	/*
 	 *	See if we want to use this console driver. If we
@@ -1160,13 +1206,13 @@ void register_console(struct console *console)
 	 *	that registers here.
 	 */
 	if (preferred_console < 0) {
-		if (console->index < 0)
-			console->index = 0;
-		if (console->setup == NULL ||
-		    console->setup(console, NULL) == 0) {
-			console->flags |= CON_ENABLED;
-			if (console->device) {
-				console->flags |= CON_CONSDEV;
+		if (newcon->index < 0)
+			newcon->index = 0;
+		if (newcon->setup == NULL ||
+		    newcon->setup(newcon, NULL) == 0) {
+			newcon->flags |= CON_ENABLED;
+			if (newcon->device) {
+				newcon->flags |= CON_CONSDEV;
 				preferred_console = 0;
 			}
 		}
@@ -1178,64 +1224,62 @@ void register_console(struct console *console)
 	 */
 	for (i = 0; i < MAX_CMDLINECONSOLES && console_cmdline[i].name[0];
 			i++) {
-		if (strcmp(console_cmdline[i].name, console->name) != 0)
+		if (strcmp(console_cmdline[i].name, newcon->name) != 0)
 			continue;
-		if (console->index >= 0 &&
-		    console->index != console_cmdline[i].index)
+		if (newcon->index >= 0 &&
+		    newcon->index != console_cmdline[i].index)
 			continue;
-		if (console->index < 0)
-			console->index = console_cmdline[i].index;
+		if (newcon->index < 0)
+			newcon->index = console_cmdline[i].index;
 #ifdef CONFIG_A11Y_BRAILLE_CONSOLE
 		if (console_cmdline[i].brl_options) {
-			console->flags |= CON_BRL;
-			braille_register_console(console,
+			newcon->flags |= CON_BRL;
+			braille_register_console(newcon,
 					console_cmdline[i].index,
 					console_cmdline[i].options,
 					console_cmdline[i].brl_options);
 			return;
 		}
 #endif
-		if (console->setup &&
-		    console->setup(console, console_cmdline[i].options) != 0)
+		if (newcon->setup &&
+		    newcon->setup(newcon, console_cmdline[i].options) != 0)
 			break;
-		console->flags |= CON_ENABLED;
-		console->index = console_cmdline[i].index;
+		newcon->flags |= CON_ENABLED;
+		newcon->index = console_cmdline[i].index;
 		if (i == selected_console) {
-			console->flags |= CON_CONSDEV;
+			newcon->flags |= CON_CONSDEV;
 			preferred_console = selected_console;
 		}
 		break;
 	}
 
-	if (!(console->flags & CON_ENABLED))
+	if (!(newcon->flags & CON_ENABLED))
 		return;
 
-	if (bootconsole && (console->flags & CON_CONSDEV)) {
-		printk(KERN_INFO "console handover: boot [%s%d] -> real [%s%d]\n",
-		       bootconsole->name, bootconsole->index,
-		       console->name, console->index);
-		unregister_console(bootconsole);
-		console->flags &= ~CON_PRINTBUFFER;
-	} else {
-		printk(KERN_INFO "console [%s%d] enabled\n",
-		       console->name, console->index);
-	}
+	/*
+	 * If we have a bootconsole, and are switching to a real console,
+	 * don't print everything out again, since when the boot console, and
+	 * the real console are the same physical device, it's annoying to
+	 * see the beginning boot messages twice
+	 */
+	if (bcon && ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV))
+		newcon->flags &= ~CON_PRINTBUFFER;
 
 	/*
 	 *	Put this console in the list - keep the
 	 *	preferred driver at the head of the list.
 	 */
 	acquire_console_sem();
-	if ((console->flags & CON_CONSDEV) || console_drivers == NULL) {
-		console->next = console_drivers;
-		console_drivers = console;
-		if (console->next)
-			console->next->flags &= ~CON_CONSDEV;
+	if ((newcon->flags & CON_CONSDEV) || console_drivers == NULL) {
+		newcon->next = console_drivers;
+		console_drivers = newcon;
+		if (newcon->next)
+			newcon->next->flags &= ~CON_CONSDEV;
 	} else {
-		console->next = console_drivers->next;
-		console_drivers->next = console;
+		newcon->next = console_drivers->next;
+		console_drivers->next = newcon;
 	}
-	if (console->flags & CON_PRINTBUFFER) {
+	if (newcon->flags & CON_PRINTBUFFER) {
 		/*
 		 * release_console_sem() will print out the buffered messages
 		 * for us.
@@ -1245,6 +1289,28 @@ void register_console(struct console *console)
 		spin_unlock_irqrestore(&logbuf_lock, flags);
 	}
 	release_console_sem();
+
+	/*
+	 * By unregistering the bootconsoles after we enable the real console
+	 * we get the "console xxx enabled" message on all the consoles -
+	 * boot consoles, real consoles, etc - this is to ensure that end
+	 * users know there might be something in the kernel's log buffer that
+	 * went to the bootconsole (that they do not see on the real console)
+	 */
+	if (bcon && ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV)) {
+		/* we need to iterate through twice, to make sure we print
+		 * everything out, before we unregister the console(s)
+		 */
+		printk(KERN_INFO "console [%s%d] enabled, bootconsole disabled\n",
+			newcon->name, newcon->index);
+		for_each_console(bcon)
+			if (bcon->flags & CON_BOOT)
+				unregister_console(bcon);
+	} else {
+		printk(KERN_INFO "%sconsole [%s%d] enabled\n",
+			(newcon->flags & CON_BOOT) ? "boot" : "" ,
+			newcon->name, newcon->index);
+	}
 }
 EXPORT_SYMBOL(register_console);
 
@@ -1287,11 +1353,13 @@ EXPORT_SYMBOL(unregister_console);
 
 static int __init disable_boot_consoles(void)
 {
-	if (console_drivers != NULL) {
-		if (console_drivers->flags & CON_BOOT) {
+	struct console *con;
+
+	for_each_console(con) {
+		if (con->flags & CON_BOOT) {
 			printk(KERN_INFO "turn off boot console %s%d\n",
-				console_drivers->name, console_drivers->index);
-			return unregister_console(console_drivers);
+				con->name, con->index);
+			unregister_console(con);
 		}
 	}
 	return 0;
diff --git a/kernel/profile.c b/kernel/profile.c
index 419250e..a55d3a3 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -442,48 +442,51 @@ void profile_tick(int type)
 
 #ifdef CONFIG_PROC_FS
 #include <linux/proc_fs.h>
+#include <linux/seq_file.h>
 #include <asm/uaccess.h>
 
-static int prof_cpu_mask_read_proc(char *page, char **start, off_t off,
-			int count, int *eof, void *data)
+static int prof_cpu_mask_proc_show(struct seq_file *m, void *v)
 {
-	int len = cpumask_scnprintf(page, count, data);
-	if (count - len < 2)
-		return -EINVAL;
-	len += sprintf(page + len, "\n");
-	return len;
+	seq_cpumask(m, prof_cpu_mask);
+	seq_putc(m, '\n');
+	return 0;
 }
 
-static int prof_cpu_mask_write_proc(struct file *file,
-	const char __user *buffer,  unsigned long count, void *data)
+static int prof_cpu_mask_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, prof_cpu_mask_proc_show, NULL);
+}
+
+static ssize_t prof_cpu_mask_proc_write(struct file *file,
+	const char __user *buffer, size_t count, loff_t *pos)
 {
-	struct cpumask *mask = data;
-	unsigned long full_count = count, err;
 	cpumask_var_t new_value;
+	int err;
 
 	if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
 		return -ENOMEM;
 
 	err = cpumask_parse_user(buffer, count, new_value);
 	if (!err) {
-		cpumask_copy(mask, new_value);
-		err = full_count;
+		cpumask_copy(prof_cpu_mask, new_value);
+		err = count;
 	}
 	free_cpumask_var(new_value);
 	return err;
 }
 
+static const struct file_operations prof_cpu_mask_proc_fops = {
+	.open		= prof_cpu_mask_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+	.write		= prof_cpu_mask_proc_write,
+};
+
 void create_prof_cpu_mask(struct proc_dir_entry *root_irq_dir)
 {
-	struct proc_dir_entry *entry;
-
 	/* create /proc/irq/prof_cpu_mask */
-	entry = create_proc_entry("prof_cpu_mask", 0600, root_irq_dir);
-	if (!entry)
-		return;
-	entry->data = prof_cpu_mask;
-	entry->read_proc = prof_cpu_mask_read_proc;
-	entry->write_proc = prof_cpu_mask_write_proc;
+	proc_create("prof_cpu_mask", 0600, root_irq_dir, &prof_cpu_mask_proc_fops);
 }
 
 /*
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 082c320..307c285 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -152,7 +152,7 @@ int __ptrace_may_access(struct task_struct *task, unsigned int mode)
 	if (!dumpable && !capable(CAP_SYS_PTRACE))
 		return -EPERM;
 
-	return security_ptrace_may_access(task, mode);
+	return security_ptrace_access_check(task, mode);
 }
 
 bool ptrace_may_access(struct task_struct *task, unsigned int mode)
diff --git a/kernel/rcuclassic.c b/kernel/rcuclassic.c
deleted file mode 100644
index 0f2b0b3..0000000
--- a/kernel/rcuclassic.c
+++ /dev/null
@@ -1,807 +0,0 @@
-/*
- * Read-Copy Update mechanism for mutual exclusion
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
- * Copyright IBM Corporation, 2001
- *
- * Authors: Dipankar Sarma <dipankar@in.ibm.com>
- *	    Manfred Spraul <manfred@colorfullife.com>
- *
- * Based on the original work by Paul McKenney <paulmck@us.ibm.com>
- * and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen.
- * Papers:
- * http://www.rdrop.com/users/paulmck/paper/rclockpdcsproof.pdf
- * http://lse.sourceforge.net/locking/rclock_OLS.2001.05.01c.sc.pdf (OLS2001)
- *
- * For detailed explanation of Read-Copy Update mechanism see -
- * 		Documentation/RCU
- *
- */
-#include <linux/types.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/spinlock.h>
-#include <linux/smp.h>
-#include <linux/rcupdate.h>
-#include <linux/interrupt.h>
-#include <linux/sched.h>
-#include <asm/atomic.h>
-#include <linux/bitops.h>
-#include <linux/module.h>
-#include <linux/completion.h>
-#include <linux/moduleparam.h>
-#include <linux/percpu.h>
-#include <linux/notifier.h>
-#include <linux/cpu.h>
-#include <linux/mutex.h>
-#include <linux/time.h>
-
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-static struct lock_class_key rcu_lock_key;
-struct lockdep_map rcu_lock_map =
-	STATIC_LOCKDEP_MAP_INIT("rcu_read_lock", &rcu_lock_key);
-EXPORT_SYMBOL_GPL(rcu_lock_map);
-#endif
-
-
-/* Definition for rcupdate control block. */
-static struct rcu_ctrlblk rcu_ctrlblk = {
-	.cur = -300,
-	.completed = -300,
-	.pending = -300,
-	.lock = __SPIN_LOCK_UNLOCKED(&rcu_ctrlblk.lock),
-	.cpumask = CPU_BITS_NONE,
-};
-
-static struct rcu_ctrlblk rcu_bh_ctrlblk = {
-	.cur = -300,
-	.completed = -300,
-	.pending = -300,
-	.lock = __SPIN_LOCK_UNLOCKED(&rcu_bh_ctrlblk.lock),
-	.cpumask = CPU_BITS_NONE,
-};
-
-static DEFINE_PER_CPU(struct rcu_data, rcu_data);
-static DEFINE_PER_CPU(struct rcu_data, rcu_bh_data);
-
-/*
- * Increment the quiescent state counter.
- * The counter is a bit degenerated: We do not need to know
- * how many quiescent states passed, just if there was at least
- * one since the start of the grace period. Thus just a flag.
- */
-void rcu_qsctr_inc(int cpu)
-{
-	struct rcu_data *rdp = &per_cpu(rcu_data, cpu);
-	rdp->passed_quiesc = 1;
-}
-
-void rcu_bh_qsctr_inc(int cpu)
-{
-	struct rcu_data *rdp = &per_cpu(rcu_bh_data, cpu);
-	rdp->passed_quiesc = 1;
-}
-
-static int blimit = 10;
-static int qhimark = 10000;
-static int qlowmark = 100;
-
-#ifdef CONFIG_SMP
-static void force_quiescent_state(struct rcu_data *rdp,
-			struct rcu_ctrlblk *rcp)
-{
-	int cpu;
-	unsigned long flags;
-
-	set_need_resched();
-	spin_lock_irqsave(&rcp->lock, flags);
-	if (unlikely(!rcp->signaled)) {
-		rcp->signaled = 1;
-		/*
-		 * Don't send IPI to itself. With irqs disabled,
-		 * rdp->cpu is the current cpu.
-		 *
-		 * cpu_online_mask is updated by the _cpu_down()
-		 * using __stop_machine(). Since we're in irqs disabled
-		 * section, __stop_machine() is not exectuting, hence
-		 * the cpu_online_mask is stable.
-		 *
-		 * However,  a cpu might have been offlined _just_ before
-		 * we disabled irqs while entering here.
-		 * And rcu subsystem might not yet have handled the CPU_DEAD
-		 * notification, leading to the offlined cpu's bit
-		 * being set in the rcp->cpumask.
-		 *
-		 * Hence cpumask = (rcp->cpumask & cpu_online_mask) to prevent
-		 * sending smp_reschedule() to an offlined CPU.
-		 */
-		for_each_cpu_and(cpu,
-				  to_cpumask(rcp->cpumask), cpu_online_mask) {
-			if (cpu != rdp->cpu)
-				smp_send_reschedule(cpu);
-		}
-	}
-	spin_unlock_irqrestore(&rcp->lock, flags);
-}
-#else
-static inline void force_quiescent_state(struct rcu_data *rdp,
-			struct rcu_ctrlblk *rcp)
-{
-	set_need_resched();
-}
-#endif
-
-static void __call_rcu(struct rcu_head *head, struct rcu_ctrlblk *rcp,
-		struct rcu_data *rdp)
-{
-	long batch;
-
-	head->next = NULL;
-	smp_mb(); /* Read of rcu->cur must happen after any change by caller. */
-
-	/*
-	 * Determine the batch number of this callback.
-	 *
-	 * Using ACCESS_ONCE to avoid the following error when gcc eliminates
-	 * local variable "batch" and emits codes like this:
-	 *	1) rdp->batch = rcp->cur + 1 # gets old value
-	 *	......
-	 *	2)rcu_batch_after(rcp->cur + 1, rdp->batch) # gets new value
-	 * then [*nxttail[0], *nxttail[1]) may contain callbacks
-	 * that batch# = rdp->batch, see the comment of struct rcu_data.
-	 */
-	batch = ACCESS_ONCE(rcp->cur) + 1;
-
-	if (rdp->nxtlist && rcu_batch_after(batch, rdp->batch)) {
-		/* process callbacks */
-		rdp->nxttail[0] = rdp->nxttail[1];
-		rdp->nxttail[1] = rdp->nxttail[2];
-		if (rcu_batch_after(batch - 1, rdp->batch))
-			rdp->nxttail[0] = rdp->nxttail[2];
-	}
-
-	rdp->batch = batch;
-	*rdp->nxttail[2] = head;
-	rdp->nxttail[2] = &head->next;
-
-	if (unlikely(++rdp->qlen > qhimark)) {
-		rdp->blimit = INT_MAX;
-		force_quiescent_state(rdp, &rcu_ctrlblk);
-	}
-}
-
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
-
-static void record_gp_stall_check_time(struct rcu_ctrlblk *rcp)
-{
-	rcp->gp_start = jiffies;
-	rcp->jiffies_stall = jiffies + RCU_SECONDS_TILL_STALL_CHECK;
-}
-
-static void print_other_cpu_stall(struct rcu_ctrlblk *rcp)
-{
-	int cpu;
-	long delta;
-	unsigned long flags;
-
-	/* Only let one CPU complain about others per time interval. */
-
-	spin_lock_irqsave(&rcp->lock, flags);
-	delta = jiffies - rcp->jiffies_stall;
-	if (delta < 2 || rcp->cur != rcp->completed) {
-		spin_unlock_irqrestore(&rcp->lock, flags);
-		return;
-	}
-	rcp->jiffies_stall = jiffies + RCU_SECONDS_TILL_STALL_RECHECK;
-	spin_unlock_irqrestore(&rcp->lock, flags);
-
-	/* OK, time to rat on our buddy... */
-
-	printk(KERN_ERR "INFO: RCU detected CPU stalls:");
-	for_each_possible_cpu(cpu) {
-		if (cpumask_test_cpu(cpu, to_cpumask(rcp->cpumask)))
-			printk(" %d", cpu);
-	}
-	printk(" (detected by %d, t=%ld jiffies)\n",
-	       smp_processor_id(), (long)(jiffies - rcp->gp_start));
-}
-
-static void print_cpu_stall(struct rcu_ctrlblk *rcp)
-{
-	unsigned long flags;
-
-	printk(KERN_ERR "INFO: RCU detected CPU %d stall (t=%lu/%lu jiffies)\n",
-			smp_processor_id(), jiffies,
-			jiffies - rcp->gp_start);
-	dump_stack();
-	spin_lock_irqsave(&rcp->lock, flags);
-	if ((long)(jiffies - rcp->jiffies_stall) >= 0)
-		rcp->jiffies_stall =
-			jiffies + RCU_SECONDS_TILL_STALL_RECHECK;
-	spin_unlock_irqrestore(&rcp->lock, flags);
-	set_need_resched();  /* kick ourselves to get things going. */
-}
-
-static void check_cpu_stall(struct rcu_ctrlblk *rcp)
-{
-	long delta;
-
-	delta = jiffies - rcp->jiffies_stall;
-	if (cpumask_test_cpu(smp_processor_id(), to_cpumask(rcp->cpumask)) &&
-		delta >= 0) {
-
-		/* We haven't checked in, so go dump stack. */
-		print_cpu_stall(rcp);
-
-	} else if (rcp->cur != rcp->completed && delta >= 2) {
-
-		/* They had two seconds to dump stack, so complain. */
-		print_other_cpu_stall(rcp);
-	}
-}
-
-#else /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
-
-static void record_gp_stall_check_time(struct rcu_ctrlblk *rcp)
-{
-}
-
-static inline void check_cpu_stall(struct rcu_ctrlblk *rcp)
-{
-}
-
-#endif /* #else #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
-
-/**
- * call_rcu - Queue an RCU callback for invocation after a grace period.
- * @head: structure to be used for queueing the RCU updates.
- * @func: actual update function to be invoked after the grace period
- *
- * The update function will be invoked some time after a full grace
- * period elapses, in other words after all currently executing RCU
- * read-side critical sections have completed.  RCU read-side critical
- * sections are delimited by rcu_read_lock() and rcu_read_unlock(),
- * and may be nested.
- */
-void call_rcu(struct rcu_head *head,
-				void (*func)(struct rcu_head *rcu))
-{
-	unsigned long flags;
-
-	head->func = func;
-	local_irq_save(flags);
-	__call_rcu(head, &rcu_ctrlblk, &__get_cpu_var(rcu_data));
-	local_irq_restore(flags);
-}
-EXPORT_SYMBOL_GPL(call_rcu);
-
-/**
- * call_rcu_bh - Queue an RCU for invocation after a quicker grace period.
- * @head: structure to be used for queueing the RCU updates.
- * @func: actual update function to be invoked after the grace period
- *
- * The update function will be invoked some time after a full grace
- * period elapses, in other words after all currently executing RCU
- * read-side critical sections have completed. call_rcu_bh() assumes
- * that the read-side critical sections end on completion of a softirq
- * handler. This means that read-side critical sections in process
- * context must not be interrupted by softirqs. This interface is to be
- * used when most of the read-side critical sections are in softirq context.
- * RCU read-side critical sections are delimited by rcu_read_lock() and
- * rcu_read_unlock(), * if in interrupt context or rcu_read_lock_bh()
- * and rcu_read_unlock_bh(), if in process context. These may be nested.
- */
-void call_rcu_bh(struct rcu_head *head,
-				void (*func)(struct rcu_head *rcu))
-{
-	unsigned long flags;
-
-	head->func = func;
-	local_irq_save(flags);
-	__call_rcu(head, &rcu_bh_ctrlblk, &__get_cpu_var(rcu_bh_data));
-	local_irq_restore(flags);
-}
-EXPORT_SYMBOL_GPL(call_rcu_bh);
-
-/*
- * Return the number of RCU batches processed thus far.  Useful
- * for debug and statistics.
- */
-long rcu_batches_completed(void)
-{
-	return rcu_ctrlblk.completed;
-}
-EXPORT_SYMBOL_GPL(rcu_batches_completed);
-
-/*
- * Return the number of RCU batches processed thus far.  Useful
- * for debug and statistics.
- */
-long rcu_batches_completed_bh(void)
-{
-	return rcu_bh_ctrlblk.completed;
-}
-EXPORT_SYMBOL_GPL(rcu_batches_completed_bh);
-
-/* Raises the softirq for processing rcu_callbacks. */
-static inline void raise_rcu_softirq(void)
-{
-	raise_softirq(RCU_SOFTIRQ);
-}
-
-/*
- * Invoke the completed RCU callbacks. They are expected to be in
- * a per-cpu list.
- */
-static void rcu_do_batch(struct rcu_data *rdp)
-{
-	unsigned long flags;
-	struct rcu_head *next, *list;
-	int count = 0;
-
-	list = rdp->donelist;
-	while (list) {
-		next = list->next;
-		prefetch(next);
-		list->func(list);
-		list = next;
-		if (++count >= rdp->blimit)
-			break;
-	}
-	rdp->donelist = list;
-
-	local_irq_save(flags);
-	rdp->qlen -= count;
-	local_irq_restore(flags);
-	if (rdp->blimit == INT_MAX && rdp->qlen <= qlowmark)
-		rdp->blimit = blimit;
-
-	if (!rdp->donelist)
-		rdp->donetail = &rdp->donelist;
-	else
-		raise_rcu_softirq();
-}
-
-/*
- * Grace period handling:
- * The grace period handling consists out of two steps:
- * - A new grace period is started.
- *   This is done by rcu_start_batch. The start is not broadcasted to
- *   all cpus, they must pick this up by comparing rcp->cur with
- *   rdp->quiescbatch. All cpus are recorded  in the
- *   rcu_ctrlblk.cpumask bitmap.
- * - All cpus must go through a quiescent state.
- *   Since the start of the grace period is not broadcasted, at least two
- *   calls to rcu_check_quiescent_state are required:
- *   The first call just notices that a new grace period is running. The
- *   following calls check if there was a quiescent state since the beginning
- *   of the grace period. If so, it updates rcu_ctrlblk.cpumask. If
- *   the bitmap is empty, then the grace period is completed.
- *   rcu_check_quiescent_state calls rcu_start_batch(0) to start the next grace
- *   period (if necessary).
- */
-
-/*
- * Register a new batch of callbacks, and start it up if there is currently no
- * active batch and the batch to be registered has not already occurred.
- * Caller must hold rcu_ctrlblk.lock.
- */
-static void rcu_start_batch(struct rcu_ctrlblk *rcp)
-{
-	if (rcp->cur != rcp->pending &&
-			rcp->completed == rcp->cur) {
-		rcp->cur++;
-		record_gp_stall_check_time(rcp);
-
-		/*
-		 * Accessing nohz_cpu_mask before incrementing rcp->cur needs a
-		 * Barrier  Otherwise it can cause tickless idle CPUs to be
-		 * included in rcp->cpumask, which will extend graceperiods
-		 * unnecessarily.
-		 */
-		smp_mb();
-		cpumask_andnot(to_cpumask(rcp->cpumask),
-			       cpu_online_mask, nohz_cpu_mask);
-
-		rcp->signaled = 0;
-	}
-}
-
-/*
- * cpu went through a quiescent state since the beginning of the grace period.
- * Clear it from the cpu mask and complete the grace period if it was the last
- * cpu. Start another grace period if someone has further entries pending
- */
-static void cpu_quiet(int cpu, struct rcu_ctrlblk *rcp)
-{
-	cpumask_clear_cpu(cpu, to_cpumask(rcp->cpumask));
-	if (cpumask_empty(to_cpumask(rcp->cpumask))) {
-		/* batch completed ! */
-		rcp->completed = rcp->cur;
-		rcu_start_batch(rcp);
-	}
-}
-
-/*
- * Check if the cpu has gone through a quiescent state (say context
- * switch). If so and if it already hasn't done so in this RCU
- * quiescent cycle, then indicate that it has done so.
- */
-static void rcu_check_quiescent_state(struct rcu_ctrlblk *rcp,
-					struct rcu_data *rdp)
-{
-	unsigned long flags;
-
-	if (rdp->quiescbatch != rcp->cur) {
-		/* start new grace period: */
-		rdp->qs_pending = 1;
-		rdp->passed_quiesc = 0;
-		rdp->quiescbatch = rcp->cur;
-		return;
-	}
-
-	/* Grace period already completed for this cpu?
-	 * qs_pending is checked instead of the actual bitmap to avoid
-	 * cacheline trashing.
-	 */
-	if (!rdp->qs_pending)
-		return;
-
-	/*
-	 * Was there a quiescent state since the beginning of the grace
-	 * period? If no, then exit and wait for the next call.
-	 */
-	if (!rdp->passed_quiesc)
-		return;
-	rdp->qs_pending = 0;
-
-	spin_lock_irqsave(&rcp->lock, flags);
-	/*
-	 * rdp->quiescbatch/rcp->cur and the cpu bitmap can come out of sync
-	 * during cpu startup. Ignore the quiescent state.
-	 */
-	if (likely(rdp->quiescbatch == rcp->cur))
-		cpu_quiet(rdp->cpu, rcp);
-
-	spin_unlock_irqrestore(&rcp->lock, flags);
-}
-
-
-#ifdef CONFIG_HOTPLUG_CPU
-
-/* warning! helper for rcu_offline_cpu. do not use elsewhere without reviewing
- * locking requirements, the list it's pulling from has to belong to a cpu
- * which is dead and hence not processing interrupts.
- */
-static void rcu_move_batch(struct rcu_data *this_rdp, struct rcu_head *list,
-				struct rcu_head **tail, long batch)
-{
-	unsigned long flags;
-
-	if (list) {
-		local_irq_save(flags);
-		this_rdp->batch = batch;
-		*this_rdp->nxttail[2] = list;
-		this_rdp->nxttail[2] = tail;
-		local_irq_restore(flags);
-	}
-}
-
-static void __rcu_offline_cpu(struct rcu_data *this_rdp,
-				struct rcu_ctrlblk *rcp, struct rcu_data *rdp)
-{
-	unsigned long flags;
-
-	/*
-	 * if the cpu going offline owns the grace period
-	 * we can block indefinitely waiting for it, so flush
-	 * it here
-	 */
-	spin_lock_irqsave(&rcp->lock, flags);
-	if (rcp->cur != rcp->completed)
-		cpu_quiet(rdp->cpu, rcp);
-	rcu_move_batch(this_rdp, rdp->donelist, rdp->donetail, rcp->cur + 1);
-	rcu_move_batch(this_rdp, rdp->nxtlist, rdp->nxttail[2], rcp->cur + 1);
-	spin_unlock(&rcp->lock);
-
-	this_rdp->qlen += rdp->qlen;
-	local_irq_restore(flags);
-}
-
-static void rcu_offline_cpu(int cpu)
-{
-	struct rcu_data *this_rdp = &get_cpu_var(rcu_data);
-	struct rcu_data *this_bh_rdp = &get_cpu_var(rcu_bh_data);
-
-	__rcu_offline_cpu(this_rdp, &rcu_ctrlblk,
-					&per_cpu(rcu_data, cpu));
-	__rcu_offline_cpu(this_bh_rdp, &rcu_bh_ctrlblk,
-					&per_cpu(rcu_bh_data, cpu));
-	put_cpu_var(rcu_data);
-	put_cpu_var(rcu_bh_data);
-}
-
-#else
-
-static void rcu_offline_cpu(int cpu)
-{
-}
-
-#endif
-
-/*
- * This does the RCU processing work from softirq context.
- */
-static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp,
-					struct rcu_data *rdp)
-{
-	unsigned long flags;
-	long completed_snap;
-
-	if (rdp->nxtlist) {
-		local_irq_save(flags);
-		completed_snap = ACCESS_ONCE(rcp->completed);
-
-		/*
-		 * move the other grace-period-completed entries to
-		 * [rdp->nxtlist, *rdp->nxttail[0]) temporarily
-		 */
-		if (!rcu_batch_before(completed_snap, rdp->batch))
-			rdp->nxttail[0] = rdp->nxttail[1] = rdp->nxttail[2];
-		else if (!rcu_batch_before(completed_snap, rdp->batch - 1))
-			rdp->nxttail[0] = rdp->nxttail[1];
-
-		/*
-		 * the grace period for entries in
-		 * [rdp->nxtlist, *rdp->nxttail[0]) has completed and
-		 * move these entries to donelist
-		 */
-		if (rdp->nxttail[0] != &rdp->nxtlist) {
-			*rdp->donetail = rdp->nxtlist;
-			rdp->donetail = rdp->nxttail[0];
-			rdp->nxtlist = *rdp->nxttail[0];
-			*rdp->donetail = NULL;
-
-			if (rdp->nxttail[1] == rdp->nxttail[0])
-				rdp->nxttail[1] = &rdp->nxtlist;
-			if (rdp->nxttail[2] == rdp->nxttail[0])
-				rdp->nxttail[2] = &rdp->nxtlist;
-			rdp->nxttail[0] = &rdp->nxtlist;
-		}
-
-		local_irq_restore(flags);
-
-		if (rcu_batch_after(rdp->batch, rcp->pending)) {
-			unsigned long flags2;
-
-			/* and start it/schedule start if it's a new batch */
-			spin_lock_irqsave(&rcp->lock, flags2);
-			if (rcu_batch_after(rdp->batch, rcp->pending)) {
-				rcp->pending = rdp->batch;
-				rcu_start_batch(rcp);
-			}
-			spin_unlock_irqrestore(&rcp->lock, flags2);
-		}
-	}
-
-	rcu_check_quiescent_state(rcp, rdp);
-	if (rdp->donelist)
-		rcu_do_batch(rdp);
-}
-
-static void rcu_process_callbacks(struct softirq_action *unused)
-{
-	/*
-	 * Memory references from any prior RCU read-side critical sections
-	 * executed by the interrupted code must be see before any RCU
-	 * grace-period manupulations below.
-	 */
-
-	smp_mb(); /* See above block comment. */
-
-	__rcu_process_callbacks(&rcu_ctrlblk, &__get_cpu_var(rcu_data));
-	__rcu_process_callbacks(&rcu_bh_ctrlblk, &__get_cpu_var(rcu_bh_data));
-
-	/*
-	 * Memory references from any later RCU read-side critical sections
-	 * executed by the interrupted code must be see after any RCU
-	 * grace-period manupulations above.
-	 */
-
-	smp_mb(); /* See above block comment. */
-}
-
-static int __rcu_pending(struct rcu_ctrlblk *rcp, struct rcu_data *rdp)
-{
-	/* Check for CPU stalls, if enabled. */
-	check_cpu_stall(rcp);
-
-	if (rdp->nxtlist) {
-		long completed_snap = ACCESS_ONCE(rcp->completed);
-
-		/*
-		 * This cpu has pending rcu entries and the grace period
-		 * for them has completed.
-		 */
-		if (!rcu_batch_before(completed_snap, rdp->batch))
-			return 1;
-		if (!rcu_batch_before(completed_snap, rdp->batch - 1) &&
-				rdp->nxttail[0] != rdp->nxttail[1])
-			return 1;
-		if (rdp->nxttail[0] != &rdp->nxtlist)
-			return 1;
-
-		/*
-		 * This cpu has pending rcu entries and the new batch
-		 * for then hasn't been started nor scheduled start
-		 */
-		if (rcu_batch_after(rdp->batch, rcp->pending))
-			return 1;
-	}
-
-	/* This cpu has finished callbacks to invoke */
-	if (rdp->donelist)
-		return 1;
-
-	/* The rcu core waits for a quiescent state from the cpu */
-	if (rdp->quiescbatch != rcp->cur || rdp->qs_pending)
-		return 1;
-
-	/* nothing to do */
-	return 0;
-}
-
-/*
- * Check to see if there is any immediate RCU-related work to be done
- * by the current CPU, returning 1 if so.  This function is part of the
- * RCU implementation; it is -not- an exported member of the RCU API.
- */
-int rcu_pending(int cpu)
-{
-	return __rcu_pending(&rcu_ctrlblk, &per_cpu(rcu_data, cpu)) ||
-		__rcu_pending(&rcu_bh_ctrlblk, &per_cpu(rcu_bh_data, cpu));
-}
-
-/*
- * Check to see if any future RCU-related work will need to be done
- * by the current CPU, even if none need be done immediately, returning
- * 1 if so.  This function is part of the RCU implementation; it is -not-
- * an exported member of the RCU API.
- */
-int rcu_needs_cpu(int cpu)
-{
-	struct rcu_data *rdp = &per_cpu(rcu_data, cpu);
-	struct rcu_data *rdp_bh = &per_cpu(rcu_bh_data, cpu);
-
-	return !!rdp->nxtlist || !!rdp_bh->nxtlist || rcu_pending(cpu);
-}
-
-/*
- * Top-level function driving RCU grace-period detection, normally
- * invoked from the scheduler-clock interrupt.  This function simply
- * increments counters that are read only from softirq by this same
- * CPU, so there are no memory barriers required.
- */
-void rcu_check_callbacks(int cpu, int user)
-{
-	if (user ||
-	    (idle_cpu(cpu) && rcu_scheduler_active &&
-	     !in_softirq() && hardirq_count() <= (1 << HARDIRQ_SHIFT))) {
-
-		/*
-		 * Get here if this CPU took its interrupt from user
-		 * mode or from the idle loop, and if this is not a
-		 * nested interrupt.  In this case, the CPU is in
-		 * a quiescent state, so count it.
-		 *
-		 * Also do a memory barrier.  This is needed to handle
-		 * the case where writes from a preempt-disable section
-		 * of code get reordered into schedule() by this CPU's
-		 * write buffer.  The memory barrier makes sure that
-		 * the rcu_qsctr_inc() and rcu_bh_qsctr_inc() are see
-		 * by other CPUs to happen after any such write.
-		 */
-
-		smp_mb();  /* See above block comment. */
-		rcu_qsctr_inc(cpu);
-		rcu_bh_qsctr_inc(cpu);
-
-	} else if (!in_softirq()) {
-
-		/*
-		 * Get here if this CPU did not take its interrupt from
-		 * softirq, in other words, if it is not interrupting
-		 * a rcu_bh read-side critical section.  This is an _bh
-		 * critical section, so count it.  The memory barrier
-		 * is needed for the same reason as is the above one.
-		 */
-
-		smp_mb();  /* See above block comment. */
-		rcu_bh_qsctr_inc(cpu);
-	}
-	raise_rcu_softirq();
-}
-
-static void __cpuinit rcu_init_percpu_data(int cpu, struct rcu_ctrlblk *rcp,
-						struct rcu_data *rdp)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&rcp->lock, flags);
-	memset(rdp, 0, sizeof(*rdp));
-	rdp->nxttail[0] = rdp->nxttail[1] = rdp->nxttail[2] = &rdp->nxtlist;
-	rdp->donetail = &rdp->donelist;
-	rdp->quiescbatch = rcp->completed;
-	rdp->qs_pending = 0;
-	rdp->cpu = cpu;
-	rdp->blimit = blimit;
-	spin_unlock_irqrestore(&rcp->lock, flags);
-}
-
-static void __cpuinit rcu_online_cpu(int cpu)
-{
-	struct rcu_data *rdp = &per_cpu(rcu_data, cpu);
-	struct rcu_data *bh_rdp = &per_cpu(rcu_bh_data, cpu);
-
-	rcu_init_percpu_data(cpu, &rcu_ctrlblk, rdp);
-	rcu_init_percpu_data(cpu, &rcu_bh_ctrlblk, bh_rdp);
-	open_softirq(RCU_SOFTIRQ, rcu_process_callbacks);
-}
-
-static int __cpuinit rcu_cpu_notify(struct notifier_block *self,
-				unsigned long action, void *hcpu)
-{
-	long cpu = (long)hcpu;
-
-	switch (action) {
-	case CPU_UP_PREPARE:
-	case CPU_UP_PREPARE_FROZEN:
-		rcu_online_cpu(cpu);
-		break;
-	case CPU_DEAD:
-	case CPU_DEAD_FROZEN:
-		rcu_offline_cpu(cpu);
-		break;
-	default:
-		break;
-	}
-	return NOTIFY_OK;
-}
-
-static struct notifier_block __cpuinitdata rcu_nb = {
-	.notifier_call	= rcu_cpu_notify,
-};
-
-/*
- * Initializes rcu mechanism.  Assumed to be called early.
- * That is before local timer(SMP) or jiffie timer (uniproc) is setup.
- * Note that rcu_qsctr and friends are implicitly
- * initialized due to the choice of ``0'' for RCU_CTR_INVALID.
- */
-void __init __rcu_init(void)
-{
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
-	printk(KERN_INFO "RCU-based detection of stalled CPUs is enabled.\n");
-#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
-	rcu_cpu_notify(&rcu_nb, CPU_UP_PREPARE,
-			(void *)(long)smp_processor_id());
-	/* Register notifier for non-boot CPUs */
-	register_cpu_notifier(&rcu_nb);
-}
-
-module_param(blimit, int, 0);
-module_param(qhimark, int, 0);
-module_param(qlowmark, int, 0);
diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c
index a967c9f..37ac454 100644
--- a/kernel/rcupdate.c
+++ b/kernel/rcupdate.c
@@ -19,7 +19,7 @@
  *
  * Authors: Dipankar Sarma <dipankar@in.ibm.com>
  *	    Manfred Spraul <manfred@colorfullife.com>
- * 
+ *
  * Based on the original work by Paul McKenney <paulmck@us.ibm.com>
  * and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen.
  * Papers:
@@ -27,7 +27,7 @@
  * http://lse.sourceforge.net/locking/rclock_OLS.2001.05.01c.sc.pdf (OLS2001)
  *
  * For detailed explanation of Read-Copy Update mechanism see -
- * 		http://lse.sourceforge.net/locking/rcupdate.html
+ *		http://lse.sourceforge.net/locking/rcupdate.html
  *
  */
 #include <linux/types.h>
@@ -74,6 +74,8 @@ void wakeme_after_rcu(struct rcu_head  *head)
 	complete(&rcu->completion);
 }
 
+#ifdef CONFIG_TREE_PREEMPT_RCU
+
 /**
  * synchronize_rcu - wait until a grace period has elapsed.
  *
@@ -87,7 +89,7 @@ void synchronize_rcu(void)
 {
 	struct rcu_synchronize rcu;
 
-	if (rcu_blocking_is_gp())
+	if (!rcu_scheduler_active)
 		return;
 
 	init_completion(&rcu.completion);
@@ -98,6 +100,70 @@ void synchronize_rcu(void)
 }
 EXPORT_SYMBOL_GPL(synchronize_rcu);
 
+#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+
+/**
+ * synchronize_sched - wait until an rcu-sched grace period has elapsed.
+ *
+ * Control will return to the caller some time after a full rcu-sched
+ * grace period has elapsed, in other words after all currently executing
+ * rcu-sched read-side critical sections have completed.   These read-side
+ * critical sections are delimited by rcu_read_lock_sched() and
+ * rcu_read_unlock_sched(), and may be nested.  Note that preempt_disable(),
+ * local_irq_disable(), and so on may be used in place of
+ * rcu_read_lock_sched().
+ *
+ * This means that all preempt_disable code sequences, including NMI and
+ * hardware-interrupt handlers, in progress on entry will have completed
+ * before this primitive returns.  However, this does not guarantee that
+ * softirq handlers will have completed, since in some kernels, these
+ * handlers can run in process context, and can block.
+ *
+ * This primitive provides the guarantees made by the (now removed)
+ * synchronize_kernel() API.  In contrast, synchronize_rcu() only
+ * guarantees that rcu_read_lock() sections will have completed.
+ * In "classic RCU", these two guarantees happen to be one and
+ * the same, but can differ in realtime RCU implementations.
+ */
+void synchronize_sched(void)
+{
+	struct rcu_synchronize rcu;
+
+	if (rcu_blocking_is_gp())
+		return;
+
+	init_completion(&rcu.completion);
+	/* Will wake me after RCU finished. */
+	call_rcu_sched(&rcu.head, wakeme_after_rcu);
+	/* Wait for it. */
+	wait_for_completion(&rcu.completion);
+}
+EXPORT_SYMBOL_GPL(synchronize_sched);
+
+/**
+ * synchronize_rcu_bh - wait until an rcu_bh grace period has elapsed.
+ *
+ * Control will return to the caller some time after a full rcu_bh grace
+ * period has elapsed, in other words after all currently executing rcu_bh
+ * read-side critical sections have completed.  RCU read-side critical
+ * sections are delimited by rcu_read_lock_bh() and rcu_read_unlock_bh(),
+ * and may be nested.
+ */
+void synchronize_rcu_bh(void)
+{
+	struct rcu_synchronize rcu;
+
+	if (rcu_blocking_is_gp())
+		return;
+
+	init_completion(&rcu.completion);
+	/* Will wake me after RCU finished. */
+	call_rcu_bh(&rcu.head, wakeme_after_rcu);
+	/* Wait for it. */
+	wait_for_completion(&rcu.completion);
+}
+EXPORT_SYMBOL_GPL(synchronize_rcu_bh);
+
 static void rcu_barrier_callback(struct rcu_head *notused)
 {
 	if (atomic_dec_and_test(&rcu_barrier_cpu_count))
@@ -129,6 +195,7 @@ static void rcu_barrier_func(void *type)
 static inline void wait_migrated_callbacks(void)
 {
 	wait_event(rcu_migrate_wq, !atomic_read(&rcu_migrate_type_count));
+	smp_mb(); /* In case we didn't sleep. */
 }
 
 /*
@@ -192,9 +259,13 @@ static void rcu_migrate_callback(struct rcu_head *notused)
 		wake_up(&rcu_migrate_wq);
 }
 
+extern int rcu_cpu_notify(struct notifier_block *self,
+			  unsigned long action, void *hcpu);
+
 static int __cpuinit rcu_barrier_cpu_hotplug(struct notifier_block *self,
 		unsigned long action, void *hcpu)
 {
+	rcu_cpu_notify(self, action, hcpu);
 	if (action == CPU_DYING) {
 		/*
 		 * preempt_disable() in on_each_cpu() prevents stop_machine(),
@@ -209,7 +280,8 @@ static int __cpuinit rcu_barrier_cpu_hotplug(struct notifier_block *self,
 		call_rcu_bh(rcu_migrate_head, rcu_migrate_callback);
 		call_rcu_sched(rcu_migrate_head + 1, rcu_migrate_callback);
 		call_rcu(rcu_migrate_head + 2, rcu_migrate_callback);
-	} else if (action == CPU_POST_DEAD) {
+	} else if (action == CPU_DOWN_PREPARE) {
+		/* Don't need to wait until next removal operation. */
 		/* rcu_migrate_head is protected by cpu_add_remove_lock */
 		wait_migrated_callbacks();
 	}
@@ -219,8 +291,18 @@ static int __cpuinit rcu_barrier_cpu_hotplug(struct notifier_block *self,
 
 void __init rcu_init(void)
 {
+	int i;
+
 	__rcu_init();
-	hotcpu_notifier(rcu_barrier_cpu_hotplug, 0);
+	cpu_notifier(rcu_barrier_cpu_hotplug, 0);
+
+	/*
+	 * We don't need protection against CPU-hotplug here because
+	 * this is called early in boot, before either interrupts
+	 * or the scheduler are operational.
+	 */
+	for_each_online_cpu(i)
+		rcu_barrier_cpu_hotplug(NULL, CPU_UP_PREPARE, (void *)(long)i);
 }
 
 void rcu_scheduler_starting(void)
diff --git a/kernel/rcupreempt.c b/kernel/rcupreempt.c
deleted file mode 100644
index beb0e65..0000000
--- a/kernel/rcupreempt.c
+++ /dev/null
@@ -1,1539 +0,0 @@
-/*
- * Read-Copy Update mechanism for mutual exclusion, realtime implementation
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
- * Copyright IBM Corporation, 2006
- *
- * Authors: Paul E. McKenney <paulmck@us.ibm.com>
- *		With thanks to Esben Nielsen, Bill Huey, and Ingo Molnar
- *		for pushing me away from locks and towards counters, and
- *		to Suparna Bhattacharya for pushing me completely away
- *		from atomic instructions on the read side.
- *
- *  - Added handling of Dynamic Ticks
- *      Copyright 2007 - Paul E. Mckenney <paulmck@us.ibm.com>
- *                     - Steven Rostedt <srostedt@redhat.com>
- *
- * Papers:  http://www.rdrop.com/users/paulmck/RCU
- *
- * Design Document: http://lwn.net/Articles/253651/
- *
- * For detailed explanation of Read-Copy Update mechanism see -
- * 		Documentation/RCU/ *.txt
- *
- */
-#include <linux/types.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/spinlock.h>
-#include <linux/smp.h>
-#include <linux/rcupdate.h>
-#include <linux/interrupt.h>
-#include <linux/sched.h>
-#include <asm/atomic.h>
-#include <linux/bitops.h>
-#include <linux/module.h>
-#include <linux/kthread.h>
-#include <linux/completion.h>
-#include <linux/moduleparam.h>
-#include <linux/percpu.h>
-#include <linux/notifier.h>
-#include <linux/cpu.h>
-#include <linux/random.h>
-#include <linux/delay.h>
-#include <linux/cpumask.h>
-#include <linux/rcupreempt_trace.h>
-#include <asm/byteorder.h>
-
-/*
- * PREEMPT_RCU data structures.
- */
-
-/*
- * GP_STAGES specifies the number of times the state machine has
- * to go through the all the rcu_try_flip_states (see below)
- * in a single Grace Period.
- *
- * GP in GP_STAGES stands for Grace Period ;)
- */
-#define GP_STAGES    2
-struct rcu_data {
-	spinlock_t	lock;		/* Protect rcu_data fields. */
-	long		completed;	/* Number of last completed batch. */
-	int		waitlistcount;
-	struct rcu_head *nextlist;
-	struct rcu_head **nexttail;
-	struct rcu_head *waitlist[GP_STAGES];
-	struct rcu_head **waittail[GP_STAGES];
-	struct rcu_head *donelist;	/* from waitlist & waitschedlist */
-	struct rcu_head **donetail;
-	long rcu_flipctr[2];
-	struct rcu_head *nextschedlist;
-	struct rcu_head **nextschedtail;
-	struct rcu_head *waitschedlist;
-	struct rcu_head **waitschedtail;
-	int rcu_sched_sleeping;
-#ifdef CONFIG_RCU_TRACE
-	struct rcupreempt_trace trace;
-#endif /* #ifdef CONFIG_RCU_TRACE */
-};
-
-/*
- * States for rcu_try_flip() and friends.
- */
-
-enum rcu_try_flip_states {
-
-	/*
-	 * Stay here if nothing is happening. Flip the counter if somthing
-	 * starts happening. Denoted by "I"
-	 */
-	rcu_try_flip_idle_state,
-
-	/*
-	 * Wait here for all CPUs to notice that the counter has flipped. This
-	 * prevents the old set of counters from ever being incremented once
-	 * we leave this state, which in turn is necessary because we cannot
-	 * test any individual counter for zero -- we can only check the sum.
-	 * Denoted by "A".
-	 */
-	rcu_try_flip_waitack_state,
-
-	/*
-	 * Wait here for the sum of the old per-CPU counters to reach zero.
-	 * Denoted by "Z".
-	 */
-	rcu_try_flip_waitzero_state,
-
-	/*
-	 * Wait here for each of the other CPUs to execute a memory barrier.
-	 * This is necessary to ensure that these other CPUs really have
-	 * completed executing their RCU read-side critical sections, despite
-	 * their CPUs wildly reordering memory. Denoted by "M".
-	 */
-	rcu_try_flip_waitmb_state,
-};
-
-/*
- * States for rcu_ctrlblk.rcu_sched_sleep.
- */
-
-enum rcu_sched_sleep_states {
-	rcu_sched_not_sleeping,	/* Not sleeping, callbacks need GP.  */
-	rcu_sched_sleep_prep,	/* Thinking of sleeping, rechecking. */
-	rcu_sched_sleeping,	/* Sleeping, awaken if GP needed. */
-};
-
-struct rcu_ctrlblk {
-	spinlock_t	fliplock;	/* Protect state-machine transitions. */
-	long		completed;	/* Number of last completed batch. */
-	enum rcu_try_flip_states rcu_try_flip_state; /* The current state of
-							the rcu state machine */
-	spinlock_t	schedlock;	/* Protect rcu_sched sleep state. */
-	enum rcu_sched_sleep_states sched_sleep; /* rcu_sched state. */
-	wait_queue_head_t sched_wq;	/* Place for rcu_sched to sleep. */
-};
-
-struct rcu_dyntick_sched {
-	int dynticks;
-	int dynticks_snap;
-	int sched_qs;
-	int sched_qs_snap;
-	int sched_dynticks_snap;
-};
-
-static DEFINE_PER_CPU_SHARED_ALIGNED(struct rcu_dyntick_sched, rcu_dyntick_sched) = {
-	.dynticks = 1,
-};
-
-void rcu_qsctr_inc(int cpu)
-{
-	struct rcu_dyntick_sched *rdssp = &per_cpu(rcu_dyntick_sched, cpu);
-
-	rdssp->sched_qs++;
-}
-
-#ifdef CONFIG_NO_HZ
-
-void rcu_enter_nohz(void)
-{
-	static DEFINE_RATELIMIT_STATE(rs, 10 * HZ, 1);
-
-	smp_mb(); /* CPUs seeing ++ must see prior RCU read-side crit sects */
-	__get_cpu_var(rcu_dyntick_sched).dynticks++;
-	WARN_ON_RATELIMIT(__get_cpu_var(rcu_dyntick_sched).dynticks & 0x1, &rs);
-}
-
-void rcu_exit_nohz(void)
-{
-	static DEFINE_RATELIMIT_STATE(rs, 10 * HZ, 1);
-
-	__get_cpu_var(rcu_dyntick_sched).dynticks++;
-	smp_mb(); /* CPUs seeing ++ must see later RCU read-side crit sects */
-	WARN_ON_RATELIMIT(!(__get_cpu_var(rcu_dyntick_sched).dynticks & 0x1),
-				&rs);
-}
-
-#endif /* CONFIG_NO_HZ */
-
-
-static DEFINE_PER_CPU(struct rcu_data, rcu_data);
-
-static struct rcu_ctrlblk rcu_ctrlblk = {
-	.fliplock = __SPIN_LOCK_UNLOCKED(rcu_ctrlblk.fliplock),
-	.completed = 0,
-	.rcu_try_flip_state = rcu_try_flip_idle_state,
-	.schedlock = __SPIN_LOCK_UNLOCKED(rcu_ctrlblk.schedlock),
-	.sched_sleep = rcu_sched_not_sleeping,
-	.sched_wq = __WAIT_QUEUE_HEAD_INITIALIZER(rcu_ctrlblk.sched_wq),
-};
-
-static struct task_struct *rcu_sched_grace_period_task;
-
-#ifdef CONFIG_RCU_TRACE
-static char *rcu_try_flip_state_names[] =
-	{ "idle", "waitack", "waitzero", "waitmb" };
-#endif /* #ifdef CONFIG_RCU_TRACE */
-
-static DECLARE_BITMAP(rcu_cpu_online_map, NR_CPUS) __read_mostly
-	= CPU_BITS_NONE;
-
-/*
- * Enum and per-CPU flag to determine when each CPU has seen
- * the most recent counter flip.
- */
-
-enum rcu_flip_flag_values {
-	rcu_flip_seen,		/* Steady/initial state, last flip seen. */
-				/* Only GP detector can update. */
-	rcu_flipped		/* Flip just completed, need confirmation. */
-				/* Only corresponding CPU can update. */
-};
-static DEFINE_PER_CPU_SHARED_ALIGNED(enum rcu_flip_flag_values, rcu_flip_flag)
-								= rcu_flip_seen;
-
-/*
- * Enum and per-CPU flag to determine when each CPU has executed the
- * needed memory barrier to fence in memory references from its last RCU
- * read-side critical section in the just-completed grace period.
- */
-
-enum rcu_mb_flag_values {
-	rcu_mb_done,		/* Steady/initial state, no mb()s required. */
-				/* Only GP detector can update. */
-	rcu_mb_needed		/* Flip just completed, need an mb(). */
-				/* Only corresponding CPU can update. */
-};
-static DEFINE_PER_CPU_SHARED_ALIGNED(enum rcu_mb_flag_values, rcu_mb_flag)
-								= rcu_mb_done;
-
-/*
- * RCU_DATA_ME: find the current CPU's rcu_data structure.
- * RCU_DATA_CPU: find the specified CPU's rcu_data structure.
- */
-#define RCU_DATA_ME()		(&__get_cpu_var(rcu_data))
-#define RCU_DATA_CPU(cpu)	(&per_cpu(rcu_data, cpu))
-
-/*
- * Helper macro for tracing when the appropriate rcu_data is not
- * cached in a local variable, but where the CPU number is so cached.
- */
-#define RCU_TRACE_CPU(f, cpu) RCU_TRACE(f, &(RCU_DATA_CPU(cpu)->trace));
-
-/*
- * Helper macro for tracing when the appropriate rcu_data is not
- * cached in a local variable.
- */
-#define RCU_TRACE_ME(f) RCU_TRACE(f, &(RCU_DATA_ME()->trace));
-
-/*
- * Helper macro for tracing when the appropriate rcu_data is pointed
- * to by a local variable.
- */
-#define RCU_TRACE_RDP(f, rdp) RCU_TRACE(f, &((rdp)->trace));
-
-#define RCU_SCHED_BATCH_TIME (HZ / 50)
-
-/*
- * Return the number of RCU batches processed thus far.  Useful
- * for debug and statistics.
- */
-long rcu_batches_completed(void)
-{
-	return rcu_ctrlblk.completed;
-}
-EXPORT_SYMBOL_GPL(rcu_batches_completed);
-
-void __rcu_read_lock(void)
-{
-	int idx;
-	struct task_struct *t = current;
-	int nesting;
-
-	nesting = ACCESS_ONCE(t->rcu_read_lock_nesting);
-	if (nesting != 0) {
-
-		/* An earlier rcu_read_lock() covers us, just count it. */
-
-		t->rcu_read_lock_nesting = nesting + 1;
-
-	} else {
-		unsigned long flags;
-
-		/*
-		 * We disable interrupts for the following reasons:
-		 * - If we get scheduling clock interrupt here, and we
-		 *   end up acking the counter flip, it's like a promise
-		 *   that we will never increment the old counter again.
-		 *   Thus we will break that promise if that
-		 *   scheduling clock interrupt happens between the time
-		 *   we pick the .completed field and the time that we
-		 *   increment our counter.
-		 *
-		 * - We don't want to be preempted out here.
-		 *
-		 * NMIs can still occur, of course, and might themselves
-		 * contain rcu_read_lock().
-		 */
-
-		local_irq_save(flags);
-
-		/*
-		 * Outermost nesting of rcu_read_lock(), so increment
-		 * the current counter for the current CPU.  Use volatile
-		 * casts to prevent the compiler from reordering.
-		 */
-
-		idx = ACCESS_ONCE(rcu_ctrlblk.completed) & 0x1;
-		ACCESS_ONCE(RCU_DATA_ME()->rcu_flipctr[idx])++;
-
-		/*
-		 * Now that the per-CPU counter has been incremented, we
-		 * are protected from races with rcu_read_lock() invoked
-		 * from NMI handlers on this CPU.  We can therefore safely
-		 * increment the nesting counter, relieving further NMIs
-		 * of the need to increment the per-CPU counter.
-		 */
-
-		ACCESS_ONCE(t->rcu_read_lock_nesting) = nesting + 1;
-
-		/*
-		 * Now that we have preventing any NMIs from storing
-		 * to the ->rcu_flipctr_idx, we can safely use it to
-		 * remember which counter to decrement in the matching
-		 * rcu_read_unlock().
-		 */
-
-		ACCESS_ONCE(t->rcu_flipctr_idx) = idx;
-		local_irq_restore(flags);
-	}
-}
-EXPORT_SYMBOL_GPL(__rcu_read_lock);
-
-void __rcu_read_unlock(void)
-{
-	int idx;
-	struct task_struct *t = current;
-	int nesting;
-
-	nesting = ACCESS_ONCE(t->rcu_read_lock_nesting);
-	if (nesting > 1) {
-
-		/*
-		 * We are still protected by the enclosing rcu_read_lock(),
-		 * so simply decrement the counter.
-		 */
-
-		t->rcu_read_lock_nesting = nesting - 1;
-
-	} else {
-		unsigned long flags;
-
-		/*
-		 * Disable local interrupts to prevent the grace-period
-		 * detection state machine from seeing us half-done.
-		 * NMIs can still occur, of course, and might themselves
-		 * contain rcu_read_lock() and rcu_read_unlock().
-		 */
-
-		local_irq_save(flags);
-
-		/*
-		 * Outermost nesting of rcu_read_unlock(), so we must
-		 * decrement the current counter for the current CPU.
-		 * This must be done carefully, because NMIs can
-		 * occur at any point in this code, and any rcu_read_lock()
-		 * and rcu_read_unlock() pairs in the NMI handlers
-		 * must interact non-destructively with this code.
-		 * Lots of volatile casts, and -very- careful ordering.
-		 *
-		 * Changes to this code, including this one, must be
-		 * inspected, validated, and tested extremely carefully!!!
-		 */
-
-		/*
-		 * First, pick up the index.
-		 */
-
-		idx = ACCESS_ONCE(t->rcu_flipctr_idx);
-
-		/*
-		 * Now that we have fetched the counter index, it is
-		 * safe to decrement the per-task RCU nesting counter.
-		 * After this, any interrupts or NMIs will increment and
-		 * decrement the per-CPU counters.
-		 */
-		ACCESS_ONCE(t->rcu_read_lock_nesting) = nesting - 1;
-
-		/*
-		 * It is now safe to decrement this task's nesting count.
-		 * NMIs that occur after this statement will route their
-		 * rcu_read_lock() calls through this "else" clause, and
-		 * will thus start incrementing the per-CPU counter on
-		 * their own.  They will also clobber ->rcu_flipctr_idx,
-		 * but that is OK, since we have already fetched it.
-		 */
-
-		ACCESS_ONCE(RCU_DATA_ME()->rcu_flipctr[idx])--;
-		local_irq_restore(flags);
-	}
-}
-EXPORT_SYMBOL_GPL(__rcu_read_unlock);
-
-/*
- * If a global counter flip has occurred since the last time that we
- * advanced callbacks, advance them.  Hardware interrupts must be
- * disabled when calling this function.
- */
-static void __rcu_advance_callbacks(struct rcu_data *rdp)
-{
-	int cpu;
-	int i;
-	int wlc = 0;
-
-	if (rdp->completed != rcu_ctrlblk.completed) {
-		if (rdp->waitlist[GP_STAGES - 1] != NULL) {
-			*rdp->donetail = rdp->waitlist[GP_STAGES - 1];
-			rdp->donetail = rdp->waittail[GP_STAGES - 1];
-			RCU_TRACE_RDP(rcupreempt_trace_move2done, rdp);
-		}
-		for (i = GP_STAGES - 2; i >= 0; i--) {
-			if (rdp->waitlist[i] != NULL) {
-				rdp->waitlist[i + 1] = rdp->waitlist[i];
-				rdp->waittail[i + 1] = rdp->waittail[i];
-				wlc++;
-			} else {
-				rdp->waitlist[i + 1] = NULL;
-				rdp->waittail[i + 1] =
-					&rdp->waitlist[i + 1];
-			}
-		}
-		if (rdp->nextlist != NULL) {
-			rdp->waitlist[0] = rdp->nextlist;
-			rdp->waittail[0] = rdp->nexttail;
-			wlc++;
-			rdp->nextlist = NULL;
-			rdp->nexttail = &rdp->nextlist;
-			RCU_TRACE_RDP(rcupreempt_trace_move2wait, rdp);
-		} else {
-			rdp->waitlist[0] = NULL;
-			rdp->waittail[0] = &rdp->waitlist[0];
-		}
-		rdp->waitlistcount = wlc;
-		rdp->completed = rcu_ctrlblk.completed;
-	}
-
-	/*
-	 * Check to see if this CPU needs to report that it has seen
-	 * the most recent counter flip, thereby declaring that all
-	 * subsequent rcu_read_lock() invocations will respect this flip.
-	 */
-
-	cpu = raw_smp_processor_id();
-	if (per_cpu(rcu_flip_flag, cpu) == rcu_flipped) {
-		smp_mb();  /* Subsequent counter accesses must see new value */
-		per_cpu(rcu_flip_flag, cpu) = rcu_flip_seen;
-		smp_mb();  /* Subsequent RCU read-side critical sections */
-			   /*  seen -after- acknowledgement. */
-	}
-}
-
-#ifdef CONFIG_NO_HZ
-static DEFINE_PER_CPU(int, rcu_update_flag);
-
-/**
- * rcu_irq_enter - Called from Hard irq handlers and NMI/SMI.
- *
- * If the CPU was idle with dynamic ticks active, this updates the
- * rcu_dyntick_sched.dynticks to let the RCU handling know that the
- * CPU is active.
- */
-void rcu_irq_enter(void)
-{
-	int cpu = smp_processor_id();
-	struct rcu_dyntick_sched *rdssp = &per_cpu(rcu_dyntick_sched, cpu);
-
-	if (per_cpu(rcu_update_flag, cpu))
-		per_cpu(rcu_update_flag, cpu)++;
-
-	/*
-	 * Only update if we are coming from a stopped ticks mode
-	 * (rcu_dyntick_sched.dynticks is even).
-	 */
-	if (!in_interrupt() &&
-	    (rdssp->dynticks & 0x1) == 0) {
-		/*
-		 * The following might seem like we could have a race
-		 * with NMI/SMIs. But this really isn't a problem.
-		 * Here we do a read/modify/write, and the race happens
-		 * when an NMI/SMI comes in after the read and before
-		 * the write. But NMI/SMIs will increment this counter
-		 * twice before returning, so the zero bit will not
-		 * be corrupted by the NMI/SMI which is the most important
-		 * part.
-		 *
-		 * The only thing is that we would bring back the counter
-		 * to a postion that it was in during the NMI/SMI.
-		 * But the zero bit would be set, so the rest of the
-		 * counter would again be ignored.
-		 *
-		 * On return from the IRQ, the counter may have the zero
-		 * bit be 0 and the counter the same as the return from
-		 * the NMI/SMI. If the state machine was so unlucky to
-		 * see that, it still doesn't matter, since all
-		 * RCU read-side critical sections on this CPU would
-		 * have already completed.
-		 */
-		rdssp->dynticks++;
-		/*
-		 * The following memory barrier ensures that any
-		 * rcu_read_lock() primitives in the irq handler
-		 * are seen by other CPUs to follow the above
-		 * increment to rcu_dyntick_sched.dynticks. This is
-		 * required in order for other CPUs to correctly
-		 * determine when it is safe to advance the RCU
-		 * grace-period state machine.
-		 */
-		smp_mb(); /* see above block comment. */
-		/*
-		 * Since we can't determine the dynamic tick mode from
-		 * the rcu_dyntick_sched.dynticks after this routine,
-		 * we use a second flag to acknowledge that we came
-		 * from an idle state with ticks stopped.
-		 */
-		per_cpu(rcu_update_flag, cpu)++;
-		/*
-		 * If we take an NMI/SMI now, they will also increment
-		 * the rcu_update_flag, and will not update the
-		 * rcu_dyntick_sched.dynticks on exit. That is for
-		 * this IRQ to do.
-		 */
-	}
-}
-
-/**
- * rcu_irq_exit - Called from exiting Hard irq context.
- *
- * If the CPU was idle with dynamic ticks active, update the
- * rcu_dyntick_sched.dynticks to put let the RCU handling be
- * aware that the CPU is going back to idle with no ticks.
- */
-void rcu_irq_exit(void)
-{
-	int cpu = smp_processor_id();
-	struct rcu_dyntick_sched *rdssp = &per_cpu(rcu_dyntick_sched, cpu);
-
-	/*
-	 * rcu_update_flag is set if we interrupted the CPU
-	 * when it was idle with ticks stopped.
-	 * Once this occurs, we keep track of interrupt nesting
-	 * because a NMI/SMI could also come in, and we still
-	 * only want the IRQ that started the increment of the
-	 * rcu_dyntick_sched.dynticks to be the one that modifies
-	 * it on exit.
-	 */
-	if (per_cpu(rcu_update_flag, cpu)) {
-		if (--per_cpu(rcu_update_flag, cpu))
-			return;
-
-		/* This must match the interrupt nesting */
-		WARN_ON(in_interrupt());
-
-		/*
-		 * If an NMI/SMI happens now we are still
-		 * protected by the rcu_dyntick_sched.dynticks being odd.
-		 */
-
-		/*
-		 * The following memory barrier ensures that any
-		 * rcu_read_unlock() primitives in the irq handler
-		 * are seen by other CPUs to preceed the following
-		 * increment to rcu_dyntick_sched.dynticks. This
-		 * is required in order for other CPUs to determine
-		 * when it is safe to advance the RCU grace-period
-		 * state machine.
-		 */
-		smp_mb(); /* see above block comment. */
-		rdssp->dynticks++;
-		WARN_ON(rdssp->dynticks & 0x1);
-	}
-}
-
-void rcu_nmi_enter(void)
-{
-	rcu_irq_enter();
-}
-
-void rcu_nmi_exit(void)
-{
-	rcu_irq_exit();
-}
-
-static void dyntick_save_progress_counter(int cpu)
-{
-	struct rcu_dyntick_sched *rdssp = &per_cpu(rcu_dyntick_sched, cpu);
-
-	rdssp->dynticks_snap = rdssp->dynticks;
-}
-
-static inline int
-rcu_try_flip_waitack_needed(int cpu)
-{
-	long curr;
-	long snap;
-	struct rcu_dyntick_sched *rdssp = &per_cpu(rcu_dyntick_sched, cpu);
-
-	curr = rdssp->dynticks;
-	snap = rdssp->dynticks_snap;
-	smp_mb(); /* force ordering with cpu entering/leaving dynticks. */
-
-	/*
-	 * If the CPU remained in dynticks mode for the entire time
-	 * and didn't take any interrupts, NMIs, SMIs, or whatever,
-	 * then it cannot be in the middle of an rcu_read_lock(), so
-	 * the next rcu_read_lock() it executes must use the new value
-	 * of the counter.  So we can safely pretend that this CPU
-	 * already acknowledged the counter.
-	 */
-
-	if ((curr == snap) && ((curr & 0x1) == 0))
-		return 0;
-
-	/*
-	 * If the CPU passed through or entered a dynticks idle phase with
-	 * no active irq handlers, then, as above, we can safely pretend
-	 * that this CPU already acknowledged the counter.
-	 */
-
-	if ((curr - snap) > 2 || (curr & 0x1) == 0)
-		return 0;
-
-	/* We need this CPU to explicitly acknowledge the counter flip. */
-
-	return 1;
-}
-
-static inline int
-rcu_try_flip_waitmb_needed(int cpu)
-{
-	long curr;
-	long snap;
-	struct rcu_dyntick_sched *rdssp = &per_cpu(rcu_dyntick_sched, cpu);
-
-	curr = rdssp->dynticks;
-	snap = rdssp->dynticks_snap;
-	smp_mb(); /* force ordering with cpu entering/leaving dynticks. */
-
-	/*
-	 * If the CPU remained in dynticks mode for the entire time
-	 * and didn't take any interrupts, NMIs, SMIs, or whatever,
-	 * then it cannot have executed an RCU read-side critical section
-	 * during that time, so there is no need for it to execute a
-	 * memory barrier.
-	 */
-
-	if ((curr == snap) && ((curr & 0x1) == 0))
-		return 0;
-
-	/*
-	 * If the CPU either entered or exited an outermost interrupt,
-	 * SMI, NMI, or whatever handler, then we know that it executed
-	 * a memory barrier when doing so.  So we don't need another one.
-	 */
-	if (curr != snap)
-		return 0;
-
-	/* We need the CPU to execute a memory barrier. */
-
-	return 1;
-}
-
-static void dyntick_save_progress_counter_sched(int cpu)
-{
-	struct rcu_dyntick_sched *rdssp = &per_cpu(rcu_dyntick_sched, cpu);
-
-	rdssp->sched_dynticks_snap = rdssp->dynticks;
-}
-
-static int rcu_qsctr_inc_needed_dyntick(int cpu)
-{
-	long curr;
-	long snap;
-	struct rcu_dyntick_sched *rdssp = &per_cpu(rcu_dyntick_sched, cpu);
-
-	curr = rdssp->dynticks;
-	snap = rdssp->sched_dynticks_snap;
-	smp_mb(); /* force ordering with cpu entering/leaving dynticks. */
-
-	/*
-	 * If the CPU remained in dynticks mode for the entire time
-	 * and didn't take any interrupts, NMIs, SMIs, or whatever,
-	 * then it cannot be in the middle of an rcu_read_lock(), so
-	 * the next rcu_read_lock() it executes must use the new value
-	 * of the counter.  Therefore, this CPU has been in a quiescent
-	 * state the entire time, and we don't need to wait for it.
-	 */
-
-	if ((curr == snap) && ((curr & 0x1) == 0))
-		return 0;
-
-	/*
-	 * If the CPU passed through or entered a dynticks idle phase with
-	 * no active irq handlers, then, as above, this CPU has already
-	 * passed through a quiescent state.
-	 */
-
-	if ((curr - snap) > 2 || (snap & 0x1) == 0)
-		return 0;
-
-	/* We need this CPU to go through a quiescent state. */
-
-	return 1;
-}
-
-#else /* !CONFIG_NO_HZ */
-
-# define dyntick_save_progress_counter(cpu)		do { } while (0)
-# define rcu_try_flip_waitack_needed(cpu)		(1)
-# define rcu_try_flip_waitmb_needed(cpu)		(1)
-
-# define dyntick_save_progress_counter_sched(cpu)	do { } while (0)
-# define rcu_qsctr_inc_needed_dyntick(cpu)		(1)
-
-#endif /* CONFIG_NO_HZ */
-
-static void save_qsctr_sched(int cpu)
-{
-	struct rcu_dyntick_sched *rdssp = &per_cpu(rcu_dyntick_sched, cpu);
-
-	rdssp->sched_qs_snap = rdssp->sched_qs;
-}
-
-static inline int rcu_qsctr_inc_needed(int cpu)
-{
-	struct rcu_dyntick_sched *rdssp = &per_cpu(rcu_dyntick_sched, cpu);
-
-	/*
-	 * If there has been a quiescent state, no more need to wait
-	 * on this CPU.
-	 */
-
-	if (rdssp->sched_qs != rdssp->sched_qs_snap) {
-		smp_mb(); /* force ordering with cpu entering schedule(). */
-		return 0;
-	}
-
-	/* We need this CPU to go through a quiescent state. */
-
-	return 1;
-}
-
-/*
- * Get here when RCU is idle.  Decide whether we need to
- * move out of idle state, and return non-zero if so.
- * "Straightforward" approach for the moment, might later
- * use callback-list lengths, grace-period duration, or
- * some such to determine when to exit idle state.
- * Might also need a pre-idle test that does not acquire
- * the lock, but let's get the simple case working first...
- */
-
-static int
-rcu_try_flip_idle(void)
-{
-	int cpu;
-
-	RCU_TRACE_ME(rcupreempt_trace_try_flip_i1);
-	if (!rcu_pending(smp_processor_id())) {
-		RCU_TRACE_ME(rcupreempt_trace_try_flip_ie1);
-		return 0;
-	}
-
-	/*
-	 * Do the flip.
-	 */
-
-	RCU_TRACE_ME(rcupreempt_trace_try_flip_g1);
-	rcu_ctrlblk.completed++;  /* stands in for rcu_try_flip_g2 */
-
-	/*
-	 * Need a memory barrier so that other CPUs see the new
-	 * counter value before they see the subsequent change of all
-	 * the rcu_flip_flag instances to rcu_flipped.
-	 */
-
-	smp_mb();	/* see above block comment. */
-
-	/* Now ask each CPU for acknowledgement of the flip. */
-
-	for_each_cpu(cpu, to_cpumask(rcu_cpu_online_map)) {
-		per_cpu(rcu_flip_flag, cpu) = rcu_flipped;
-		dyntick_save_progress_counter(cpu);
-	}
-
-	return 1;
-}
-
-/*
- * Wait for CPUs to acknowledge the flip.
- */
-
-static int
-rcu_try_flip_waitack(void)
-{
-	int cpu;
-
-	RCU_TRACE_ME(rcupreempt_trace_try_flip_a1);
-	for_each_cpu(cpu, to_cpumask(rcu_cpu_online_map))
-		if (rcu_try_flip_waitack_needed(cpu) &&
-		    per_cpu(rcu_flip_flag, cpu) != rcu_flip_seen) {
-			RCU_TRACE_ME(rcupreempt_trace_try_flip_ae1);
-			return 0;
-		}
-
-	/*
-	 * Make sure our checks above don't bleed into subsequent
-	 * waiting for the sum of the counters to reach zero.
-	 */
-
-	smp_mb();	/* see above block comment. */
-	RCU_TRACE_ME(rcupreempt_trace_try_flip_a2);
-	return 1;
-}
-
-/*
- * Wait for collective ``last'' counter to reach zero,
- * then tell all CPUs to do an end-of-grace-period memory barrier.
- */
-
-static int
-rcu_try_flip_waitzero(void)
-{
-	int cpu;
-	int lastidx = !(rcu_ctrlblk.completed & 0x1);
-	int sum = 0;
-
-	/* Check to see if the sum of the "last" counters is zero. */
-
-	RCU_TRACE_ME(rcupreempt_trace_try_flip_z1);
-	for_each_cpu(cpu, to_cpumask(rcu_cpu_online_map))
-		sum += RCU_DATA_CPU(cpu)->rcu_flipctr[lastidx];
-	if (sum != 0) {
-		RCU_TRACE_ME(rcupreempt_trace_try_flip_ze1);
-		return 0;
-	}
-
-	/*
-	 * This ensures that the other CPUs see the call for
-	 * memory barriers -after- the sum to zero has been
-	 * detected here
-	 */
-	smp_mb();  /*  ^^^^^^^^^^^^ */
-
-	/* Call for a memory barrier from each CPU. */
-	for_each_cpu(cpu, to_cpumask(rcu_cpu_online_map)) {
-		per_cpu(rcu_mb_flag, cpu) = rcu_mb_needed;
-		dyntick_save_progress_counter(cpu);
-	}
-
-	RCU_TRACE_ME(rcupreempt_trace_try_flip_z2);
-	return 1;
-}
-
-/*
- * Wait for all CPUs to do their end-of-grace-period memory barrier.
- * Return 0 once all CPUs have done so.
- */
-
-static int
-rcu_try_flip_waitmb(void)
-{
-	int cpu;
-
-	RCU_TRACE_ME(rcupreempt_trace_try_flip_m1);
-	for_each_cpu(cpu, to_cpumask(rcu_cpu_online_map))
-		if (rcu_try_flip_waitmb_needed(cpu) &&
-		    per_cpu(rcu_mb_flag, cpu) != rcu_mb_done) {
-			RCU_TRACE_ME(rcupreempt_trace_try_flip_me1);
-			return 0;
-		}
-
-	smp_mb(); /* Ensure that the above checks precede any following flip. */
-	RCU_TRACE_ME(rcupreempt_trace_try_flip_m2);
-	return 1;
-}
-
-/*
- * Attempt a single flip of the counters.  Remember, a single flip does
- * -not- constitute a grace period.  Instead, the interval between
- * at least GP_STAGES consecutive flips is a grace period.
- *
- * If anyone is nuts enough to run this CONFIG_PREEMPT_RCU implementation
- * on a large SMP, they might want to use a hierarchical organization of
- * the per-CPU-counter pairs.
- */
-static void rcu_try_flip(void)
-{
-	unsigned long flags;
-
-	RCU_TRACE_ME(rcupreempt_trace_try_flip_1);
-	if (unlikely(!spin_trylock_irqsave(&rcu_ctrlblk.fliplock, flags))) {
-		RCU_TRACE_ME(rcupreempt_trace_try_flip_e1);
-		return;
-	}
-
-	/*
-	 * Take the next transition(s) through the RCU grace-period
-	 * flip-counter state machine.
-	 */
-
-	switch (rcu_ctrlblk.rcu_try_flip_state) {
-	case rcu_try_flip_idle_state:
-		if (rcu_try_flip_idle())
-			rcu_ctrlblk.rcu_try_flip_state =
-				rcu_try_flip_waitack_state;
-		break;
-	case rcu_try_flip_waitack_state:
-		if (rcu_try_flip_waitack())
-			rcu_ctrlblk.rcu_try_flip_state =
-				rcu_try_flip_waitzero_state;
-		break;
-	case rcu_try_flip_waitzero_state:
-		if (rcu_try_flip_waitzero())
-			rcu_ctrlblk.rcu_try_flip_state =
-				rcu_try_flip_waitmb_state;
-		break;
-	case rcu_try_flip_waitmb_state:
-		if (rcu_try_flip_waitmb())
-			rcu_ctrlblk.rcu_try_flip_state =
-				rcu_try_flip_idle_state;
-	}
-	spin_unlock_irqrestore(&rcu_ctrlblk.fliplock, flags);
-}
-
-/*
- * Check to see if this CPU needs to do a memory barrier in order to
- * ensure that any prior RCU read-side critical sections have committed
- * their counter manipulations and critical-section memory references
- * before declaring the grace period to be completed.
- */
-static void rcu_check_mb(int cpu)
-{
-	if (per_cpu(rcu_mb_flag, cpu) == rcu_mb_needed) {
-		smp_mb();  /* Ensure RCU read-side accesses are visible. */
-		per_cpu(rcu_mb_flag, cpu) = rcu_mb_done;
-	}
-}
-
-void rcu_check_callbacks(int cpu, int user)
-{
-	unsigned long flags;
-	struct rcu_data *rdp = RCU_DATA_CPU(cpu);
-
-	/*
-	 * If this CPU took its interrupt from user mode or from the
-	 * idle loop, and this is not a nested interrupt, then
-	 * this CPU has to have exited all prior preept-disable
-	 * sections of code.  So increment the counter to note this.
-	 *
-	 * The memory barrier is needed to handle the case where
-	 * writes from a preempt-disable section of code get reordered
-	 * into schedule() by this CPU's write buffer.  So the memory
-	 * barrier makes sure that the rcu_qsctr_inc() is seen by other
-	 * CPUs to happen after any such write.
-	 */
-
-	if (user ||
-	    (idle_cpu(cpu) && !in_softirq() &&
-	     hardirq_count() <= (1 << HARDIRQ_SHIFT))) {
-		smp_mb();	/* Guard against aggressive schedule(). */
-	     	rcu_qsctr_inc(cpu);
-	}
-
-	rcu_check_mb(cpu);
-	if (rcu_ctrlblk.completed == rdp->completed)
-		rcu_try_flip();
-	spin_lock_irqsave(&rdp->lock, flags);
-	RCU_TRACE_RDP(rcupreempt_trace_check_callbacks, rdp);
-	__rcu_advance_callbacks(rdp);
-	if (rdp->donelist == NULL) {
-		spin_unlock_irqrestore(&rdp->lock, flags);
-	} else {
-		spin_unlock_irqrestore(&rdp->lock, flags);
-		raise_softirq(RCU_SOFTIRQ);
-	}
-}
-
-/*
- * Needed by dynticks, to make sure all RCU processing has finished
- * when we go idle:
- */
-void rcu_advance_callbacks(int cpu, int user)
-{
-	unsigned long flags;
-	struct rcu_data *rdp = RCU_DATA_CPU(cpu);
-
-	if (rcu_ctrlblk.completed == rdp->completed) {
-		rcu_try_flip();
-		if (rcu_ctrlblk.completed == rdp->completed)
-			return;
-	}
-	spin_lock_irqsave(&rdp->lock, flags);
-	RCU_TRACE_RDP(rcupreempt_trace_check_callbacks, rdp);
-	__rcu_advance_callbacks(rdp);
-	spin_unlock_irqrestore(&rdp->lock, flags);
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-#define rcu_offline_cpu_enqueue(srclist, srctail, dstlist, dsttail) do { \
-		*dsttail = srclist; \
-		if (srclist != NULL) { \
-			dsttail = srctail; \
-			srclist = NULL; \
-			srctail = &srclist;\
-		} \
-	} while (0)
-
-void rcu_offline_cpu(int cpu)
-{
-	int i;
-	struct rcu_head *list = NULL;
-	unsigned long flags;
-	struct rcu_data *rdp = RCU_DATA_CPU(cpu);
-	struct rcu_head *schedlist = NULL;
-	struct rcu_head **schedtail = &schedlist;
-	struct rcu_head **tail = &list;
-
-	/*
-	 * Remove all callbacks from the newly dead CPU, retaining order.
-	 * Otherwise rcu_barrier() will fail
-	 */
-
-	spin_lock_irqsave(&rdp->lock, flags);
-	rcu_offline_cpu_enqueue(rdp->donelist, rdp->donetail, list, tail);
-	for (i = GP_STAGES - 1; i >= 0; i--)
-		rcu_offline_cpu_enqueue(rdp->waitlist[i], rdp->waittail[i],
-						list, tail);
-	rcu_offline_cpu_enqueue(rdp->nextlist, rdp->nexttail, list, tail);
-	rcu_offline_cpu_enqueue(rdp->waitschedlist, rdp->waitschedtail,
-				schedlist, schedtail);
-	rcu_offline_cpu_enqueue(rdp->nextschedlist, rdp->nextschedtail,
-				schedlist, schedtail);
-	rdp->rcu_sched_sleeping = 0;
-	spin_unlock_irqrestore(&rdp->lock, flags);
-	rdp->waitlistcount = 0;
-
-	/* Disengage the newly dead CPU from the grace-period computation. */
-
-	spin_lock_irqsave(&rcu_ctrlblk.fliplock, flags);
-	rcu_check_mb(cpu);
-	if (per_cpu(rcu_flip_flag, cpu) == rcu_flipped) {
-		smp_mb();  /* Subsequent counter accesses must see new value */
-		per_cpu(rcu_flip_flag, cpu) = rcu_flip_seen;
-		smp_mb();  /* Subsequent RCU read-side critical sections */
-			   /*  seen -after- acknowledgement. */
-	}
-
-	RCU_DATA_ME()->rcu_flipctr[0] += RCU_DATA_CPU(cpu)->rcu_flipctr[0];
-	RCU_DATA_ME()->rcu_flipctr[1] += RCU_DATA_CPU(cpu)->rcu_flipctr[1];
-
-	RCU_DATA_CPU(cpu)->rcu_flipctr[0] = 0;
-	RCU_DATA_CPU(cpu)->rcu_flipctr[1] = 0;
-
-	cpumask_clear_cpu(cpu, to_cpumask(rcu_cpu_online_map));
-
-	spin_unlock_irqrestore(&rcu_ctrlblk.fliplock, flags);
-
-	/*
-	 * Place the removed callbacks on the current CPU's queue.
-	 * Make them all start a new grace period: simple approach,
-	 * in theory could starve a given set of callbacks, but
-	 * you would need to be doing some serious CPU hotplugging
-	 * to make this happen.  If this becomes a problem, adding
-	 * a synchronize_rcu() to the hotplug path would be a simple
-	 * fix.
-	 */
-
-	local_irq_save(flags);  /* disable preempt till we know what lock. */
-	rdp = RCU_DATA_ME();
-	spin_lock(&rdp->lock);
-	*rdp->nexttail = list;
-	if (list)
-		rdp->nexttail = tail;
-	*rdp->nextschedtail = schedlist;
-	if (schedlist)
-		rdp->nextschedtail = schedtail;
-	spin_unlock_irqrestore(&rdp->lock, flags);
-}
-
-#else /* #ifdef CONFIG_HOTPLUG_CPU */
-
-void rcu_offline_cpu(int cpu)
-{
-}
-
-#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
-
-void __cpuinit rcu_online_cpu(int cpu)
-{
-	unsigned long flags;
-	struct rcu_data *rdp;
-
-	spin_lock_irqsave(&rcu_ctrlblk.fliplock, flags);
-	cpumask_set_cpu(cpu, to_cpumask(rcu_cpu_online_map));
-	spin_unlock_irqrestore(&rcu_ctrlblk.fliplock, flags);
-
-	/*
-	 * The rcu_sched grace-period processing might have bypassed
-	 * this CPU, given that it was not in the rcu_cpu_online_map
-	 * when the grace-period scan started.  This means that the
-	 * grace-period task might sleep.  So make sure that if this
-	 * should happen, the first callback posted to this CPU will
-	 * wake up the grace-period task if need be.
-	 */
-
-	rdp = RCU_DATA_CPU(cpu);
-	spin_lock_irqsave(&rdp->lock, flags);
-	rdp->rcu_sched_sleeping = 1;
-	spin_unlock_irqrestore(&rdp->lock, flags);
-}
-
-static void rcu_process_callbacks(struct softirq_action *unused)
-{
-	unsigned long flags;
-	struct rcu_head *next, *list;
-	struct rcu_data *rdp;
-
-	local_irq_save(flags);
-	rdp = RCU_DATA_ME();
-	spin_lock(&rdp->lock);
-	list = rdp->donelist;
-	if (list == NULL) {
-		spin_unlock_irqrestore(&rdp->lock, flags);
-		return;
-	}
-	rdp->donelist = NULL;
-	rdp->donetail = &rdp->donelist;
-	RCU_TRACE_RDP(rcupreempt_trace_done_remove, rdp);
-	spin_unlock_irqrestore(&rdp->lock, flags);
-	while (list) {
-		next = list->next;
-		list->func(list);
-		list = next;
-		RCU_TRACE_ME(rcupreempt_trace_invoke);
-	}
-}
-
-void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
-{
-	unsigned long flags;
-	struct rcu_data *rdp;
-
-	head->func = func;
-	head->next = NULL;
-	local_irq_save(flags);
-	rdp = RCU_DATA_ME();
-	spin_lock(&rdp->lock);
-	__rcu_advance_callbacks(rdp);
-	*rdp->nexttail = head;
-	rdp->nexttail = &head->next;
-	RCU_TRACE_RDP(rcupreempt_trace_next_add, rdp);
-	spin_unlock_irqrestore(&rdp->lock, flags);
-}
-EXPORT_SYMBOL_GPL(call_rcu);
-
-void call_rcu_sched(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
-{
-	unsigned long flags;
-	struct rcu_data *rdp;
-	int wake_gp = 0;
-
-	head->func = func;
-	head->next = NULL;
-	local_irq_save(flags);
-	rdp = RCU_DATA_ME();
-	spin_lock(&rdp->lock);
-	*rdp->nextschedtail = head;
-	rdp->nextschedtail = &head->next;
-	if (rdp->rcu_sched_sleeping) {
-
-		/* Grace-period processing might be sleeping... */
-
-		rdp->rcu_sched_sleeping = 0;
-		wake_gp = 1;
-	}
-	spin_unlock_irqrestore(&rdp->lock, flags);
-	if (wake_gp) {
-
-		/* Wake up grace-period processing, unless someone beat us. */
-
-		spin_lock_irqsave(&rcu_ctrlblk.schedlock, flags);
-		if (rcu_ctrlblk.sched_sleep != rcu_sched_sleeping)
-			wake_gp = 0;
-		rcu_ctrlblk.sched_sleep = rcu_sched_not_sleeping;
-		spin_unlock_irqrestore(&rcu_ctrlblk.schedlock, flags);
-		if (wake_gp)
-			wake_up_interruptible(&rcu_ctrlblk.sched_wq);
-	}
-}
-EXPORT_SYMBOL_GPL(call_rcu_sched);
-
-/*
- * Wait until all currently running preempt_disable() code segments
- * (including hardware-irq-disable segments) complete.  Note that
- * in -rt this does -not- necessarily result in all currently executing
- * interrupt -handlers- having completed.
- */
-void __synchronize_sched(void)
-{
-	struct rcu_synchronize rcu;
-
-	if (num_online_cpus() == 1)
-		return;  /* blocking is gp if only one CPU! */
-
-	init_completion(&rcu.completion);
-	/* Will wake me after RCU finished. */
-	call_rcu_sched(&rcu.head, wakeme_after_rcu);
-	/* Wait for it. */
-	wait_for_completion(&rcu.completion);
-}
-EXPORT_SYMBOL_GPL(__synchronize_sched);
-
-/*
- * kthread function that manages call_rcu_sched grace periods.
- */
-static int rcu_sched_grace_period(void *arg)
-{
-	int couldsleep;		/* might sleep after current pass. */
-	int couldsleepnext = 0; /* might sleep after next pass. */
-	int cpu;
-	unsigned long flags;
-	struct rcu_data *rdp;
-	int ret;
-
-	/*
-	 * Each pass through the following loop handles one
-	 * rcu_sched grace period cycle.
-	 */
-	do {
-		/* Save each CPU's current state. */
-
-		for_each_online_cpu(cpu) {
-			dyntick_save_progress_counter_sched(cpu);
-			save_qsctr_sched(cpu);
-		}
-
-		/*
-		 * Sleep for about an RCU grace-period's worth to
-		 * allow better batching and to consume less CPU.
-		 */
-		schedule_timeout_interruptible(RCU_SCHED_BATCH_TIME);
-
-		/*
-		 * If there was nothing to do last time, prepare to
-		 * sleep at the end of the current grace period cycle.
-		 */
-		couldsleep = couldsleepnext;
-		couldsleepnext = 1;
-		if (couldsleep) {
-			spin_lock_irqsave(&rcu_ctrlblk.schedlock, flags);
-			rcu_ctrlblk.sched_sleep = rcu_sched_sleep_prep;
-			spin_unlock_irqrestore(&rcu_ctrlblk.schedlock, flags);
-		}
-
-		/*
-		 * Wait on each CPU in turn to have either visited
-		 * a quiescent state or been in dynticks-idle mode.
-		 */
-		for_each_online_cpu(cpu) {
-			while (rcu_qsctr_inc_needed(cpu) &&
-			       rcu_qsctr_inc_needed_dyntick(cpu)) {
-				/* resched_cpu(cpu); @@@ */
-				schedule_timeout_interruptible(1);
-			}
-		}
-
-		/* Advance callbacks for each CPU.  */
-
-		for_each_online_cpu(cpu) {
-
-			rdp = RCU_DATA_CPU(cpu);
-			spin_lock_irqsave(&rdp->lock, flags);
-
-			/*
-			 * We are running on this CPU irq-disabled, so no
-			 * CPU can go offline until we re-enable irqs.
-			 * The current CPU might have already gone
-			 * offline (between the for_each_offline_cpu and
-			 * the spin_lock_irqsave), but in that case all its
-			 * callback lists will be empty, so no harm done.
-			 *
-			 * Advance the callbacks!  We share normal RCU's
-			 * donelist, since callbacks are invoked the
-			 * same way in either case.
-			 */
-			if (rdp->waitschedlist != NULL) {
-				*rdp->donetail = rdp->waitschedlist;
-				rdp->donetail = rdp->waitschedtail;
-
-				/*
-				 * Next rcu_check_callbacks() will
-				 * do the required raise_softirq().
-				 */
-			}
-			if (rdp->nextschedlist != NULL) {
-				rdp->waitschedlist = rdp->nextschedlist;
-				rdp->waitschedtail = rdp->nextschedtail;
-				couldsleep = 0;
-				couldsleepnext = 0;
-			} else {
-				rdp->waitschedlist = NULL;
-				rdp->waitschedtail = &rdp->waitschedlist;
-			}
-			rdp->nextschedlist = NULL;
-			rdp->nextschedtail = &rdp->nextschedlist;
-
-			/* Mark sleep intention. */
-
-			rdp->rcu_sched_sleeping = couldsleep;
-
-			spin_unlock_irqrestore(&rdp->lock, flags);
-		}
-
-		/* If we saw callbacks on the last scan, go deal with them. */
-
-		if (!couldsleep)
-			continue;
-
-		/* Attempt to block... */
-
-		spin_lock_irqsave(&rcu_ctrlblk.schedlock, flags);
-		if (rcu_ctrlblk.sched_sleep != rcu_sched_sleep_prep) {
-
-			/*
-			 * Someone posted a callback after we scanned.
-			 * Go take care of it.
-			 */
-			spin_unlock_irqrestore(&rcu_ctrlblk.schedlock, flags);
-			couldsleepnext = 0;
-			continue;
-		}
-
-		/* Block until the next person posts a callback. */
-
-		rcu_ctrlblk.sched_sleep = rcu_sched_sleeping;
-		spin_unlock_irqrestore(&rcu_ctrlblk.schedlock, flags);
-		ret = 0; /* unused */
-		__wait_event_interruptible(rcu_ctrlblk.sched_wq,
-			rcu_ctrlblk.sched_sleep != rcu_sched_sleeping,
-			ret);
-
-		couldsleepnext = 0;
-
-	} while (!kthread_should_stop());
-
-	return (0);
-}
-
-/*
- * Check to see if any future RCU-related work will need to be done
- * by the current CPU, even if none need be done immediately, returning
- * 1 if so.  Assumes that notifiers would take care of handling any
- * outstanding requests from the RCU core.
- *
- * This function is part of the RCU implementation; it is -not-
- * an exported member of the RCU API.
- */
-int rcu_needs_cpu(int cpu)
-{
-	struct rcu_data *rdp = RCU_DATA_CPU(cpu);
-
-	return (rdp->donelist != NULL ||
-		!!rdp->waitlistcount ||
-		rdp->nextlist != NULL ||
-		rdp->nextschedlist != NULL ||
-		rdp->waitschedlist != NULL);
-}
-
-int rcu_pending(int cpu)
-{
-	struct rcu_data *rdp = RCU_DATA_CPU(cpu);
-
-	/* The CPU has at least one callback queued somewhere. */
-
-	if (rdp->donelist != NULL ||
-	    !!rdp->waitlistcount ||
-	    rdp->nextlist != NULL ||
-	    rdp->nextschedlist != NULL ||
-	    rdp->waitschedlist != NULL)
-		return 1;
-
-	/* The RCU core needs an acknowledgement from this CPU. */
-
-	if ((per_cpu(rcu_flip_flag, cpu) == rcu_flipped) ||
-	    (per_cpu(rcu_mb_flag, cpu) == rcu_mb_needed))
-		return 1;
-
-	/* This CPU has fallen behind the global grace-period number. */
-
-	if (rdp->completed != rcu_ctrlblk.completed)
-		return 1;
-
-	/* Nothing needed from this CPU. */
-
-	return 0;
-}
-
-static int __cpuinit rcu_cpu_notify(struct notifier_block *self,
-				unsigned long action, void *hcpu)
-{
-	long cpu = (long)hcpu;
-
-	switch (action) {
-	case CPU_UP_PREPARE:
-	case CPU_UP_PREPARE_FROZEN:
-		rcu_online_cpu(cpu);
-		break;
-	case CPU_UP_CANCELED:
-	case CPU_UP_CANCELED_FROZEN:
-	case CPU_DEAD:
-	case CPU_DEAD_FROZEN:
-		rcu_offline_cpu(cpu);
-		break;
-	default:
-		break;
-	}
-	return NOTIFY_OK;
-}
-
-static struct notifier_block __cpuinitdata rcu_nb = {
-	.notifier_call = rcu_cpu_notify,
-};
-
-void __init __rcu_init(void)
-{
-	int cpu;
-	int i;
-	struct rcu_data *rdp;
-
-	printk(KERN_NOTICE "Preemptible RCU implementation.\n");
-	for_each_possible_cpu(cpu) {
-		rdp = RCU_DATA_CPU(cpu);
-		spin_lock_init(&rdp->lock);
-		rdp->completed = 0;
-		rdp->waitlistcount = 0;
-		rdp->nextlist = NULL;
-		rdp->nexttail = &rdp->nextlist;
-		for (i = 0; i < GP_STAGES; i++) {
-			rdp->waitlist[i] = NULL;
-			rdp->waittail[i] = &rdp->waitlist[i];
-		}
-		rdp->donelist = NULL;
-		rdp->donetail = &rdp->donelist;
-		rdp->rcu_flipctr[0] = 0;
-		rdp->rcu_flipctr[1] = 0;
-		rdp->nextschedlist = NULL;
-		rdp->nextschedtail = &rdp->nextschedlist;
-		rdp->waitschedlist = NULL;
-		rdp->waitschedtail = &rdp->waitschedlist;
-		rdp->rcu_sched_sleeping = 0;
-	}
-	register_cpu_notifier(&rcu_nb);
-
-	/*
-	 * We don't need protection against CPU-Hotplug here
-	 * since
-	 * a) If a CPU comes online while we are iterating over the
-	 *    cpu_online_mask below, we would only end up making a
-	 *    duplicate call to rcu_online_cpu() which sets the corresponding
-	 *    CPU's mask in the rcu_cpu_online_map.
-	 *
-	 * b) A CPU cannot go offline at this point in time since the user
-	 *    does not have access to the sysfs interface, nor do we
-	 *    suspend the system.
-	 */
-	for_each_online_cpu(cpu)
-		rcu_cpu_notify(&rcu_nb, CPU_UP_PREPARE,	(void *)(long) cpu);
-
-	open_softirq(RCU_SOFTIRQ, rcu_process_callbacks);
-}
-
-/*
- * Late-boot-time RCU initialization that must wait until after scheduler
- * has been initialized.
- */
-void __init rcu_init_sched(void)
-{
-	rcu_sched_grace_period_task = kthread_run(rcu_sched_grace_period,
-						  NULL,
-						  "rcu_sched_grace_period");
-	WARN_ON(IS_ERR(rcu_sched_grace_period_task));
-}
-
-#ifdef CONFIG_RCU_TRACE
-long *rcupreempt_flipctr(int cpu)
-{
-	return &RCU_DATA_CPU(cpu)->rcu_flipctr[0];
-}
-EXPORT_SYMBOL_GPL(rcupreempt_flipctr);
-
-int rcupreempt_flip_flag(int cpu)
-{
-	return per_cpu(rcu_flip_flag, cpu);
-}
-EXPORT_SYMBOL_GPL(rcupreempt_flip_flag);
-
-int rcupreempt_mb_flag(int cpu)
-{
-	return per_cpu(rcu_mb_flag, cpu);
-}
-EXPORT_SYMBOL_GPL(rcupreempt_mb_flag);
-
-char *rcupreempt_try_flip_state_name(void)
-{
-	return rcu_try_flip_state_names[rcu_ctrlblk.rcu_try_flip_state];
-}
-EXPORT_SYMBOL_GPL(rcupreempt_try_flip_state_name);
-
-struct rcupreempt_trace *rcupreempt_trace_cpu(int cpu)
-{
-	struct rcu_data *rdp = RCU_DATA_CPU(cpu);
-
-	return &rdp->trace;
-}
-EXPORT_SYMBOL_GPL(rcupreempt_trace_cpu);
-
-#endif /* #ifdef RCU_TRACE */
diff --git a/kernel/rcupreempt_trace.c b/kernel/rcupreempt_trace.c
deleted file mode 100644
index 7c2665c..0000000
--- a/kernel/rcupreempt_trace.c
+++ /dev/null
@@ -1,334 +0,0 @@
-/*
- * Read-Copy Update tracing for realtime implementation
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
- * Copyright IBM Corporation, 2006
- *
- * Papers:  http://www.rdrop.com/users/paulmck/RCU
- *
- * For detailed explanation of Read-Copy Update mechanism see -
- * 		Documentation/RCU/ *.txt
- *
- */
-#include <linux/types.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/spinlock.h>
-#include <linux/smp.h>
-#include <linux/rcupdate.h>
-#include <linux/interrupt.h>
-#include <linux/sched.h>
-#include <asm/atomic.h>
-#include <linux/bitops.h>
-#include <linux/module.h>
-#include <linux/completion.h>
-#include <linux/moduleparam.h>
-#include <linux/percpu.h>
-#include <linux/notifier.h>
-#include <linux/cpu.h>
-#include <linux/mutex.h>
-#include <linux/rcupreempt_trace.h>
-#include <linux/debugfs.h>
-
-static struct mutex rcupreempt_trace_mutex;
-static char *rcupreempt_trace_buf;
-#define RCUPREEMPT_TRACE_BUF_SIZE 4096
-
-void rcupreempt_trace_move2done(struct rcupreempt_trace *trace)
-{
-	trace->done_length += trace->wait_length;
-	trace->done_add += trace->wait_length;
-	trace->wait_length = 0;
-}
-void rcupreempt_trace_move2wait(struct rcupreempt_trace *trace)
-{
-	trace->wait_length += trace->next_length;
-	trace->wait_add += trace->next_length;
-	trace->next_length = 0;
-}
-void rcupreempt_trace_try_flip_1(struct rcupreempt_trace *trace)
-{
-	atomic_inc(&trace->rcu_try_flip_1);
-}
-void rcupreempt_trace_try_flip_e1(struct rcupreempt_trace *trace)
-{
-	atomic_inc(&trace->rcu_try_flip_e1);
-}
-void rcupreempt_trace_try_flip_i1(struct rcupreempt_trace *trace)
-{
-	trace->rcu_try_flip_i1++;
-}
-void rcupreempt_trace_try_flip_ie1(struct rcupreempt_trace *trace)
-{
-	trace->rcu_try_flip_ie1++;
-}
-void rcupreempt_trace_try_flip_g1(struct rcupreempt_trace *trace)
-{
-	trace->rcu_try_flip_g1++;
-}
-void rcupreempt_trace_try_flip_a1(struct rcupreempt_trace *trace)
-{
-	trace->rcu_try_flip_a1++;
-}
-void rcupreempt_trace_try_flip_ae1(struct rcupreempt_trace *trace)
-{
-	trace->rcu_try_flip_ae1++;
-}
-void rcupreempt_trace_try_flip_a2(struct rcupreempt_trace *trace)
-{
-	trace->rcu_try_flip_a2++;
-}
-void rcupreempt_trace_try_flip_z1(struct rcupreempt_trace *trace)
-{
-	trace->rcu_try_flip_z1++;
-}
-void rcupreempt_trace_try_flip_ze1(struct rcupreempt_trace *trace)
-{
-	trace->rcu_try_flip_ze1++;
-}
-void rcupreempt_trace_try_flip_z2(struct rcupreempt_trace *trace)
-{
-	trace->rcu_try_flip_z2++;
-}
-void rcupreempt_trace_try_flip_m1(struct rcupreempt_trace *trace)
-{
-	trace->rcu_try_flip_m1++;
-}
-void rcupreempt_trace_try_flip_me1(struct rcupreempt_trace *trace)
-{
-	trace->rcu_try_flip_me1++;
-}
-void rcupreempt_trace_try_flip_m2(struct rcupreempt_trace *trace)
-{
-	trace->rcu_try_flip_m2++;
-}
-void rcupreempt_trace_check_callbacks(struct rcupreempt_trace *trace)
-{
-	trace->rcu_check_callbacks++;
-}
-void rcupreempt_trace_done_remove(struct rcupreempt_trace *trace)
-{
-	trace->done_remove += trace->done_length;
-	trace->done_length = 0;
-}
-void rcupreempt_trace_invoke(struct rcupreempt_trace *trace)
-{
-	atomic_inc(&trace->done_invoked);
-}
-void rcupreempt_trace_next_add(struct rcupreempt_trace *trace)
-{
-	trace->next_add++;
-	trace->next_length++;
-}
-
-static void rcupreempt_trace_sum(struct rcupreempt_trace *sp)
-{
-	struct rcupreempt_trace *cp;
-	int cpu;
-
-	memset(sp, 0, sizeof(*sp));
-	for_each_possible_cpu(cpu) {
-		cp = rcupreempt_trace_cpu(cpu);
-		sp->next_length += cp->next_length;
-		sp->next_add += cp->next_add;
-		sp->wait_length += cp->wait_length;
-		sp->wait_add += cp->wait_add;
-		sp->done_length += cp->done_length;
-		sp->done_add += cp->done_add;
-		sp->done_remove += cp->done_remove;
-		atomic_add(atomic_read(&cp->done_invoked), &sp->done_invoked);
-		sp->rcu_check_callbacks += cp->rcu_check_callbacks;
-		atomic_add(atomic_read(&cp->rcu_try_flip_1),
-			   &sp->rcu_try_flip_1);
-		atomic_add(atomic_read(&cp->rcu_try_flip_e1),
-			   &sp->rcu_try_flip_e1);
-		sp->rcu_try_flip_i1 += cp->rcu_try_flip_i1;
-		sp->rcu_try_flip_ie1 += cp->rcu_try_flip_ie1;
-		sp->rcu_try_flip_g1 += cp->rcu_try_flip_g1;
-		sp->rcu_try_flip_a1 += cp->rcu_try_flip_a1;
-		sp->rcu_try_flip_ae1 += cp->rcu_try_flip_ae1;
-		sp->rcu_try_flip_a2 += cp->rcu_try_flip_a2;
-		sp->rcu_try_flip_z1 += cp->rcu_try_flip_z1;
-		sp->rcu_try_flip_ze1 += cp->rcu_try_flip_ze1;
-		sp->rcu_try_flip_z2 += cp->rcu_try_flip_z2;
-		sp->rcu_try_flip_m1 += cp->rcu_try_flip_m1;
-		sp->rcu_try_flip_me1 += cp->rcu_try_flip_me1;
-		sp->rcu_try_flip_m2 += cp->rcu_try_flip_m2;
-	}
-}
-
-static ssize_t rcustats_read(struct file *filp, char __user *buffer,
-				size_t count, loff_t *ppos)
-{
-	struct rcupreempt_trace trace;
-	ssize_t bcount;
-	int cnt = 0;
-
-	rcupreempt_trace_sum(&trace);
-	mutex_lock(&rcupreempt_trace_mutex);
-	snprintf(&rcupreempt_trace_buf[cnt], RCUPREEMPT_TRACE_BUF_SIZE - cnt,
-		 "ggp=%ld rcc=%ld\n",
-		 rcu_batches_completed(),
-		 trace.rcu_check_callbacks);
-	snprintf(&rcupreempt_trace_buf[cnt], RCUPREEMPT_TRACE_BUF_SIZE - cnt,
-		 "na=%ld nl=%ld wa=%ld wl=%ld da=%ld dl=%ld dr=%ld di=%d\n"
-		 "1=%d e1=%d i1=%ld ie1=%ld g1=%ld a1=%ld ae1=%ld a2=%ld\n"
-		 "z1=%ld ze1=%ld z2=%ld m1=%ld me1=%ld m2=%ld\n",
-
-		 trace.next_add, trace.next_length,
-		 trace.wait_add, trace.wait_length,
-		 trace.done_add, trace.done_length,
-		 trace.done_remove, atomic_read(&trace.done_invoked),
-		 atomic_read(&trace.rcu_try_flip_1),
-		 atomic_read(&trace.rcu_try_flip_e1),
-		 trace.rcu_try_flip_i1, trace.rcu_try_flip_ie1,
-		 trace.rcu_try_flip_g1,
-		 trace.rcu_try_flip_a1, trace.rcu_try_flip_ae1,
-			 trace.rcu_try_flip_a2,
-		 trace.rcu_try_flip_z1, trace.rcu_try_flip_ze1,
-			 trace.rcu_try_flip_z2,
-		 trace.rcu_try_flip_m1, trace.rcu_try_flip_me1,
-			trace.rcu_try_flip_m2);
-	bcount = simple_read_from_buffer(buffer, count, ppos,
-			rcupreempt_trace_buf, strlen(rcupreempt_trace_buf));
-	mutex_unlock(&rcupreempt_trace_mutex);
-	return bcount;
-}
-
-static ssize_t rcugp_read(struct file *filp, char __user *buffer,
-				size_t count, loff_t *ppos)
-{
-	long oldgp = rcu_batches_completed();
-	ssize_t bcount;
-
-	mutex_lock(&rcupreempt_trace_mutex);
-	synchronize_rcu();
-	snprintf(rcupreempt_trace_buf, RCUPREEMPT_TRACE_BUF_SIZE,
-		"oldggp=%ld  newggp=%ld\n", oldgp, rcu_batches_completed());
-	bcount = simple_read_from_buffer(buffer, count, ppos,
-			rcupreempt_trace_buf, strlen(rcupreempt_trace_buf));
-	mutex_unlock(&rcupreempt_trace_mutex);
-	return bcount;
-}
-
-static ssize_t rcuctrs_read(struct file *filp, char __user *buffer,
-				size_t count, loff_t *ppos)
-{
-	int cnt = 0;
-	int cpu;
-	int f = rcu_batches_completed() & 0x1;
-	ssize_t bcount;
-
-	mutex_lock(&rcupreempt_trace_mutex);
-
-	cnt += snprintf(&rcupreempt_trace_buf[cnt], RCUPREEMPT_TRACE_BUF_SIZE,
-				"CPU last cur F M\n");
-	for_each_online_cpu(cpu) {
-		long *flipctr = rcupreempt_flipctr(cpu);
-		cnt += snprintf(&rcupreempt_trace_buf[cnt],
-				RCUPREEMPT_TRACE_BUF_SIZE - cnt,
-					"%3d %4ld %3ld %d %d\n",
-			       cpu,
-			       flipctr[!f],
-			       flipctr[f],
-			       rcupreempt_flip_flag(cpu),
-			       rcupreempt_mb_flag(cpu));
-	}
-	cnt += snprintf(&rcupreempt_trace_buf[cnt],
-			RCUPREEMPT_TRACE_BUF_SIZE - cnt,
-			"ggp = %ld, state = %s\n",
-			rcu_batches_completed(),
-			rcupreempt_try_flip_state_name());
-	cnt += snprintf(&rcupreempt_trace_buf[cnt],
-			RCUPREEMPT_TRACE_BUF_SIZE - cnt,
-			"\n");
-	bcount = simple_read_from_buffer(buffer, count, ppos,
-			rcupreempt_trace_buf, strlen(rcupreempt_trace_buf));
-	mutex_unlock(&rcupreempt_trace_mutex);
-	return bcount;
-}
-
-static struct file_operations rcustats_fops = {
-	.owner = THIS_MODULE,
-	.read = rcustats_read,
-};
-
-static struct file_operations rcugp_fops = {
-	.owner = THIS_MODULE,
-	.read = rcugp_read,
-};
-
-static struct file_operations rcuctrs_fops = {
-	.owner = THIS_MODULE,
-	.read = rcuctrs_read,
-};
-
-static struct dentry *rcudir, *statdir, *ctrsdir, *gpdir;
-static int rcupreempt_debugfs_init(void)
-{
-	rcudir = debugfs_create_dir("rcu", NULL);
-	if (!rcudir)
-		goto out;
-	statdir = debugfs_create_file("rcustats", 0444, rcudir,
-						NULL, &rcustats_fops);
-	if (!statdir)
-		goto free_out;
-
-	gpdir = debugfs_create_file("rcugp", 0444, rcudir, NULL, &rcugp_fops);
-	if (!gpdir)
-		goto free_out;
-
-	ctrsdir = debugfs_create_file("rcuctrs", 0444, rcudir,
-						NULL, &rcuctrs_fops);
-	if (!ctrsdir)
-		goto free_out;
-	return 0;
-free_out:
-	if (statdir)
-		debugfs_remove(statdir);
-	if (gpdir)
-		debugfs_remove(gpdir);
-	debugfs_remove(rcudir);
-out:
-	return 1;
-}
-
-static int __init rcupreempt_trace_init(void)
-{
-	int ret;
-
-	mutex_init(&rcupreempt_trace_mutex);
-	rcupreempt_trace_buf = kmalloc(RCUPREEMPT_TRACE_BUF_SIZE, GFP_KERNEL);
-	if (!rcupreempt_trace_buf)
-		return 1;
-	ret = rcupreempt_debugfs_init();
-	if (ret)
-		kfree(rcupreempt_trace_buf);
-	return ret;
-}
-
-static void __exit rcupreempt_trace_cleanup(void)
-{
-	debugfs_remove(statdir);
-	debugfs_remove(gpdir);
-	debugfs_remove(ctrsdir);
-	debugfs_remove(rcudir);
-	kfree(rcupreempt_trace_buf);
-}
-
-
-module_init(rcupreempt_trace_init);
-module_exit(rcupreempt_trace_cleanup);
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index 9b4a975..233768f 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -18,7 +18,7 @@
  * Copyright (C) IBM Corporation, 2005, 2006
  *
  * Authors: Paul E. McKenney <paulmck@us.ibm.com>
- *          Josh Triplett <josh@freedesktop.org>
+ *	  Josh Triplett <josh@freedesktop.org>
  *
  * See also:  Documentation/RCU/torture.txt
  */
@@ -50,7 +50,7 @@
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and "
-              "Josh Triplett <josh@freedesktop.org>");
+	      "Josh Triplett <josh@freedesktop.org>");
 
 static int nreaders = -1;	/* # reader threads, defaults to 2*ncpus */
 static int nfakewriters = 4;	/* # fake writer threads */
@@ -110,8 +110,8 @@ struct rcu_torture {
 };
 
 static LIST_HEAD(rcu_torture_freelist);
-static struct rcu_torture *rcu_torture_current = NULL;
-static long rcu_torture_current_version = 0;
+static struct rcu_torture *rcu_torture_current;
+static long rcu_torture_current_version;
 static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN];
 static DEFINE_SPINLOCK(rcu_torture_lock);
 static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) =
@@ -124,11 +124,11 @@ static atomic_t n_rcu_torture_alloc_fail;
 static atomic_t n_rcu_torture_free;
 static atomic_t n_rcu_torture_mberror;
 static atomic_t n_rcu_torture_error;
-static long n_rcu_torture_timers = 0;
+static long n_rcu_torture_timers;
 static struct list_head rcu_torture_removed;
 static cpumask_var_t shuffle_tmp_mask;
 
-static int stutter_pause_test = 0;
+static int stutter_pause_test;
 
 #if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE)
 #define RCUTORTURE_RUNNABLE_INIT 1
@@ -257,17 +257,18 @@ struct rcu_torture_ops {
 	void (*init)(void);
 	void (*cleanup)(void);
 	int (*readlock)(void);
-	void (*readdelay)(struct rcu_random_state *rrsp);
+	void (*read_delay)(struct rcu_random_state *rrsp);
 	void (*readunlock)(int idx);
 	int (*completed)(void);
-	void (*deferredfree)(struct rcu_torture *p);
+	void (*deferred_free)(struct rcu_torture *p);
 	void (*sync)(void);
 	void (*cb_barrier)(void);
 	int (*stats)(char *page);
-	int irqcapable;
+	int irq_capable;
 	char *name;
 };
-static struct rcu_torture_ops *cur_ops = NULL;
+
+static struct rcu_torture_ops *cur_ops;
 
 /*
  * Definitions for rcu torture testing.
@@ -281,14 +282,17 @@ static int rcu_torture_read_lock(void) __acquires(RCU)
 
 static void rcu_read_delay(struct rcu_random_state *rrsp)
 {
-	long delay;
-	const long longdelay = 200;
+	const unsigned long shortdelay_us = 200;
+	const unsigned long longdelay_ms = 50;
 
-	/* We want there to be long-running readers, but not all the time. */
+	/* We want a short delay sometimes to make a reader delay the grace
+	 * period, and we want a long delay occasionally to trigger
+	 * force_quiescent_state. */
 
-	delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay);
-	if (!delay)
-		udelay(longdelay);
+	if (!(rcu_random(rrsp) % (nrealreaders * 2000 * longdelay_ms)))
+		mdelay(longdelay_ms);
+	if (!(rcu_random(rrsp) % (nrealreaders * 2 * shortdelay_us)))
+		udelay(shortdelay_us);
 }
 
 static void rcu_torture_read_unlock(int idx) __releases(RCU)
@@ -320,7 +324,7 @@ rcu_torture_cb(struct rcu_head *p)
 		rp->rtort_mbtest = 0;
 		rcu_torture_free(rp);
 	} else
-		cur_ops->deferredfree(rp);
+		cur_ops->deferred_free(rp);
 }
 
 static void rcu_torture_deferred_free(struct rcu_torture *p)
@@ -329,18 +333,18 @@ static void rcu_torture_deferred_free(struct rcu_torture *p)
 }
 
 static struct rcu_torture_ops rcu_ops = {
-	.init = NULL,
-	.cleanup = NULL,
-	.readlock = rcu_torture_read_lock,
-	.readdelay = rcu_read_delay,
-	.readunlock = rcu_torture_read_unlock,
-	.completed = rcu_torture_completed,
-	.deferredfree = rcu_torture_deferred_free,
-	.sync = synchronize_rcu,
-	.cb_barrier = rcu_barrier,
-	.stats = NULL,
-	.irqcapable = 1,
-	.name = "rcu"
+	.init		= NULL,
+	.cleanup	= NULL,
+	.readlock	= rcu_torture_read_lock,
+	.read_delay	= rcu_read_delay,
+	.readunlock	= rcu_torture_read_unlock,
+	.completed	= rcu_torture_completed,
+	.deferred_free	= rcu_torture_deferred_free,
+	.sync		= synchronize_rcu,
+	.cb_barrier	= rcu_barrier,
+	.stats		= NULL,
+	.irq_capable	= 1,
+	.name		= "rcu"
 };
 
 static void rcu_sync_torture_deferred_free(struct rcu_torture *p)
@@ -370,18 +374,18 @@ static void rcu_sync_torture_init(void)
 }
 
 static struct rcu_torture_ops rcu_sync_ops = {
-	.init = rcu_sync_torture_init,
-	.cleanup = NULL,
-	.readlock = rcu_torture_read_lock,
-	.readdelay = rcu_read_delay,
-	.readunlock = rcu_torture_read_unlock,
-	.completed = rcu_torture_completed,
-	.deferredfree = rcu_sync_torture_deferred_free,
-	.sync = synchronize_rcu,
-	.cb_barrier = NULL,
-	.stats = NULL,
-	.irqcapable = 1,
-	.name = "rcu_sync"
+	.init		= rcu_sync_torture_init,
+	.cleanup	= NULL,
+	.readlock	= rcu_torture_read_lock,
+	.read_delay	= rcu_read_delay,
+	.readunlock	= rcu_torture_read_unlock,
+	.completed	= rcu_torture_completed,
+	.deferred_free	= rcu_sync_torture_deferred_free,
+	.sync		= synchronize_rcu,
+	.cb_barrier	= NULL,
+	.stats		= NULL,
+	.irq_capable	= 1,
+	.name		= "rcu_sync"
 };
 
 /*
@@ -432,33 +436,33 @@ static void rcu_bh_torture_synchronize(void)
 }
 
 static struct rcu_torture_ops rcu_bh_ops = {
-	.init = NULL,
-	.cleanup = NULL,
-	.readlock = rcu_bh_torture_read_lock,
-	.readdelay = rcu_read_delay,  /* just reuse rcu's version. */
-	.readunlock = rcu_bh_torture_read_unlock,
-	.completed = rcu_bh_torture_completed,
-	.deferredfree = rcu_bh_torture_deferred_free,
-	.sync = rcu_bh_torture_synchronize,
-	.cb_barrier = rcu_barrier_bh,
-	.stats = NULL,
-	.irqcapable = 1,
-	.name = "rcu_bh"
+	.init		= NULL,
+	.cleanup	= NULL,
+	.readlock	= rcu_bh_torture_read_lock,
+	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
+	.readunlock	= rcu_bh_torture_read_unlock,
+	.completed	= rcu_bh_torture_completed,
+	.deferred_free	= rcu_bh_torture_deferred_free,
+	.sync		= rcu_bh_torture_synchronize,
+	.cb_barrier	= rcu_barrier_bh,
+	.stats		= NULL,
+	.irq_capable	= 1,
+	.name		= "rcu_bh"
 };
 
 static struct rcu_torture_ops rcu_bh_sync_ops = {
-	.init = rcu_sync_torture_init,
-	.cleanup = NULL,
-	.readlock = rcu_bh_torture_read_lock,
-	.readdelay = rcu_read_delay,  /* just reuse rcu's version. */
-	.readunlock = rcu_bh_torture_read_unlock,
-	.completed = rcu_bh_torture_completed,
-	.deferredfree = rcu_sync_torture_deferred_free,
-	.sync = rcu_bh_torture_synchronize,
-	.cb_barrier = NULL,
-	.stats = NULL,
-	.irqcapable = 1,
-	.name = "rcu_bh_sync"
+	.init		= rcu_sync_torture_init,
+	.cleanup	= NULL,
+	.readlock	= rcu_bh_torture_read_lock,
+	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
+	.readunlock	= rcu_bh_torture_read_unlock,
+	.completed	= rcu_bh_torture_completed,
+	.deferred_free	= rcu_sync_torture_deferred_free,
+	.sync		= rcu_bh_torture_synchronize,
+	.cb_barrier	= NULL,
+	.stats		= NULL,
+	.irq_capable	= 1,
+	.name		= "rcu_bh_sync"
 };
 
 /*
@@ -530,17 +534,17 @@ static int srcu_torture_stats(char *page)
 }
 
 static struct rcu_torture_ops srcu_ops = {
-	.init = srcu_torture_init,
-	.cleanup = srcu_torture_cleanup,
-	.readlock = srcu_torture_read_lock,
-	.readdelay = srcu_read_delay,
-	.readunlock = srcu_torture_read_unlock,
-	.completed = srcu_torture_completed,
-	.deferredfree = rcu_sync_torture_deferred_free,
-	.sync = srcu_torture_synchronize,
-	.cb_barrier = NULL,
-	.stats = srcu_torture_stats,
-	.name = "srcu"
+	.init		= srcu_torture_init,
+	.cleanup	= srcu_torture_cleanup,
+	.readlock	= srcu_torture_read_lock,
+	.read_delay	= srcu_read_delay,
+	.readunlock	= srcu_torture_read_unlock,
+	.completed	= srcu_torture_completed,
+	.deferred_free	= rcu_sync_torture_deferred_free,
+	.sync		= srcu_torture_synchronize,
+	.cb_barrier	= NULL,
+	.stats		= srcu_torture_stats,
+	.name		= "srcu"
 };
 
 /*
@@ -574,32 +578,49 @@ static void sched_torture_synchronize(void)
 }
 
 static struct rcu_torture_ops sched_ops = {
-	.init = rcu_sync_torture_init,
-	.cleanup = NULL,
-	.readlock = sched_torture_read_lock,
-	.readdelay = rcu_read_delay,  /* just reuse rcu's version. */
-	.readunlock = sched_torture_read_unlock,
-	.completed = sched_torture_completed,
-	.deferredfree = rcu_sched_torture_deferred_free,
-	.sync = sched_torture_synchronize,
-	.cb_barrier = rcu_barrier_sched,
-	.stats = NULL,
-	.irqcapable = 1,
-	.name = "sched"
+	.init		= rcu_sync_torture_init,
+	.cleanup	= NULL,
+	.readlock	= sched_torture_read_lock,
+	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
+	.readunlock	= sched_torture_read_unlock,
+	.completed	= sched_torture_completed,
+	.deferred_free	= rcu_sched_torture_deferred_free,
+	.sync		= sched_torture_synchronize,
+	.cb_barrier	= rcu_barrier_sched,
+	.stats		= NULL,
+	.irq_capable	= 1,
+	.name		= "sched"
 };
 
 static struct rcu_torture_ops sched_ops_sync = {
-	.init = rcu_sync_torture_init,
-	.cleanup = NULL,
-	.readlock = sched_torture_read_lock,
-	.readdelay = rcu_read_delay,  /* just reuse rcu's version. */
-	.readunlock = sched_torture_read_unlock,
-	.completed = sched_torture_completed,
-	.deferredfree = rcu_sync_torture_deferred_free,
-	.sync = sched_torture_synchronize,
-	.cb_barrier = NULL,
-	.stats = NULL,
-	.name = "sched_sync"
+	.init		= rcu_sync_torture_init,
+	.cleanup	= NULL,
+	.readlock	= sched_torture_read_lock,
+	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
+	.readunlock	= sched_torture_read_unlock,
+	.completed	= sched_torture_completed,
+	.deferred_free	= rcu_sync_torture_deferred_free,
+	.sync		= sched_torture_synchronize,
+	.cb_barrier	= NULL,
+	.stats		= NULL,
+	.name		= "sched_sync"
+};
+
+extern int rcu_expedited_torture_stats(char *page);
+
+static struct rcu_torture_ops sched_expedited_ops = {
+	.init		= rcu_sync_torture_init,
+	.cleanup	= NULL,
+	.readlock	= sched_torture_read_lock,
+	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
+	.readunlock	= sched_torture_read_unlock,
+	.completed	= sched_torture_completed,
+	.deferred_free	= rcu_sync_torture_deferred_free,
+	.sync		= synchronize_sched_expedited,
+	.cb_barrier	= NULL,
+	.stats		= rcu_expedited_torture_stats,
+	.irq_capable	= 1,
+	.name		= "sched_expedited"
 };
 
 /*
@@ -621,7 +642,8 @@ rcu_torture_writer(void *arg)
 
 	do {
 		schedule_timeout_uninterruptible(1);
-		if ((rp = rcu_torture_alloc()) == NULL)
+		rp = rcu_torture_alloc();
+		if (rp == NULL)
 			continue;
 		rp->rtort_pipe_count = 0;
 		udelay(rcu_random(&rand) & 0x3ff);
@@ -635,7 +657,7 @@ rcu_torture_writer(void *arg)
 				i = RCU_TORTURE_PIPE_LEN;
 			atomic_inc(&rcu_torture_wcount[i]);
 			old_rp->rtort_pipe_count++;
-			cur_ops->deferredfree(old_rp);
+			cur_ops->deferred_free(old_rp);
 		}
 		rcu_torture_current_version++;
 		oldbatch = cur_ops->completed();
@@ -700,7 +722,7 @@ static void rcu_torture_timer(unsigned long unused)
 	if (p->rtort_mbtest == 0)
 		atomic_inc(&n_rcu_torture_mberror);
 	spin_lock(&rand_lock);
-	cur_ops->readdelay(&rand);
+	cur_ops->read_delay(&rand);
 	n_rcu_torture_timers++;
 	spin_unlock(&rand_lock);
 	preempt_disable();
@@ -738,11 +760,11 @@ rcu_torture_reader(void *arg)
 
 	VERBOSE_PRINTK_STRING("rcu_torture_reader task started");
 	set_user_nice(current, 19);
-	if (irqreader && cur_ops->irqcapable)
+	if (irqreader && cur_ops->irq_capable)
 		setup_timer_on_stack(&t, rcu_torture_timer, 0);
 
 	do {
-		if (irqreader && cur_ops->irqcapable) {
+		if (irqreader && cur_ops->irq_capable) {
 			if (!timer_pending(&t))
 				mod_timer(&t, 1);
 		}
@@ -757,7 +779,7 @@ rcu_torture_reader(void *arg)
 		}
 		if (p->rtort_mbtest == 0)
 			atomic_inc(&n_rcu_torture_mberror);
-		cur_ops->readdelay(&rand);
+		cur_ops->read_delay(&rand);
 		preempt_disable();
 		pipe_count = p->rtort_pipe_count;
 		if (pipe_count > RCU_TORTURE_PIPE_LEN) {
@@ -778,7 +800,7 @@ rcu_torture_reader(void *arg)
 	} while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
 	VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping");
 	rcutorture_shutdown_absorb("rcu_torture_reader");
-	if (irqreader && cur_ops->irqcapable)
+	if (irqreader && cur_ops->irq_capable)
 		del_timer_sync(&t);
 	while (!kthread_should_stop())
 		schedule_timeout_uninterruptible(1);
@@ -1078,6 +1100,7 @@ rcu_torture_init(void)
 	int firsterr = 0;
 	static struct rcu_torture_ops *torture_ops[] =
 		{ &rcu_ops, &rcu_sync_ops, &rcu_bh_ops, &rcu_bh_sync_ops,
+		  &sched_expedited_ops,
 		  &srcu_ops, &sched_ops, &sched_ops_sync, };
 
 	mutex_lock(&fullstop_mutex);
@@ -1092,7 +1115,7 @@ rcu_torture_init(void)
 		printk(KERN_ALERT "rcutorture: invalid torture type: \"%s\"\n",
 		       torture_type);
 		mutex_unlock(&fullstop_mutex);
-		return (-EINVAL);
+		return -EINVAL;
 	}
 	if (cur_ops->init)
 		cur_ops->init(); /* no "goto unwind" prior to this point!!! */
@@ -1143,7 +1166,7 @@ rcu_torture_init(void)
 		goto unwind;
 	}
 	fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]),
-	                           GFP_KERNEL);
+				   GFP_KERNEL);
 	if (fakewriter_tasks == NULL) {
 		VERBOSE_PRINTK_ERRSTRING("out of memory");
 		firsterr = -ENOMEM;
@@ -1152,7 +1175,7 @@ rcu_torture_init(void)
 	for (i = 0; i < nfakewriters; i++) {
 		VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task");
 		fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL,
-		                                  "rcu_torture_fakewriter");
+						  "rcu_torture_fakewriter");
 		if (IS_ERR(fakewriter_tasks[i])) {
 			firsterr = PTR_ERR(fakewriter_tasks[i]);
 			VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter");
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 7717b95..52b06f6 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -25,7 +25,7 @@
  * and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen.
  *
  * For detailed explanation of Read-Copy Update mechanism see -
- * 	Documentation/RCU
+ *	Documentation/RCU
  */
 #include <linux/types.h>
 #include <linux/kernel.h>
@@ -35,6 +35,7 @@
 #include <linux/rcupdate.h>
 #include <linux/interrupt.h>
 #include <linux/sched.h>
+#include <linux/nmi.h>
 #include <asm/atomic.h>
 #include <linux/bitops.h>
 #include <linux/module.h>
@@ -46,6 +47,8 @@
 #include <linux/mutex.h>
 #include <linux/time.h>
 
+#include "rcutree.h"
+
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 static struct lock_class_key rcu_lock_key;
 struct lockdep_map rcu_lock_map =
@@ -72,30 +75,55 @@ EXPORT_SYMBOL_GPL(rcu_lock_map);
 	.n_force_qs_ngp = 0, \
 }
 
-struct rcu_state rcu_state = RCU_STATE_INITIALIZER(rcu_state);
-DEFINE_PER_CPU(struct rcu_data, rcu_data);
+struct rcu_state rcu_sched_state = RCU_STATE_INITIALIZER(rcu_sched_state);
+DEFINE_PER_CPU(struct rcu_data, rcu_sched_data);
 
 struct rcu_state rcu_bh_state = RCU_STATE_INITIALIZER(rcu_bh_state);
 DEFINE_PER_CPU(struct rcu_data, rcu_bh_data);
 
+extern long rcu_batches_completed_sched(void);
+static struct rcu_node *rcu_get_root(struct rcu_state *rsp);
+static void cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp,
+			  struct rcu_node *rnp, unsigned long flags);
+static void cpu_quiet_msk_finish(struct rcu_state *rsp, unsigned long flags);
+#ifdef CONFIG_HOTPLUG_CPU
+static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp);
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+static void __rcu_process_callbacks(struct rcu_state *rsp,
+				    struct rcu_data *rdp);
+static void __call_rcu(struct rcu_head *head,
+		       void (*func)(struct rcu_head *rcu),
+		       struct rcu_state *rsp);
+static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp);
+static void __cpuinit rcu_init_percpu_data(int cpu, struct rcu_state *rsp,
+					   int preemptable);
+
+#include "rcutree_plugin.h"
+
 /*
- * Increment the quiescent state counter.
- * The counter is a bit degenerated: We do not need to know
+ * Note a quiescent state.  Because we do not need to know
  * how many quiescent states passed, just if there was at least
- * one since the start of the grace period. Thus just a flag.
+ * one since the start of the grace period, this just sets a flag.
  */
-void rcu_qsctr_inc(int cpu)
+void rcu_sched_qs(int cpu)
 {
-	struct rcu_data *rdp = &per_cpu(rcu_data, cpu);
-	rdp->passed_quiesc = 1;
+	struct rcu_data *rdp;
+
+	rdp = &per_cpu(rcu_sched_data, cpu);
 	rdp->passed_quiesc_completed = rdp->completed;
+	barrier();
+	rdp->passed_quiesc = 1;
+	rcu_preempt_note_context_switch(cpu);
 }
 
-void rcu_bh_qsctr_inc(int cpu)
+void rcu_bh_qs(int cpu)
 {
-	struct rcu_data *rdp = &per_cpu(rcu_bh_data, cpu);
-	rdp->passed_quiesc = 1;
+	struct rcu_data *rdp;
+
+	rdp = &per_cpu(rcu_bh_data, cpu);
 	rdp->passed_quiesc_completed = rdp->completed;
+	barrier();
+	rdp->passed_quiesc = 1;
 }
 
 #ifdef CONFIG_NO_HZ
@@ -110,15 +138,16 @@ static int qhimark = 10000;	/* If this many pending, ignore blimit. */
 static int qlowmark = 100;	/* Once only this many pending, use blimit. */
 
 static void force_quiescent_state(struct rcu_state *rsp, int relaxed);
+static int rcu_pending(int cpu);
 
 /*
- * Return the number of RCU batches processed thus far for debug & stats.
+ * Return the number of RCU-sched batches processed thus far for debug & stats.
  */
-long rcu_batches_completed(void)
+long rcu_batches_completed_sched(void)
 {
-	return rcu_state.completed;
+	return rcu_sched_state.completed;
 }
-EXPORT_SYMBOL_GPL(rcu_batches_completed);
+EXPORT_SYMBOL_GPL(rcu_batches_completed_sched);
 
 /*
  * Return the number of RCU BH batches processed thus far for debug & stats.
@@ -181,6 +210,10 @@ static int rcu_implicit_offline_qs(struct rcu_data *rdp)
 		return 1;
 	}
 
+	/* If preemptable RCU, no point in sending reschedule IPI. */
+	if (rdp->preemptable)
+		return 0;
+
 	/* The CPU is online, so send it a reschedule IPI. */
 	if (rdp->cpu != smp_processor_id())
 		smp_send_reschedule(rdp->cpu);
@@ -193,7 +226,6 @@ static int rcu_implicit_offline_qs(struct rcu_data *rdp)
 #endif /* #ifdef CONFIG_SMP */
 
 #ifdef CONFIG_NO_HZ
-static DEFINE_RATELIMIT_STATE(rcu_rs, 10 * HZ, 5);
 
 /**
  * rcu_enter_nohz - inform RCU that current CPU is entering nohz
@@ -213,7 +245,7 @@ void rcu_enter_nohz(void)
 	rdtp = &__get_cpu_var(rcu_dynticks);
 	rdtp->dynticks++;
 	rdtp->dynticks_nesting--;
-	WARN_ON_RATELIMIT(rdtp->dynticks & 0x1, &rcu_rs);
+	WARN_ON_ONCE(rdtp->dynticks & 0x1);
 	local_irq_restore(flags);
 }
 
@@ -232,7 +264,7 @@ void rcu_exit_nohz(void)
 	rdtp = &__get_cpu_var(rcu_dynticks);
 	rdtp->dynticks++;
 	rdtp->dynticks_nesting++;
-	WARN_ON_RATELIMIT(!(rdtp->dynticks & 0x1), &rcu_rs);
+	WARN_ON_ONCE(!(rdtp->dynticks & 0x1));
 	local_irq_restore(flags);
 	smp_mb(); /* CPUs seeing ++ must see later RCU read-side crit sects */
 }
@@ -251,7 +283,7 @@ void rcu_nmi_enter(void)
 	if (rdtp->dynticks & 0x1)
 		return;
 	rdtp->dynticks_nmi++;
-	WARN_ON_RATELIMIT(!(rdtp->dynticks_nmi & 0x1), &rcu_rs);
+	WARN_ON_ONCE(!(rdtp->dynticks_nmi & 0x1));
 	smp_mb(); /* CPUs seeing ++ must see later RCU read-side crit sects */
 }
 
@@ -270,7 +302,7 @@ void rcu_nmi_exit(void)
 		return;
 	smp_mb(); /* CPUs seeing ++ must see prior RCU read-side crit sects */
 	rdtp->dynticks_nmi++;
-	WARN_ON_RATELIMIT(rdtp->dynticks_nmi & 0x1, &rcu_rs);
+	WARN_ON_ONCE(rdtp->dynticks_nmi & 0x1);
 }
 
 /**
@@ -286,7 +318,7 @@ void rcu_irq_enter(void)
 	if (rdtp->dynticks_nesting++)
 		return;
 	rdtp->dynticks++;
-	WARN_ON_RATELIMIT(!(rdtp->dynticks & 0x1), &rcu_rs);
+	WARN_ON_ONCE(!(rdtp->dynticks & 0x1));
 	smp_mb(); /* CPUs seeing ++ must see later RCU read-side crit sects */
 }
 
@@ -305,10 +337,10 @@ void rcu_irq_exit(void)
 		return;
 	smp_mb(); /* CPUs seeing ++ must see prior RCU read-side crit sects */
 	rdtp->dynticks++;
-	WARN_ON_RATELIMIT(rdtp->dynticks & 0x1, &rcu_rs);
+	WARN_ON_ONCE(rdtp->dynticks & 0x1);
 
 	/* If the interrupt queued a callback, get out of dyntick mode. */
-	if (__get_cpu_var(rcu_data).nxtlist ||
+	if (__get_cpu_var(rcu_sched_data).nxtlist ||
 	    __get_cpu_var(rcu_bh_data).nxtlist)
 		set_need_resched();
 }
@@ -461,6 +493,7 @@ static void print_other_cpu_stall(struct rcu_state *rsp)
 
 	printk(KERN_ERR "INFO: RCU detected CPU stalls:");
 	for (; rnp_cur < rnp_end; rnp_cur++) {
+		rcu_print_task_stall(rnp);
 		if (rnp_cur->qsmask == 0)
 			continue;
 		for (cpu = 0; cpu <= rnp_cur->grphi - rnp_cur->grplo; cpu++)
@@ -469,6 +502,8 @@ static void print_other_cpu_stall(struct rcu_state *rsp)
 	}
 	printk(" (detected by %d, t=%ld jiffies)\n",
 	       smp_processor_id(), (long)(jiffies - rsp->gp_start));
+	trigger_all_cpu_backtrace();
+
 	force_quiescent_state(rsp, 0);  /* Kick them all. */
 }
 
@@ -479,12 +514,14 @@ static void print_cpu_stall(struct rcu_state *rsp)
 
 	printk(KERN_ERR "INFO: RCU detected CPU %d stall (t=%lu jiffies)\n",
 			smp_processor_id(), jiffies - rsp->gp_start);
-	dump_stack();
+	trigger_all_cpu_backtrace();
+
 	spin_lock_irqsave(&rnp->lock, flags);
 	if ((long)(jiffies - rsp->jiffies_stall) >= 0)
 		rsp->jiffies_stall =
 			jiffies + RCU_SECONDS_TILL_STALL_RECHECK;
 	spin_unlock_irqrestore(&rnp->lock, flags);
+
 	set_need_resched();  /* kick ourselves to get things going. */
 }
 
@@ -564,8 +601,6 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
 {
 	struct rcu_data *rdp = rsp->rda[smp_processor_id()];
 	struct rcu_node *rnp = rcu_get_root(rsp);
-	struct rcu_node *rnp_cur;
-	struct rcu_node *rnp_end;
 
 	if (!cpu_needs_another_gp(rsp, rdp)) {
 		spin_unlock_irqrestore(&rnp->lock, flags);
@@ -574,6 +609,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
 
 	/* Advance to a new grace period and initialize state. */
 	rsp->gpnum++;
+	WARN_ON_ONCE(rsp->signaled == RCU_GP_INIT);
 	rsp->signaled = RCU_GP_INIT; /* Hold off force_quiescent_state. */
 	rsp->jiffies_force_qs = jiffies + RCU_JIFFIES_TILL_FORCE_QS;
 	record_gp_stall_check_time(rsp);
@@ -590,7 +626,9 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
 
 	/* Special-case the common single-level case. */
 	if (NUM_RCU_NODES == 1) {
+		rcu_preempt_check_blocked_tasks(rnp);
 		rnp->qsmask = rnp->qsmaskinit;
+		rnp->gpnum = rsp->gpnum;
 		rsp->signaled = RCU_SIGNAL_INIT; /* force_quiescent_state OK. */
 		spin_unlock_irqrestore(&rnp->lock, flags);
 		return;
@@ -603,42 +641,28 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
 	spin_lock(&rsp->onofflock);  /* irqs already disabled. */
 
 	/*
-	 * Set the quiescent-state-needed bits in all the non-leaf RCU
-	 * nodes for all currently online CPUs.  This operation relies
-	 * on the layout of the hierarchy within the rsp->node[] array.
-	 * Note that other CPUs will access only the leaves of the
-	 * hierarchy, which still indicate that no grace period is in
-	 * progress.  In addition, we have excluded CPU-hotplug operations.
-	 *
-	 * We therefore do not need to hold any locks.  Any required
-	 * memory barriers will be supplied by the locks guarding the
-	 * leaf rcu_nodes in the hierarchy.
-	 */
-
-	rnp_end = rsp->level[NUM_RCU_LVLS - 1];
-	for (rnp_cur = &rsp->node[0]; rnp_cur < rnp_end; rnp_cur++)
-		rnp_cur->qsmask = rnp_cur->qsmaskinit;
-
-	/*
-	 * Now set up the leaf nodes.  Here we must be careful.  First,
-	 * we need to hold the lock in order to exclude other CPUs, which
-	 * might be contending for the leaf nodes' locks.  Second, as
-	 * soon as we initialize a given leaf node, its CPUs might run
-	 * up the rest of the hierarchy.  We must therefore acquire locks
-	 * for each node that we touch during this stage.  (But we still
-	 * are excluding CPU-hotplug operations.)
+	 * Set the quiescent-state-needed bits in all the rcu_node
+	 * structures for all currently online CPUs in breadth-first
+	 * order, starting from the root rcu_node structure.  This
+	 * operation relies on the layout of the hierarchy within the
+	 * rsp->node[] array.  Note that other CPUs will access only
+	 * the leaves of the hierarchy, which still indicate that no
+	 * grace period is in progress, at least until the corresponding
+	 * leaf node has been initialized.  In addition, we have excluded
+	 * CPU-hotplug operations.
 	 *
 	 * Note that the grace period cannot complete until we finish
 	 * the initialization process, as there will be at least one
 	 * qsmask bit set in the root node until that time, namely the
-	 * one corresponding to this CPU.
+	 * one corresponding to this CPU, due to the fact that we have
+	 * irqs disabled.
 	 */
-	rnp_end = &rsp->node[NUM_RCU_NODES];
-	rnp_cur = rsp->level[NUM_RCU_LVLS - 1];
-	for (; rnp_cur < rnp_end; rnp_cur++) {
-		spin_lock(&rnp_cur->lock);	/* irqs already disabled. */
-		rnp_cur->qsmask = rnp_cur->qsmaskinit;
-		spin_unlock(&rnp_cur->lock);	/* irqs already disabled. */
+	for (rnp = &rsp->node[0]; rnp < &rsp->node[NUM_RCU_NODES]; rnp++) {
+		spin_lock(&rnp->lock);	/* irqs already disabled. */
+		rcu_preempt_check_blocked_tasks(rnp);
+		rnp->qsmask = rnp->qsmaskinit;
+		rnp->gpnum = rsp->gpnum;
+		spin_unlock(&rnp->lock);	/* irqs already disabled. */
 	}
 
 	rsp->signaled = RCU_SIGNAL_INIT; /* force_quiescent_state now OK. */
@@ -674,6 +698,20 @@ rcu_process_gp_end(struct rcu_state *rsp, struct rcu_data *rdp)
 }
 
 /*
+ * Clean up after the prior grace period and let rcu_start_gp() start up
+ * the next grace period if one is needed.  Note that the caller must
+ * hold rnp->lock, as required by rcu_start_gp(), which will release it.
+ */
+static void cpu_quiet_msk_finish(struct rcu_state *rsp, unsigned long flags)
+	__releases(rnp->lock)
+{
+	WARN_ON_ONCE(rsp->completed == rsp->gpnum);
+	rsp->completed = rsp->gpnum;
+	rcu_process_gp_end(rsp, rsp->rda[smp_processor_id()]);
+	rcu_start_gp(rsp, flags);  /* releases root node's rnp->lock. */
+}
+
+/*
  * Similar to cpu_quiet(), for which it is a helper function.  Allows
  * a group of CPUs to be quieted at one go, though all the CPUs in the
  * group must be represented by the same leaf rcu_node structure.
@@ -685,6 +723,8 @@ cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp, struct rcu_node *rnp,
 	      unsigned long flags)
 	__releases(rnp->lock)
 {
+	struct rcu_node *rnp_c;
+
 	/* Walk up the rcu_node hierarchy. */
 	for (;;) {
 		if (!(rnp->qsmask & mask)) {
@@ -694,7 +734,7 @@ cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp, struct rcu_node *rnp,
 			return;
 		}
 		rnp->qsmask &= ~mask;
-		if (rnp->qsmask != 0) {
+		if (rnp->qsmask != 0 || rcu_preempted_readers(rnp)) {
 
 			/* Other bits still set at this level, so done. */
 			spin_unlock_irqrestore(&rnp->lock, flags);
@@ -708,28 +748,26 @@ cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp, struct rcu_node *rnp,
 			break;
 		}
 		spin_unlock_irqrestore(&rnp->lock, flags);
+		rnp_c = rnp;
 		rnp = rnp->parent;
 		spin_lock_irqsave(&rnp->lock, flags);
+		WARN_ON_ONCE(rnp_c->qsmask);
 	}
 
 	/*
 	 * Get here if we are the last CPU to pass through a quiescent
-	 * state for this grace period.  Clean up and let rcu_start_gp()
-	 * start up the next grace period if one is needed.  Note that
-	 * we still hold rnp->lock, as required by rcu_start_gp(), which
-	 * will release it.
+	 * state for this grace period.  Invoke cpu_quiet_msk_finish()
+	 * to clean up and start the next grace period if one is needed.
 	 */
-	rsp->completed = rsp->gpnum;
-	rcu_process_gp_end(rsp, rsp->rda[smp_processor_id()]);
-	rcu_start_gp(rsp, flags);  /* releases rnp->lock. */
+	cpu_quiet_msk_finish(rsp, flags); /* releases rnp->lock. */
 }
 
 /*
  * Record a quiescent state for the specified CPU, which must either be
- * the current CPU or an offline CPU.  The lastcomp argument is used to
- * make sure we are still in the grace period of interest.  We don't want
- * to end the current grace period based on quiescent states detected in
- * an earlier grace period!
+ * the current CPU.  The lastcomp argument is used to make sure we are
+ * still in the grace period of interest.  We don't want to end the current
+ * grace period based on quiescent states detected in an earlier grace
+ * period!
  */
 static void
 cpu_quiet(int cpu, struct rcu_state *rsp, struct rcu_data *rdp, long lastcomp)
@@ -764,7 +802,6 @@ cpu_quiet(int cpu, struct rcu_state *rsp, struct rcu_data *rdp, long lastcomp)
 		 * This GP can't end until cpu checks in, so all of our
 		 * callbacks can be processed during the next GP.
 		 */
-		rdp = rsp->rda[smp_processor_id()];
 		rdp->nxttail[RCU_NEXT_READY_TAIL] = rdp->nxttail[RCU_NEXT_TAIL];
 
 		cpu_quiet_msk(mask, rsp, rnp, flags); /* releases rnp->lock */
@@ -822,30 +859,28 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
 	spin_lock_irqsave(&rsp->onofflock, flags);
 
 	/* Remove the outgoing CPU from the masks in the rcu_node hierarchy. */
-	rnp = rdp->mynode;
+	rnp = rdp->mynode;	/* this is the outgoing CPU's rnp. */
 	mask = rdp->grpmask;	/* rnp->grplo is constant. */
 	do {
 		spin_lock(&rnp->lock);		/* irqs already disabled. */
 		rnp->qsmaskinit &= ~mask;
 		if (rnp->qsmaskinit != 0) {
-			spin_unlock(&rnp->lock); /* irqs already disabled. */
+			spin_unlock(&rnp->lock); /* irqs remain disabled. */
 			break;
 		}
+		rcu_preempt_offline_tasks(rsp, rnp, rdp);
 		mask = rnp->grpmask;
-		spin_unlock(&rnp->lock);	/* irqs already disabled. */
+		spin_unlock(&rnp->lock);	/* irqs remain disabled. */
 		rnp = rnp->parent;
 	} while (rnp != NULL);
 	lastcomp = rsp->completed;
 
 	spin_unlock(&rsp->onofflock);		/* irqs remain disabled. */
 
-	/* Being offline is a quiescent state, so go record it. */
-	cpu_quiet(cpu, rsp, rdp, lastcomp);
-
 	/*
 	 * Move callbacks from the outgoing CPU to the running CPU.
 	 * Note that the outgoing CPU is now quiscent, so it is now
-	 * (uncharacteristically) safe to access it rcu_data structure.
+	 * (uncharacteristically) safe to access its rcu_data structure.
 	 * Note also that we must carefully retain the order of the
 	 * outgoing CPU's callbacks in order for rcu_barrier() to work
 	 * correctly.  Finally, note that we start all the callbacks
@@ -876,8 +911,9 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
  */
 static void rcu_offline_cpu(int cpu)
 {
-	__rcu_offline_cpu(cpu, &rcu_state);
+	__rcu_offline_cpu(cpu, &rcu_sched_state);
 	__rcu_offline_cpu(cpu, &rcu_bh_state);
+	rcu_preempt_offline_cpu(cpu);
 }
 
 #else /* #ifdef CONFIG_HOTPLUG_CPU */
@@ -963,6 +999,8 @@ static void rcu_do_batch(struct rcu_data *rdp)
  */
 void rcu_check_callbacks(int cpu, int user)
 {
+	if (!rcu_pending(cpu))
+		return; /* if nothing for RCU to do. */
 	if (user ||
 	    (idle_cpu(cpu) && rcu_scheduler_active &&
 	     !in_softirq() && hardirq_count() <= (1 << HARDIRQ_SHIFT))) {
@@ -971,17 +1009,16 @@ void rcu_check_callbacks(int cpu, int user)
 		 * Get here if this CPU took its interrupt from user
 		 * mode or from the idle loop, and if this is not a
 		 * nested interrupt.  In this case, the CPU is in
-		 * a quiescent state, so count it.
+		 * a quiescent state, so note it.
 		 *
 		 * No memory barrier is required here because both
-		 * rcu_qsctr_inc() and rcu_bh_qsctr_inc() reference
-		 * only CPU-local variables that other CPUs neither
-		 * access nor modify, at least not while the corresponding
-		 * CPU is online.
+		 * rcu_sched_qs() and rcu_bh_qs() reference only CPU-local
+		 * variables that other CPUs neither access nor modify,
+		 * at least not while the corresponding CPU is online.
 		 */
 
-		rcu_qsctr_inc(cpu);
-		rcu_bh_qsctr_inc(cpu);
+		rcu_sched_qs(cpu);
+		rcu_bh_qs(cpu);
 
 	} else if (!in_softirq()) {
 
@@ -989,11 +1026,12 @@ void rcu_check_callbacks(int cpu, int user)
 		 * Get here if this CPU did not take its interrupt from
 		 * softirq, in other words, if it is not interrupting
 		 * a rcu_bh read-side critical section.  This is an _bh
-		 * critical section, so count it.
+		 * critical section, so note it.
 		 */
 
-		rcu_bh_qsctr_inc(cpu);
+		rcu_bh_qs(cpu);
 	}
+	rcu_preempt_check_callbacks(cpu);
 	raise_softirq(RCU_SOFTIRQ);
 }
 
@@ -1132,6 +1170,8 @@ __rcu_process_callbacks(struct rcu_state *rsp, struct rcu_data *rdp)
 {
 	unsigned long flags;
 
+	WARN_ON_ONCE(rdp->beenonline == 0);
+
 	/*
 	 * If an RCU GP has gone long enough, go check for dyntick
 	 * idle CPUs and, if needed, send resched IPIs.
@@ -1170,8 +1210,10 @@ static void rcu_process_callbacks(struct softirq_action *unused)
 	 */
 	smp_mb(); /* See above block comment. */
 
-	__rcu_process_callbacks(&rcu_state, &__get_cpu_var(rcu_data));
+	__rcu_process_callbacks(&rcu_sched_state,
+				&__get_cpu_var(rcu_sched_data));
 	__rcu_process_callbacks(&rcu_bh_state, &__get_cpu_var(rcu_bh_data));
+	rcu_preempt_process_callbacks();
 
 	/*
 	 * Memory references from any later RCU read-side critical sections
@@ -1227,13 +1269,13 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
 }
 
 /*
- * Queue an RCU callback for invocation after a grace period.
+ * Queue an RCU-sched callback for invocation after a grace period.
  */
-void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+void call_rcu_sched(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
 {
-	__call_rcu(head, func, &rcu_state);
+	__call_rcu(head, func, &rcu_sched_state);
 }
-EXPORT_SYMBOL_GPL(call_rcu);
+EXPORT_SYMBOL_GPL(call_rcu_sched);
 
 /*
  * Queue an RCU for invocation after a quicker grace period.
@@ -1305,10 +1347,11 @@ static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp)
  * by the current CPU, returning 1 if so.  This function is part of the
  * RCU implementation; it is -not- an exported member of the RCU API.
  */
-int rcu_pending(int cpu)
+static int rcu_pending(int cpu)
 {
-	return __rcu_pending(&rcu_state, &per_cpu(rcu_data, cpu)) ||
-	       __rcu_pending(&rcu_bh_state, &per_cpu(rcu_bh_data, cpu));
+	return __rcu_pending(&rcu_sched_state, &per_cpu(rcu_sched_data, cpu)) ||
+	       __rcu_pending(&rcu_bh_state, &per_cpu(rcu_bh_data, cpu)) ||
+	       rcu_preempt_pending(cpu);
 }
 
 /*
@@ -1320,27 +1363,46 @@ int rcu_pending(int cpu)
 int rcu_needs_cpu(int cpu)
 {
 	/* RCU callbacks either ready or pending? */
-	return per_cpu(rcu_data, cpu).nxtlist ||
-	       per_cpu(rcu_bh_data, cpu).nxtlist;
+	return per_cpu(rcu_sched_data, cpu).nxtlist ||
+	       per_cpu(rcu_bh_data, cpu).nxtlist ||
+	       rcu_preempt_needs_cpu(cpu);
 }
 
 /*
- * Initialize a CPU's per-CPU RCU data.  We take this "scorched earth"
- * approach so that we don't have to worry about how long the CPU has
- * been gone, or whether it ever was online previously.  We do trust the
- * ->mynode field, as it is constant for a given struct rcu_data and
- * initialized during early boot.
- *
- * Note that only one online or offline event can be happening at a given
- * time.  Note also that we can accept some slop in the rsp->completed
- * access due to the fact that this CPU cannot possibly have any RCU
- * callbacks in flight yet.
+ * Do boot-time initialization of a CPU's per-CPU RCU data.
  */
-static void __cpuinit
-rcu_init_percpu_data(int cpu, struct rcu_state *rsp)
+static void __init
+rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp)
 {
 	unsigned long flags;
 	int i;
+	struct rcu_data *rdp = rsp->rda[cpu];
+	struct rcu_node *rnp = rcu_get_root(rsp);
+
+	/* Set up local state, ensuring consistent view of global state. */
+	spin_lock_irqsave(&rnp->lock, flags);
+	rdp->grpmask = 1UL << (cpu - rdp->mynode->grplo);
+	rdp->nxtlist = NULL;
+	for (i = 0; i < RCU_NEXT_SIZE; i++)
+		rdp->nxttail[i] = &rdp->nxtlist;
+	rdp->qlen = 0;
+#ifdef CONFIG_NO_HZ
+	rdp->dynticks = &per_cpu(rcu_dynticks, cpu);
+#endif /* #ifdef CONFIG_NO_HZ */
+	rdp->cpu = cpu;
+	spin_unlock_irqrestore(&rnp->lock, flags);
+}
+
+/*
+ * Initialize a CPU's per-CPU RCU data.  Note that only one online or
+ * offline event can be happening at a given time.  Note also that we
+ * can accept some slop in the rsp->completed access due to the fact
+ * that this CPU cannot possibly have any RCU callbacks in flight yet.
+ */
+static void __cpuinit
+rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptable)
+{
+	unsigned long flags;
 	long lastcomp;
 	unsigned long mask;
 	struct rcu_data *rdp = rsp->rda[cpu];
@@ -1354,17 +1416,9 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp)
 	rdp->passed_quiesc = 0;  /* We could be racing with new GP, */
 	rdp->qs_pending = 1;	 /*  so set up to respond to current GP. */
 	rdp->beenonline = 1;	 /* We have now been online. */
+	rdp->preemptable = preemptable;
 	rdp->passed_quiesc_completed = lastcomp - 1;
-	rdp->grpmask = 1UL << (cpu - rdp->mynode->grplo);
-	rdp->nxtlist = NULL;
-	for (i = 0; i < RCU_NEXT_SIZE; i++)
-		rdp->nxttail[i] = &rdp->nxtlist;
-	rdp->qlen = 0;
 	rdp->blimit = blimit;
-#ifdef CONFIG_NO_HZ
-	rdp->dynticks = &per_cpu(rcu_dynticks, cpu);
-#endif /* #ifdef CONFIG_NO_HZ */
-	rdp->cpu = cpu;
 	spin_unlock(&rnp->lock);		/* irqs remain disabled. */
 
 	/*
@@ -1387,34 +1441,21 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp)
 		rnp = rnp->parent;
 	} while (rnp != NULL && !(rnp->qsmaskinit & mask));
 
-	spin_unlock(&rsp->onofflock);		/* irqs remain disabled. */
-
-	/*
-	 * A new grace period might start here.  If so, we will be part of
-	 * it, and its gpnum will be greater than ours, so we will
-	 * participate.  It is also possible for the gpnum to have been
-	 * incremented before this function was called, and the bitmasks
-	 * to not be filled out until now, in which case we will also
-	 * participate due to our gpnum being behind.
-	 */
-
-	/* Since it is coming online, the CPU is in a quiescent state. */
-	cpu_quiet(cpu, rsp, rdp, lastcomp);
-	local_irq_restore(flags);
+	spin_unlock_irqrestore(&rsp->onofflock, flags);
 }
 
 static void __cpuinit rcu_online_cpu(int cpu)
 {
-	rcu_init_percpu_data(cpu, &rcu_state);
-	rcu_init_percpu_data(cpu, &rcu_bh_state);
-	open_softirq(RCU_SOFTIRQ, rcu_process_callbacks);
+	rcu_init_percpu_data(cpu, &rcu_sched_state, 0);
+	rcu_init_percpu_data(cpu, &rcu_bh_state, 0);
+	rcu_preempt_init_percpu_data(cpu);
 }
 
 /*
- * Handle CPU online/offline notifcation events.
+ * Handle CPU online/offline notification events.
  */
-static int __cpuinit rcu_cpu_notify(struct notifier_block *self,
-				unsigned long action, void *hcpu)
+int __cpuinit rcu_cpu_notify(struct notifier_block *self,
+			     unsigned long action, void *hcpu)
 {
 	long cpu = (long)hcpu;
 
@@ -1486,6 +1527,7 @@ static void __init rcu_init_one(struct rcu_state *rsp)
 		rnp = rsp->level[i];
 		for (j = 0; j < rsp->levelcnt[i]; j++, rnp++) {
 			spin_lock_init(&rnp->lock);
+			rnp->gpnum = 0;
 			rnp->qsmask = 0;
 			rnp->qsmaskinit = 0;
 			rnp->grplo = j * cpustride;
@@ -1503,16 +1545,20 @@ static void __init rcu_init_one(struct rcu_state *rsp)
 					      j / rsp->levelspread[i - 1];
 			}
 			rnp->level = i;
+			INIT_LIST_HEAD(&rnp->blocked_tasks[0]);
+			INIT_LIST_HEAD(&rnp->blocked_tasks[1]);
 		}
 	}
 }
 
 /*
- * Helper macro for __rcu_init().  To be used nowhere else!
- * Assigns leaf node pointers into each CPU's rcu_data structure.
+ * Helper macro for __rcu_init() and __rcu_init_preempt().  To be used
+ * nowhere else!  Assigns leaf node pointers into each CPU's rcu_data
+ * structure.
  */
-#define RCU_DATA_PTR_INIT(rsp, rcu_data) \
+#define RCU_INIT_FLAVOR(rsp, rcu_data) \
 do { \
+	rcu_init_one(rsp); \
 	rnp = (rsp)->level[NUM_RCU_LVLS - 1]; \
 	j = 0; \
 	for_each_possible_cpu(i) { \
@@ -1520,32 +1566,43 @@ do { \
 			j++; \
 		per_cpu(rcu_data, i).mynode = &rnp[j]; \
 		(rsp)->rda[i] = &per_cpu(rcu_data, i); \
+		rcu_boot_init_percpu_data(i, rsp); \
 	} \
 } while (0)
 
-static struct notifier_block __cpuinitdata rcu_nb = {
-	.notifier_call	= rcu_cpu_notify,
-};
+#ifdef CONFIG_TREE_PREEMPT_RCU
+
+void __init __rcu_init_preempt(void)
+{
+	int i;			/* All used by RCU_INIT_FLAVOR(). */
+	int j;
+	struct rcu_node *rnp;
+
+	RCU_INIT_FLAVOR(&rcu_preempt_state, rcu_preempt_data);
+}
+
+#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+
+void __init __rcu_init_preempt(void)
+{
+}
+
+#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */
 
 void __init __rcu_init(void)
 {
-	int i;			/* All used by RCU_DATA_PTR_INIT(). */
+	int i;			/* All used by RCU_INIT_FLAVOR(). */
 	int j;
 	struct rcu_node *rnp;
 
-	printk(KERN_INFO "Hierarchical RCU implementation.\n");
+	rcu_bootup_announce();
 #ifdef CONFIG_RCU_CPU_STALL_DETECTOR
 	printk(KERN_INFO "RCU-based detection of stalled CPUs is enabled.\n");
 #endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
-	rcu_init_one(&rcu_state);
-	RCU_DATA_PTR_INIT(&rcu_state, rcu_data);
-	rcu_init_one(&rcu_bh_state);
-	RCU_DATA_PTR_INIT(&rcu_bh_state, rcu_bh_data);
-
-	for_each_online_cpu(i)
-		rcu_cpu_notify(&rcu_nb, CPU_UP_PREPARE, (void *)(long)i);
-	/* Register notifier for non-boot CPUs */
-	register_cpu_notifier(&rcu_nb);
+	RCU_INIT_FLAVOR(&rcu_sched_state, rcu_sched_data);
+	RCU_INIT_FLAVOR(&rcu_bh_state, rcu_bh_data);
+	__rcu_init_preempt();
+	open_softirq(RCU_SOFTIRQ, rcu_process_callbacks);
 }
 
 module_param(blimit, int, 0);
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index 5e872bb..8e8287a 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -1,10 +1,259 @@
+/*
+ * Read-Copy Update mechanism for mutual exclusion (tree-based version)
+ * Internal non-public definitions.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright IBM Corporation, 2008
+ *
+ * Author: Ingo Molnar <mingo@elte.hu>
+ *	   Paul E. McKenney <paulmck@linux.vnet.ibm.com>
+ */
+
+#include <linux/cache.h>
+#include <linux/spinlock.h>
+#include <linux/threads.h>
+#include <linux/cpumask.h>
+#include <linux/seqlock.h>
+
+/*
+ * Define shape of hierarchy based on NR_CPUS and CONFIG_RCU_FANOUT.
+ * In theory, it should be possible to add more levels straightforwardly.
+ * In practice, this has not been tested, so there is probably some
+ * bug somewhere.
+ */
+#define MAX_RCU_LVLS 3
+#define RCU_FANOUT	      (CONFIG_RCU_FANOUT)
+#define RCU_FANOUT_SQ	      (RCU_FANOUT * RCU_FANOUT)
+#define RCU_FANOUT_CUBE	      (RCU_FANOUT_SQ * RCU_FANOUT)
+
+#if NR_CPUS <= RCU_FANOUT
+#  define NUM_RCU_LVLS	      1
+#  define NUM_RCU_LVL_0	      1
+#  define NUM_RCU_LVL_1	      (NR_CPUS)
+#  define NUM_RCU_LVL_2	      0
+#  define NUM_RCU_LVL_3	      0
+#elif NR_CPUS <= RCU_FANOUT_SQ
+#  define NUM_RCU_LVLS	      2
+#  define NUM_RCU_LVL_0	      1
+#  define NUM_RCU_LVL_1	      (((NR_CPUS) + RCU_FANOUT - 1) / RCU_FANOUT)
+#  define NUM_RCU_LVL_2	      (NR_CPUS)
+#  define NUM_RCU_LVL_3	      0
+#elif NR_CPUS <= RCU_FANOUT_CUBE
+#  define NUM_RCU_LVLS	      3
+#  define NUM_RCU_LVL_0	      1
+#  define NUM_RCU_LVL_1	      (((NR_CPUS) + RCU_FANOUT_SQ - 1) / RCU_FANOUT_SQ)
+#  define NUM_RCU_LVL_2	      (((NR_CPUS) + (RCU_FANOUT) - 1) / (RCU_FANOUT))
+#  define NUM_RCU_LVL_3	      NR_CPUS
+#else
+# error "CONFIG_RCU_FANOUT insufficient for NR_CPUS"
+#endif /* #if (NR_CPUS) <= RCU_FANOUT */
+
+#define RCU_SUM (NUM_RCU_LVL_0 + NUM_RCU_LVL_1 + NUM_RCU_LVL_2 + NUM_RCU_LVL_3)
+#define NUM_RCU_NODES (RCU_SUM - NR_CPUS)
+
+/*
+ * Dynticks per-CPU state.
+ */
+struct rcu_dynticks {
+	int dynticks_nesting;	/* Track nesting level, sort of. */
+	int dynticks;		/* Even value for dynticks-idle, else odd. */
+	int dynticks_nmi;	/* Even value for either dynticks-idle or */
+				/*  not in nmi handler, else odd.  So this */
+				/*  remains even for nmi from irq handler. */
+};
+
+/*
+ * Definition for node within the RCU grace-period-detection hierarchy.
+ */
+struct rcu_node {
+	spinlock_t lock;
+	long	gpnum;		/* Current grace period for this node. */
+				/*  This will either be equal to or one */
+				/*  behind the root rcu_node's gpnum. */
+	unsigned long qsmask;	/* CPUs or groups that need to switch in */
+				/*  order for current grace period to proceed.*/
+	unsigned long qsmaskinit;
+				/* Per-GP initialization for qsmask. */
+	unsigned long grpmask;	/* Mask to apply to parent qsmask. */
+	int	grplo;		/* lowest-numbered CPU or group here. */
+	int	grphi;		/* highest-numbered CPU or group here. */
+	u8	grpnum;		/* CPU/group number for next level up. */
+	u8	level;		/* root is at level 0. */
+	struct rcu_node *parent;
+	struct list_head blocked_tasks[2];
+				/* Tasks blocked in RCU read-side critsect. */
+} ____cacheline_internodealigned_in_smp;
+
+/* Index values for nxttail array in struct rcu_data. */
+#define RCU_DONE_TAIL		0	/* Also RCU_WAIT head. */
+#define RCU_WAIT_TAIL		1	/* Also RCU_NEXT_READY head. */
+#define RCU_NEXT_READY_TAIL	2	/* Also RCU_NEXT head. */
+#define RCU_NEXT_TAIL		3
+#define RCU_NEXT_SIZE		4
+
+/* Per-CPU data for read-copy update. */
+struct rcu_data {
+	/* 1) quiescent-state and grace-period handling : */
+	long		completed;	/* Track rsp->completed gp number */
+					/*  in order to detect GP end. */
+	long		gpnum;		/* Highest gp number that this CPU */
+					/*  is aware of having started. */
+	long		passed_quiesc_completed;
+					/* Value of completed at time of qs. */
+	bool		passed_quiesc;	/* User-mode/idle loop etc. */
+	bool		qs_pending;	/* Core waits for quiesc state. */
+	bool		beenonline;	/* CPU online at least once. */
+	bool		preemptable;	/* Preemptable RCU? */
+	struct rcu_node *mynode;	/* This CPU's leaf of hierarchy */
+	unsigned long grpmask;		/* Mask to apply to leaf qsmask. */
+
+	/* 2) batch handling */
+	/*
+	 * If nxtlist is not NULL, it is partitioned as follows.
+	 * Any of the partitions might be empty, in which case the
+	 * pointer to that partition will be equal to the pointer for
+	 * the following partition.  When the list is empty, all of
+	 * the nxttail elements point to nxtlist, which is NULL.
+	 *
+	 * [*nxttail[RCU_NEXT_READY_TAIL], NULL = *nxttail[RCU_NEXT_TAIL]):
+	 *	Entries that might have arrived after current GP ended
+	 * [*nxttail[RCU_WAIT_TAIL], *nxttail[RCU_NEXT_READY_TAIL]):
+	 *	Entries known to have arrived before current GP ended
+	 * [*nxttail[RCU_DONE_TAIL], *nxttail[RCU_WAIT_TAIL]):
+	 *	Entries that batch # <= ->completed - 1: waiting for current GP
+	 * [nxtlist, *nxttail[RCU_DONE_TAIL]):
+	 *	Entries that batch # <= ->completed
+	 *	The grace period for these entries has completed, and
+	 *	the other grace-period-completed entries may be moved
+	 *	here temporarily in rcu_process_callbacks().
+	 */
+	struct rcu_head *nxtlist;
+	struct rcu_head **nxttail[RCU_NEXT_SIZE];
+	long		qlen;		/* # of queued callbacks */
+	long		blimit;		/* Upper limit on a processed batch */
+
+#ifdef CONFIG_NO_HZ
+	/* 3) dynticks interface. */
+	struct rcu_dynticks *dynticks;	/* Shared per-CPU dynticks state. */
+	int dynticks_snap;		/* Per-GP tracking for dynticks. */
+	int dynticks_nmi_snap;		/* Per-GP tracking for dynticks_nmi. */
+#endif /* #ifdef CONFIG_NO_HZ */
+
+	/* 4) reasons this CPU needed to be kicked by force_quiescent_state */
+#ifdef CONFIG_NO_HZ
+	unsigned long dynticks_fqs;	/* Kicked due to dynticks idle. */
+#endif /* #ifdef CONFIG_NO_HZ */
+	unsigned long offline_fqs;	/* Kicked due to being offline. */
+	unsigned long resched_ipi;	/* Sent a resched IPI. */
+
+	/* 5) __rcu_pending() statistics. */
+	long n_rcu_pending;		/* rcu_pending() calls since boot. */
+	long n_rp_qs_pending;
+	long n_rp_cb_ready;
+	long n_rp_cpu_needs_gp;
+	long n_rp_gp_completed;
+	long n_rp_gp_started;
+	long n_rp_need_fqs;
+	long n_rp_need_nothing;
+
+	int cpu;
+};
+
+/* Values for signaled field in struct rcu_state. */
+#define RCU_GP_INIT		0	/* Grace period being initialized. */
+#define RCU_SAVE_DYNTICK	1	/* Need to scan dyntick state. */
+#define RCU_FORCE_QS		2	/* Need to force quiescent state. */
+#ifdef CONFIG_NO_HZ
+#define RCU_SIGNAL_INIT		RCU_SAVE_DYNTICK
+#else /* #ifdef CONFIG_NO_HZ */
+#define RCU_SIGNAL_INIT		RCU_FORCE_QS
+#endif /* #else #ifdef CONFIG_NO_HZ */
+
+#define RCU_JIFFIES_TILL_FORCE_QS	 3	/* for rsp->jiffies_force_qs */
+#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
+#define RCU_SECONDS_TILL_STALL_CHECK   (10 * HZ)  /* for rsp->jiffies_stall */
+#define RCU_SECONDS_TILL_STALL_RECHECK (30 * HZ)  /* for rsp->jiffies_stall */
+#define RCU_STALL_RAT_DELAY		2	  /* Allow other CPUs time */
+						  /*  to take at least one */
+						  /*  scheduling clock irq */
+						  /*  before ratting on them. */
+
+#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
+
+/*
+ * RCU global state, including node hierarchy.  This hierarchy is
+ * represented in "heap" form in a dense array.  The root (first level)
+ * of the hierarchy is in ->node[0] (referenced by ->level[0]), the second
+ * level in ->node[1] through ->node[m] (->node[1] referenced by ->level[1]),
+ * and the third level in ->node[m+1] and following (->node[m+1] referenced
+ * by ->level[2]).  The number of levels is determined by the number of
+ * CPUs and by CONFIG_RCU_FANOUT.  Small systems will have a "hierarchy"
+ * consisting of a single rcu_node.
+ */
+struct rcu_state {
+	struct rcu_node node[NUM_RCU_NODES];	/* Hierarchy. */
+	struct rcu_node *level[NUM_RCU_LVLS];	/* Hierarchy levels. */
+	u32 levelcnt[MAX_RCU_LVLS + 1];		/* # nodes in each level. */
+	u8 levelspread[NUM_RCU_LVLS];		/* kids/node in each level. */
+	struct rcu_data *rda[NR_CPUS];		/* array of rdp pointers. */
+
+	/* The following fields are guarded by the root rcu_node's lock. */
+
+	u8	signaled ____cacheline_internodealigned_in_smp;
+						/* Force QS state. */
+	long	gpnum;				/* Current gp number. */
+	long	completed;			/* # of last completed gp. */
+	spinlock_t onofflock;			/* exclude on/offline and */
+						/*  starting new GP. */
+	spinlock_t fqslock;			/* Only one task forcing */
+						/*  quiescent states. */
+	unsigned long jiffies_force_qs;		/* Time at which to invoke */
+						/*  force_quiescent_state(). */
+	unsigned long n_force_qs;		/* Number of calls to */
+						/*  force_quiescent_state(). */
+	unsigned long n_force_qs_lh;		/* ~Number of calls leaving */
+						/*  due to lock unavailable. */
+	unsigned long n_force_qs_ngp;		/* Number of calls leaving */
+						/*  due to no GP active. */
+#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
+	unsigned long gp_start;			/* Time at which GP started, */
+						/*  but in jiffies. */
+	unsigned long jiffies_stall;		/* Time at which to check */
+						/*  for CPU stalls. */
+#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
+#ifdef CONFIG_NO_HZ
+	long dynticks_completed;		/* Value of completed @ snap. */
+#endif /* #ifdef CONFIG_NO_HZ */
+};
+
+#ifdef RCU_TREE_NONCORE
 
 /*
  * RCU implementation internal declarations:
  */
-extern struct rcu_state rcu_state;
-DECLARE_PER_CPU(struct rcu_data, rcu_data);
+extern struct rcu_state rcu_sched_state;
+DECLARE_PER_CPU(struct rcu_data, rcu_sched_data);
 
 extern struct rcu_state rcu_bh_state;
 DECLARE_PER_CPU(struct rcu_data, rcu_bh_data);
 
+#ifdef CONFIG_TREE_PREEMPT_RCU
+extern struct rcu_state rcu_preempt_state;
+DECLARE_PER_CPU(struct rcu_data, rcu_preempt_data);
+#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+
+#endif /* #ifdef RCU_TREE_NONCORE */
+
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
new file mode 100644
index 0000000..1cee04f
--- /dev/null
+++ b/kernel/rcutree_plugin.h
@@ -0,0 +1,566 @@
+/*
+ * Read-Copy Update mechanism for mutual exclusion (tree-based version)
+ * Internal non-public definitions that provide either classic
+ * or preemptable semantics.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright Red Hat, 2009
+ * Copyright IBM Corporation, 2009
+ *
+ * Author: Ingo Molnar <mingo@elte.hu>
+ *	   Paul E. McKenney <paulmck@linux.vnet.ibm.com>
+ */
+
+
+#ifdef CONFIG_TREE_PREEMPT_RCU
+
+struct rcu_state rcu_preempt_state = RCU_STATE_INITIALIZER(rcu_preempt_state);
+DEFINE_PER_CPU(struct rcu_data, rcu_preempt_data);
+
+/*
+ * Tell them what RCU they are running.
+ */
+static inline void rcu_bootup_announce(void)
+{
+	printk(KERN_INFO
+	       "Experimental preemptable hierarchical RCU implementation.\n");
+}
+
+/*
+ * Return the number of RCU-preempt batches processed thus far
+ * for debug and statistics.
+ */
+long rcu_batches_completed_preempt(void)
+{
+	return rcu_preempt_state.completed;
+}
+EXPORT_SYMBOL_GPL(rcu_batches_completed_preempt);
+
+/*
+ * Return the number of RCU batches processed thus far for debug & stats.
+ */
+long rcu_batches_completed(void)
+{
+	return rcu_batches_completed_preempt();
+}
+EXPORT_SYMBOL_GPL(rcu_batches_completed);
+
+/*
+ * Record a preemptable-RCU quiescent state for the specified CPU.  Note
+ * that this just means that the task currently running on the CPU is
+ * not in a quiescent state.  There might be any number of tasks blocked
+ * while in an RCU read-side critical section.
+ */
+static void rcu_preempt_qs(int cpu)
+{
+	struct rcu_data *rdp = &per_cpu(rcu_preempt_data, cpu);
+	rdp->passed_quiesc_completed = rdp->completed;
+	barrier();
+	rdp->passed_quiesc = 1;
+}
+
+/*
+ * We have entered the scheduler, and the current task might soon be
+ * context-switched away from.  If this task is in an RCU read-side
+ * critical section, we will no longer be able to rely on the CPU to
+ * record that fact, so we enqueue the task on the appropriate entry
+ * of the blocked_tasks[] array.  The task will dequeue itself when
+ * it exits the outermost enclosing RCU read-side critical section.
+ * Therefore, the current grace period cannot be permitted to complete
+ * until the blocked_tasks[] entry indexed by the low-order bit of
+ * rnp->gpnum empties.
+ *
+ * Caller must disable preemption.
+ */
+static void rcu_preempt_note_context_switch(int cpu)
+{
+	struct task_struct *t = current;
+	unsigned long flags;
+	int phase;
+	struct rcu_data *rdp;
+	struct rcu_node *rnp;
+
+	if (t->rcu_read_lock_nesting &&
+	    (t->rcu_read_unlock_special & RCU_READ_UNLOCK_BLOCKED) == 0) {
+
+		/* Possibly blocking in an RCU read-side critical section. */
+		rdp = rcu_preempt_state.rda[cpu];
+		rnp = rdp->mynode;
+		spin_lock_irqsave(&rnp->lock, flags);
+		t->rcu_read_unlock_special |= RCU_READ_UNLOCK_BLOCKED;
+		t->rcu_blocked_node = rnp;
+
+		/*
+		 * If this CPU has already checked in, then this task
+		 * will hold up the next grace period rather than the
+		 * current grace period.  Queue the task accordingly.
+		 * If the task is queued for the current grace period
+		 * (i.e., this CPU has not yet passed through a quiescent
+		 * state for the current grace period), then as long
+		 * as that task remains queued, the current grace period
+		 * cannot end.
+		 *
+		 * But first, note that the current CPU must still be
+		 * on line!
+		 */
+		WARN_ON_ONCE((rdp->grpmask & rnp->qsmaskinit) == 0);
+		WARN_ON_ONCE(!list_empty(&t->rcu_node_entry));
+		phase = (rnp->gpnum + !(rnp->qsmask & rdp->grpmask)) & 0x1;
+		list_add(&t->rcu_node_entry, &rnp->blocked_tasks[phase]);
+		spin_unlock_irqrestore(&rnp->lock, flags);
+	}
+
+	/*
+	 * Either we were not in an RCU read-side critical section to
+	 * begin with, or we have now recorded that critical section
+	 * globally.  Either way, we can now note a quiescent state
+	 * for this CPU.  Again, if we were in an RCU read-side critical
+	 * section, and if that critical section was blocking the current
+	 * grace period, then the fact that the task has been enqueued
+	 * means that we continue to block the current grace period.
+	 */
+	rcu_preempt_qs(cpu);
+	local_irq_save(flags);
+	t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
+	local_irq_restore(flags);
+}
+
+/*
+ * Tree-preemptable RCU implementation for rcu_read_lock().
+ * Just increment ->rcu_read_lock_nesting, shared state will be updated
+ * if we block.
+ */
+void __rcu_read_lock(void)
+{
+	ACCESS_ONCE(current->rcu_read_lock_nesting)++;
+	barrier();  /* needed if we ever invoke rcu_read_lock in rcutree.c */
+}
+EXPORT_SYMBOL_GPL(__rcu_read_lock);
+
+static void rcu_read_unlock_special(struct task_struct *t)
+{
+	int empty;
+	unsigned long flags;
+	unsigned long mask;
+	struct rcu_node *rnp;
+	int special;
+
+	/* NMI handlers cannot block and cannot safely manipulate state. */
+	if (in_nmi())
+		return;
+
+	local_irq_save(flags);
+
+	/*
+	 * If RCU core is waiting for this CPU to exit critical section,
+	 * let it know that we have done so.
+	 */
+	special = t->rcu_read_unlock_special;
+	if (special & RCU_READ_UNLOCK_NEED_QS) {
+		t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
+		rcu_preempt_qs(smp_processor_id());
+	}
+
+	/* Hardware IRQ handlers cannot block. */
+	if (in_irq()) {
+		local_irq_restore(flags);
+		return;
+	}
+
+	/* Clean up if blocked during RCU read-side critical section. */
+	if (special & RCU_READ_UNLOCK_BLOCKED) {
+		t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_BLOCKED;
+
+		/*
+		 * Remove this task from the list it blocked on.  The
+		 * task can migrate while we acquire the lock, but at
+		 * most one time.  So at most two passes through loop.
+		 */
+		for (;;) {
+			rnp = t->rcu_blocked_node;
+			spin_lock(&rnp->lock);  /* irqs already disabled. */
+			if (rnp == t->rcu_blocked_node)
+				break;
+			spin_unlock(&rnp->lock);  /* irqs remain disabled. */
+		}
+		empty = list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]);
+		list_del_init(&t->rcu_node_entry);
+		t->rcu_blocked_node = NULL;
+
+		/*
+		 * If this was the last task on the current list, and if
+		 * we aren't waiting on any CPUs, report the quiescent state.
+		 * Note that both cpu_quiet_msk_finish() and cpu_quiet_msk()
+		 * drop rnp->lock and restore irq.
+		 */
+		if (!empty && rnp->qsmask == 0 &&
+		    list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1])) {
+			struct rcu_node *rnp_p;
+
+			if (rnp->parent == NULL) {
+				/* Only one rcu_node in the tree. */
+				cpu_quiet_msk_finish(&rcu_preempt_state, flags);
+				return;
+			}
+			/* Report up the rest of the hierarchy. */
+			mask = rnp->grpmask;
+			spin_unlock_irqrestore(&rnp->lock, flags);
+			rnp_p = rnp->parent;
+			spin_lock_irqsave(&rnp_p->lock, flags);
+			WARN_ON_ONCE(rnp->qsmask);
+			cpu_quiet_msk(mask, &rcu_preempt_state, rnp_p, flags);
+			return;
+		}
+		spin_unlock(&rnp->lock);
+	}
+	local_irq_restore(flags);
+}
+
+/*
+ * Tree-preemptable RCU implementation for rcu_read_unlock().
+ * Decrement ->rcu_read_lock_nesting.  If the result is zero (outermost
+ * rcu_read_unlock()) and ->rcu_read_unlock_special is non-zero, then
+ * invoke rcu_read_unlock_special() to clean up after a context switch
+ * in an RCU read-side critical section and other special cases.
+ */
+void __rcu_read_unlock(void)
+{
+	struct task_struct *t = current;
+
+	barrier();  /* needed if we ever invoke rcu_read_unlock in rcutree.c */
+	if (--ACCESS_ONCE(t->rcu_read_lock_nesting) == 0 &&
+	    unlikely(ACCESS_ONCE(t->rcu_read_unlock_special)))
+		rcu_read_unlock_special(t);
+}
+EXPORT_SYMBOL_GPL(__rcu_read_unlock);
+
+#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
+
+/*
+ * Scan the current list of tasks blocked within RCU read-side critical
+ * sections, printing out the tid of each.
+ */
+static void rcu_print_task_stall(struct rcu_node *rnp)
+{
+	unsigned long flags;
+	struct list_head *lp;
+	int phase = rnp->gpnum & 0x1;
+	struct task_struct *t;
+
+	if (!list_empty(&rnp->blocked_tasks[phase])) {
+		spin_lock_irqsave(&rnp->lock, flags);
+		phase = rnp->gpnum & 0x1; /* re-read under lock. */
+		lp = &rnp->blocked_tasks[phase];
+		list_for_each_entry(t, lp, rcu_node_entry)
+			printk(" P%d", t->pid);
+		spin_unlock_irqrestore(&rnp->lock, flags);
+	}
+}
+
+#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
+
+/*
+ * Check that the list of blocked tasks for the newly completed grace
+ * period is in fact empty.  It is a serious bug to complete a grace
+ * period that still has RCU readers blocked!  This function must be
+ * invoked -before- updating this rnp's ->gpnum, and the rnp's ->lock
+ * must be held by the caller.
+ */
+static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
+{
+	WARN_ON_ONCE(!list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]));
+	WARN_ON_ONCE(rnp->qsmask);
+}
+
+/*
+ * Check for preempted RCU readers for the specified rcu_node structure.
+ * If the caller needs a reliable answer, it must hold the rcu_node's
+ * >lock.
+ */
+static int rcu_preempted_readers(struct rcu_node *rnp)
+{
+	return !list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+/*
+ * Handle tasklist migration for case in which all CPUs covered by the
+ * specified rcu_node have gone offline.  Move them up to the root
+ * rcu_node.  The reason for not just moving them to the immediate
+ * parent is to remove the need for rcu_read_unlock_special() to
+ * make more than two attempts to acquire the target rcu_node's lock.
+ *
+ * The caller must hold rnp->lock with irqs disabled.
+ */
+static void rcu_preempt_offline_tasks(struct rcu_state *rsp,
+				      struct rcu_node *rnp,
+				      struct rcu_data *rdp)
+{
+	int i;
+	struct list_head *lp;
+	struct list_head *lp_root;
+	struct rcu_node *rnp_root = rcu_get_root(rsp);
+	struct task_struct *tp;
+
+	if (rnp == rnp_root) {
+		WARN_ONCE(1, "Last CPU thought to be offlined?");
+		return;  /* Shouldn't happen: at least one CPU online. */
+	}
+	WARN_ON_ONCE(rnp != rdp->mynode &&
+		     (!list_empty(&rnp->blocked_tasks[0]) ||
+		      !list_empty(&rnp->blocked_tasks[1])));
+
+	/*
+	 * Move tasks up to root rcu_node.  Rely on the fact that the
+	 * root rcu_node can be at most one ahead of the rest of the
+	 * rcu_nodes in terms of gp_num value.  This fact allows us to
+	 * move the blocked_tasks[] array directly, element by element.
+	 */
+	for (i = 0; i < 2; i++) {
+		lp = &rnp->blocked_tasks[i];
+		lp_root = &rnp_root->blocked_tasks[i];
+		while (!list_empty(lp)) {
+			tp = list_entry(lp->next, typeof(*tp), rcu_node_entry);
+			spin_lock(&rnp_root->lock); /* irqs already disabled */
+			list_del(&tp->rcu_node_entry);
+			tp->rcu_blocked_node = rnp_root;
+			list_add(&tp->rcu_node_entry, lp_root);
+			spin_unlock(&rnp_root->lock); /* irqs remain disabled */
+		}
+	}
+}
+
+/*
+ * Do CPU-offline processing for preemptable RCU.
+ */
+static void rcu_preempt_offline_cpu(int cpu)
+{
+	__rcu_offline_cpu(cpu, &rcu_preempt_state);
+}
+
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+
+/*
+ * Check for a quiescent state from the current CPU.  When a task blocks,
+ * the task is recorded in the corresponding CPU's rcu_node structure,
+ * which is checked elsewhere.
+ *
+ * Caller must disable hard irqs.
+ */
+static void rcu_preempt_check_callbacks(int cpu)
+{
+	struct task_struct *t = current;
+
+	if (t->rcu_read_lock_nesting == 0) {
+		t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
+		rcu_preempt_qs(cpu);
+		return;
+	}
+	if (per_cpu(rcu_preempt_data, cpu).qs_pending)
+		t->rcu_read_unlock_special |= RCU_READ_UNLOCK_NEED_QS;
+}
+
+/*
+ * Process callbacks for preemptable RCU.
+ */
+static void rcu_preempt_process_callbacks(void)
+{
+	__rcu_process_callbacks(&rcu_preempt_state,
+				&__get_cpu_var(rcu_preempt_data));
+}
+
+/*
+ * Queue a preemptable-RCU callback for invocation after a grace period.
+ */
+void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+{
+	__call_rcu(head, func, &rcu_preempt_state);
+}
+EXPORT_SYMBOL_GPL(call_rcu);
+
+/*
+ * Check to see if there is any immediate preemptable-RCU-related work
+ * to be done.
+ */
+static int rcu_preempt_pending(int cpu)
+{
+	return __rcu_pending(&rcu_preempt_state,
+			     &per_cpu(rcu_preempt_data, cpu));
+}
+
+/*
+ * Does preemptable RCU need the CPU to stay out of dynticks mode?
+ */
+static int rcu_preempt_needs_cpu(int cpu)
+{
+	return !!per_cpu(rcu_preempt_data, cpu).nxtlist;
+}
+
+/*
+ * Initialize preemptable RCU's per-CPU data.
+ */
+static void __cpuinit rcu_preempt_init_percpu_data(int cpu)
+{
+	rcu_init_percpu_data(cpu, &rcu_preempt_state, 1);
+}
+
+/*
+ * Check for a task exiting while in a preemptable-RCU read-side
+ * critical section, clean up if so.  No need to issue warnings,
+ * as debug_check_no_locks_held() already does this if lockdep
+ * is enabled.
+ */
+void exit_rcu(void)
+{
+	struct task_struct *t = current;
+
+	if (t->rcu_read_lock_nesting == 0)
+		return;
+	t->rcu_read_lock_nesting = 1;
+	rcu_read_unlock();
+}
+
+#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+
+/*
+ * Tell them what RCU they are running.
+ */
+static inline void rcu_bootup_announce(void)
+{
+	printk(KERN_INFO "Hierarchical RCU implementation.\n");
+}
+
+/*
+ * Return the number of RCU batches processed thus far for debug & stats.
+ */
+long rcu_batches_completed(void)
+{
+	return rcu_batches_completed_sched();
+}
+EXPORT_SYMBOL_GPL(rcu_batches_completed);
+
+/*
+ * Because preemptable RCU does not exist, we never have to check for
+ * CPUs being in quiescent states.
+ */
+static void rcu_preempt_note_context_switch(int cpu)
+{
+}
+
+#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
+
+/*
+ * Because preemptable RCU does not exist, we never have to check for
+ * tasks blocked within RCU read-side critical sections.
+ */
+static void rcu_print_task_stall(struct rcu_node *rnp)
+{
+}
+
+#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
+
+/*
+ * Because there is no preemptable RCU, there can be no readers blocked,
+ * so there is no need to check for blocked tasks.  So check only for
+ * bogus qsmask values.
+ */
+static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
+{
+	WARN_ON_ONCE(rnp->qsmask);
+}
+
+/*
+ * Because preemptable RCU does not exist, there are never any preempted
+ * RCU readers.
+ */
+static int rcu_preempted_readers(struct rcu_node *rnp)
+{
+	return 0;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+/*
+ * Because preemptable RCU does not exist, it never needs to migrate
+ * tasks that were blocked within RCU read-side critical sections.
+ */
+static void rcu_preempt_offline_tasks(struct rcu_state *rsp,
+				      struct rcu_node *rnp,
+				      struct rcu_data *rdp)
+{
+}
+
+/*
+ * Because preemptable RCU does not exist, it never needs CPU-offline
+ * processing.
+ */
+static void rcu_preempt_offline_cpu(int cpu)
+{
+}
+
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+
+/*
+ * Because preemptable RCU does not exist, it never has any callbacks
+ * to check.
+ */
+void rcu_preempt_check_callbacks(int cpu)
+{
+}
+
+/*
+ * Because preemptable RCU does not exist, it never has any callbacks
+ * to process.
+ */
+void rcu_preempt_process_callbacks(void)
+{
+}
+
+/*
+ * In classic RCU, call_rcu() is just call_rcu_sched().
+ */
+void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+{
+	call_rcu_sched(head, func);
+}
+EXPORT_SYMBOL_GPL(call_rcu);
+
+/*
+ * Because preemptable RCU does not exist, it never has any work to do.
+ */
+static int rcu_preempt_pending(int cpu)
+{
+	return 0;
+}
+
+/*
+ * Because preemptable RCU does not exist, it never needs any CPU.
+ */
+static int rcu_preempt_needs_cpu(int cpu)
+{
+	return 0;
+}
+
+/*
+ * Because preemptable RCU does not exist, there is no per-CPU
+ * data to initialize.
+ */
+static void __cpuinit rcu_preempt_init_percpu_data(int cpu)
+{
+}
+
+#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */
diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c
index fe1dcdb..c89f5e9 100644
--- a/kernel/rcutree_trace.c
+++ b/kernel/rcutree_trace.c
@@ -20,7 +20,7 @@
  * Papers:  http://www.rdrop.com/users/paulmck/RCU
  *
  * For detailed explanation of Read-Copy Update mechanism see -
- * 		Documentation/RCU
+ *		Documentation/RCU
  *
  */
 #include <linux/types.h>
@@ -43,6 +43,7 @@
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 
+#define RCU_TREE_NONCORE
 #include "rcutree.h"
 
 static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
@@ -76,8 +77,12 @@ static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
 
 static int show_rcudata(struct seq_file *m, void *unused)
 {
-	seq_puts(m, "rcu:\n");
-	PRINT_RCU_DATA(rcu_data, print_one_rcu_data, m);
+#ifdef CONFIG_TREE_PREEMPT_RCU
+	seq_puts(m, "rcu_preempt:\n");
+	PRINT_RCU_DATA(rcu_preempt_data, print_one_rcu_data, m);
+#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+	seq_puts(m, "rcu_sched:\n");
+	PRINT_RCU_DATA(rcu_sched_data, print_one_rcu_data, m);
 	seq_puts(m, "rcu_bh:\n");
 	PRINT_RCU_DATA(rcu_bh_data, print_one_rcu_data, m);
 	return 0;
@@ -102,7 +107,7 @@ static void print_one_rcu_data_csv(struct seq_file *m, struct rcu_data *rdp)
 		return;
 	seq_printf(m, "%d,%s,%ld,%ld,%d,%ld,%d",
 		   rdp->cpu,
-		   cpu_is_offline(rdp->cpu) ? "\"Y\"" : "\"N\"",
+		   cpu_is_offline(rdp->cpu) ? "\"N\"" : "\"Y\"",
 		   rdp->completed, rdp->gpnum,
 		   rdp->passed_quiesc, rdp->passed_quiesc_completed,
 		   rdp->qs_pending);
@@ -124,8 +129,12 @@ static int show_rcudata_csv(struct seq_file *m, void *unused)
 	seq_puts(m, "\"dt\",\"dt nesting\",\"dn\",\"df\",");
 #endif /* #ifdef CONFIG_NO_HZ */
 	seq_puts(m, "\"of\",\"ri\",\"ql\",\"b\"\n");
-	seq_puts(m, "\"rcu:\"\n");
-	PRINT_RCU_DATA(rcu_data, print_one_rcu_data_csv, m);
+#ifdef CONFIG_TREE_PREEMPT_RCU
+	seq_puts(m, "\"rcu_preempt:\"\n");
+	PRINT_RCU_DATA(rcu_preempt_data, print_one_rcu_data_csv, m);
+#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+	seq_puts(m, "\"rcu_sched:\"\n");
+	PRINT_RCU_DATA(rcu_sched_data, print_one_rcu_data_csv, m);
 	seq_puts(m, "\"rcu_bh:\"\n");
 	PRINT_RCU_DATA(rcu_bh_data, print_one_rcu_data_csv, m);
 	return 0;
@@ -171,8 +180,12 @@ static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp)
 
 static int show_rcuhier(struct seq_file *m, void *unused)
 {
-	seq_puts(m, "rcu:\n");
-	print_one_rcu_state(m, &rcu_state);
+#ifdef CONFIG_TREE_PREEMPT_RCU
+	seq_puts(m, "rcu_preempt:\n");
+	print_one_rcu_state(m, &rcu_preempt_state);
+#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+	seq_puts(m, "rcu_sched:\n");
+	print_one_rcu_state(m, &rcu_sched_state);
 	seq_puts(m, "rcu_bh:\n");
 	print_one_rcu_state(m, &rcu_bh_state);
 	return 0;
@@ -193,8 +206,12 @@ static struct file_operations rcuhier_fops = {
 
 static int show_rcugp(struct seq_file *m, void *unused)
 {
-	seq_printf(m, "rcu: completed=%ld  gpnum=%ld\n",
-		   rcu_state.completed, rcu_state.gpnum);
+#ifdef CONFIG_TREE_PREEMPT_RCU
+	seq_printf(m, "rcu_preempt: completed=%ld  gpnum=%ld\n",
+		   rcu_preempt_state.completed, rcu_preempt_state.gpnum);
+#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+	seq_printf(m, "rcu_sched: completed=%ld  gpnum=%ld\n",
+		   rcu_sched_state.completed, rcu_sched_state.gpnum);
 	seq_printf(m, "rcu_bh: completed=%ld  gpnum=%ld\n",
 		   rcu_bh_state.completed, rcu_bh_state.gpnum);
 	return 0;
@@ -243,8 +260,12 @@ static void print_rcu_pendings(struct seq_file *m, struct rcu_state *rsp)
 
 static int show_rcu_pending(struct seq_file *m, void *unused)
 {
-	seq_puts(m, "rcu:\n");
-	print_rcu_pendings(m, &rcu_state);
+#ifdef CONFIG_TREE_PREEMPT_RCU
+	seq_puts(m, "rcu_preempt:\n");
+	print_rcu_pendings(m, &rcu_preempt_state);
+#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+	seq_puts(m, "rcu_sched:\n");
+	print_rcu_pendings(m, &rcu_sched_state);
 	seq_puts(m, "rcu_bh:\n");
 	print_rcu_pendings(m, &rcu_bh_state);
 	return 0;
@@ -264,62 +285,47 @@ static struct file_operations rcu_pending_fops = {
 };
 
 static struct dentry *rcudir;
-static struct dentry *datadir;
-static struct dentry *datadir_csv;
-static struct dentry *gpdir;
-static struct dentry *hierdir;
-static struct dentry *rcu_pendingdir;
 
 static int __init rcuclassic_trace_init(void)
 {
+	struct dentry *retval;
+
 	rcudir = debugfs_create_dir("rcu", NULL);
 	if (!rcudir)
-		goto out;
+		goto free_out;
 
-	datadir = debugfs_create_file("rcudata", 0444, rcudir,
+	retval = debugfs_create_file("rcudata", 0444, rcudir,
 						NULL, &rcudata_fops);
-	if (!datadir)
+	if (!retval)
 		goto free_out;
 
-	datadir_csv = debugfs_create_file("rcudata.csv", 0444, rcudir,
+	retval = debugfs_create_file("rcudata.csv", 0444, rcudir,
 						NULL, &rcudata_csv_fops);
-	if (!datadir_csv)
+	if (!retval)
 		goto free_out;
 
-	gpdir = debugfs_create_file("rcugp", 0444, rcudir, NULL, &rcugp_fops);
-	if (!gpdir)
+	retval = debugfs_create_file("rcugp", 0444, rcudir, NULL, &rcugp_fops);
+	if (!retval)
 		goto free_out;
 
-	hierdir = debugfs_create_file("rcuhier", 0444, rcudir,
+	retval = debugfs_create_file("rcuhier", 0444, rcudir,
 						NULL, &rcuhier_fops);
-	if (!hierdir)
+	if (!retval)
 		goto free_out;
 
-	rcu_pendingdir = debugfs_create_file("rcu_pending", 0444, rcudir,
+	retval = debugfs_create_file("rcu_pending", 0444, rcudir,
 						NULL, &rcu_pending_fops);
-	if (!rcu_pendingdir)
+	if (!retval)
 		goto free_out;
 	return 0;
 free_out:
-	if (datadir)
-		debugfs_remove(datadir);
-	if (datadir_csv)
-		debugfs_remove(datadir_csv);
-	if (gpdir)
-		debugfs_remove(gpdir);
-	debugfs_remove(rcudir);
-out:
+	debugfs_remove_recursive(rcudir);
 	return 1;
 }
 
 static void __exit rcuclassic_trace_cleanup(void)
 {
-	debugfs_remove(datadir);
-	debugfs_remove(datadir_csv);
-	debugfs_remove(gpdir);
-	debugfs_remove(hierdir);
-	debugfs_remove(rcu_pendingdir);
-	debugfs_remove(rcudir);
+	debugfs_remove_recursive(rcudir);
 }
 
 
diff --git a/kernel/resource.c b/kernel/resource.c
index 78b0872..fb11a58 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -223,13 +223,13 @@ int release_resource(struct resource *old)
 
 EXPORT_SYMBOL(release_resource);
 
-#if defined(CONFIG_MEMORY_HOTPLUG) && !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
+#if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
 /*
  * Finds the lowest memory reosurce exists within [res->start.res->end)
- * the caller must specify res->start, res->end, res->flags.
+ * the caller must specify res->start, res->end, res->flags and "name".
  * If found, returns 0, res is overwritten, if not found, returns -1.
  */
-static int find_next_system_ram(struct resource *res)
+static int find_next_system_ram(struct resource *res, char *name)
 {
 	resource_size_t start, end;
 	struct resource *p;
@@ -245,6 +245,8 @@ static int find_next_system_ram(struct resource *res)
 		/* system ram is just marked as IORESOURCE_MEM */
 		if (p->flags != res->flags)
 			continue;
+		if (name && strcmp(p->name, name))
+			continue;
 		if (p->start > end) {
 			p = NULL;
 			break;
@@ -262,19 +264,26 @@ static int find_next_system_ram(struct resource *res)
 		res->end = p->end;
 	return 0;
 }
-int
-walk_memory_resource(unsigned long start_pfn, unsigned long nr_pages, void *arg,
-			int (*func)(unsigned long, unsigned long, void *))
+
+/*
+ * This function calls callback against all memory range of "System RAM"
+ * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY.
+ * Now, this function is only for "System RAM".
+ */
+int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
+		void *arg, int (*func)(unsigned long, unsigned long, void *))
 {
 	struct resource res;
 	unsigned long pfn, len;
 	u64 orig_end;
 	int ret = -1;
+
 	res.start = (u64) start_pfn << PAGE_SHIFT;
 	res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
 	res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 	orig_end = res.end;
-	while ((res.start < res.end) && (find_next_system_ram(&res) >= 0)) {
+	while ((res.start < res.end) &&
+		(find_next_system_ram(&res, "System RAM") >= 0)) {
 		pfn = (unsigned long)(res.start >> PAGE_SHIFT);
 		len = (unsigned long)((res.end + 1 - res.start) >> PAGE_SHIFT);
 		ret = (*func)(pfn, len, arg);
diff --git a/kernel/sched.c b/kernel/sched.c
index 1b59e26..2f76e06b 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -39,7 +39,7 @@
 #include <linux/completion.h>
 #include <linux/kernel_stat.h>
 #include <linux/debug_locks.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
 #include <linux/security.h>
 #include <linux/notifier.h>
 #include <linux/profile.h>
@@ -64,7 +64,6 @@
 #include <linux/tsacct_kern.h>
 #include <linux/kprobes.h>
 #include <linux/delayacct.h>
-#include <linux/reciprocal_div.h>
 #include <linux/unistd.h>
 #include <linux/pagemap.h>
 #include <linux/hrtimer.h>
@@ -120,30 +119,6 @@
  */
 #define RUNTIME_INF	((u64)~0ULL)
 
-#ifdef CONFIG_SMP
-
-static void double_rq_lock(struct rq *rq1, struct rq *rq2);
-
-/*
- * Divide a load by a sched group cpu_power : (load / sg->__cpu_power)
- * Since cpu_power is a 'constant', we can use a reciprocal divide.
- */
-static inline u32 sg_div_cpu_power(const struct sched_group *sg, u32 load)
-{
-	return reciprocal_divide(load, sg->reciprocal_cpu_power);
-}
-
-/*
- * Each time a sched group cpu_power is changed,
- * we must compute its reciprocal value
- */
-static inline void sg_inc_cpu_power(struct sched_group *sg, u32 val)
-{
-	sg->__cpu_power += val;
-	sg->reciprocal_cpu_power = reciprocal_value(sg->__cpu_power);
-}
-#endif
-
 static inline int rt_policy(int policy)
 {
 	if (unlikely(policy == SCHED_FIFO || policy == SCHED_RR))
@@ -309,8 +284,8 @@ void set_tg_uid(struct user_struct *user)
 
 /*
  * Root task group.
- * 	Every UID task group (including init_task_group aka UID-0) will
- * 	be a child to this group.
+ *	Every UID task group (including init_task_group aka UID-0) will
+ *	be a child to this group.
  */
 struct task_group root_task_group;
 
@@ -318,12 +293,12 @@ struct task_group root_task_group;
 /* Default task group's sched entity on each cpu */
 static DEFINE_PER_CPU(struct sched_entity, init_sched_entity);
 /* Default task group's cfs_rq on each cpu */
-static DEFINE_PER_CPU(struct cfs_rq, init_cfs_rq) ____cacheline_aligned_in_smp;
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct cfs_rq, init_tg_cfs_rq);
 #endif /* CONFIG_FAIR_GROUP_SCHED */
 
 #ifdef CONFIG_RT_GROUP_SCHED
 static DEFINE_PER_CPU(struct sched_rt_entity, init_sched_rt_entity);
-static DEFINE_PER_CPU(struct rt_rq, init_rt_rq) ____cacheline_aligned_in_smp;
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct rt_rq, init_rt_rq);
 #endif /* CONFIG_RT_GROUP_SCHED */
 #else /* !CONFIG_USER_SCHED */
 #define root_task_group init_task_group
@@ -401,13 +376,6 @@ static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
 
 #else
 
-#ifdef CONFIG_SMP
-static int root_task_group_empty(void)
-{
-	return 1;
-}
-#endif
-
 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
 static inline struct task_group *task_group(struct task_struct *p)
 {
@@ -537,14 +505,6 @@ struct root_domain {
 #ifdef CONFIG_SMP
 	struct cpupri cpupri;
 #endif
-#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
-	/*
-	 * Preferred wake up cpu nominated by sched_mc balance that will be
-	 * used when most cpus are idle in the system indicating overall very
-	 * low system utilisation. Triggered at POWERSAVINGS_BALANCE_WAKEUP(2)
-	 */
-	unsigned int sched_mc_preferred_wakeup_cpu;
-#endif
 };
 
 /*
@@ -616,6 +576,7 @@ struct rq {
 
 	unsigned char idle_at_tick;
 	/* For active balancing */
+	int post_schedule;
 	int active_balance;
 	int push_cpu;
 	/* cpu of this runqueue: */
@@ -626,6 +587,9 @@ struct rq {
 
 	struct task_struct *migration_thread;
 	struct list_head migration_queue;
+
+	u64 rt_avg;
+	u64 age_stamp;
 #endif
 
 	/* calc_load related fields */
@@ -665,9 +629,10 @@ struct rq {
 
 static DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
 
-static inline void check_preempt_curr(struct rq *rq, struct task_struct *p, int sync)
+static inline
+void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags)
 {
-	rq->curr->sched_class->check_preempt_curr(rq, p, sync);
+	rq->curr->sched_class->check_preempt_curr(rq, p, flags);
 }
 
 static inline int cpu_of(struct rq *rq)
@@ -693,6 +658,7 @@ static inline int cpu_of(struct rq *rq)
 #define this_rq()		(&__get_cpu_var(runqueues))
 #define task_rq(p)		cpu_rq(task_cpu(p))
 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
+#define raw_rq()		(&__raw_get_cpu_var(runqueues))
 
 inline void update_rq_clock(struct rq *rq)
 {
@@ -715,15 +681,9 @@ inline void update_rq_clock(struct rq *rq)
  * This interface allows printk to be called with the runqueue lock
  * held and know whether or not it is OK to wake up the klogd.
  */
-int runqueue_is_locked(void)
+int runqueue_is_locked(int cpu)
 {
-	int cpu = get_cpu();
-	struct rq *rq = cpu_rq(cpu);
-	int ret;
-
-	ret = spin_is_locked(&rq->lock);
-	put_cpu();
-	return ret;
+	return spin_is_locked(&cpu_rq(cpu)->lock);
 }
 
 /*
@@ -861,6 +821,14 @@ unsigned int sysctl_sched_shares_ratelimit = 250000;
 unsigned int sysctl_sched_shares_thresh = 4;
 
 /*
+ * period over which we average the RT time consumption, measured
+ * in ms.
+ *
+ * default: 1s
+ */
+const_debug unsigned int sysctl_sched_time_avg = MSEC_PER_SEC;
+
+/*
  * period over which we measure -rt task cpu usage in us.
  * default: 1s
  */
@@ -1278,12 +1246,37 @@ void wake_up_idle_cpu(int cpu)
 }
 #endif /* CONFIG_NO_HZ */
 
+static u64 sched_avg_period(void)
+{
+	return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2;
+}
+
+static void sched_avg_update(struct rq *rq)
+{
+	s64 period = sched_avg_period();
+
+	while ((s64)(rq->clock - rq->age_stamp) > period) {
+		rq->age_stamp += period;
+		rq->rt_avg /= 2;
+	}
+}
+
+static void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
+{
+	rq->rt_avg += rt_delta;
+	sched_avg_update(rq);
+}
+
 #else /* !CONFIG_SMP */
 static void resched_task(struct task_struct *p)
 {
 	assert_spin_locked(&task_rq(p)->lock);
 	set_tsk_need_resched(p);
 }
+
+static void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
+{
+}
 #endif /* CONFIG_SMP */
 
 #if BITS_PER_LONG == 32
@@ -1494,8 +1487,65 @@ static int tg_nop(struct task_group *tg, void *data)
 #endif
 
 #ifdef CONFIG_SMP
-static unsigned long source_load(int cpu, int type);
-static unsigned long target_load(int cpu, int type);
+/* Used instead of source_load when we know the type == 0 */
+static unsigned long weighted_cpuload(const int cpu)
+{
+	return cpu_rq(cpu)->load.weight;
+}
+
+/*
+ * Return a low guess at the load of a migration-source cpu weighted
+ * according to the scheduling class and "nice" value.
+ *
+ * We want to under-estimate the load of migration sources, to
+ * balance conservatively.
+ */
+static unsigned long source_load(int cpu, int type)
+{
+	struct rq *rq = cpu_rq(cpu);
+	unsigned long total = weighted_cpuload(cpu);
+
+	if (type == 0 || !sched_feat(LB_BIAS))
+		return total;
+
+	return min(rq->cpu_load[type-1], total);
+}
+
+/*
+ * Return a high guess at the load of a migration-target cpu weighted
+ * according to the scheduling class and "nice" value.
+ */
+static unsigned long target_load(int cpu, int type)
+{
+	struct rq *rq = cpu_rq(cpu);
+	unsigned long total = weighted_cpuload(cpu);
+
+	if (type == 0 || !sched_feat(LB_BIAS))
+		return total;
+
+	return max(rq->cpu_load[type-1], total);
+}
+
+static struct sched_group *group_of(int cpu)
+{
+	struct sched_domain *sd = rcu_dereference(cpu_rq(cpu)->sd);
+
+	if (!sd)
+		return NULL;
+
+	return sd->groups;
+}
+
+static unsigned long power_of(int cpu)
+{
+	struct sched_group *group = group_of(cpu);
+
+	if (!group)
+		return SCHED_LOAD_SCALE;
+
+	return group->cpu_power;
+}
+
 static int task_hot(struct task_struct *p, u64 now, struct sched_domain *sd);
 
 static unsigned long cpu_avg_load_per_task(int cpu)
@@ -1513,28 +1563,35 @@ static unsigned long cpu_avg_load_per_task(int cpu)
 
 #ifdef CONFIG_FAIR_GROUP_SCHED
 
+struct update_shares_data {
+	unsigned long rq_weight[NR_CPUS];
+};
+
+static DEFINE_PER_CPU(struct update_shares_data, update_shares_data);
+
 static void __set_se_shares(struct sched_entity *se, unsigned long shares);
 
 /*
  * Calculate and set the cpu's group shares.
  */
-static void
-update_group_shares_cpu(struct task_group *tg, int cpu,
-			unsigned long sd_shares, unsigned long sd_rq_weight)
+static void update_group_shares_cpu(struct task_group *tg, int cpu,
+				    unsigned long sd_shares,
+				    unsigned long sd_rq_weight,
+				    struct update_shares_data *usd)
 {
-	unsigned long shares;
-	unsigned long rq_weight;
-
-	if (!tg->se[cpu])
-		return;
+	unsigned long shares, rq_weight;
+	int boost = 0;
 
-	rq_weight = tg->cfs_rq[cpu]->rq_weight;
+	rq_weight = usd->rq_weight[cpu];
+	if (!rq_weight) {
+		boost = 1;
+		rq_weight = NICE_0_LOAD;
+	}
 
 	/*
-	 *           \Sum shares * rq_weight
-	 * shares =  -----------------------
-	 *               \Sum rq_weight
-	 *
+	 *             \Sum_j shares_j * rq_weight_i
+	 * shares_i =  -----------------------------
+	 *                  \Sum_j rq_weight_j
 	 */
 	shares = (sd_shares * rq_weight) / sd_rq_weight;
 	shares = clamp_t(unsigned long, shares, MIN_SHARES, MAX_SHARES);
@@ -1545,8 +1602,8 @@ update_group_shares_cpu(struct task_group *tg, int cpu,
 		unsigned long flags;
 
 		spin_lock_irqsave(&rq->lock, flags);
-		tg->cfs_rq[cpu]->shares = shares;
-
+		tg->cfs_rq[cpu]->rq_weight = boost ? 0 : rq_weight;
+		tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
 		__set_se_shares(tg->se[cpu], shares);
 		spin_unlock_irqrestore(&rq->lock, flags);
 	}
@@ -1559,22 +1616,30 @@ update_group_shares_cpu(struct task_group *tg, int cpu,
  */
 static int tg_shares_up(struct task_group *tg, void *data)
 {
-	unsigned long weight, rq_weight = 0;
-	unsigned long shares = 0;
+	unsigned long weight, rq_weight = 0, shares = 0;
+	struct update_shares_data *usd;
 	struct sched_domain *sd = data;
+	unsigned long flags;
 	int i;
 
+	if (!tg->se[0])
+		return 0;
+
+	local_irq_save(flags);
+	usd = &__get_cpu_var(update_shares_data);
+
 	for_each_cpu(i, sched_domain_span(sd)) {
+		weight = tg->cfs_rq[i]->load.weight;
+		usd->rq_weight[i] = weight;
+
 		/*
 		 * If there are currently no tasks on the cpu pretend there
 		 * is one of average load so that when a new task gets to
 		 * run here it will not get delayed by group starvation.
 		 */
-		weight = tg->cfs_rq[i]->load.weight;
 		if (!weight)
 			weight = NICE_0_LOAD;
 
-		tg->cfs_rq[i]->rq_weight = weight;
 		rq_weight += weight;
 		shares += tg->cfs_rq[i]->shares;
 	}
@@ -1586,7 +1651,9 @@ static int tg_shares_up(struct task_group *tg, void *data)
 		shares = tg->shares;
 
 	for_each_cpu(i, sched_domain_span(sd))
-		update_group_shares_cpu(tg, i, shares, rq_weight);
+		update_group_shares_cpu(tg, i, shares, rq_weight, usd);
+
+	local_irq_restore(flags);
 
 	return 0;
 }
@@ -1616,8 +1683,14 @@ static int tg_load_down(struct task_group *tg, void *data)
 
 static void update_shares(struct sched_domain *sd)
 {
-	u64 now = cpu_clock(raw_smp_processor_id());
-	s64 elapsed = now - sd->last_update;
+	s64 elapsed;
+	u64 now;
+
+	if (root_task_group_empty())
+		return;
+
+	now = cpu_clock(raw_smp_processor_id());
+	elapsed = now - sd->last_update;
 
 	if (elapsed >= (s64)(u64)sysctl_sched_shares_ratelimit) {
 		sd->last_update = now;
@@ -1627,6 +1700,9 @@ static void update_shares(struct sched_domain *sd)
 
 static void update_shares_locked(struct rq *rq, struct sched_domain *sd)
 {
+	if (root_task_group_empty())
+		return;
+
 	spin_unlock(&rq->lock);
 	update_shares(sd);
 	spin_lock(&rq->lock);
@@ -1634,6 +1710,9 @@ static void update_shares_locked(struct rq *rq, struct sched_domain *sd)
 
 static void update_h_load(long cpu)
 {
+	if (root_task_group_empty())
+		return;
+
 	walk_tg_tree(tg_load_down, tg_nop, (void *)cpu);
 }
 
@@ -1651,6 +1730,8 @@ static inline void update_shares_locked(struct rq *rq, struct sched_domain *sd)
 
 #ifdef CONFIG_PREEMPT
 
+static void double_rq_lock(struct rq *rq1, struct rq *rq2);
+
 /*
  * fair double_lock_balance: Safely acquires both rq->locks in a fair
  * way at the expense of forcing extra atomic operations in all
@@ -1915,13 +1996,6 @@ static inline void check_class_changed(struct rq *rq, struct task_struct *p,
 }
 
 #ifdef CONFIG_SMP
-
-/* Used instead of source_load when we know the type == 0 */
-static unsigned long weighted_cpuload(const int cpu)
-{
-	return cpu_rq(cpu)->load.weight;
-}
-
 /*
  * Is this task likely cache-hot:
  */
@@ -1979,7 +2053,7 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
 		if (task_hot(p, old_rq->clock, NULL))
 			schedstat_inc(p, se.nr_forced2_migrations);
 #endif
-		perf_swcounter_event(PERF_COUNT_SW_CPU_MIGRATIONS,
+		perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS,
 				     1, 1, NULL, 0);
 	}
 	p->se.vruntime -= old_cfsrq->min_vruntime -
@@ -2195,186 +2269,6 @@ void kick_process(struct task_struct *p)
 	preempt_enable();
 }
 EXPORT_SYMBOL_GPL(kick_process);
-
-/*
- * Return a low guess at the load of a migration-source cpu weighted
- * according to the scheduling class and "nice" value.
- *
- * We want to under-estimate the load of migration sources, to
- * balance conservatively.
- */
-static unsigned long source_load(int cpu, int type)
-{
-	struct rq *rq = cpu_rq(cpu);
-	unsigned long total = weighted_cpuload(cpu);
-
-	if (type == 0 || !sched_feat(LB_BIAS))
-		return total;
-
-	return min(rq->cpu_load[type-1], total);
-}
-
-/*
- * Return a high guess at the load of a migration-target cpu weighted
- * according to the scheduling class and "nice" value.
- */
-static unsigned long target_load(int cpu, int type)
-{
-	struct rq *rq = cpu_rq(cpu);
-	unsigned long total = weighted_cpuload(cpu);
-
-	if (type == 0 || !sched_feat(LB_BIAS))
-		return total;
-
-	return max(rq->cpu_load[type-1], total);
-}
-
-/*
- * find_idlest_group finds and returns the least busy CPU group within the
- * domain.
- */
-static struct sched_group *
-find_idlest_group(struct sched_domain *sd, struct task_struct *p, int this_cpu)
-{
-	struct sched_group *idlest = NULL, *this = NULL, *group = sd->groups;
-	unsigned long min_load = ULONG_MAX, this_load = 0;
-	int load_idx = sd->forkexec_idx;
-	int imbalance = 100 + (sd->imbalance_pct-100)/2;
-
-	do {
-		unsigned long load, avg_load;
-		int local_group;
-		int i;
-
-		/* Skip over this group if it has no CPUs allowed */
-		if (!cpumask_intersects(sched_group_cpus(group),
-					&p->cpus_allowed))
-			continue;
-
-		local_group = cpumask_test_cpu(this_cpu,
-					       sched_group_cpus(group));
-
-		/* Tally up the load of all CPUs in the group */
-		avg_load = 0;
-
-		for_each_cpu(i, sched_group_cpus(group)) {
-			/* Bias balancing toward cpus of our domain */
-			if (local_group)
-				load = source_load(i, load_idx);
-			else
-				load = target_load(i, load_idx);
-
-			avg_load += load;
-		}
-
-		/* Adjust by relative CPU power of the group */
-		avg_load = sg_div_cpu_power(group,
-				avg_load * SCHED_LOAD_SCALE);
-
-		if (local_group) {
-			this_load = avg_load;
-			this = group;
-		} else if (avg_load < min_load) {
-			min_load = avg_load;
-			idlest = group;
-		}
-	} while (group = group->next, group != sd->groups);
-
-	if (!idlest || 100*this_load < imbalance*min_load)
-		return NULL;
-	return idlest;
-}
-
-/*
- * find_idlest_cpu - find the idlest cpu among the cpus in group.
- */
-static int
-find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
-{
-	unsigned long load, min_load = ULONG_MAX;
-	int idlest = -1;
-	int i;
-
-	/* Traverse only the allowed CPUs */
-	for_each_cpu_and(i, sched_group_cpus(group), &p->cpus_allowed) {
-		load = weighted_cpuload(i);
-
-		if (load < min_load || (load == min_load && i == this_cpu)) {
-			min_load = load;
-			idlest = i;
-		}
-	}
-
-	return idlest;
-}
-
-/*
- * sched_balance_self: balance the current task (running on cpu) in domains
- * that have the 'flag' flag set. In practice, this is SD_BALANCE_FORK and
- * SD_BALANCE_EXEC.
- *
- * Balance, ie. select the least loaded group.
- *
- * Returns the target CPU number, or the same CPU if no balancing is needed.
- *
- * preempt must be disabled.
- */
-static int sched_balance_self(int cpu, int flag)
-{
-	struct task_struct *t = current;
-	struct sched_domain *tmp, *sd = NULL;
-
-	for_each_domain(cpu, tmp) {
-		/*
-		 * If power savings logic is enabled for a domain, stop there.
-		 */
-		if (tmp->flags & SD_POWERSAVINGS_BALANCE)
-			break;
-		if (tmp->flags & flag)
-			sd = tmp;
-	}
-
-	if (sd)
-		update_shares(sd);
-
-	while (sd) {
-		struct sched_group *group;
-		int new_cpu, weight;
-
-		if (!(sd->flags & flag)) {
-			sd = sd->child;
-			continue;
-		}
-
-		group = find_idlest_group(sd, t, cpu);
-		if (!group) {
-			sd = sd->child;
-			continue;
-		}
-
-		new_cpu = find_idlest_cpu(group, t, cpu);
-		if (new_cpu == -1 || new_cpu == cpu) {
-			/* Now try balancing at a lower domain level of cpu */
-			sd = sd->child;
-			continue;
-		}
-
-		/* Now try balancing at a lower domain level of new_cpu */
-		cpu = new_cpu;
-		weight = cpumask_weight(sched_domain_span(sd));
-		sd = NULL;
-		for_each_domain(cpu, tmp) {
-			if (weight <= cpumask_weight(sched_domain_span(tmp)))
-				break;
-			if (tmp->flags & flag)
-				sd = tmp;
-		}
-		/* while loop will break here if sd == NULL */
-	}
-
-	return cpu;
-}
-
 #endif /* CONFIG_SMP */
 
 /**
@@ -2412,37 +2306,22 @@ void task_oncpu_function_call(struct task_struct *p,
  *
  * returns failure only if the task is already active.
  */
-static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
+static int try_to_wake_up(struct task_struct *p, unsigned int state,
+			  int wake_flags)
 {
 	int cpu, orig_cpu, this_cpu, success = 0;
 	unsigned long flags;
-	long old_state;
 	struct rq *rq;
 
 	if (!sched_feat(SYNC_WAKEUPS))
-		sync = 0;
-
-#ifdef CONFIG_SMP
-	if (sched_feat(LB_WAKEUP_UPDATE) && !root_task_group_empty()) {
-		struct sched_domain *sd;
+		wake_flags &= ~WF_SYNC;
 
-		this_cpu = raw_smp_processor_id();
-		cpu = task_cpu(p);
-
-		for_each_domain(this_cpu, sd) {
-			if (cpumask_test_cpu(cpu, sched_domain_span(sd))) {
-				update_shares(sd);
-				break;
-			}
-		}
-	}
-#endif
+	this_cpu = get_cpu();
 
 	smp_wmb();
 	rq = task_rq_lock(p, &flags);
 	update_rq_clock(rq);
-	old_state = p->state;
-	if (!(old_state & state))
+	if (!(p->state & state))
 		goto out;
 
 	if (p->se.on_rq)
@@ -2450,27 +2329,29 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
 
 	cpu = task_cpu(p);
 	orig_cpu = cpu;
-	this_cpu = smp_processor_id();
 
 #ifdef CONFIG_SMP
 	if (unlikely(task_running(rq, p)))
 		goto out_activate;
 
-	cpu = p->sched_class->select_task_rq(p, sync);
-	if (cpu != orig_cpu) {
+	/*
+	 * In order to handle concurrent wakeups and release the rq->lock
+	 * we put the task in TASK_WAKING state.
+	 *
+	 * First fix up the nr_uninterruptible count:
+	 */
+	if (task_contributes_to_load(p))
+		rq->nr_uninterruptible--;
+	p->state = TASK_WAKING;
+	task_rq_unlock(rq, &flags);
+
+	cpu = p->sched_class->select_task_rq(p, SD_BALANCE_WAKE, wake_flags);
+	if (cpu != orig_cpu)
 		set_task_cpu(p, cpu);
-		task_rq_unlock(rq, &flags);
-		/* might preempt at this point */
-		rq = task_rq_lock(p, &flags);
-		old_state = p->state;
-		if (!(old_state & state))
-			goto out;
-		if (p->se.on_rq)
-			goto out_running;
 
-		this_cpu = smp_processor_id();
-		cpu = task_cpu(p);
-	}
+	rq = task_rq_lock(p, &flags);
+	WARN_ON(p->state != TASK_WAKING);
+	cpu = task_cpu(p);
 
 #ifdef CONFIG_SCHEDSTATS
 	schedstat_inc(rq, ttwu_count);
@@ -2490,7 +2371,7 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
 out_activate:
 #endif /* CONFIG_SMP */
 	schedstat_inc(p, se.nr_wakeups);
-	if (sync)
+	if (wake_flags & WF_SYNC)
 		schedstat_inc(p, se.nr_wakeups_sync);
 	if (orig_cpu != cpu)
 		schedstat_inc(p, se.nr_wakeups_migrate);
@@ -2519,7 +2400,7 @@ out_activate:
 
 out_running:
 	trace_sched_wakeup(rq, p, success);
-	check_preempt_curr(rq, p, sync);
+	check_preempt_curr(rq, p, wake_flags);
 
 	p->state = TASK_RUNNING;
 #ifdef CONFIG_SMP
@@ -2528,6 +2409,7 @@ out_running:
 #endif
 out:
 	task_rq_unlock(rq, &flags);
+	put_cpu();
 
 	return success;
 }
@@ -2570,6 +2452,7 @@ static void __sched_fork(struct task_struct *p)
 	p->se.avg_overlap		= 0;
 	p->se.start_runtime		= 0;
 	p->se.avg_wakeup		= sysctl_sched_wakeup_granularity;
+	p->se.avg_running		= 0;
 
 #ifdef CONFIG_SCHEDSTATS
 	p->se.wait_start			= 0;
@@ -2631,18 +2514,41 @@ void sched_fork(struct task_struct *p, int clone_flags)
 
 	__sched_fork(p);
 
-#ifdef CONFIG_SMP
-	cpu = sched_balance_self(cpu, SD_BALANCE_FORK);
-#endif
-	set_task_cpu(p, cpu);
-
 	/*
-	 * Make sure we do not leak PI boosting priority to the child:
+	 * Make sure we do not leak PI boosting priority to the child.
 	 */
 	p->prio = current->normal_prio;
+
+	/*
+	 * Revert to default priority/policy on fork if requested.
+	 */
+	if (unlikely(p->sched_reset_on_fork)) {
+		if (p->policy == SCHED_FIFO || p->policy == SCHED_RR)
+			p->policy = SCHED_NORMAL;
+
+		if (p->normal_prio < DEFAULT_PRIO)
+			p->prio = DEFAULT_PRIO;
+
+		if (PRIO_TO_NICE(p->static_prio) < 0) {
+			p->static_prio = NICE_TO_PRIO(0);
+			set_load_weight(p);
+		}
+
+		/*
+		 * We don't need the reset flag anymore after the fork. It has
+		 * fulfilled its duty:
+		 */
+		p->sched_reset_on_fork = 0;
+	}
+
 	if (!rt_prio(p->prio))
 		p->sched_class = &fair_sched_class;
 
+#ifdef CONFIG_SMP
+	cpu = p->sched_class->select_task_rq(p, SD_BALANCE_FORK, 0);
+#endif
+	set_task_cpu(p, cpu);
+
 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
 	if (likely(sched_info_on()))
 		memset(&p->sched_info, 0, sizeof(p->sched_info));
@@ -2688,7 +2594,7 @@ void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
 		inc_nr_running(rq);
 	}
 	trace_sched_wakeup_new(rq, p, 1);
-	check_preempt_curr(rq, p, 0);
+	check_preempt_curr(rq, p, WF_FORK);
 #ifdef CONFIG_SMP
 	if (p->sched_class->task_wake_up)
 		p->sched_class->task_wake_up(rq, p);
@@ -2796,12 +2702,6 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
 {
 	struct mm_struct *mm = rq->prev_mm;
 	long prev_state;
-#ifdef CONFIG_SMP
-	int post_schedule = 0;
-
-	if (current->sched_class->needs_post_schedule)
-		post_schedule = current->sched_class->needs_post_schedule(rq);
-#endif
 
 	rq->prev_mm = NULL;
 
@@ -2818,12 +2718,8 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
 	 */
 	prev_state = prev->state;
 	finish_arch_switch(prev);
-	perf_counter_task_sched_in(current, cpu_of(rq));
+	perf_event_task_sched_in(current, cpu_of(rq));
 	finish_lock_switch(rq, prev);
-#ifdef CONFIG_SMP
-	if (post_schedule)
-		current->sched_class->post_schedule(rq);
-#endif
 
 	fire_sched_in_preempt_notifiers(current);
 	if (mm)
@@ -2838,6 +2734,42 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
 	}
 }
 
+#ifdef CONFIG_SMP
+
+/* assumes rq->lock is held */
+static inline void pre_schedule(struct rq *rq, struct task_struct *prev)
+{
+	if (prev->sched_class->pre_schedule)
+		prev->sched_class->pre_schedule(rq, prev);
+}
+
+/* rq->lock is NOT held, but preemption is disabled */
+static inline void post_schedule(struct rq *rq)
+{
+	if (rq->post_schedule) {
+		unsigned long flags;
+
+		spin_lock_irqsave(&rq->lock, flags);
+		if (rq->curr->sched_class->post_schedule)
+			rq->curr->sched_class->post_schedule(rq);
+		spin_unlock_irqrestore(&rq->lock, flags);
+
+		rq->post_schedule = 0;
+	}
+}
+
+#else
+
+static inline void pre_schedule(struct rq *rq, struct task_struct *p)
+{
+}
+
+static inline void post_schedule(struct rq *rq)
+{
+}
+
+#endif
+
 /**
  * schedule_tail - first thing a freshly forked thread must call.
  * @prev: the thread we just switched away from.
@@ -2848,6 +2780,13 @@ asmlinkage void schedule_tail(struct task_struct *prev)
 	struct rq *rq = this_rq();
 
 	finish_task_switch(rq, prev);
+
+	/*
+	 * FIXME: do we need to worry about rq being invalidated by the
+	 * task_switch?
+	 */
+	post_schedule(rq);
+
 #ifdef __ARCH_WANT_UNLOCKED_CTXSW
 	/* In this case, finish_task_switch does not reenable preemption */
 	preempt_enable();
@@ -2965,6 +2904,19 @@ unsigned long nr_iowait(void)
 	return sum;
 }
 
+unsigned long nr_iowait_cpu(void)
+{
+	struct rq *this = this_rq();
+	return atomic_read(&this->nr_iowait);
+}
+
+unsigned long this_cpu_load(void)
+{
+	struct rq *this = this_rq();
+	return this->cpu_load[0];
+}
+
+
 /* Variables and functions for calc_load */
 static atomic_long_t calc_load_tasks;
 static unsigned long calc_load_update;
@@ -3164,7 +3116,7 @@ out:
 void sched_exec(void)
 {
 	int new_cpu, this_cpu = get_cpu();
-	new_cpu = sched_balance_self(this_cpu, SD_BALANCE_EXEC);
+	new_cpu = current->sched_class->select_task_rq(current, SD_BALANCE_EXEC, 0);
 	put_cpu();
 	if (new_cpu != this_cpu)
 		sched_migrate_task(current, new_cpu);
@@ -3379,9 +3331,10 @@ static int move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest,
 {
 	const struct sched_class *class;
 
-	for (class = sched_class_highest; class; class = class->next)
+	for_each_class(class) {
 		if (class->move_one_task(this_rq, this_cpu, busiest, sd, idle))
 			return 1;
+	}
 
 	return 0;
 }
@@ -3544,7 +3497,7 @@ static inline void update_sd_power_savings_stats(struct sched_group *group,
 	 * capacity but still has some space to pick up some load
 	 * from other group and save more power
 	 */
-	if (sgs->sum_nr_running > sgs->group_capacity - 1)
+	if (sgs->sum_nr_running + 1 > sgs->group_capacity)
 		return;
 
 	if (sgs->sum_nr_running > sds->leader_nr_running ||
@@ -3583,11 +3536,6 @@ static inline int check_power_save_busiest_group(struct sd_lb_stats *sds,
 	*imbalance = sds->min_load_per_task;
 	sds->busiest = sds->group_min;
 
-	if (sched_mc_power_savings >= POWERSAVINGS_BALANCE_WAKEUP) {
-		cpu_rq(this_cpu)->rd->sched_mc_preferred_wakeup_cpu =
-			group_first_cpu(sds->group_leader);
-	}
-
 	return 1;
 
 }
@@ -3612,6 +3560,102 @@ static inline int check_power_save_busiest_group(struct sd_lb_stats *sds,
 #endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */
 
 
+unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu)
+{
+	return SCHED_LOAD_SCALE;
+}
+
+unsigned long __weak arch_scale_freq_power(struct sched_domain *sd, int cpu)
+{
+	return default_scale_freq_power(sd, cpu);
+}
+
+unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu)
+{
+	unsigned long weight = cpumask_weight(sched_domain_span(sd));
+	unsigned long smt_gain = sd->smt_gain;
+
+	smt_gain /= weight;
+
+	return smt_gain;
+}
+
+unsigned long __weak arch_scale_smt_power(struct sched_domain *sd, int cpu)
+{
+	return default_scale_smt_power(sd, cpu);
+}
+
+unsigned long scale_rt_power(int cpu)
+{
+	struct rq *rq = cpu_rq(cpu);
+	u64 total, available;
+
+	sched_avg_update(rq);
+
+	total = sched_avg_period() + (rq->clock - rq->age_stamp);
+	available = total - rq->rt_avg;
+
+	if (unlikely((s64)total < SCHED_LOAD_SCALE))
+		total = SCHED_LOAD_SCALE;
+
+	total >>= SCHED_LOAD_SHIFT;
+
+	return div_u64(available, total);
+}
+
+static void update_cpu_power(struct sched_domain *sd, int cpu)
+{
+	unsigned long weight = cpumask_weight(sched_domain_span(sd));
+	unsigned long power = SCHED_LOAD_SCALE;
+	struct sched_group *sdg = sd->groups;
+
+	if (sched_feat(ARCH_POWER))
+		power *= arch_scale_freq_power(sd, cpu);
+	else
+		power *= default_scale_freq_power(sd, cpu);
+
+	power >>= SCHED_LOAD_SHIFT;
+
+	if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) {
+		if (sched_feat(ARCH_POWER))
+			power *= arch_scale_smt_power(sd, cpu);
+		else
+			power *= default_scale_smt_power(sd, cpu);
+
+		power >>= SCHED_LOAD_SHIFT;
+	}
+
+	power *= scale_rt_power(cpu);
+	power >>= SCHED_LOAD_SHIFT;
+
+	if (!power)
+		power = 1;
+
+	sdg->cpu_power = power;
+}
+
+static void update_group_power(struct sched_domain *sd, int cpu)
+{
+	struct sched_domain *child = sd->child;
+	struct sched_group *group, *sdg = sd->groups;
+	unsigned long power;
+
+	if (!child) {
+		update_cpu_power(sd, cpu);
+		return;
+	}
+
+	power = 0;
+
+	group = child->groups;
+	do {
+		power += group->cpu_power;
+		group = group->next;
+	} while (group != child->groups);
+
+	sdg->cpu_power = power;
+}
+
 /**
  * update_sg_lb_stats - Update sched_group's statistics for load balancing.
  * @group: sched_group whose statistics are to be updated.
@@ -3624,7 +3668,8 @@ static inline int check_power_save_busiest_group(struct sd_lb_stats *sds,
  * @balance: Should we balance.
  * @sgs: variable to hold the statistics for this group.
  */
-static inline void update_sg_lb_stats(struct sched_group *group, int this_cpu,
+static inline void update_sg_lb_stats(struct sched_domain *sd,
+			struct sched_group *group, int this_cpu,
 			enum cpu_idle_type idle, int load_idx, int *sd_idle,
 			int local_group, const struct cpumask *cpus,
 			int *balance, struct sg_lb_stats *sgs)
@@ -3635,8 +3680,11 @@ static inline void update_sg_lb_stats(struct sched_group *group, int this_cpu,
 	unsigned long sum_avg_load_per_task;
 	unsigned long avg_load_per_task;
 
-	if (local_group)
+	if (local_group) {
 		balance_cpu = group_first_cpu(group);
+		if (balance_cpu == this_cpu)
+			update_group_power(sd, this_cpu);
+	}
 
 	/* Tally up the load of all CPUs in the group */
 	sum_avg_load_per_task = avg_load_per_task = 0;
@@ -3685,8 +3733,7 @@ static inline void update_sg_lb_stats(struct sched_group *group, int this_cpu,
 	}
 
 	/* Adjust by relative CPU power of the group */
-	sgs->avg_load = sg_div_cpu_power(group,
-			sgs->group_load * SCHED_LOAD_SCALE);
+	sgs->avg_load = (sgs->group_load * SCHED_LOAD_SCALE) / group->cpu_power;
 
 
 	/*
@@ -3698,14 +3745,14 @@ static inline void update_sg_lb_stats(struct sched_group *group, int this_cpu,
 	 *      normalized nr_running number somewhere that negates
 	 *      the hierarchy?
 	 */
-	avg_load_per_task = sg_div_cpu_power(group,
-			sum_avg_load_per_task * SCHED_LOAD_SCALE);
+	avg_load_per_task = (sum_avg_load_per_task * SCHED_LOAD_SCALE) /
+		group->cpu_power;
 
 	if ((max_cpu_load - min_cpu_load) > 2*avg_load_per_task)
 		sgs->group_imb = 1;
 
-	sgs->group_capacity = group->__cpu_power / SCHED_LOAD_SCALE;
-
+	sgs->group_capacity =
+		DIV_ROUND_CLOSEST(group->cpu_power, SCHED_LOAD_SCALE);
 }
 
 /**
@@ -3723,9 +3770,13 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu,
 			const struct cpumask *cpus, int *balance,
 			struct sd_lb_stats *sds)
 {
+	struct sched_domain *child = sd->child;
 	struct sched_group *group = sd->groups;
 	struct sg_lb_stats sgs;
-	int load_idx;
+	int load_idx, prefer_sibling = 0;
+
+	if (child && child->flags & SD_PREFER_SIBLING)
+		prefer_sibling = 1;
 
 	init_sd_power_savings_stats(sd, sds, idle);
 	load_idx = get_sd_load_idx(sd, idle);
@@ -3736,14 +3787,22 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu,
 		local_group = cpumask_test_cpu(this_cpu,
 					       sched_group_cpus(group));
 		memset(&sgs, 0, sizeof(sgs));
-		update_sg_lb_stats(group, this_cpu, idle, load_idx, sd_idle,
+		update_sg_lb_stats(sd, group, this_cpu, idle, load_idx, sd_idle,
 				local_group, cpus, balance, &sgs);
 
 		if (local_group && balance && !(*balance))
 			return;
 
 		sds->total_load += sgs.group_load;
-		sds->total_pwr += group->__cpu_power;
+		sds->total_pwr += group->cpu_power;
+
+		/*
+		 * In case the child domain prefers tasks go to siblings
+		 * first, lower the group capacity to one so that we'll try
+		 * and move all the excess tasks away.
+		 */
+		if (prefer_sibling)
+			sgs.group_capacity = min(sgs.group_capacity, 1UL);
 
 		if (local_group) {
 			sds->this_load = sgs.avg_load;
@@ -3763,7 +3822,6 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu,
 		update_sd_power_savings_stats(group, sds, local_group, &sgs);
 		group = group->next;
 	} while (group != sd->groups);
-
 }
 
 /**
@@ -3801,28 +3859,28 @@ static inline void fix_small_imbalance(struct sd_lb_stats *sds,
 	 * moving them.
 	 */
 
-	pwr_now += sds->busiest->__cpu_power *
+	pwr_now += sds->busiest->cpu_power *
 			min(sds->busiest_load_per_task, sds->max_load);
-	pwr_now += sds->this->__cpu_power *
+	pwr_now += sds->this->cpu_power *
 			min(sds->this_load_per_task, sds->this_load);
 	pwr_now /= SCHED_LOAD_SCALE;
 
 	/* Amount of load we'd subtract */
-	tmp = sg_div_cpu_power(sds->busiest,
-			sds->busiest_load_per_task * SCHED_LOAD_SCALE);
+	tmp = (sds->busiest_load_per_task * SCHED_LOAD_SCALE) /
+		sds->busiest->cpu_power;
 	if (sds->max_load > tmp)
-		pwr_move += sds->busiest->__cpu_power *
+		pwr_move += sds->busiest->cpu_power *
 			min(sds->busiest_load_per_task, sds->max_load - tmp);
 
 	/* Amount of load we'd add */
-	if (sds->max_load * sds->busiest->__cpu_power <
+	if (sds->max_load * sds->busiest->cpu_power <
 		sds->busiest_load_per_task * SCHED_LOAD_SCALE)
-		tmp = sg_div_cpu_power(sds->this,
-			sds->max_load * sds->busiest->__cpu_power);
+		tmp = (sds->max_load * sds->busiest->cpu_power) /
+			sds->this->cpu_power;
 	else
-		tmp = sg_div_cpu_power(sds->this,
-			sds->busiest_load_per_task * SCHED_LOAD_SCALE);
-	pwr_move += sds->this->__cpu_power *
+		tmp = (sds->busiest_load_per_task * SCHED_LOAD_SCALE) /
+			sds->this->cpu_power;
+	pwr_move += sds->this->cpu_power *
 			min(sds->this_load_per_task, sds->this_load + tmp);
 	pwr_move /= SCHED_LOAD_SCALE;
 
@@ -3857,8 +3915,8 @@ static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu,
 			sds->max_load - sds->busiest_load_per_task);
 
 	/* How much load to actually move to equalise the imbalance */
-	*imbalance = min(max_pull * sds->busiest->__cpu_power,
-		(sds->avg_load - sds->this_load) * sds->this->__cpu_power)
+	*imbalance = min(max_pull * sds->busiest->cpu_power,
+		(sds->avg_load - sds->this_load) * sds->this->cpu_power)
 			/ SCHED_LOAD_SCALE;
 
 	/*
@@ -3988,15 +4046,18 @@ find_busiest_queue(struct sched_group *group, enum cpu_idle_type idle,
 	int i;
 
 	for_each_cpu(i, sched_group_cpus(group)) {
+		unsigned long power = power_of(i);
+		unsigned long capacity = DIV_ROUND_CLOSEST(power, SCHED_LOAD_SCALE);
 		unsigned long wl;
 
 		if (!cpumask_test_cpu(i, cpus))
 			continue;
 
 		rq = cpu_rq(i);
-		wl = weighted_cpuload(i);
+		wl = weighted_cpuload(i) * SCHED_LOAD_SCALE;
+		wl /= power;
 
-		if (rq->nr_running == 1 && wl > imbalance)
+		if (capacity && rq->nr_running == 1 && wl > imbalance)
 			continue;
 
 		if (wl > max_load) {
@@ -5031,17 +5092,16 @@ void account_idle_time(cputime_t cputime)
  */
 void account_process_tick(struct task_struct *p, int user_tick)
 {
-	cputime_t one_jiffy = jiffies_to_cputime(1);
-	cputime_t one_jiffy_scaled = cputime_to_scaled(one_jiffy);
+	cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy);
 	struct rq *rq = this_rq();
 
 	if (user_tick)
-		account_user_time(p, one_jiffy, one_jiffy_scaled);
+		account_user_time(p, cputime_one_jiffy, one_jiffy_scaled);
 	else if ((p != rq->idle) || (irq_count() != HARDIRQ_OFFSET))
-		account_system_time(p, HARDIRQ_OFFSET, one_jiffy,
+		account_system_time(p, HARDIRQ_OFFSET, cputime_one_jiffy,
 				    one_jiffy_scaled);
 	else
-		account_idle_time(one_jiffy);
+		account_idle_time(cputime_one_jiffy);
 }
 
 /*
@@ -5145,7 +5205,7 @@ void scheduler_tick(void)
 	curr->sched_class->task_tick(rq, curr, 0);
 	spin_unlock(&rq->lock);
 
-	perf_counter_task_tick(curr, cpu);
+	perf_event_task_tick(curr, cpu);
 
 #ifdef CONFIG_SMP
 	rq->idle_at_tick = idle_cpu(cpu);
@@ -5257,14 +5317,13 @@ static inline void schedule_debug(struct task_struct *prev)
 #endif
 }
 
-static void put_prev_task(struct rq *rq, struct task_struct *prev)
+static void put_prev_task(struct rq *rq, struct task_struct *p)
 {
-	if (prev->state == TASK_RUNNING) {
-		u64 runtime = prev->se.sum_exec_runtime;
+	u64 runtime = p->se.sum_exec_runtime - p->se.prev_sum_exec_runtime;
 
-		runtime -= prev->se.prev_sum_exec_runtime;
-		runtime = min_t(u64, runtime, 2*sysctl_sched_migration_cost);
+	update_avg(&p->se.avg_running, runtime);
 
+	if (p->state == TASK_RUNNING) {
 		/*
 		 * In order to avoid avg_overlap growing stale when we are
 		 * indeed overlapping and hence not getting put to sleep, grow
@@ -5274,9 +5333,12 @@ static void put_prev_task(struct rq *rq, struct task_struct *prev)
 		 * correlates to the amount of cache footprint a task can
 		 * build up.
 		 */
-		update_avg(&prev->se.avg_overlap, runtime);
+		runtime = min_t(u64, runtime, 2*sysctl_sched_migration_cost);
+		update_avg(&p->se.avg_overlap, runtime);
+	} else {
+		update_avg(&p->se.avg_running, 0);
 	}
-	prev->sched_class->put_prev_task(rq, prev);
+	p->sched_class->put_prev_task(rq, p);
 }
 
 /*
@@ -5325,7 +5387,7 @@ need_resched:
 	preempt_disable();
 	cpu = smp_processor_id();
 	rq = cpu_rq(cpu);
-	rcu_qsctr_inc(cpu);
+	rcu_sched_qs(cpu);
 	prev = rq->curr;
 	switch_count = &prev->nivcsw;
 
@@ -5349,10 +5411,7 @@ need_resched_nonpreemptible:
 		switch_count = &prev->nvcsw;
 	}
 
-#ifdef CONFIG_SMP
-	if (prev->sched_class->pre_schedule)
-		prev->sched_class->pre_schedule(rq, prev);
-#endif
+	pre_schedule(rq, prev);
 
 	if (unlikely(!rq->nr_running))
 		idle_balance(cpu, rq);
@@ -5362,7 +5421,7 @@ need_resched_nonpreemptible:
 
 	if (likely(prev != next)) {
 		sched_info_switch(prev, next);
-		perf_counter_task_sched_out(prev, next, cpu);
+		perf_event_task_sched_out(prev, next, cpu);
 
 		rq->nr_switches++;
 		rq->curr = next;
@@ -5378,6 +5437,8 @@ need_resched_nonpreemptible:
 	} else
 		spin_unlock_irq(&rq->lock);
 
+	post_schedule(rq);
+
 	if (unlikely(reacquire_kernel_lock(current) < 0))
 		goto need_resched_nonpreemptible;
 
@@ -5509,10 +5570,10 @@ asmlinkage void __sched preempt_schedule_irq(void)
 
 #endif /* CONFIG_PREEMPT */
 
-int default_wake_function(wait_queue_t *curr, unsigned mode, int sync,
+int default_wake_function(wait_queue_t *curr, unsigned mode, int wake_flags,
 			  void *key)
 {
-	return try_to_wake_up(curr->private, mode, sync);
+	return try_to_wake_up(curr->private, mode, wake_flags);
 }
 EXPORT_SYMBOL(default_wake_function);
 
@@ -5526,14 +5587,14 @@ EXPORT_SYMBOL(default_wake_function);
  * zero in this (rare) case, and we handle it by continuing to scan the queue.
  */
 static void __wake_up_common(wait_queue_head_t *q, unsigned int mode,
-			int nr_exclusive, int sync, void *key)
+			int nr_exclusive, int wake_flags, void *key)
 {
 	wait_queue_t *curr, *next;
 
 	list_for_each_entry_safe(curr, next, &q->task_list, task_list) {
 		unsigned flags = curr->flags;
 
-		if (curr->func(curr, mode, sync, key) &&
+		if (curr->func(curr, mode, wake_flags, key) &&
 				(flags & WQ_FLAG_EXCLUSIVE) && !--nr_exclusive)
 			break;
 	}
@@ -5594,16 +5655,16 @@ void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode,
 			int nr_exclusive, void *key)
 {
 	unsigned long flags;
-	int sync = 1;
+	int wake_flags = WF_SYNC;
 
 	if (unlikely(!q))
 		return;
 
 	if (unlikely(!nr_exclusive))
-		sync = 0;
+		wake_flags = 0;
 
 	spin_lock_irqsave(&q->lock, flags);
-	__wake_up_common(q, mode, nr_exclusive, sync, key);
+	__wake_up_common(q, mode, nr_exclusive, wake_flags, key);
 	spin_unlock_irqrestore(&q->lock, flags);
 }
 EXPORT_SYMBOL_GPL(__wake_up_sync_key);
@@ -6123,17 +6184,25 @@ static int __sched_setscheduler(struct task_struct *p, int policy,
 	unsigned long flags;
 	const struct sched_class *prev_class = p->sched_class;
 	struct rq *rq;
+	int reset_on_fork;
 
 	/* may grab non-irq protected spin_locks */
 	BUG_ON(in_interrupt());
 recheck:
 	/* double check policy once rq lock held */
-	if (policy < 0)
+	if (policy < 0) {
+		reset_on_fork = p->sched_reset_on_fork;
 		policy = oldpolicy = p->policy;
-	else if (policy != SCHED_FIFO && policy != SCHED_RR &&
-			policy != SCHED_NORMAL && policy != SCHED_BATCH &&
-			policy != SCHED_IDLE)
-		return -EINVAL;
+	} else {
+		reset_on_fork = !!(policy & SCHED_RESET_ON_FORK);
+		policy &= ~SCHED_RESET_ON_FORK;
+
+		if (policy != SCHED_FIFO && policy != SCHED_RR &&
+				policy != SCHED_NORMAL && policy != SCHED_BATCH &&
+				policy != SCHED_IDLE)
+			return -EINVAL;
+	}
+
 	/*
 	 * Valid priorities for SCHED_FIFO and SCHED_RR are
 	 * 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL,
@@ -6177,6 +6246,10 @@ recheck:
 		/* can't change other user's priorities */
 		if (!check_same_owner(p))
 			return -EPERM;
+
+		/* Normal users shall not reset the sched_reset_on_fork flag */
+		if (p->sched_reset_on_fork && !reset_on_fork)
+			return -EPERM;
 	}
 
 	if (user) {
@@ -6220,6 +6293,8 @@ recheck:
 	if (running)
 		p->sched_class->put_prev_task(rq, p);
 
+	p->sched_reset_on_fork = reset_on_fork;
+
 	oldprio = p->prio;
 	__setscheduler(rq, p, policy, param->sched_priority);
 
@@ -6336,14 +6411,15 @@ SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid)
 	if (p) {
 		retval = security_task_getscheduler(p);
 		if (!retval)
-			retval = p->policy;
+			retval = p->policy
+				| (p->sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0);
 	}
 	read_unlock(&tasklist_lock);
 	return retval;
 }
 
 /**
- * sys_sched_getscheduler - get the RT priority of a thread
+ * sys_sched_getparam - get the RT priority of a thread
  * @pid: the pid in question.
  * @param: structure containing the RT priority.
  */
@@ -6571,19 +6647,9 @@ static inline int should_resched(void)
 
 static void __cond_resched(void)
 {
-#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
-	__might_sleep(__FILE__, __LINE__);
-#endif
-	/*
-	 * The BKS might be reacquired before we have dropped
-	 * PREEMPT_ACTIVE, which could trigger a second
-	 * cond_resched() call.
-	 */
-	do {
-		add_preempt_count(PREEMPT_ACTIVE);
-		schedule();
-		sub_preempt_count(PREEMPT_ACTIVE);
-	} while (need_resched());
+	add_preempt_count(PREEMPT_ACTIVE);
+	schedule();
+	sub_preempt_count(PREEMPT_ACTIVE);
 }
 
 int __sched _cond_resched(void)
@@ -6597,18 +6663,20 @@ int __sched _cond_resched(void)
 EXPORT_SYMBOL(_cond_resched);
 
 /*
- * cond_resched_lock() - if a reschedule is pending, drop the given lock,
+ * __cond_resched_lock() - if a reschedule is pending, drop the given lock,
  * call schedule, and on return reacquire the lock.
  *
  * This works OK both with and without CONFIG_PREEMPT. We do strange low-level
  * operations here to prevent schedule() from being called twice (once via
  * spin_unlock(), once by hand).
  */
-int cond_resched_lock(spinlock_t *lock)
+int __cond_resched_lock(spinlock_t *lock)
 {
 	int resched = should_resched();
 	int ret = 0;
 
+	lockdep_assert_held(lock);
+
 	if (spin_needbreak(lock) || resched) {
 		spin_unlock(lock);
 		if (resched)
@@ -6620,9 +6688,9 @@ int cond_resched_lock(spinlock_t *lock)
 	}
 	return ret;
 }
-EXPORT_SYMBOL(cond_resched_lock);
+EXPORT_SYMBOL(__cond_resched_lock);
 
-int __sched cond_resched_softirq(void)
+int __sched __cond_resched_softirq(void)
 {
 	BUG_ON(!in_softirq());
 
@@ -6634,7 +6702,7 @@ int __sched cond_resched_softirq(void)
 	}
 	return 0;
 }
-EXPORT_SYMBOL(cond_resched_softirq);
+EXPORT_SYMBOL(__cond_resched_softirq);
 
 /**
  * yield - yield the current processor to other threads.
@@ -6658,11 +6726,13 @@ EXPORT_SYMBOL(yield);
  */
 void __sched io_schedule(void)
 {
-	struct rq *rq = &__raw_get_cpu_var(runqueues);
+	struct rq *rq = raw_rq();
 
 	delayacct_blkio_start();
 	atomic_inc(&rq->nr_iowait);
+	current->in_iowait = 1;
 	schedule();
+	current->in_iowait = 0;
 	atomic_dec(&rq->nr_iowait);
 	delayacct_blkio_end();
 }
@@ -6670,12 +6740,14 @@ EXPORT_SYMBOL(io_schedule);
 
 long __sched io_schedule_timeout(long timeout)
 {
-	struct rq *rq = &__raw_get_cpu_var(runqueues);
+	struct rq *rq = raw_rq();
 	long ret;
 
 	delayacct_blkio_start();
 	atomic_inc(&rq->nr_iowait);
+	current->in_iowait = 1;
 	ret = schedule_timeout(timeout);
+	current->in_iowait = 0;
 	atomic_dec(&rq->nr_iowait);
 	delayacct_blkio_end();
 	return ret;
@@ -6759,23 +6831,8 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
 	if (retval)
 		goto out_unlock;
 
-	/*
-	 * Time slice is 0 for SCHED_FIFO tasks and for SCHED_OTHER
-	 * tasks that are on an otherwise idle runqueue:
-	 */
-	time_slice = 0;
-	if (p->policy == SCHED_RR) {
-		time_slice = DEF_TIMESLICE;
-	} else if (p->policy != SCHED_FIFO) {
-		struct sched_entity *se = &p->se;
-		unsigned long flags;
-		struct rq *rq;
+	time_slice = p->sched_class->get_rr_interval(p);
 
-		rq = task_rq_lock(p, &flags);
-		if (rq->cfs.load.weight)
-			time_slice = NS_TO_JIFFIES(sched_slice(&rq->cfs, se));
-		task_rq_unlock(rq, &flags);
-	}
 	read_unlock(&tasklist_lock);
 	jiffies_to_timespec(time_slice, &t);
 	retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
@@ -6992,8 +7049,12 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
 
 	if (migrate_task(p, cpumask_any_and(cpu_online_mask, new_mask), &req)) {
 		/* Need help from migration thread: drop lock and wait. */
+		struct task_struct *mt = rq->migration_thread;
+
+		get_task_struct(mt);
 		task_rq_unlock(rq, &flags);
 		wake_up_process(rq->migration_thread);
+		put_task_struct(mt);
 		wait_for_completion(&req.done);
 		tlb_migrate_finish(p->mm);
 		return 0;
@@ -7051,6 +7112,11 @@ fail:
 	return ret;
 }
 
+#define RCU_MIGRATION_IDLE	0
+#define RCU_MIGRATION_NEED_QS	1
+#define RCU_MIGRATION_GOT_QS	2
+#define RCU_MIGRATION_MUST_SYNC	3
+
 /*
  * migration_thread - this is a highprio system thread that performs
  * thread migration by bumping thread off CPU then 'pushing' onto
@@ -7058,6 +7124,7 @@ fail:
  */
 static int migration_thread(void *data)
 {
+	int badcpu;
 	int cpu = (long)data;
 	struct rq *rq;
 
@@ -7092,8 +7159,17 @@ static int migration_thread(void *data)
 		req = list_entry(head->next, struct migration_req, list);
 		list_del_init(head->next);
 
-		spin_unlock(&rq->lock);
-		__migrate_task(req->task, cpu, req->dest_cpu);
+		if (req->task != NULL) {
+			spin_unlock(&rq->lock);
+			__migrate_task(req->task, cpu, req->dest_cpu);
+		} else if (likely(cpu == (badcpu = smp_processor_id()))) {
+			req->dest_cpu = RCU_MIGRATION_GOT_QS;
+			spin_unlock(&rq->lock);
+		} else {
+			req->dest_cpu = RCU_MIGRATION_MUST_SYNC;
+			spin_unlock(&rq->lock);
+			WARN_ONCE(1, "migration_thread() on CPU %d, expected %d\n", badcpu, cpu);
+		}
 		local_irq_enable();
 
 		complete(&req->done);
@@ -7607,7 +7683,7 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
 /*
  * Register at high priority so that task migration (migrate_all_tasks)
  * happens before everything else.  This has to be lower priority than
- * the notifier in the perf_counter subsystem, though.
+ * the notifier in the perf_event subsystem, though.
  */
 static struct notifier_block __cpuinitdata migration_notifier = {
 	.notifier_call = migration_call,
@@ -7625,7 +7701,7 @@ static int __init migration_init(void)
 	migration_call(&migration_notifier, CPU_ONLINE, cpu);
 	register_cpu_notifier(&migration_notifier);
 
-	return err;
+	return 0;
 }
 early_initcall(migration_init);
 #endif
@@ -7672,7 +7748,7 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
 			break;
 		}
 
-		if (!group->__cpu_power) {
+		if (!group->cpu_power) {
 			printk(KERN_CONT "\n");
 			printk(KERN_ERR "ERROR: domain->cpu_power not "
 					"set\n");
@@ -7696,9 +7772,9 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
 		cpulist_scnprintf(str, sizeof(str), sched_group_cpus(group));
 
 		printk(KERN_CONT " %s", str);
-		if (group->__cpu_power != SCHED_LOAD_SCALE) {
-			printk(KERN_CONT " (__cpu_power = %d)",
-				group->__cpu_power);
+		if (group->cpu_power != SCHED_LOAD_SCALE) {
+			printk(KERN_CONT " (cpu_power = %d)",
+				group->cpu_power);
 		}
 
 		group = group->next;
@@ -7763,9 +7839,7 @@ static int sd_degenerate(struct sched_domain *sd)
 	}
 
 	/* Following flags don't use groups */
-	if (sd->flags & (SD_WAKE_IDLE |
-			 SD_WAKE_AFFINE |
-			 SD_WAKE_BALANCE))
+	if (sd->flags & (SD_WAKE_AFFINE))
 		return 0;
 
 	return 1;
@@ -7782,10 +7856,6 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
 	if (!cpumask_equal(sched_domain_span(sd), sched_domain_span(parent)))
 		return 0;
 
-	/* Does parent contain flags not in child? */
-	/* WAKE_BALANCE is a subset of WAKE_AFFINE */
-	if (cflags & SD_WAKE_AFFINE)
-		pflags &= ~SD_WAKE_BALANCE;
 	/* Flags needing groups don't count if only 1 group in parent */
 	if (parent->groups == parent->groups->next) {
 		pflags &= ~(SD_LOAD_BALANCE |
@@ -7841,7 +7911,7 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd)
 	rq->rd = rd;
 
 	cpumask_set_cpu(rq->cpu, rd->span);
-	if (cpumask_test_cpu(rq->cpu, cpu_online_mask))
+	if (cpumask_test_cpu(rq->cpu, cpu_active_mask))
 		set_rq_online(rq);
 
 	spin_unlock_irqrestore(&rq->lock, flags);
@@ -7983,7 +8053,7 @@ init_sched_build_groups(const struct cpumask *span,
 			continue;
 
 		cpumask_clear(sched_group_cpus(sg));
-		sg->__cpu_power = 0;
+		sg->cpu_power = 0;
 
 		for_each_cpu(j, span) {
 			if (group_fn(j, cpu_map, NULL, tmpmask) != group)
@@ -8091,6 +8161,39 @@ struct static_sched_domain {
 	DECLARE_BITMAP(span, CONFIG_NR_CPUS);
 };
 
+struct s_data {
+#ifdef CONFIG_NUMA
+	int			sd_allnodes;
+	cpumask_var_t		domainspan;
+	cpumask_var_t		covered;
+	cpumask_var_t		notcovered;
+#endif
+	cpumask_var_t		nodemask;
+	cpumask_var_t		this_sibling_map;
+	cpumask_var_t		this_core_map;
+	cpumask_var_t		send_covered;
+	cpumask_var_t		tmpmask;
+	struct sched_group	**sched_group_nodes;
+	struct root_domain	*rd;
+};
+
+enum s_alloc {
+	sa_sched_groups = 0,
+	sa_rootdomain,
+	sa_tmpmask,
+	sa_send_covered,
+	sa_this_core_map,
+	sa_this_sibling_map,
+	sa_nodemask,
+	sa_sched_group_nodes,
+#ifdef CONFIG_NUMA
+	sa_notcovered,
+	sa_covered,
+	sa_domainspan,
+#endif
+	sa_none,
+};
+
 /*
  * SMT sched-domains:
  */
@@ -8208,11 +8311,76 @@ static void init_numa_sched_groups_power(struct sched_group *group_head)
 				continue;
 			}
 
-			sg_inc_cpu_power(sg, sd->groups->__cpu_power);
+			sg->cpu_power += sd->groups->cpu_power;
 		}
 		sg = sg->next;
 	} while (sg != group_head);
 }
+
+static int build_numa_sched_groups(struct s_data *d,
+				   const struct cpumask *cpu_map, int num)
+{
+	struct sched_domain *sd;
+	struct sched_group *sg, *prev;
+	int n, j;
+
+	cpumask_clear(d->covered);
+	cpumask_and(d->nodemask, cpumask_of_node(num), cpu_map);
+	if (cpumask_empty(d->nodemask)) {
+		d->sched_group_nodes[num] = NULL;
+		goto out;
+	}
+
+	sched_domain_node_span(num, d->domainspan);
+	cpumask_and(d->domainspan, d->domainspan, cpu_map);
+
+	sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(),
+			  GFP_KERNEL, num);
+	if (!sg) {
+		printk(KERN_WARNING "Can not alloc domain group for node %d\n",
+		       num);
+		return -ENOMEM;
+	}
+	d->sched_group_nodes[num] = sg;
+
+	for_each_cpu(j, d->nodemask) {
+		sd = &per_cpu(node_domains, j).sd;
+		sd->groups = sg;
+	}
+
+	sg->cpu_power = 0;
+	cpumask_copy(sched_group_cpus(sg), d->nodemask);
+	sg->next = sg;
+	cpumask_or(d->covered, d->covered, d->nodemask);
+
+	prev = sg;
+	for (j = 0; j < nr_node_ids; j++) {
+		n = (num + j) % nr_node_ids;
+		cpumask_complement(d->notcovered, d->covered);
+		cpumask_and(d->tmpmask, d->notcovered, cpu_map);
+		cpumask_and(d->tmpmask, d->tmpmask, d->domainspan);
+		if (cpumask_empty(d->tmpmask))
+			break;
+		cpumask_and(d->tmpmask, d->tmpmask, cpumask_of_node(n));
+		if (cpumask_empty(d->tmpmask))
+			continue;
+		sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(),
+				  GFP_KERNEL, num);
+		if (!sg) {
+			printk(KERN_WARNING
+			       "Can not alloc domain group for node %d\n", j);
+			return -ENOMEM;
+		}
+		sg->cpu_power = 0;
+		cpumask_copy(sched_group_cpus(sg), d->tmpmask);
+		sg->next = prev->next;
+		cpumask_or(d->covered, d->covered, d->tmpmask);
+		prev->next = sg;
+		prev = sg;
+	}
+out:
+	return 0;
+}
 #endif /* CONFIG_NUMA */
 
 #ifdef CONFIG_NUMA
@@ -8266,15 +8434,13 @@ static void free_sched_groups(const struct cpumask *cpu_map,
  * there are asymmetries in the topology. If there are asymmetries, group
  * having more cpu_power will pickup more load compared to the group having
  * less cpu_power.
- *
- * cpu_power will be a multiple of SCHED_LOAD_SCALE. This multiple represents
- * the maximum number of tasks a group can handle in the presence of other idle
- * or lightly loaded groups in the same sched domain.
  */
 static void init_sched_groups_power(int cpu, struct sched_domain *sd)
 {
 	struct sched_domain *child;
 	struct sched_group *group;
+	long power;
+	int weight;
 
 	WARN_ON(!sd || !sd->groups);
 
@@ -8283,28 +8449,32 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd)
 
 	child = sd->child;
 
-	sd->groups->__cpu_power = 0;
+	sd->groups->cpu_power = 0;
 
-	/*
-	 * For perf policy, if the groups in child domain share resources
-	 * (for example cores sharing some portions of the cache hierarchy
-	 * or SMT), then set this domain groups cpu_power such that each group
-	 * can handle only one task, when there are other idle groups in the
-	 * same sched domain.
-	 */
-	if (!child || (!(sd->flags & SD_POWERSAVINGS_BALANCE) &&
-		       (child->flags &
-			(SD_SHARE_CPUPOWER | SD_SHARE_PKG_RESOURCES)))) {
-		sg_inc_cpu_power(sd->groups, SCHED_LOAD_SCALE);
+	if (!child) {
+		power = SCHED_LOAD_SCALE;
+		weight = cpumask_weight(sched_domain_span(sd));
+		/*
+		 * SMT siblings share the power of a single core.
+		 * Usually multiple threads get a better yield out of
+		 * that one core than a single thread would have,
+		 * reflect that in sd->smt_gain.
+		 */
+		if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) {
+			power *= sd->smt_gain;
+			power /= weight;
+			power >>= SCHED_LOAD_SHIFT;
+		}
+		sd->groups->cpu_power += power;
 		return;
 	}
 
 	/*
-	 * add cpu_power of each child group to this groups cpu_power
+	 * Add cpu_power of each child group to this groups cpu_power.
 	 */
 	group = child->groups;
 	do {
-		sg_inc_cpu_power(sd->groups, group->__cpu_power);
+		sd->groups->cpu_power += group->cpu_power;
 		group = group->next;
 	} while (group != child->groups);
 }
@@ -8371,287 +8541,292 @@ static void set_domain_attribute(struct sched_domain *sd,
 		request = attr->relax_domain_level;
 	if (request < sd->level) {
 		/* turn off idle balance on this domain */
-		sd->flags &= ~(SD_WAKE_IDLE|SD_BALANCE_NEWIDLE);
+		sd->flags &= ~(SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE);
 	} else {
 		/* turn on idle balance on this domain */
-		sd->flags |= (SD_WAKE_IDLE_FAR|SD_BALANCE_NEWIDLE);
+		sd->flags |= (SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE);
+	}
+}
+
+static void __free_domain_allocs(struct s_data *d, enum s_alloc what,
+				 const struct cpumask *cpu_map)
+{
+	switch (what) {
+	case sa_sched_groups:
+		free_sched_groups(cpu_map, d->tmpmask); /* fall through */
+		d->sched_group_nodes = NULL;
+	case sa_rootdomain:
+		free_rootdomain(d->rd); /* fall through */
+	case sa_tmpmask:
+		free_cpumask_var(d->tmpmask); /* fall through */
+	case sa_send_covered:
+		free_cpumask_var(d->send_covered); /* fall through */
+	case sa_this_core_map:
+		free_cpumask_var(d->this_core_map); /* fall through */
+	case sa_this_sibling_map:
+		free_cpumask_var(d->this_sibling_map); /* fall through */
+	case sa_nodemask:
+		free_cpumask_var(d->nodemask); /* fall through */
+	case sa_sched_group_nodes:
+#ifdef CONFIG_NUMA
+		kfree(d->sched_group_nodes); /* fall through */
+	case sa_notcovered:
+		free_cpumask_var(d->notcovered); /* fall through */
+	case sa_covered:
+		free_cpumask_var(d->covered); /* fall through */
+	case sa_domainspan:
+		free_cpumask_var(d->domainspan); /* fall through */
+#endif
+	case sa_none:
+		break;
 	}
 }
 
-/*
- * Build sched domains for a given set of cpus and attach the sched domains
- * to the individual cpus
- */
-static int __build_sched_domains(const struct cpumask *cpu_map,
-				 struct sched_domain_attr *attr)
+static enum s_alloc __visit_domain_allocation_hell(struct s_data *d,
+						   const struct cpumask *cpu_map)
 {
-	int i, err = -ENOMEM;
-	struct root_domain *rd;
-	cpumask_var_t nodemask, this_sibling_map, this_core_map, send_covered,
-		tmpmask;
 #ifdef CONFIG_NUMA
-	cpumask_var_t domainspan, covered, notcovered;
-	struct sched_group **sched_group_nodes = NULL;
-	int sd_allnodes = 0;
-
-	if (!alloc_cpumask_var(&domainspan, GFP_KERNEL))
-		goto out;
-	if (!alloc_cpumask_var(&covered, GFP_KERNEL))
-		goto free_domainspan;
-	if (!alloc_cpumask_var(&notcovered, GFP_KERNEL))
-		goto free_covered;
-#endif
-
-	if (!alloc_cpumask_var(&nodemask, GFP_KERNEL))
-		goto free_notcovered;
-	if (!alloc_cpumask_var(&this_sibling_map, GFP_KERNEL))
-		goto free_nodemask;
-	if (!alloc_cpumask_var(&this_core_map, GFP_KERNEL))
-		goto free_this_sibling_map;
-	if (!alloc_cpumask_var(&send_covered, GFP_KERNEL))
-		goto free_this_core_map;
-	if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
-		goto free_send_covered;
-
-#ifdef CONFIG_NUMA
-	/*
-	 * Allocate the per-node list of sched groups
-	 */
-	sched_group_nodes = kcalloc(nr_node_ids, sizeof(struct sched_group *),
-				    GFP_KERNEL);
-	if (!sched_group_nodes) {
+	if (!alloc_cpumask_var(&d->domainspan, GFP_KERNEL))
+		return sa_none;
+	if (!alloc_cpumask_var(&d->covered, GFP_KERNEL))
+		return sa_domainspan;
+	if (!alloc_cpumask_var(&d->notcovered, GFP_KERNEL))
+		return sa_covered;
+	/* Allocate the per-node list of sched groups */
+	d->sched_group_nodes = kcalloc(nr_node_ids,
+				      sizeof(struct sched_group *), GFP_KERNEL);
+	if (!d->sched_group_nodes) {
 		printk(KERN_WARNING "Can not alloc sched group node list\n");
-		goto free_tmpmask;
-	}
-#endif
-
-	rd = alloc_rootdomain();
-	if (!rd) {
+		return sa_notcovered;
+	}
+	sched_group_nodes_bycpu[cpumask_first(cpu_map)] = d->sched_group_nodes;
+#endif
+	if (!alloc_cpumask_var(&d->nodemask, GFP_KERNEL))
+		return sa_sched_group_nodes;
+	if (!alloc_cpumask_var(&d->this_sibling_map, GFP_KERNEL))
+		return sa_nodemask;
+	if (!alloc_cpumask_var(&d->this_core_map, GFP_KERNEL))
+		return sa_this_sibling_map;
+	if (!alloc_cpumask_var(&d->send_covered, GFP_KERNEL))
+		return sa_this_core_map;
+	if (!alloc_cpumask_var(&d->tmpmask, GFP_KERNEL))
+		return sa_send_covered;
+	d->rd = alloc_rootdomain();
+	if (!d->rd) {
 		printk(KERN_WARNING "Cannot alloc root domain\n");
-		goto free_sched_groups;
+		return sa_tmpmask;
 	}
+	return sa_rootdomain;
+}
 
+static struct sched_domain *__build_numa_sched_domains(struct s_data *d,
+	const struct cpumask *cpu_map, struct sched_domain_attr *attr, int i)
+{
+	struct sched_domain *sd = NULL;
 #ifdef CONFIG_NUMA
-	sched_group_nodes_bycpu[cpumask_first(cpu_map)] = sched_group_nodes;
-#endif
-
-	/*
-	 * Set up domains for cpus specified by the cpu_map.
-	 */
-	for_each_cpu(i, cpu_map) {
-		struct sched_domain *sd = NULL, *p;
-
-		cpumask_and(nodemask, cpumask_of_node(cpu_to_node(i)), cpu_map);
-
-#ifdef CONFIG_NUMA
-		if (cpumask_weight(cpu_map) >
-				SD_NODES_PER_DOMAIN*cpumask_weight(nodemask)) {
-			sd = &per_cpu(allnodes_domains, i).sd;
-			SD_INIT(sd, ALLNODES);
-			set_domain_attribute(sd, attr);
-			cpumask_copy(sched_domain_span(sd), cpu_map);
-			cpu_to_allnodes_group(i, cpu_map, &sd->groups, tmpmask);
-			p = sd;
-			sd_allnodes = 1;
-		} else
-			p = NULL;
+	struct sched_domain *parent;
 
-		sd = &per_cpu(node_domains, i).sd;
-		SD_INIT(sd, NODE);
+	d->sd_allnodes = 0;
+	if (cpumask_weight(cpu_map) >
+	    SD_NODES_PER_DOMAIN * cpumask_weight(d->nodemask)) {
+		sd = &per_cpu(allnodes_domains, i).sd;
+		SD_INIT(sd, ALLNODES);
 		set_domain_attribute(sd, attr);
-		sched_domain_node_span(cpu_to_node(i), sched_domain_span(sd));
-		sd->parent = p;
-		if (p)
-			p->child = sd;
-		cpumask_and(sched_domain_span(sd),
-			    sched_domain_span(sd), cpu_map);
+		cpumask_copy(sched_domain_span(sd), cpu_map);
+		cpu_to_allnodes_group(i, cpu_map, &sd->groups, d->tmpmask);
+		d->sd_allnodes = 1;
+	}
+	parent = sd;
+
+	sd = &per_cpu(node_domains, i).sd;
+	SD_INIT(sd, NODE);
+	set_domain_attribute(sd, attr);
+	sched_domain_node_span(cpu_to_node(i), sched_domain_span(sd));
+	sd->parent = parent;
+	if (parent)
+		parent->child = sd;
+	cpumask_and(sched_domain_span(sd), sched_domain_span(sd), cpu_map);
 #endif
+	return sd;
+}
 
-		p = sd;
-		sd = &per_cpu(phys_domains, i).sd;
-		SD_INIT(sd, CPU);
-		set_domain_attribute(sd, attr);
-		cpumask_copy(sched_domain_span(sd), nodemask);
-		sd->parent = p;
-		if (p)
-			p->child = sd;
-		cpu_to_phys_group(i, cpu_map, &sd->groups, tmpmask);
+static struct sched_domain *__build_cpu_sched_domain(struct s_data *d,
+	const struct cpumask *cpu_map, struct sched_domain_attr *attr,
+	struct sched_domain *parent, int i)
+{
+	struct sched_domain *sd;
+	sd = &per_cpu(phys_domains, i).sd;
+	SD_INIT(sd, CPU);
+	set_domain_attribute(sd, attr);
+	cpumask_copy(sched_domain_span(sd), d->nodemask);
+	sd->parent = parent;
+	if (parent)
+		parent->child = sd;
+	cpu_to_phys_group(i, cpu_map, &sd->groups, d->tmpmask);
+	return sd;
+}
 
+static struct sched_domain *__build_mc_sched_domain(struct s_data *d,
+	const struct cpumask *cpu_map, struct sched_domain_attr *attr,
+	struct sched_domain *parent, int i)
+{
+	struct sched_domain *sd = parent;
 #ifdef CONFIG_SCHED_MC
-		p = sd;
-		sd = &per_cpu(core_domains, i).sd;
-		SD_INIT(sd, MC);
-		set_domain_attribute(sd, attr);
-		cpumask_and(sched_domain_span(sd), cpu_map,
-						   cpu_coregroup_mask(i));
-		sd->parent = p;
-		p->child = sd;
-		cpu_to_core_group(i, cpu_map, &sd->groups, tmpmask);
+	sd = &per_cpu(core_domains, i).sd;
+	SD_INIT(sd, MC);
+	set_domain_attribute(sd, attr);
+	cpumask_and(sched_domain_span(sd), cpu_map, cpu_coregroup_mask(i));
+	sd->parent = parent;
+	parent->child = sd;
+	cpu_to_core_group(i, cpu_map, &sd->groups, d->tmpmask);
 #endif
+	return sd;
+}
 
+static struct sched_domain *__build_smt_sched_domain(struct s_data *d,
+	const struct cpumask *cpu_map, struct sched_domain_attr *attr,
+	struct sched_domain *parent, int i)
+{
+	struct sched_domain *sd = parent;
 #ifdef CONFIG_SCHED_SMT
-		p = sd;
-		sd = &per_cpu(cpu_domains, i).sd;
-		SD_INIT(sd, SIBLING);
-		set_domain_attribute(sd, attr);
-		cpumask_and(sched_domain_span(sd),
-			    topology_thread_cpumask(i), cpu_map);
-		sd->parent = p;
-		p->child = sd;
-		cpu_to_cpu_group(i, cpu_map, &sd->groups, tmpmask);
+	sd = &per_cpu(cpu_domains, i).sd;
+	SD_INIT(sd, SIBLING);
+	set_domain_attribute(sd, attr);
+	cpumask_and(sched_domain_span(sd), cpu_map, topology_thread_cpumask(i));
+	sd->parent = parent;
+	parent->child = sd;
+	cpu_to_cpu_group(i, cpu_map, &sd->groups, d->tmpmask);
 #endif
-	}
+	return sd;
+}
 
+static void build_sched_groups(struct s_data *d, enum sched_domain_level l,
+			       const struct cpumask *cpu_map, int cpu)
+{
+	switch (l) {
 #ifdef CONFIG_SCHED_SMT
-	/* Set up CPU (sibling) groups */
-	for_each_cpu(i, cpu_map) {
-		cpumask_and(this_sibling_map,
-			    topology_thread_cpumask(i), cpu_map);
-		if (i != cpumask_first(this_sibling_map))
-			continue;
-
-		init_sched_build_groups(this_sibling_map, cpu_map,
-					&cpu_to_cpu_group,
-					send_covered, tmpmask);
-	}
+	case SD_LV_SIBLING: /* set up CPU (sibling) groups */
+		cpumask_and(d->this_sibling_map, cpu_map,
+			    topology_thread_cpumask(cpu));
+		if (cpu == cpumask_first(d->this_sibling_map))
+			init_sched_build_groups(d->this_sibling_map, cpu_map,
+						&cpu_to_cpu_group,
+						d->send_covered, d->tmpmask);
+		break;
 #endif
-
 #ifdef CONFIG_SCHED_MC
-	/* Set up multi-core groups */
-	for_each_cpu(i, cpu_map) {
-		cpumask_and(this_core_map, cpu_coregroup_mask(i), cpu_map);
-		if (i != cpumask_first(this_core_map))
-			continue;
-
-		init_sched_build_groups(this_core_map, cpu_map,
-					&cpu_to_core_group,
-					send_covered, tmpmask);
-	}
+	case SD_LV_MC: /* set up multi-core groups */
+		cpumask_and(d->this_core_map, cpu_map, cpu_coregroup_mask(cpu));
+		if (cpu == cpumask_first(d->this_core_map))
+			init_sched_build_groups(d->this_core_map, cpu_map,
+						&cpu_to_core_group,
+						d->send_covered, d->tmpmask);
+		break;
 #endif
-
-	/* Set up physical groups */
-	for (i = 0; i < nr_node_ids; i++) {
-		cpumask_and(nodemask, cpumask_of_node(i), cpu_map);
-		if (cpumask_empty(nodemask))
-			continue;
-
-		init_sched_build_groups(nodemask, cpu_map,
-					&cpu_to_phys_group,
-					send_covered, tmpmask);
-	}
-
+	case SD_LV_CPU: /* set up physical groups */
+		cpumask_and(d->nodemask, cpumask_of_node(cpu), cpu_map);
+		if (!cpumask_empty(d->nodemask))
+			init_sched_build_groups(d->nodemask, cpu_map,
+						&cpu_to_phys_group,
+						d->send_covered, d->tmpmask);
+		break;
 #ifdef CONFIG_NUMA
-	/* Set up node groups */
-	if (sd_allnodes) {
-		init_sched_build_groups(cpu_map, cpu_map,
-					&cpu_to_allnodes_group,
-					send_covered, tmpmask);
+	case SD_LV_ALLNODES:
+		init_sched_build_groups(cpu_map, cpu_map, &cpu_to_allnodes_group,
+					d->send_covered, d->tmpmask);
+		break;
+#endif
+	default:
+		break;
 	}
+}
 
-	for (i = 0; i < nr_node_ids; i++) {
-		/* Set up node groups */
-		struct sched_group *sg, *prev;
-		int j;
-
-		cpumask_clear(covered);
-		cpumask_and(nodemask, cpumask_of_node(i), cpu_map);
-		if (cpumask_empty(nodemask)) {
-			sched_group_nodes[i] = NULL;
-			continue;
-		}
+/*
+ * Build sched domains for a given set of cpus and attach the sched domains
+ * to the individual cpus
+ */
+static int __build_sched_domains(const struct cpumask *cpu_map,
+				 struct sched_domain_attr *attr)
+{
+	enum s_alloc alloc_state = sa_none;
+	struct s_data d;
+	struct sched_domain *sd;
+	int i;
+#ifdef CONFIG_NUMA
+	d.sd_allnodes = 0;
+#endif
 
-		sched_domain_node_span(i, domainspan);
-		cpumask_and(domainspan, domainspan, cpu_map);
+	alloc_state = __visit_domain_allocation_hell(&d, cpu_map);
+	if (alloc_state != sa_rootdomain)
+		goto error;
+	alloc_state = sa_sched_groups;
 
-		sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(),
-				  GFP_KERNEL, i);
-		if (!sg) {
-			printk(KERN_WARNING "Can not alloc domain group for "
-				"node %d\n", i);
-			goto error;
-		}
-		sched_group_nodes[i] = sg;
-		for_each_cpu(j, nodemask) {
-			struct sched_domain *sd;
+	/*
+	 * Set up domains for cpus specified by the cpu_map.
+	 */
+	for_each_cpu(i, cpu_map) {
+		cpumask_and(d.nodemask, cpumask_of_node(cpu_to_node(i)),
+			    cpu_map);
 
-			sd = &per_cpu(node_domains, j).sd;
-			sd->groups = sg;
-		}
-		sg->__cpu_power = 0;
-		cpumask_copy(sched_group_cpus(sg), nodemask);
-		sg->next = sg;
-		cpumask_or(covered, covered, nodemask);
-		prev = sg;
+		sd = __build_numa_sched_domains(&d, cpu_map, attr, i);
+		sd = __build_cpu_sched_domain(&d, cpu_map, attr, sd, i);
+		sd = __build_mc_sched_domain(&d, cpu_map, attr, sd, i);
+		sd = __build_smt_sched_domain(&d, cpu_map, attr, sd, i);
+	}
 
-		for (j = 0; j < nr_node_ids; j++) {
-			int n = (i + j) % nr_node_ids;
+	for_each_cpu(i, cpu_map) {
+		build_sched_groups(&d, SD_LV_SIBLING, cpu_map, i);
+		build_sched_groups(&d, SD_LV_MC, cpu_map, i);
+	}
 
-			cpumask_complement(notcovered, covered);
-			cpumask_and(tmpmask, notcovered, cpu_map);
-			cpumask_and(tmpmask, tmpmask, domainspan);
-			if (cpumask_empty(tmpmask))
-				break;
+	/* Set up physical groups */
+	for (i = 0; i < nr_node_ids; i++)
+		build_sched_groups(&d, SD_LV_CPU, cpu_map, i);
 
-			cpumask_and(tmpmask, tmpmask, cpumask_of_node(n));
-			if (cpumask_empty(tmpmask))
-				continue;
+#ifdef CONFIG_NUMA
+	/* Set up node groups */
+	if (d.sd_allnodes)
+		build_sched_groups(&d, SD_LV_ALLNODES, cpu_map, 0);
 
-			sg = kmalloc_node(sizeof(struct sched_group) +
-					  cpumask_size(),
-					  GFP_KERNEL, i);
-			if (!sg) {
-				printk(KERN_WARNING
-				"Can not alloc domain group for node %d\n", j);
-				goto error;
-			}
-			sg->__cpu_power = 0;
-			cpumask_copy(sched_group_cpus(sg), tmpmask);
-			sg->next = prev->next;
-			cpumask_or(covered, covered, tmpmask);
-			prev->next = sg;
-			prev = sg;
-		}
-	}
+	for (i = 0; i < nr_node_ids; i++)
+		if (build_numa_sched_groups(&d, cpu_map, i))
+			goto error;
 #endif
 
 	/* Calculate CPU power for physical packages and nodes */
 #ifdef CONFIG_SCHED_SMT
 	for_each_cpu(i, cpu_map) {
-		struct sched_domain *sd = &per_cpu(cpu_domains, i).sd;
-
+		sd = &per_cpu(cpu_domains, i).sd;
 		init_sched_groups_power(i, sd);
 	}
 #endif
 #ifdef CONFIG_SCHED_MC
 	for_each_cpu(i, cpu_map) {
-		struct sched_domain *sd = &per_cpu(core_domains, i).sd;
-
+		sd = &per_cpu(core_domains, i).sd;
 		init_sched_groups_power(i, sd);
 	}
 #endif
 
 	for_each_cpu(i, cpu_map) {
-		struct sched_domain *sd = &per_cpu(phys_domains, i).sd;
-
+		sd = &per_cpu(phys_domains, i).sd;
 		init_sched_groups_power(i, sd);
 	}
 
 #ifdef CONFIG_NUMA
 	for (i = 0; i < nr_node_ids; i++)
-		init_numa_sched_groups_power(sched_group_nodes[i]);
+		init_numa_sched_groups_power(d.sched_group_nodes[i]);
 
-	if (sd_allnodes) {
+	if (d.sd_allnodes) {
 		struct sched_group *sg;
 
 		cpu_to_allnodes_group(cpumask_first(cpu_map), cpu_map, &sg,
-								tmpmask);
+								d.tmpmask);
 		init_numa_sched_groups_power(sg);
 	}
 #endif
 
 	/* Attach the domains */
 	for_each_cpu(i, cpu_map) {
-		struct sched_domain *sd;
 #ifdef CONFIG_SCHED_SMT
 		sd = &per_cpu(cpu_domains, i).sd;
 #elif defined(CONFIG_SCHED_MC)
@@ -8659,44 +8834,16 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
 #else
 		sd = &per_cpu(phys_domains, i).sd;
 #endif
-		cpu_attach_domain(sd, rd, i);
+		cpu_attach_domain(sd, d.rd, i);
 	}
 
-	err = 0;
-
-free_tmpmask:
-	free_cpumask_var(tmpmask);
-free_send_covered:
-	free_cpumask_var(send_covered);
-free_this_core_map:
-	free_cpumask_var(this_core_map);
-free_this_sibling_map:
-	free_cpumask_var(this_sibling_map);
-free_nodemask:
-	free_cpumask_var(nodemask);
-free_notcovered:
-#ifdef CONFIG_NUMA
-	free_cpumask_var(notcovered);
-free_covered:
-	free_cpumask_var(covered);
-free_domainspan:
-	free_cpumask_var(domainspan);
-out:
-#endif
-	return err;
-
-free_sched_groups:
-#ifdef CONFIG_NUMA
-	kfree(sched_group_nodes);
-#endif
-	goto free_tmpmask;
+	d.sched_group_nodes = NULL; /* don't free this we still need it */
+	__free_domain_allocs(&d, sa_tmpmask, cpu_map);
+	return 0;
 
-#ifdef CONFIG_NUMA
 error:
-	free_sched_groups(cpu_map, tmpmask);
-	free_rootdomain(rd);
-	goto free_tmpmask;
-#endif
+	__free_domain_allocs(&d, alloc_state, cpu_map);
+	return -ENOMEM;
 }
 
 static int build_sched_domains(const struct cpumask *cpu_map)
@@ -9015,6 +9162,7 @@ void __init sched_init_smp(void)
 	cpumask_var_t non_isolated_cpus;
 
 	alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL);
+	alloc_cpumask_var(&fallback_doms, GFP_KERNEL);
 
 #if defined(CONFIG_NUMA)
 	sched_group_nodes_bycpu = kzalloc(nr_cpu_ids * sizeof(void **),
@@ -9046,7 +9194,6 @@ void __init sched_init_smp(void)
 	sched_init_granularity();
 	free_cpumask_var(non_isolated_cpus);
 
-	alloc_cpumask_var(&fallback_doms, GFP_KERNEL);
 	init_sched_rt_class();
 }
 #else
@@ -9304,11 +9451,11 @@ void __init sched_init(void)
 		 * system cpu resource, based on the weight assigned to root
 		 * user's cpu share (INIT_TASK_GROUP_LOAD). This is accomplished
 		 * by letting tasks of init_task_group sit in a separate cfs_rq
-		 * (init_cfs_rq) and having one entity represent this group of
+		 * (init_tg_cfs_rq) and having one entity represent this group of
 		 * tasks in rq->cfs (i.e init_task_group->se[] != NULL).
 		 */
 		init_tg_cfs_entry(&init_task_group,
-				&per_cpu(init_cfs_rq, i),
+				&per_cpu(init_tg_cfs_rq, i),
 				&per_cpu(init_sched_entity, i), i, 1,
 				root_task_group.se[i]);
 
@@ -9334,6 +9481,7 @@ void __init sched_init(void)
 #ifdef CONFIG_SMP
 		rq->sd = NULL;
 		rq->rd = NULL;
+		rq->post_schedule = 0;
 		rq->active_balance = 0;
 		rq->next_balance = jiffies;
 		rq->push_cpu = 0;
@@ -9392,19 +9540,26 @@ void __init sched_init(void)
 	alloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT);
 #endif /* SMP */
 
-	perf_counter_init();
+	perf_event_init();
 
 	scheduler_running = 1;
 }
 
 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
-void __might_sleep(char *file, int line)
+static inline int preempt_count_equals(int preempt_offset)
+{
+	int nested = preempt_count() & ~PREEMPT_ACTIVE;
+
+	return (nested == PREEMPT_INATOMIC_BASE + preempt_offset);
+}
+
+void __might_sleep(char *file, int line, int preempt_offset)
 {
 #ifdef in_atomic
 	static unsigned long prev_jiffy;	/* ratelimiting */
 
-	if ((!in_atomic() && !irqs_disabled()) ||
-		    system_state != SYSTEM_RUNNING || oops_in_progress)
+	if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) ||
+	    system_state != SYSTEM_RUNNING || oops_in_progress)
 		return;
 	if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
 		return;
@@ -10581,3 +10736,113 @@ struct cgroup_subsys cpuacct_subsys = {
 	.subsys_id = cpuacct_subsys_id,
 };
 #endif	/* CONFIG_CGROUP_CPUACCT */
+
+#ifndef CONFIG_SMP
+
+int rcu_expedited_torture_stats(char *page)
+{
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rcu_expedited_torture_stats);
+
+void synchronize_sched_expedited(void)
+{
+}
+EXPORT_SYMBOL_GPL(synchronize_sched_expedited);
+
+#else /* #ifndef CONFIG_SMP */
+
+static DEFINE_PER_CPU(struct migration_req, rcu_migration_req);
+static DEFINE_MUTEX(rcu_sched_expedited_mutex);
+
+#define RCU_EXPEDITED_STATE_POST -2
+#define RCU_EXPEDITED_STATE_IDLE -1
+
+static int rcu_expedited_state = RCU_EXPEDITED_STATE_IDLE;
+
+int rcu_expedited_torture_stats(char *page)
+{
+	int cnt = 0;
+	int cpu;
+
+	cnt += sprintf(&page[cnt], "state: %d /", rcu_expedited_state);
+	for_each_online_cpu(cpu) {
+		 cnt += sprintf(&page[cnt], " %d:%d",
+				cpu, per_cpu(rcu_migration_req, cpu).dest_cpu);
+	}
+	cnt += sprintf(&page[cnt], "\n");
+	return cnt;
+}
+EXPORT_SYMBOL_GPL(rcu_expedited_torture_stats);
+
+static long synchronize_sched_expedited_count;
+
+/*
+ * Wait for an rcu-sched grace period to elapse, but use "big hammer"
+ * approach to force grace period to end quickly.  This consumes
+ * significant time on all CPUs, and is thus not recommended for
+ * any sort of common-case code.
+ *
+ * Note that it is illegal to call this function while holding any
+ * lock that is acquired by a CPU-hotplug notifier.  Failing to
+ * observe this restriction will result in deadlock.
+ */
+void synchronize_sched_expedited(void)
+{
+	int cpu;
+	unsigned long flags;
+	bool need_full_sync = 0;
+	struct rq *rq;
+	struct migration_req *req;
+	long snap;
+	int trycount = 0;
+
+	smp_mb();  /* ensure prior mod happens before capturing snap. */
+	snap = ACCESS_ONCE(synchronize_sched_expedited_count) + 1;
+	get_online_cpus();
+	while (!mutex_trylock(&rcu_sched_expedited_mutex)) {
+		put_online_cpus();
+		if (trycount++ < 10)
+			udelay(trycount * num_online_cpus());
+		else {
+			synchronize_sched();
+			return;
+		}
+		if (ACCESS_ONCE(synchronize_sched_expedited_count) - snap > 0) {
+			smp_mb(); /* ensure test happens before caller kfree */
+			return;
+		}
+		get_online_cpus();
+	}
+	rcu_expedited_state = RCU_EXPEDITED_STATE_POST;
+	for_each_online_cpu(cpu) {
+		rq = cpu_rq(cpu);
+		req = &per_cpu(rcu_migration_req, cpu);
+		init_completion(&req->done);
+		req->task = NULL;
+		req->dest_cpu = RCU_MIGRATION_NEED_QS;
+		spin_lock_irqsave(&rq->lock, flags);
+		list_add(&req->list, &rq->migration_queue);
+		spin_unlock_irqrestore(&rq->lock, flags);
+		wake_up_process(rq->migration_thread);
+	}
+	for_each_online_cpu(cpu) {
+		rcu_expedited_state = cpu;
+		req = &per_cpu(rcu_migration_req, cpu);
+		rq = cpu_rq(cpu);
+		wait_for_completion(&req->done);
+		spin_lock_irqsave(&rq->lock, flags);
+		if (unlikely(req->dest_cpu == RCU_MIGRATION_MUST_SYNC))
+			need_full_sync = 1;
+		req->dest_cpu = RCU_MIGRATION_IDLE;
+		spin_unlock_irqrestore(&rq->lock, flags);
+	}
+	rcu_expedited_state = RCU_EXPEDITED_STATE_IDLE;
+	mutex_unlock(&rcu_sched_expedited_mutex);
+	put_online_cpus();
+	if (need_full_sync)
+		synchronize_sched();
+}
+EXPORT_SYMBOL_GPL(synchronize_sched_expedited);
+
+#endif /* #else #ifndef CONFIG_SMP */
diff --git a/kernel/sched_clock.c b/kernel/sched_clock.c
index e1d16c9..ac2e1dc 100644
--- a/kernel/sched_clock.c
+++ b/kernel/sched_clock.c
@@ -48,13 +48,6 @@ static __read_mostly int sched_clock_running;
 __read_mostly int sched_clock_stable;
 
 struct sched_clock_data {
-	/*
-	 * Raw spinlock - this is a special case: this might be called
-	 * from within instrumentation code so we dont want to do any
-	 * instrumentation ourselves.
-	 */
-	raw_spinlock_t		lock;
-
 	u64			tick_raw;
 	u64			tick_gtod;
 	u64			clock;
@@ -80,7 +73,6 @@ void sched_clock_init(void)
 	for_each_possible_cpu(cpu) {
 		struct sched_clock_data *scd = cpu_sdc(cpu);
 
-		scd->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
 		scd->tick_raw = 0;
 		scd->tick_gtod = ktime_now;
 		scd->clock = ktime_now;
@@ -109,14 +101,19 @@ static inline u64 wrap_max(u64 x, u64 y)
  *  - filter out backward motion
  *  - use the GTOD tick value to create a window to filter crazy TSC values
  */
-static u64 __update_sched_clock(struct sched_clock_data *scd, u64 now)
+static u64 sched_clock_local(struct sched_clock_data *scd)
 {
-	s64 delta = now - scd->tick_raw;
-	u64 clock, min_clock, max_clock;
+	u64 now, clock, old_clock, min_clock, max_clock;
+	s64 delta;
 
+again:
+	now = sched_clock();
+	delta = now - scd->tick_raw;
 	if (unlikely(delta < 0))
 		delta = 0;
 
+	old_clock = scd->clock;
+
 	/*
 	 * scd->clock = clamp(scd->tick_gtod + delta,
 	 *		      max(scd->tick_gtod, scd->clock),
@@ -124,84 +121,73 @@ static u64 __update_sched_clock(struct sched_clock_data *scd, u64 now)
 	 */
 
 	clock = scd->tick_gtod + delta;
-	min_clock = wrap_max(scd->tick_gtod, scd->clock);
-	max_clock = wrap_max(scd->clock, scd->tick_gtod + TICK_NSEC);
+	min_clock = wrap_max(scd->tick_gtod, old_clock);
+	max_clock = wrap_max(old_clock, scd->tick_gtod + TICK_NSEC);
 
 	clock = wrap_max(clock, min_clock);
 	clock = wrap_min(clock, max_clock);
 
-	scd->clock = clock;
+	if (cmpxchg(&scd->clock, old_clock, clock) != old_clock)
+		goto again;
 
-	return scd->clock;
+	return clock;
 }
 
-static void lock_double_clock(struct sched_clock_data *data1,
-				struct sched_clock_data *data2)
+static u64 sched_clock_remote(struct sched_clock_data *scd)
 {
-	if (data1 < data2) {
-		__raw_spin_lock(&data1->lock);
-		__raw_spin_lock(&data2->lock);
+	struct sched_clock_data *my_scd = this_scd();
+	u64 this_clock, remote_clock;
+	u64 *ptr, old_val, val;
+
+	sched_clock_local(my_scd);
+again:
+	this_clock = my_scd->clock;
+	remote_clock = scd->clock;
+
+	/*
+	 * Use the opportunity that we have both locks
+	 * taken to couple the two clocks: we take the
+	 * larger time as the latest time for both
+	 * runqueues. (this creates monotonic movement)
+	 */
+	if (likely((s64)(remote_clock - this_clock) < 0)) {
+		ptr = &scd->clock;
+		old_val = remote_clock;
+		val = this_clock;
 	} else {
-		__raw_spin_lock(&data2->lock);
-		__raw_spin_lock(&data1->lock);
+		/*
+		 * Should be rare, but possible:
+		 */
+		ptr = &my_scd->clock;
+		old_val = this_clock;
+		val = remote_clock;
 	}
+
+	if (cmpxchg(ptr, old_val, val) != old_val)
+		goto again;
+
+	return val;
 }
 
 u64 sched_clock_cpu(int cpu)
 {
-	u64 now, clock, this_clock, remote_clock;
 	struct sched_clock_data *scd;
+	u64 clock;
+
+	WARN_ON_ONCE(!irqs_disabled());
 
 	if (sched_clock_stable)
 		return sched_clock();
 
-	scd = cpu_sdc(cpu);
-
-	/*
-	 * Normally this is not called in NMI context - but if it is,
-	 * trying to do any locking here is totally lethal.
-	 */
-	if (unlikely(in_nmi()))
-		return scd->clock;
-
 	if (unlikely(!sched_clock_running))
 		return 0ull;
 
-	WARN_ON_ONCE(!irqs_disabled());
-	now = sched_clock();
-
-	if (cpu != raw_smp_processor_id()) {
-		struct sched_clock_data *my_scd = this_scd();
-
-		lock_double_clock(scd, my_scd);
-
-		this_clock = __update_sched_clock(my_scd, now);
-		remote_clock = scd->clock;
-
-		/*
-		 * Use the opportunity that we have both locks
-		 * taken to couple the two clocks: we take the
-		 * larger time as the latest time for both
-		 * runqueues. (this creates monotonic movement)
-		 */
-		if (likely((s64)(remote_clock - this_clock) < 0)) {
-			clock = this_clock;
-			scd->clock = clock;
-		} else {
-			/*
-			 * Should be rare, but possible:
-			 */
-			clock = remote_clock;
-			my_scd->clock = remote_clock;
-		}
-
-		__raw_spin_unlock(&my_scd->lock);
-	} else {
-		__raw_spin_lock(&scd->lock);
-		clock = __update_sched_clock(scd, now);
-	}
+	scd = cpu_sdc(cpu);
 
-	__raw_spin_unlock(&scd->lock);
+	if (cpu != smp_processor_id())
+		clock = sched_clock_remote(scd);
+	else
+		clock = sched_clock_local(scd);
 
 	return clock;
 }
@@ -223,11 +209,9 @@ void sched_clock_tick(void)
 	now_gtod = ktime_to_ns(ktime_get());
 	now = sched_clock();
 
-	__raw_spin_lock(&scd->lock);
 	scd->tick_raw = now;
 	scd->tick_gtod = now_gtod;
-	__update_sched_clock(scd, now);
-	__raw_spin_unlock(&scd->lock);
+	sched_clock_local(scd);
 }
 
 /*
diff --git a/kernel/sched_cpupri.c b/kernel/sched_cpupri.c
index d014efb..0f052fc 100644
--- a/kernel/sched_cpupri.c
+++ b/kernel/sched_cpupri.c
@@ -127,21 +127,11 @@ void cpupri_set(struct cpupri *cp, int cpu, int newpri)
 
 	/*
 	 * If the cpu was currently mapped to a different value, we
-	 * first need to unmap the old value
+	 * need to map it to the new value then remove the old value.
+	 * Note, we must add the new value first, otherwise we risk the
+	 * cpu being cleared from pri_active, and this cpu could be
+	 * missed for a push or pull.
 	 */
-	if (likely(oldpri != CPUPRI_INVALID)) {
-		struct cpupri_vec *vec  = &cp->pri_to_cpu[oldpri];
-
-		spin_lock_irqsave(&vec->lock, flags);
-
-		vec->count--;
-		if (!vec->count)
-			clear_bit(oldpri, cp->pri_active);
-		cpumask_clear_cpu(cpu, vec->mask);
-
-		spin_unlock_irqrestore(&vec->lock, flags);
-	}
-
 	if (likely(newpri != CPUPRI_INVALID)) {
 		struct cpupri_vec *vec = &cp->pri_to_cpu[newpri];
 
@@ -154,6 +144,18 @@ void cpupri_set(struct cpupri *cp, int cpu, int newpri)
 
 		spin_unlock_irqrestore(&vec->lock, flags);
 	}
+	if (likely(oldpri != CPUPRI_INVALID)) {
+		struct cpupri_vec *vec  = &cp->pri_to_cpu[oldpri];
+
+		spin_lock_irqsave(&vec->lock, flags);
+
+		vec->count--;
+		if (!vec->count)
+			clear_bit(oldpri, cp->pri_active);
+		cpumask_clear_cpu(cpu, vec->mask);
+
+		spin_unlock_irqrestore(&vec->lock, flags);
+	}
 
 	*currpri = newpri;
 }
diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c
index 70c7e0b..efb8440 100644
--- a/kernel/sched_debug.c
+++ b/kernel/sched_debug.c
@@ -395,6 +395,7 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 	PN(se.sum_exec_runtime);
 	PN(se.avg_overlap);
 	PN(se.avg_wakeup);
+	PN(se.avg_running);
 
 	nr_switches = p->nvcsw + p->nivcsw;
 
@@ -409,6 +410,8 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 	PN(se.wait_max);
 	PN(se.wait_sum);
 	P(se.wait_count);
+	PN(se.iowait_sum);
+	P(se.iowait_count);
 	P(sched_info.bkl_count);
 	P(se.nr_migrations);
 	P(se.nr_migrations_cold);
@@ -479,6 +482,8 @@ void proc_sched_set_task(struct task_struct *p)
 	p->se.wait_max				= 0;
 	p->se.wait_sum				= 0;
 	p->se.wait_count			= 0;
+	p->se.iowait_sum			= 0;
+	p->se.iowait_count			= 0;
 	p->se.sleep_max				= 0;
 	p->se.sum_sleep_runtime			= 0;
 	p->se.block_max				= 0;
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 652e8bd..ecc637a 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -24,7 +24,7 @@
 
 /*
  * Targeted preemption latency for CPU-bound tasks:
- * (default: 20ms * (1 + ilog(ncpus)), units: nanoseconds)
+ * (default: 5ms * (1 + ilog(ncpus)), units: nanoseconds)
  *
  * NOTE: this latency value is not the same as the concept of
  * 'timeslice length' - timeslices in CFS are of variable length
@@ -34,13 +34,13 @@
  * (to see the precise effective timeslice length of your workload,
  *  run vmstat and monitor the context-switches (cs) field)
  */
-unsigned int sysctl_sched_latency = 20000000ULL;
+unsigned int sysctl_sched_latency = 5000000ULL;
 
 /*
  * Minimal preemption granularity for CPU-bound tasks:
- * (default: 4 msec * (1 + ilog(ncpus)), units: nanoseconds)
+ * (default: 1 msec * (1 + ilog(ncpus)), units: nanoseconds)
  */
-unsigned int sysctl_sched_min_granularity = 4000000ULL;
+unsigned int sysctl_sched_min_granularity = 1000000ULL;
 
 /*
  * is kept at sysctl_sched_latency / sysctl_sched_min_granularity
@@ -48,10 +48,10 @@ unsigned int sysctl_sched_min_granularity = 4000000ULL;
 static unsigned int sched_nr_latency = 5;
 
 /*
- * After fork, child runs first. (default) If set to 0 then
+ * After fork, child runs first. If set to 0 (default) then
  * parent will (try to) run first.
  */
-const_debug unsigned int sysctl_sched_child_runs_first = 1;
+unsigned int sysctl_sched_child_runs_first __read_mostly;
 
 /*
  * sys_sched_yield() compat mode
@@ -63,13 +63,13 @@ unsigned int __read_mostly sysctl_sched_compat_yield;
 
 /*
  * SCHED_OTHER wake-up granularity.
- * (default: 5 msec * (1 + ilog(ncpus)), units: nanoseconds)
+ * (default: 1 msec * (1 + ilog(ncpus)), units: nanoseconds)
  *
  * This option delays the preemption effects of decoupled workloads
  * and reduces their over-scheduling. Synchronous workloads will still
  * have immediate wakeup/sleep latencies.
  */
-unsigned int sysctl_sched_wakeup_granularity = 5000000UL;
+unsigned int sysctl_sched_wakeup_granularity = 1000000UL;
 
 const_debug unsigned int sysctl_sched_migration_cost = 500000UL;
 
@@ -79,11 +79,6 @@ static const struct sched_class fair_sched_class;
  * CFS operations on generic schedulable entities:
  */
 
-static inline struct task_struct *task_of(struct sched_entity *se)
-{
-	return container_of(se, struct task_struct, se);
-}
-
 #ifdef CONFIG_FAIR_GROUP_SCHED
 
 /* cpu runqueue to which this cfs_rq is attached */
@@ -95,6 +90,14 @@ static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
 /* An entity is a task if it doesn't "own" a runqueue */
 #define entity_is_task(se)	(!se->my_q)
 
+static inline struct task_struct *task_of(struct sched_entity *se)
+{
+#ifdef CONFIG_SCHED_DEBUG
+	WARN_ON_ONCE(!entity_is_task(se));
+#endif
+	return container_of(se, struct task_struct, se);
+}
+
 /* Walk up scheduling entities hierarchy */
 #define for_each_sched_entity(se) \
 		for (; se; se = se->parent)
@@ -186,7 +189,12 @@ find_matching_se(struct sched_entity **se, struct sched_entity **pse)
 	}
 }
 
-#else	/* CONFIG_FAIR_GROUP_SCHED */
+#else	/* !CONFIG_FAIR_GROUP_SCHED */
+
+static inline struct task_struct *task_of(struct sched_entity *se)
+{
+	return container_of(se, struct task_struct, se);
+}
 
 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
 {
@@ -505,6 +513,7 @@ static void update_curr(struct cfs_rq *cfs_rq)
 	if (entity_is_task(curr)) {
 		struct task_struct *curtask = task_of(curr);
 
+		trace_sched_stat_runtime(curtask, delta_exec, curr->vruntime);
 		cpuacct_charge(curtask, delta_exec);
 		account_group_exec_runtime(curtask, delta_exec);
 	}
@@ -537,6 +546,12 @@ update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
 	schedstat_set(se->wait_count, se->wait_count + 1);
 	schedstat_set(se->wait_sum, se->wait_sum +
 			rq_of(cfs_rq)->clock - se->wait_start);
+#ifdef CONFIG_SCHEDSTATS
+	if (entity_is_task(se)) {
+		trace_sched_stat_wait(task_of(se),
+			rq_of(cfs_rq)->clock - se->wait_start);
+	}
+#endif
 	schedstat_set(se->wait_start, 0);
 }
 
@@ -628,8 +643,10 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
 		se->sleep_start = 0;
 		se->sum_sleep_runtime += delta;
 
-		if (tsk)
+		if (tsk) {
 			account_scheduler_latency(tsk, delta >> 10, 1);
+			trace_sched_stat_sleep(tsk, delta);
+		}
 	}
 	if (se->block_start) {
 		u64 delta = rq_of(cfs_rq)->clock - se->block_start;
@@ -644,6 +661,12 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
 		se->sum_sleep_runtime += delta;
 
 		if (tsk) {
+			if (tsk->in_iowait) {
+				se->iowait_sum += delta;
+				se->iowait_count++;
+				trace_sched_stat_iowait(tsk, delta);
+			}
+
 			/*
 			 * Blocking time is in units of nanosecs, so shift by
 			 * 20 to get a milliseconds-range estimation of the
@@ -687,29 +710,33 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
 	if (initial && sched_feat(START_DEBIT))
 		vruntime += sched_vslice(cfs_rq, se);
 
-	if (!initial) {
-		/* sleeps upto a single latency don't count. */
-		if (sched_feat(NEW_FAIR_SLEEPERS)) {
-			unsigned long thresh = sysctl_sched_latency;
+	/* sleeps up to a single latency don't count. */
+	if (!initial && sched_feat(FAIR_SLEEPERS)) {
+		unsigned long thresh = sysctl_sched_latency;
 
-			/*
-			 * Convert the sleeper threshold into virtual time.
-			 * SCHED_IDLE is a special sub-class.  We care about
-			 * fairness only relative to other SCHED_IDLE tasks,
-			 * all of which have the same weight.
-			 */
-			if (sched_feat(NORMALIZED_SLEEPER) &&
-					(!entity_is_task(se) ||
-					 task_of(se)->policy != SCHED_IDLE))
-				thresh = calc_delta_fair(thresh, se);
+		/*
+		 * Convert the sleeper threshold into virtual time.
+		 * SCHED_IDLE is a special sub-class.  We care about
+		 * fairness only relative to other SCHED_IDLE tasks,
+		 * all of which have the same weight.
+		 */
+		if (sched_feat(NORMALIZED_SLEEPER) && (!entity_is_task(se) ||
+				 task_of(se)->policy != SCHED_IDLE))
+			thresh = calc_delta_fair(thresh, se);
 
-			vruntime -= thresh;
-		}
+		/*
+		 * Halve their sleep time's effect, to allow
+		 * for a gentler effect of sleepers:
+		 */
+		if (sched_feat(GENTLE_FAIR_SLEEPERS))
+			thresh >>= 1;
 
-		/* ensure we never gain time by being placed backwards. */
-		vruntime = max_vruntime(se->vruntime, vruntime);
+		vruntime -= thresh;
 	}
 
+	/* ensure we never gain time by being placed backwards. */
+	vruntime = max_vruntime(se->vruntime, vruntime);
+
 	se->vruntime = vruntime;
 }
 
@@ -735,10 +762,10 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int wakeup)
 
 static void __clear_buddies(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
-	if (cfs_rq->last == se)
+	if (!se || cfs_rq->last == se)
 		cfs_rq->last = NULL;
 
-	if (cfs_rq->next == se)
+	if (!se || cfs_rq->next == se)
 		cfs_rq->next = NULL;
 }
 
@@ -1040,79 +1067,6 @@ static void yield_task_fair(struct rq *rq)
 	se->vruntime = rightmost->vruntime + 1;
 }
 
-/*
- * wake_idle() will wake a task on an idle cpu if task->cpu is
- * not idle and an idle cpu is available.  The span of cpus to
- * search starts with cpus closest then further out as needed,
- * so we always favor a closer, idle cpu.
- * Domains may include CPUs that are not usable for migration,
- * hence we need to mask them out (cpu_active_mask)
- *
- * Returns the CPU we should wake onto.
- */
-#if defined(ARCH_HAS_SCHED_WAKE_IDLE)
-static int wake_idle(int cpu, struct task_struct *p)
-{
-	struct sched_domain *sd;
-	int i;
-	unsigned int chosen_wakeup_cpu;
-	int this_cpu;
-
-	/*
-	 * At POWERSAVINGS_BALANCE_WAKEUP level, if both this_cpu and prev_cpu
-	 * are idle and this is not a kernel thread and this task's affinity
-	 * allows it to be moved to preferred cpu, then just move!
-	 */
-
-	this_cpu = smp_processor_id();
-	chosen_wakeup_cpu =
-		cpu_rq(this_cpu)->rd->sched_mc_preferred_wakeup_cpu;
-
-	if (sched_mc_power_savings >= POWERSAVINGS_BALANCE_WAKEUP &&
-		idle_cpu(cpu) && idle_cpu(this_cpu) &&
-		p->mm && !(p->flags & PF_KTHREAD) &&
-		cpu_isset(chosen_wakeup_cpu, p->cpus_allowed))
-		return chosen_wakeup_cpu;
-
-	/*
-	 * If it is idle, then it is the best cpu to run this task.
-	 *
-	 * This cpu is also the best, if it has more than one task already.
-	 * Siblings must be also busy(in most cases) as they didn't already
-	 * pickup the extra load from this cpu and hence we need not check
-	 * sibling runqueue info. This will avoid the checks and cache miss
-	 * penalities associated with that.
-	 */
-	if (idle_cpu(cpu) || cpu_rq(cpu)->cfs.nr_running > 1)
-		return cpu;
-
-	for_each_domain(cpu, sd) {
-		if ((sd->flags & SD_WAKE_IDLE)
-		    || ((sd->flags & SD_WAKE_IDLE_FAR)
-			&& !task_hot(p, task_rq(p)->clock, sd))) {
-			for_each_cpu_and(i, sched_domain_span(sd),
-					 &p->cpus_allowed) {
-				if (cpu_active(i) && idle_cpu(i)) {
-					if (i != task_cpu(p)) {
-						schedstat_inc(p,
-						       se.nr_wakeups_idle);
-					}
-					return i;
-				}
-			}
-		} else {
-			break;
-		}
-	}
-	return cpu;
-}
-#else /* !ARCH_HAS_SCHED_WAKE_IDLE*/
-static inline int wake_idle(int cpu, struct task_struct *p)
-{
-	return cpu;
-}
-#endif
-
 #ifdef CONFIG_SMP
 
 #ifdef CONFIG_FAIR_GROUP_SCHED
@@ -1199,25 +1153,34 @@ static inline unsigned long effective_load(struct task_group *tg, int cpu,
 
 #endif
 
-static int
-wake_affine(struct sched_domain *this_sd, struct rq *this_rq,
-	    struct task_struct *p, int prev_cpu, int this_cpu, int sync,
-	    int idx, unsigned long load, unsigned long this_load,
-	    unsigned int imbalance)
+static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
 {
-	struct task_struct *curr = this_rq->curr;
-	struct task_group *tg;
-	unsigned long tl = this_load;
+	struct task_struct *curr = current;
+	unsigned long this_load, load;
+	int idx, this_cpu, prev_cpu;
 	unsigned long tl_per_task;
+	unsigned int imbalance;
+	struct task_group *tg;
 	unsigned long weight;
 	int balanced;
 
-	if (!(this_sd->flags & SD_WAKE_AFFINE) || !sched_feat(AFFINE_WAKEUPS))
-		return 0;
+	idx	  = sd->wake_idx;
+	this_cpu  = smp_processor_id();
+	prev_cpu  = task_cpu(p);
+	load	  = source_load(prev_cpu, idx);
+	this_load = target_load(this_cpu, idx);
 
-	if (sync && (curr->se.avg_overlap > sysctl_sched_migration_cost ||
-			p->se.avg_overlap > sysctl_sched_migration_cost))
-		sync = 0;
+	if (sync) {
+	       if (sched_feat(SYNC_LESS) &&
+		   (curr->se.avg_overlap > sysctl_sched_migration_cost ||
+		    p->se.avg_overlap > sysctl_sched_migration_cost))
+		       sync = 0;
+	} else {
+		if (sched_feat(SYNC_MORE) &&
+		    (curr->se.avg_overlap < sysctl_sched_migration_cost &&
+		     p->se.avg_overlap < sysctl_sched_migration_cost))
+			sync = 1;
+	}
 
 	/*
 	 * If sync wakeup then subtract the (maximum possible)
@@ -1228,14 +1191,26 @@ wake_affine(struct sched_domain *this_sd, struct rq *this_rq,
 		tg = task_group(current);
 		weight = current->se.load.weight;
 
-		tl += effective_load(tg, this_cpu, -weight, -weight);
+		this_load += effective_load(tg, this_cpu, -weight, -weight);
 		load += effective_load(tg, prev_cpu, 0, -weight);
 	}
 
 	tg = task_group(p);
 	weight = p->se.load.weight;
 
-	balanced = 100*(tl + effective_load(tg, this_cpu, weight, weight)) <=
+	imbalance = 100 + (sd->imbalance_pct - 100) / 2;
+
+	/*
+	 * In low-load situations, where prev_cpu is idle and this_cpu is idle
+	 * due to the sync cause above having dropped this_load to 0, we'll
+	 * always have an imbalance, but there's really nothing you can do
+	 * about that, so that's good too.
+	 *
+	 * Otherwise check if either cpus are near enough in load to allow this
+	 * task to be woken on this_cpu.
+	 */
+	balanced = !this_load ||
+		100*(this_load + effective_load(tg, this_cpu, weight, weight)) <=
 		imbalance*(load + effective_load(tg, prev_cpu, 0, weight));
 
 	/*
@@ -1249,14 +1224,15 @@ wake_affine(struct sched_domain *this_sd, struct rq *this_rq,
 	schedstat_inc(p, se.nr_wakeups_affine_attempts);
 	tl_per_task = cpu_avg_load_per_task(this_cpu);
 
-	if (balanced || (tl <= load && tl + target_load(prev_cpu, idx) <=
-			tl_per_task)) {
+	if (balanced ||
+	    (this_load <= load &&
+	     this_load + target_load(prev_cpu, idx) <= tl_per_task)) {
 		/*
 		 * This domain has SD_WAKE_AFFINE and
 		 * p is cache cold in this domain, and
 		 * there is no bad imbalance.
 		 */
-		schedstat_inc(this_sd, ttwu_move_affine);
+		schedstat_inc(sd, ttwu_move_affine);
 		schedstat_inc(p, se.nr_wakeups_affine);
 
 		return 1;
@@ -1264,67 +1240,216 @@ wake_affine(struct sched_domain *this_sd, struct rq *this_rq,
 	return 0;
 }
 
-static int select_task_rq_fair(struct task_struct *p, int sync)
+/*
+ * find_idlest_group finds and returns the least busy CPU group within the
+ * domain.
+ */
+static struct sched_group *
+find_idlest_group(struct sched_domain *sd, struct task_struct *p,
+		  int this_cpu, int load_idx)
 {
-	struct sched_domain *sd, *this_sd = NULL;
-	int prev_cpu, this_cpu, new_cpu;
-	unsigned long load, this_load;
-	struct rq *this_rq;
-	unsigned int imbalance;
-	int idx;
+	struct sched_group *idlest = NULL, *this = NULL, *group = sd->groups;
+	unsigned long min_load = ULONG_MAX, this_load = 0;
+	int imbalance = 100 + (sd->imbalance_pct-100)/2;
 
-	prev_cpu	= task_cpu(p);
-	this_cpu	= smp_processor_id();
-	this_rq		= cpu_rq(this_cpu);
-	new_cpu		= prev_cpu;
+	do {
+		unsigned long load, avg_load;
+		int local_group;
+		int i;
 
-	if (prev_cpu == this_cpu)
-		goto out;
-	/*
-	 * 'this_sd' is the first domain that both
-	 * this_cpu and prev_cpu are present in:
-	 */
-	for_each_domain(this_cpu, sd) {
-		if (cpumask_test_cpu(prev_cpu, sched_domain_span(sd))) {
-			this_sd = sd;
-			break;
+		/* Skip over this group if it has no CPUs allowed */
+		if (!cpumask_intersects(sched_group_cpus(group),
+					&p->cpus_allowed))
+			continue;
+
+		local_group = cpumask_test_cpu(this_cpu,
+					       sched_group_cpus(group));
+
+		/* Tally up the load of all CPUs in the group */
+		avg_load = 0;
+
+		for_each_cpu(i, sched_group_cpus(group)) {
+			/* Bias balancing toward cpus of our domain */
+			if (local_group)
+				load = source_load(i, load_idx);
+			else
+				load = target_load(i, load_idx);
+
+			avg_load += load;
+		}
+
+		/* Adjust by relative CPU power of the group */
+		avg_load = (avg_load * SCHED_LOAD_SCALE) / group->cpu_power;
+
+		if (local_group) {
+			this_load = avg_load;
+			this = group;
+		} else if (avg_load < min_load) {
+			min_load = avg_load;
+			idlest = group;
+		}
+	} while (group = group->next, group != sd->groups);
+
+	if (!idlest || 100*this_load < imbalance*min_load)
+		return NULL;
+	return idlest;
+}
+
+/*
+ * find_idlest_cpu - find the idlest cpu among the cpus in group.
+ */
+static int
+find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
+{
+	unsigned long load, min_load = ULONG_MAX;
+	int idlest = -1;
+	int i;
+
+	/* Traverse only the allowed CPUs */
+	for_each_cpu_and(i, sched_group_cpus(group), &p->cpus_allowed) {
+		load = weighted_cpuload(i);
+
+		if (load < min_load || (load == min_load && i == this_cpu)) {
+			min_load = load;
+			idlest = i;
 		}
 	}
 
-	if (unlikely(!cpumask_test_cpu(this_cpu, &p->cpus_allowed)))
-		goto out;
+	return idlest;
+}
 
-	/*
-	 * Check for affine wakeup and passive balancing possibilities.
-	 */
-	if (!this_sd)
+/*
+ * sched_balance_self: balance the current task (running on cpu) in domains
+ * that have the 'flag' flag set. In practice, this is SD_BALANCE_FORK and
+ * SD_BALANCE_EXEC.
+ *
+ * Balance, ie. select the least loaded group.
+ *
+ * Returns the target CPU number, or the same CPU if no balancing is needed.
+ *
+ * preempt must be disabled.
+ */
+static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flags)
+{
+	struct sched_domain *tmp, *affine_sd = NULL, *sd = NULL;
+	int cpu = smp_processor_id();
+	int prev_cpu = task_cpu(p);
+	int new_cpu = cpu;
+	int want_affine = 0;
+	int want_sd = 1;
+	int sync = wake_flags & WF_SYNC;
+
+	if (sd_flag & SD_BALANCE_WAKE) {
+		if (sched_feat(AFFINE_WAKEUPS) &&
+		    cpumask_test_cpu(cpu, &p->cpus_allowed))
+			want_affine = 1;
+		new_cpu = prev_cpu;
+	}
+
+	rcu_read_lock();
+	for_each_domain(cpu, tmp) {
+		/*
+		 * If power savings logic is enabled for a domain, see if we
+		 * are not overloaded, if so, don't balance wider.
+		 */
+		if (tmp->flags & (SD_POWERSAVINGS_BALANCE|SD_PREFER_LOCAL)) {
+			unsigned long power = 0;
+			unsigned long nr_running = 0;
+			unsigned long capacity;
+			int i;
+
+			for_each_cpu(i, sched_domain_span(tmp)) {
+				power += power_of(i);
+				nr_running += cpu_rq(i)->cfs.nr_running;
+			}
+
+			capacity = DIV_ROUND_CLOSEST(power, SCHED_LOAD_SCALE);
+
+			if (tmp->flags & SD_POWERSAVINGS_BALANCE)
+				nr_running /= 2;
+
+			if (nr_running < capacity)
+				want_sd = 0;
+		}
+
+		if (want_affine && (tmp->flags & SD_WAKE_AFFINE) &&
+		    cpumask_test_cpu(prev_cpu, sched_domain_span(tmp))) {
+
+			affine_sd = tmp;
+			want_affine = 0;
+		}
+
+		if (!want_sd && !want_affine)
+			break;
+
+		if (!(tmp->flags & sd_flag))
+			continue;
+
+		if (want_sd)
+			sd = tmp;
+	}
+
+	if (sched_feat(LB_SHARES_UPDATE)) {
+		/*
+		 * Pick the largest domain to update shares over
+		 */
+		tmp = sd;
+		if (affine_sd && (!tmp ||
+				  cpumask_weight(sched_domain_span(affine_sd)) >
+				  cpumask_weight(sched_domain_span(sd))))
+			tmp = affine_sd;
+
+		if (tmp)
+			update_shares(tmp);
+	}
+
+	if (affine_sd && wake_affine(affine_sd, p, sync)) {
+		new_cpu = cpu;
 		goto out;
+	}
+
+	while (sd) {
+		int load_idx = sd->forkexec_idx;
+		struct sched_group *group;
+		int weight;
 
-	idx = this_sd->wake_idx;
+		if (!(sd->flags & sd_flag)) {
+			sd = sd->child;
+			continue;
+		}
 
-	imbalance = 100 + (this_sd->imbalance_pct - 100) / 2;
+		if (sd_flag & SD_BALANCE_WAKE)
+			load_idx = sd->wake_idx;
 
-	load = source_load(prev_cpu, idx);
-	this_load = target_load(this_cpu, idx);
+		group = find_idlest_group(sd, p, cpu, load_idx);
+		if (!group) {
+			sd = sd->child;
+			continue;
+		}
 
-	if (wake_affine(this_sd, this_rq, p, prev_cpu, this_cpu, sync, idx,
-				     load, this_load, imbalance))
-		return this_cpu;
+		new_cpu = find_idlest_cpu(group, p, cpu);
+		if (new_cpu == -1 || new_cpu == cpu) {
+			/* Now try balancing at a lower domain level of cpu */
+			sd = sd->child;
+			continue;
+		}
 
-	/*
-	 * Start passive balancing when half the imbalance_pct
-	 * limit is reached.
-	 */
-	if (this_sd->flags & SD_WAKE_BALANCE) {
-		if (imbalance*this_load <= 100*load) {
-			schedstat_inc(this_sd, ttwu_move_balance);
-			schedstat_inc(p, se.nr_wakeups_passive);
-			return this_cpu;
+		/* Now try balancing at a lower domain level of new_cpu */
+		cpu = new_cpu;
+		weight = cpumask_weight(sched_domain_span(sd));
+		sd = NULL;
+		for_each_domain(cpu, tmp) {
+			if (weight <= cpumask_weight(sched_domain_span(tmp)))
+				break;
+			if (tmp->flags & sd_flag)
+				sd = tmp;
 		}
+		/* while loop will break here if sd == NULL */
 	}
 
 out:
-	return wake_idle(new_cpu, p);
+	rcu_read_unlock();
+	return new_cpu;
 }
 #endif /* CONFIG_SMP */
 
@@ -1437,11 +1562,12 @@ static void set_next_buddy(struct sched_entity *se)
 /*
  * Preempt the current task with a newly woken task if needed:
  */
-static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int sync)
+static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_flags)
 {
 	struct task_struct *curr = rq->curr;
 	struct sched_entity *se = &curr->se, *pse = &p->se;
 	struct cfs_rq *cfs_rq = task_cfs_rq(curr);
+	int sync = wake_flags & WF_SYNC;
 
 	update_curr(cfs_rq);
 
@@ -1467,7 +1593,8 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int sync)
 	 */
 	if (sched_feat(LAST_BUDDY) && likely(se->on_rq && curr != rq->idle))
 		set_last_buddy(se);
-	set_next_buddy(pse);
+	if (sched_feat(NEXT_BUDDY) && !(wake_flags & WF_FORK))
+		set_next_buddy(pse);
 
 	/*
 	 * We can come here with TIF_NEED_RESCHED already set from new task
@@ -1489,16 +1616,25 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int sync)
 		return;
 	}
 
-	if (!sched_feat(WAKEUP_PREEMPT))
-		return;
-
-	if (sched_feat(WAKEUP_OVERLAP) && (sync ||
-			(se->avg_overlap < sysctl_sched_migration_cost &&
-			 pse->avg_overlap < sysctl_sched_migration_cost))) {
+	if ((sched_feat(WAKEUP_SYNC) && sync) ||
+	    (sched_feat(WAKEUP_OVERLAP) &&
+	     (se->avg_overlap < sysctl_sched_migration_cost &&
+	      pse->avg_overlap < sysctl_sched_migration_cost))) {
 		resched_task(curr);
 		return;
 	}
 
+	if (sched_feat(WAKEUP_RUNNING)) {
+		if (pse->avg_running < se->avg_running) {
+			set_next_buddy(pse);
+			resched_task(curr);
+			return;
+		}
+	}
+
+	if (!sched_feat(WAKEUP_PREEMPT))
+		return;
+
 	find_matching_se(&se, &pse);
 
 	BUG_ON(!pse);
@@ -1521,8 +1657,13 @@ static struct task_struct *pick_next_task_fair(struct rq *rq)
 		/*
 		 * If se was a buddy, clear it so that it will have to earn
 		 * the favour again.
+		 *
+		 * If se was not a buddy, clear the buddies because neither
+		 * was elegible to run, let them earn it again.
+		 *
+		 * IOW. unconditionally clear buddies.
 		 */
-		__clear_buddies(cfs_rq, se);
+		__clear_buddies(cfs_rq, NULL);
 		set_next_entity(cfs_rq, se);
 		cfs_rq = group_cfs_rq(se);
 	} while (cfs_rq);
@@ -1721,6 +1862,8 @@ static void task_new_fair(struct rq *rq, struct task_struct *p)
 	sched_info_queued(p);
 
 	update_curr(cfs_rq);
+	if (curr)
+		se->vruntime = curr->vruntime;
 	place_entity(cfs_rq, se, 1);
 
 	/* 'curr' will be NULL if the child belongs to a different group */
@@ -1796,6 +1939,25 @@ static void moved_group_fair(struct task_struct *p)
 }
 #endif
 
+unsigned int get_rr_interval_fair(struct task_struct *task)
+{
+	struct sched_entity *se = &task->se;
+	unsigned long flags;
+	struct rq *rq;
+	unsigned int rr_interval = 0;
+
+	/*
+	 * Time slice is 0 for SCHED_OTHER tasks that are on an otherwise
+	 * idle runqueue:
+	 */
+	rq = task_rq_lock(task, &flags);
+	if (rq->cfs.load.weight)
+		rr_interval = NS_TO_JIFFIES(sched_slice(&rq->cfs, se));
+	task_rq_unlock(rq, &flags);
+
+	return rr_interval;
+}
+
 /*
  * All the scheduling class methods:
  */
@@ -1824,6 +1986,8 @@ static const struct sched_class fair_sched_class = {
 	.prio_changed		= prio_changed_fair,
 	.switched_to		= switched_to_fair,
 
+	.get_rr_interval	= get_rr_interval_fair,
+
 #ifdef CONFIG_FAIR_GROUP_SCHED
 	.moved_group		= moved_group_fair,
 #endif
diff --git a/kernel/sched_features.h b/kernel/sched_features.h
index 4569bfa..0d94083 100644
--- a/kernel/sched_features.h
+++ b/kernel/sched_features.h
@@ -1,17 +1,123 @@
-SCHED_FEAT(NEW_FAIR_SLEEPERS, 1)
+/*
+ * Disregards a certain amount of sleep time (sched_latency_ns) and
+ * considers the task to be running during that period. This gives it
+ * a service deficit on wakeup, allowing it to run sooner.
+ */
+SCHED_FEAT(FAIR_SLEEPERS, 1)
+
+/*
+ * Only give sleepers 50% of their service deficit. This allows
+ * them to run sooner, but does not allow tons of sleepers to
+ * rip the spread apart.
+ */
+SCHED_FEAT(GENTLE_FAIR_SLEEPERS, 1)
+
+/*
+ * By not normalizing the sleep time, heavy tasks get an effective
+ * longer period, and lighter task an effective shorter period they
+ * are considered running.
+ */
 SCHED_FEAT(NORMALIZED_SLEEPER, 0)
-SCHED_FEAT(ADAPTIVE_GRAN, 1)
-SCHED_FEAT(WAKEUP_PREEMPT, 1)
+
+/*
+ * Place new tasks ahead so that they do not starve already running
+ * tasks
+ */
 SCHED_FEAT(START_DEBIT, 1)
+
+/*
+ * Should wakeups try to preempt running tasks.
+ */
+SCHED_FEAT(WAKEUP_PREEMPT, 1)
+
+/*
+ * Compute wakeup_gran based on task behaviour, clipped to
+ *  [0, sched_wakeup_gran_ns]
+ */
+SCHED_FEAT(ADAPTIVE_GRAN, 1)
+
+/*
+ * When converting the wakeup granularity to virtual time, do it such
+ * that heavier tasks preempting a lighter task have an edge.
+ */
+SCHED_FEAT(ASYM_GRAN, 1)
+
+/*
+ * Always wakeup-preempt SYNC wakeups, see SYNC_WAKEUPS.
+ */
+SCHED_FEAT(WAKEUP_SYNC, 0)
+
+/*
+ * Wakeup preempt based on task behaviour. Tasks that do not overlap
+ * don't get preempted.
+ */
+SCHED_FEAT(WAKEUP_OVERLAP, 0)
+
+/*
+ * Wakeup preemption towards tasks that run short
+ */
+SCHED_FEAT(WAKEUP_RUNNING, 0)
+
+/*
+ * Use the SYNC wakeup hint, pipes and the likes use this to indicate
+ * the remote end is likely to consume the data we just wrote, and
+ * therefore has cache benefit from being placed on the same cpu, see
+ * also AFFINE_WAKEUPS.
+ */
+SCHED_FEAT(SYNC_WAKEUPS, 1)
+
+/*
+ * Based on load and program behaviour, see if it makes sense to place
+ * a newly woken task on the same cpu as the task that woke it --
+ * improve cache locality. Typically used with SYNC wakeups as
+ * generated by pipes and the like, see also SYNC_WAKEUPS.
+ */
 SCHED_FEAT(AFFINE_WAKEUPS, 1)
+
+/*
+ * Weaken SYNC hint based on overlap
+ */
+SCHED_FEAT(SYNC_LESS, 1)
+
+/*
+ * Add SYNC hint based on overlap
+ */
+SCHED_FEAT(SYNC_MORE, 0)
+
+/*
+ * Prefer to schedule the task we woke last (assuming it failed
+ * wakeup-preemption), since its likely going to consume data we
+ * touched, increases cache locality.
+ */
+SCHED_FEAT(NEXT_BUDDY, 0)
+
+/*
+ * Prefer to schedule the task that ran last (when we did
+ * wake-preempt) as that likely will touch the same data, increases
+ * cache locality.
+ */
+SCHED_FEAT(LAST_BUDDY, 1)
+
+/*
+ * Consider buddies to be cache hot, decreases the likelyness of a
+ * cache buddy being migrated away, increases cache locality.
+ */
 SCHED_FEAT(CACHE_HOT_BUDDY, 1)
-SCHED_FEAT(SYNC_WAKEUPS, 1)
+
+/*
+ * Use arch dependent cpu power functions
+ */
+SCHED_FEAT(ARCH_POWER, 0)
+
 SCHED_FEAT(HRTICK, 0)
 SCHED_FEAT(DOUBLE_TICK, 0)
-SCHED_FEAT(ASYM_GRAN, 1)
 SCHED_FEAT(LB_BIAS, 1)
-SCHED_FEAT(LB_WAKEUP_UPDATE, 1)
+SCHED_FEAT(LB_SHARES_UPDATE, 1)
 SCHED_FEAT(ASYM_EFF_LOAD, 1)
-SCHED_FEAT(WAKEUP_OVERLAP, 0)
-SCHED_FEAT(LAST_BUDDY, 1)
+
+/*
+ * Spin-wait on mutex acquisition when the mutex owner is running on
+ * another cpu -- assumes that when the owner is running, it will soon
+ * release the lock. Decreases scheduling overhead.
+ */
 SCHED_FEAT(OWNER_SPIN, 1)
diff --git a/kernel/sched_idletask.c b/kernel/sched_idletask.c
index 499672c..b133a28 100644
--- a/kernel/sched_idletask.c
+++ b/kernel/sched_idletask.c
@@ -6,7 +6,7 @@
  */
 
 #ifdef CONFIG_SMP
-static int select_task_rq_idle(struct task_struct *p, int sync)
+static int select_task_rq_idle(struct task_struct *p, int sd_flag, int flags)
 {
 	return task_cpu(p); /* IDLE tasks as never migrated */
 }
@@ -14,7 +14,7 @@ static int select_task_rq_idle(struct task_struct *p, int sync)
 /*
  * Idle tasks are unconditionally rescheduled:
  */
-static void check_preempt_curr_idle(struct rq *rq, struct task_struct *p, int sync)
+static void check_preempt_curr_idle(struct rq *rq, struct task_struct *p, int flags)
 {
 	resched_task(rq->idle);
 }
@@ -97,6 +97,11 @@ static void prio_changed_idle(struct rq *rq, struct task_struct *p,
 		check_preempt_curr(rq, p, 0);
 }
 
+unsigned int get_rr_interval_idle(struct task_struct *task)
+{
+	return 0;
+}
+
 /*
  * Simple, special scheduling class for the per-CPU idle tasks:
  */
@@ -122,6 +127,8 @@ static const struct sched_class idle_sched_class = {
 	.set_curr_task          = set_curr_task_idle,
 	.task_tick		= task_tick_idle,
 
+	.get_rr_interval	= get_rr_interval_idle,
+
 	.prio_changed		= prio_changed_idle,
 	.switched_to		= switched_to_idle,
 
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 3918e01..a4d790c 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -3,15 +3,18 @@
  * policies)
  */
 
+#ifdef CONFIG_RT_GROUP_SCHED
+
+#define rt_entity_is_task(rt_se) (!(rt_se)->my_q)
+
 static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
 {
+#ifdef CONFIG_SCHED_DEBUG
+	WARN_ON_ONCE(!rt_entity_is_task(rt_se));
+#endif
 	return container_of(rt_se, struct task_struct, rt);
 }
 
-#ifdef CONFIG_RT_GROUP_SCHED
-
-#define rt_entity_is_task(rt_se) (!(rt_se)->my_q)
-
 static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
 {
 	return rt_rq->rq;
@@ -26,6 +29,11 @@ static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se)
 
 #define rt_entity_is_task(rt_se) (1)
 
+static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
+{
+	return container_of(rt_se, struct task_struct, rt);
+}
+
 static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
 {
 	return container_of(rt_rq, struct rq, rt);
@@ -128,6 +136,11 @@ static void dequeue_pushable_task(struct rq *rq, struct task_struct *p)
 	plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks);
 }
 
+static inline int has_pushable_tasks(struct rq *rq)
+{
+	return !plist_head_empty(&rq->rt.pushable_tasks);
+}
+
 #else
 
 static inline void enqueue_pushable_task(struct rq *rq, struct task_struct *p)
@@ -602,6 +615,8 @@ static void update_curr_rt(struct rq *rq)
 	curr->se.exec_start = rq->clock;
 	cpuacct_charge(curr, delta_exec);
 
+	sched_rt_avg_update(rq, delta_exec);
+
 	if (!rt_bandwidth_enabled())
 		return;
 
@@ -874,8 +889,6 @@ static void enqueue_task_rt(struct rq *rq, struct task_struct *p, int wakeup)
 
 	if (!task_current(rq, p) && p->rt.nr_cpus_allowed > 1)
 		enqueue_pushable_task(rq, p);
-
-	inc_cpu_load(rq, p->se.load.weight);
 }
 
 static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
@@ -886,8 +899,6 @@ static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
 	dequeue_rt_entity(rt_se);
 
 	dequeue_pushable_task(rq, p);
-
-	dec_cpu_load(rq, p->se.load.weight);
 }
 
 /*
@@ -927,10 +938,13 @@ static void yield_task_rt(struct rq *rq)
 #ifdef CONFIG_SMP
 static int find_lowest_rq(struct task_struct *task);
 
-static int select_task_rq_rt(struct task_struct *p, int sync)
+static int select_task_rq_rt(struct task_struct *p, int sd_flag, int flags)
 {
 	struct rq *rq = task_rq(p);
 
+	if (sd_flag != SD_BALANCE_WAKE)
+		return smp_processor_id();
+
 	/*
 	 * If the current task is an RT task, then
 	 * try to see if we can wake this RT task up on another
@@ -988,7 +1002,7 @@ static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
 /*
  * Preempt the current task with a newly woken task if needed:
  */
-static void check_preempt_curr_rt(struct rq *rq, struct task_struct *p, int sync)
+static void check_preempt_curr_rt(struct rq *rq, struct task_struct *p, int flags)
 {
 	if (p->prio < rq->curr->prio) {
 		resched_task(rq->curr);
@@ -1064,6 +1078,14 @@ static struct task_struct *pick_next_task_rt(struct rq *rq)
 	if (p)
 		dequeue_pushable_task(rq, p);
 
+#ifdef CONFIG_SMP
+	/*
+	 * We detect this state here so that we can avoid taking the RQ
+	 * lock again later if there is no need to push
+	 */
+	rq->post_schedule = has_pushable_tasks(rq);
+#endif
+
 	return p;
 }
 
@@ -1162,13 +1184,6 @@ static int find_lowest_rq(struct task_struct *task)
 		return -1; /* No targets found */
 
 	/*
-	 * Only consider CPUs that are usable for migration.
-	 * I guess we might want to change cpupri_find() to ignore those
-	 * in the first place.
-	 */
-	cpumask_and(lowest_mask, lowest_mask, cpu_active_mask);
-
-	/*
 	 * At this point we have built a mask of cpus representing the
 	 * lowest priority tasks in the system.  Now we want to elect
 	 * the best one based on our affinity and topology.
@@ -1262,11 +1277,6 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
 	return lowest_rq;
 }
 
-static inline int has_pushable_tasks(struct rq *rq)
-{
-	return !plist_head_empty(&rq->rt.pushable_tasks);
-}
-
 static struct task_struct *pick_next_pushable_task(struct rq *rq)
 {
 	struct task_struct *p;
@@ -1466,23 +1476,9 @@ static void pre_schedule_rt(struct rq *rq, struct task_struct *prev)
 		pull_rt_task(rq);
 }
 
-/*
- * assumes rq->lock is held
- */
-static int needs_post_schedule_rt(struct rq *rq)
-{
-	return has_pushable_tasks(rq);
-}
-
 static void post_schedule_rt(struct rq *rq)
 {
-	/*
-	 * This is only called if needs_post_schedule_rt() indicates that
-	 * we need to push tasks away
-	 */
-	spin_lock_irq(&rq->lock);
 	push_rt_tasks(rq);
-	spin_unlock_irq(&rq->lock);
 }
 
 /*
@@ -1738,6 +1734,17 @@ static void set_curr_task_rt(struct rq *rq)
 	dequeue_pushable_task(rq, p);
 }
 
+unsigned int get_rr_interval_rt(struct task_struct *task)
+{
+	/*
+	 * Time slice is 0 for SCHED_FIFO tasks
+	 */
+	if (task->policy == SCHED_RR)
+		return DEF_TIMESLICE;
+	else
+		return 0;
+}
+
 static const struct sched_class rt_sched_class = {
 	.next			= &fair_sched_class,
 	.enqueue_task		= enqueue_task_rt,
@@ -1758,7 +1765,6 @@ static const struct sched_class rt_sched_class = {
 	.rq_online              = rq_online_rt,
 	.rq_offline             = rq_offline_rt,
 	.pre_schedule		= pre_schedule_rt,
-	.needs_post_schedule	= needs_post_schedule_rt,
 	.post_schedule		= post_schedule_rt,
 	.task_wake_up		= task_wake_up_rt,
 	.switched_from		= switched_from_rt,
@@ -1767,6 +1773,8 @@ static const struct sched_class rt_sched_class = {
 	.set_curr_task          = set_curr_task_rt,
 	.task_tick		= task_tick_rt,
 
+	.get_rr_interval	= get_rr_interval_rt,
+
 	.prio_changed		= prio_changed_rt,
 	.switched_to		= switched_to_rt,
 };
diff --git a/kernel/smp.c b/kernel/smp.c
index 94188b8..fd47a25 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -29,8 +29,7 @@ enum {
 
 struct call_function_data {
 	struct call_single_data	csd;
-	spinlock_t		lock;
-	unsigned int		refs;
+	atomic_t		refs;
 	cpumask_var_t		cpumask;
 };
 
@@ -39,9 +38,7 @@ struct call_single_queue {
 	spinlock_t		lock;
 };
 
-static DEFINE_PER_CPU(struct call_function_data, cfd_data) = {
-	.lock			= __SPIN_LOCK_UNLOCKED(cfd_data.lock),
-};
+static DEFINE_PER_CPU(struct call_function_data, cfd_data);
 
 static int
 hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
@@ -177,6 +174,11 @@ void generic_smp_call_function_interrupt(void)
 	int cpu = get_cpu();
 
 	/*
+	 * Shouldn't receive this interrupt on a cpu that is not yet online.
+	 */
+	WARN_ON_ONCE(!cpu_online(cpu));
+
+	/*
 	 * Ensure entry is visible on call_function_queue after we have
 	 * entered the IPI. See comment in smp_call_function_many.
 	 * If we don't have this, then we may miss an entry on the list
@@ -191,25 +193,18 @@ void generic_smp_call_function_interrupt(void)
 	list_for_each_entry_rcu(data, &call_function.queue, csd.list) {
 		int refs;
 
-		spin_lock(&data->lock);
-		if (!cpumask_test_cpu(cpu, data->cpumask)) {
-			spin_unlock(&data->lock);
+		if (!cpumask_test_and_clear_cpu(cpu, data->cpumask))
 			continue;
-		}
-		cpumask_clear_cpu(cpu, data->cpumask);
-		spin_unlock(&data->lock);
 
 		data->csd.func(data->csd.info);
 
-		spin_lock(&data->lock);
-		WARN_ON(data->refs == 0);
-		refs = --data->refs;
+		refs = atomic_dec_return(&data->refs);
+		WARN_ON(refs < 0);
 		if (!refs) {
 			spin_lock(&call_function.lock);
 			list_del_rcu(&data->csd.list);
 			spin_unlock(&call_function.lock);
 		}
-		spin_unlock(&data->lock);
 
 		if (refs)
 			continue;
@@ -230,6 +225,11 @@ void generic_smp_call_function_single_interrupt(void)
 	unsigned int data_flags;
 	LIST_HEAD(list);
 
+	/*
+	 * Shouldn't receive this interrupt on a cpu that is not yet online.
+	 */
+	WARN_ON_ONCE(!cpu_online(smp_processor_id()));
+
 	spin_lock(&q->lock);
 	list_replace_init(&q->list, &list);
 	spin_unlock(&q->lock);
@@ -285,8 +285,14 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
 	 */
 	this_cpu = get_cpu();
 
-	/* Can deadlock when called with interrupts disabled */
-	WARN_ON_ONCE(irqs_disabled() && !oops_in_progress);
+	/*
+	 * Can deadlock when called with interrupts disabled.
+	 * We allow cpu's that are not yet online though, as no one else can
+	 * send smp call function interrupt to this cpu and as such deadlocks
+	 * can't happen.
+	 */
+	WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled()
+		     && !oops_in_progress);
 
 	if (cpu == this_cpu) {
 		local_irq_save(flags);
@@ -329,8 +335,14 @@ void __smp_call_function_single(int cpu, struct call_single_data *data,
 {
 	csd_lock(data);
 
-	/* Can deadlock when called with interrupts disabled */
-	WARN_ON_ONCE(wait && irqs_disabled() && !oops_in_progress);
+	/*
+	 * Can deadlock when called with interrupts disabled.
+	 * We allow cpu's that are not yet online though, as no one else can
+	 * send smp call function interrupt to this cpu and as such deadlocks
+	 * can't happen.
+	 */
+	WARN_ON_ONCE(cpu_online(smp_processor_id()) && wait && irqs_disabled()
+		     && !oops_in_progress);
 
 	generic_exec_single(cpu, data, wait);
 }
@@ -365,8 +377,14 @@ void smp_call_function_many(const struct cpumask *mask,
 	unsigned long flags;
 	int cpu, next_cpu, this_cpu = smp_processor_id();
 
-	/* Can deadlock when called with interrupts disabled */
-	WARN_ON_ONCE(irqs_disabled() && !oops_in_progress);
+	/*
+	 * Can deadlock when called with interrupts disabled.
+	 * We allow cpu's that are not yet online though, as no one else can
+	 * send smp call function interrupt to this cpu and as such deadlocks
+	 * can't happen.
+	 */
+	WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled()
+		     && !oops_in_progress);
 
 	/* So, what's a CPU they want? Ignoring this one. */
 	cpu = cpumask_first_and(mask, cpu_online_mask);
@@ -391,23 +409,20 @@ void smp_call_function_many(const struct cpumask *mask,
 	data = &__get_cpu_var(cfd_data);
 	csd_lock(&data->csd);
 
-	spin_lock_irqsave(&data->lock, flags);
 	data->csd.func = func;
 	data->csd.info = info;
 	cpumask_and(data->cpumask, mask, cpu_online_mask);
 	cpumask_clear_cpu(this_cpu, data->cpumask);
-	data->refs = cpumask_weight(data->cpumask);
+	atomic_set(&data->refs, cpumask_weight(data->cpumask));
 
-	spin_lock(&call_function.lock);
+	spin_lock_irqsave(&call_function.lock, flags);
 	/*
 	 * Place entry at the _HEAD_ of the list, so that any cpu still
 	 * observing the entry in generic_smp_call_function_interrupt()
 	 * will not miss any other list entries:
 	 */
 	list_add_rcu(&data->csd.list, &call_function.queue);
-	spin_unlock(&call_function.lock);
-
-	spin_unlock_irqrestore(&data->lock, flags);
+	spin_unlock_irqrestore(&call_function.lock, flags);
 
 	/*
 	 * Make the list addition visible before sending the ipi.
diff --git a/kernel/softirq.c b/kernel/softirq.c
index eb5e131..f8749e5 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -57,7 +57,7 @@ static struct softirq_action softirq_vec[NR_SOFTIRQS] __cacheline_aligned_in_smp
 static DEFINE_PER_CPU(struct task_struct *, ksoftirqd);
 
 char *softirq_to_name[NR_SOFTIRQS] = {
-	"HI", "TIMER", "NET_TX", "NET_RX", "BLOCK",
+	"HI", "TIMER", "NET_TX", "NET_RX", "BLOCK", "BLOCK_IOPOLL",
 	"TASKLET", "SCHED", "HRTIMER",	"RCU"
 };
 
@@ -227,7 +227,7 @@ restart:
 				preempt_count() = prev_count;
 			}
 
-			rcu_bh_qsctr_inc(cpu);
+			rcu_bh_qs(cpu);
 		}
 		h++;
 		pending >>= 1;
@@ -721,7 +721,7 @@ static int ksoftirqd(void * __bind_cpu)
 			preempt_enable_no_resched();
 			cond_resched();
 			preempt_disable();
-			rcu_qsctr_inc((long)__bind_cpu);
+			rcu_sched_qs((long)__bind_cpu);
 		}
 		preempt_enable();
 		set_current_state(TASK_INTERRUPTIBLE);
diff --git a/kernel/spinlock.c b/kernel/spinlock.c
index 7932653..5ddab73 100644
--- a/kernel/spinlock.c
+++ b/kernel/spinlock.c
@@ -21,44 +21,29 @@
 #include <linux/debug_locks.h>
 #include <linux/module.h>
 
+#ifndef _spin_trylock
 int __lockfunc _spin_trylock(spinlock_t *lock)
 {
-	preempt_disable();
-	if (_raw_spin_trylock(lock)) {
-		spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
-		return 1;
-	}
-	
-	preempt_enable();
-	return 0;
+	return __spin_trylock(lock);
 }
 EXPORT_SYMBOL(_spin_trylock);
+#endif
 
+#ifndef _read_trylock
 int __lockfunc _read_trylock(rwlock_t *lock)
 {
-	preempt_disable();
-	if (_raw_read_trylock(lock)) {
-		rwlock_acquire_read(&lock->dep_map, 0, 1, _RET_IP_);
-		return 1;
-	}
-
-	preempt_enable();
-	return 0;
+	return __read_trylock(lock);
 }
 EXPORT_SYMBOL(_read_trylock);
+#endif
 
+#ifndef _write_trylock
 int __lockfunc _write_trylock(rwlock_t *lock)
 {
-	preempt_disable();
-	if (_raw_write_trylock(lock)) {
-		rwlock_acquire(&lock->dep_map, 0, 1, _RET_IP_);
-		return 1;
-	}
-
-	preempt_enable();
-	return 0;
+	return __write_trylock(lock);
 }
 EXPORT_SYMBOL(_write_trylock);
+#endif
 
 /*
  * If lockdep is enabled then we use the non-preemption spin-ops
@@ -67,132 +52,101 @@ EXPORT_SYMBOL(_write_trylock);
  */
 #if !defined(CONFIG_GENERIC_LOCKBREAK) || defined(CONFIG_DEBUG_LOCK_ALLOC)
 
+#ifndef _read_lock
 void __lockfunc _read_lock(rwlock_t *lock)
 {
-	preempt_disable();
-	rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
-	LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock);
+	__read_lock(lock);
 }
 EXPORT_SYMBOL(_read_lock);
+#endif
 
+#ifndef _spin_lock_irqsave
 unsigned long __lockfunc _spin_lock_irqsave(spinlock_t *lock)
 {
-	unsigned long flags;
-
-	local_irq_save(flags);
-	preempt_disable();
-	spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
-	/*
-	 * On lockdep we dont want the hand-coded irq-enable of
-	 * _raw_spin_lock_flags() code, because lockdep assumes
-	 * that interrupts are not re-enabled during lock-acquire:
-	 */
-#ifdef CONFIG_LOCKDEP
-	LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock);
-#else
-	_raw_spin_lock_flags(lock, &flags);
-#endif
-	return flags;
+	return __spin_lock_irqsave(lock);
 }
 EXPORT_SYMBOL(_spin_lock_irqsave);
+#endif
 
+#ifndef _spin_lock_irq
 void __lockfunc _spin_lock_irq(spinlock_t *lock)
 {
-	local_irq_disable();
-	preempt_disable();
-	spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
-	LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock);
+	__spin_lock_irq(lock);
 }
 EXPORT_SYMBOL(_spin_lock_irq);
+#endif
 
+#ifndef _spin_lock_bh
 void __lockfunc _spin_lock_bh(spinlock_t *lock)
 {
-	local_bh_disable();
-	preempt_disable();
-	spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
-	LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock);
+	__spin_lock_bh(lock);
 }
 EXPORT_SYMBOL(_spin_lock_bh);
+#endif
 
+#ifndef _read_lock_irqsave
 unsigned long __lockfunc _read_lock_irqsave(rwlock_t *lock)
 {
-	unsigned long flags;
-
-	local_irq_save(flags);
-	preempt_disable();
-	rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
-	LOCK_CONTENDED_FLAGS(lock, _raw_read_trylock, _raw_read_lock,
-			     _raw_read_lock_flags, &flags);
-	return flags;
+	return __read_lock_irqsave(lock);
 }
 EXPORT_SYMBOL(_read_lock_irqsave);
+#endif
 
+#ifndef _read_lock_irq
 void __lockfunc _read_lock_irq(rwlock_t *lock)
 {
-	local_irq_disable();
-	preempt_disable();
-	rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
-	LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock);
+	__read_lock_irq(lock);
 }
 EXPORT_SYMBOL(_read_lock_irq);
+#endif
 
+#ifndef _read_lock_bh
 void __lockfunc _read_lock_bh(rwlock_t *lock)
 {
-	local_bh_disable();
-	preempt_disable();
-	rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
-	LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock);
+	__read_lock_bh(lock);
 }
 EXPORT_SYMBOL(_read_lock_bh);
+#endif
 
+#ifndef _write_lock_irqsave
 unsigned long __lockfunc _write_lock_irqsave(rwlock_t *lock)
 {
-	unsigned long flags;
-
-	local_irq_save(flags);
-	preempt_disable();
-	rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
-	LOCK_CONTENDED_FLAGS(lock, _raw_write_trylock, _raw_write_lock,
-			     _raw_write_lock_flags, &flags);
-	return flags;
+	return __write_lock_irqsave(lock);
 }
 EXPORT_SYMBOL(_write_lock_irqsave);
+#endif
 
+#ifndef _write_lock_irq
 void __lockfunc _write_lock_irq(rwlock_t *lock)
 {
-	local_irq_disable();
-	preempt_disable();
-	rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
-	LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock);
+	__write_lock_irq(lock);
 }
 EXPORT_SYMBOL(_write_lock_irq);
+#endif
 
+#ifndef _write_lock_bh
 void __lockfunc _write_lock_bh(rwlock_t *lock)
 {
-	local_bh_disable();
-	preempt_disable();
-	rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
-	LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock);
+	__write_lock_bh(lock);
 }
 EXPORT_SYMBOL(_write_lock_bh);
+#endif
 
+#ifndef _spin_lock
 void __lockfunc _spin_lock(spinlock_t *lock)
 {
-	preempt_disable();
-	spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
-	LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock);
+	__spin_lock(lock);
 }
-
 EXPORT_SYMBOL(_spin_lock);
+#endif
 
+#ifndef _write_lock
 void __lockfunc _write_lock(rwlock_t *lock)
 {
-	preempt_disable();
-	rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
-	LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock);
+	__write_lock(lock);
 }
-
 EXPORT_SYMBOL(_write_lock);
+#endif
 
 #else /* CONFIG_PREEMPT: */
 
@@ -318,125 +272,109 @@ EXPORT_SYMBOL(_spin_lock_nest_lock);
 
 #endif
 
+#ifndef _spin_unlock
 void __lockfunc _spin_unlock(spinlock_t *lock)
 {
-	spin_release(&lock->dep_map, 1, _RET_IP_);
-	_raw_spin_unlock(lock);
-	preempt_enable();
+	__spin_unlock(lock);
 }
 EXPORT_SYMBOL(_spin_unlock);
+#endif
 
+#ifndef _write_unlock
 void __lockfunc _write_unlock(rwlock_t *lock)
 {
-	rwlock_release(&lock->dep_map, 1, _RET_IP_);
-	_raw_write_unlock(lock);
-	preempt_enable();
+	__write_unlock(lock);
 }
 EXPORT_SYMBOL(_write_unlock);
+#endif
 
+#ifndef _read_unlock
 void __lockfunc _read_unlock(rwlock_t *lock)
 {
-	rwlock_release(&lock->dep_map, 1, _RET_IP_);
-	_raw_read_unlock(lock);
-	preempt_enable();
+	__read_unlock(lock);
 }
 EXPORT_SYMBOL(_read_unlock);
+#endif
 
+#ifndef _spin_unlock_irqrestore
 void __lockfunc _spin_unlock_irqrestore(spinlock_t *lock, unsigned long flags)
 {
-	spin_release(&lock->dep_map, 1, _RET_IP_);
-	_raw_spin_unlock(lock);
-	local_irq_restore(flags);
-	preempt_enable();
+	__spin_unlock_irqrestore(lock, flags);
 }
 EXPORT_SYMBOL(_spin_unlock_irqrestore);
+#endif
 
+#ifndef _spin_unlock_irq
 void __lockfunc _spin_unlock_irq(spinlock_t *lock)
 {
-	spin_release(&lock->dep_map, 1, _RET_IP_);
-	_raw_spin_unlock(lock);
-	local_irq_enable();
-	preempt_enable();
+	__spin_unlock_irq(lock);
 }
 EXPORT_SYMBOL(_spin_unlock_irq);
+#endif
 
+#ifndef _spin_unlock_bh
 void __lockfunc _spin_unlock_bh(spinlock_t *lock)
 {
-	spin_release(&lock->dep_map, 1, _RET_IP_);
-	_raw_spin_unlock(lock);
-	preempt_enable_no_resched();
-	local_bh_enable_ip((unsigned long)__builtin_return_address(0));
+	__spin_unlock_bh(lock);
 }
 EXPORT_SYMBOL(_spin_unlock_bh);
+#endif
 
+#ifndef _read_unlock_irqrestore
 void __lockfunc _read_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
 {
-	rwlock_release(&lock->dep_map, 1, _RET_IP_);
-	_raw_read_unlock(lock);
-	local_irq_restore(flags);
-	preempt_enable();
+	__read_unlock_irqrestore(lock, flags);
 }
 EXPORT_SYMBOL(_read_unlock_irqrestore);
+#endif
 
+#ifndef _read_unlock_irq
 void __lockfunc _read_unlock_irq(rwlock_t *lock)
 {
-	rwlock_release(&lock->dep_map, 1, _RET_IP_);
-	_raw_read_unlock(lock);
-	local_irq_enable();
-	preempt_enable();
+	__read_unlock_irq(lock);
 }
 EXPORT_SYMBOL(_read_unlock_irq);
+#endif
 
+#ifndef _read_unlock_bh
 void __lockfunc _read_unlock_bh(rwlock_t *lock)
 {
-	rwlock_release(&lock->dep_map, 1, _RET_IP_);
-	_raw_read_unlock(lock);
-	preempt_enable_no_resched();
-	local_bh_enable_ip((unsigned long)__builtin_return_address(0));
+	__read_unlock_bh(lock);
 }
 EXPORT_SYMBOL(_read_unlock_bh);
+#endif
 
+#ifndef _write_unlock_irqrestore
 void __lockfunc _write_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
 {
-	rwlock_release(&lock->dep_map, 1, _RET_IP_);
-	_raw_write_unlock(lock);
-	local_irq_restore(flags);
-	preempt_enable();
+	__write_unlock_irqrestore(lock, flags);
 }
 EXPORT_SYMBOL(_write_unlock_irqrestore);
+#endif
 
+#ifndef _write_unlock_irq
 void __lockfunc _write_unlock_irq(rwlock_t *lock)
 {
-	rwlock_release(&lock->dep_map, 1, _RET_IP_);
-	_raw_write_unlock(lock);
-	local_irq_enable();
-	preempt_enable();
+	__write_unlock_irq(lock);
 }
 EXPORT_SYMBOL(_write_unlock_irq);
+#endif
 
+#ifndef _write_unlock_bh
 void __lockfunc _write_unlock_bh(rwlock_t *lock)
 {
-	rwlock_release(&lock->dep_map, 1, _RET_IP_);
-	_raw_write_unlock(lock);
-	preempt_enable_no_resched();
-	local_bh_enable_ip((unsigned long)__builtin_return_address(0));
+	__write_unlock_bh(lock);
 }
 EXPORT_SYMBOL(_write_unlock_bh);
+#endif
 
+#ifndef _spin_trylock_bh
 int __lockfunc _spin_trylock_bh(spinlock_t *lock)
 {
-	local_bh_disable();
-	preempt_disable();
-	if (_raw_spin_trylock(lock)) {
-		spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
-		return 1;
-	}
-
-	preempt_enable_no_resched();
-	local_bh_enable_ip((unsigned long)__builtin_return_address(0));
-	return 0;
+	return __spin_trylock_bh(lock);
 }
 EXPORT_SYMBOL(_spin_trylock_bh);
+#endif
 
 notrace int in_lock_functions(unsigned long addr)
 {
diff --git a/kernel/sys.c b/kernel/sys.c
index b3f1097..ebcb156 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -14,7 +14,7 @@
 #include <linux/prctl.h>
 #include <linux/highuid.h>
 #include <linux/fs.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
 #include <linux/resource.h>
 #include <linux/kernel.h>
 #include <linux/kexec.h>
@@ -1338,6 +1338,7 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
 	unsigned long flags;
 	cputime_t utime, stime;
 	struct task_cputime cputime;
+	unsigned long maxrss = 0;
 
 	memset((char *) r, 0, sizeof *r);
 	utime = stime = cputime_zero;
@@ -1346,6 +1347,7 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
 		utime = task_utime(current);
 		stime = task_stime(current);
 		accumulate_thread_rusage(p, r);
+		maxrss = p->signal->maxrss;
 		goto out;
 	}
 
@@ -1363,6 +1365,7 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
 			r->ru_majflt = p->signal->cmaj_flt;
 			r->ru_inblock = p->signal->cinblock;
 			r->ru_oublock = p->signal->coublock;
+			maxrss = p->signal->cmaxrss;
 
 			if (who == RUSAGE_CHILDREN)
 				break;
@@ -1377,6 +1380,8 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
 			r->ru_majflt += p->signal->maj_flt;
 			r->ru_inblock += p->signal->inblock;
 			r->ru_oublock += p->signal->oublock;
+			if (maxrss < p->signal->maxrss)
+				maxrss = p->signal->maxrss;
 			t = p;
 			do {
 				accumulate_thread_rusage(t, r);
@@ -1392,6 +1397,15 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
 out:
 	cputime_to_timeval(utime, &r->ru_utime);
 	cputime_to_timeval(stime, &r->ru_stime);
+
+	if (who != RUSAGE_CHILDREN) {
+		struct mm_struct *mm = get_task_mm(p);
+		if (mm) {
+			setmax_mm_hiwater_rss(&maxrss, mm);
+			mmput(mm);
+		}
+	}
+	r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */
 }
 
 int getrusage(struct task_struct *p, int who, struct rusage __user *ru)
@@ -1511,11 +1525,11 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
 		case PR_SET_TSC:
 			error = SET_TSC_CTL(arg2);
 			break;
-		case PR_TASK_PERF_COUNTERS_DISABLE:
-			error = perf_counter_task_disable();
+		case PR_TASK_PERF_EVENTS_DISABLE:
+			error = perf_event_task_disable();
 			break;
-		case PR_TASK_PERF_COUNTERS_ENABLE:
-			error = perf_counter_task_enable();
+		case PR_TASK_PERF_EVENTS_ENABLE:
+			error = perf_event_task_enable();
 			break;
 		case PR_GET_TIMERSLACK:
 			error = current->timer_slack_ns;
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 68320f6..515bc23 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -177,4 +177,4 @@ cond_syscall(sys_eventfd);
 cond_syscall(sys_eventfd2);
 
 /* performance counters: */
-cond_syscall(sys_perf_counter_open);
+cond_syscall(sys_perf_event_open);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 58be760..0dfaa47 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -49,9 +49,8 @@
 #include <linux/acpi.h>
 #include <linux/reboot.h>
 #include <linux/ftrace.h>
-#include <linux/security.h>
 #include <linux/slow-work.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
 
 #include <asm/uaccess.h>
 #include <asm/processor.h>
@@ -92,6 +91,9 @@ extern int sysctl_nr_trim_pages;
 #ifdef CONFIG_RCU_TORTURE_TEST
 extern int rcutorture_runnable;
 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
+#ifdef CONFIG_BLOCK
+extern int blk_iopoll_enabled;
+#endif
 
 /* Constants used for minimum and  maximum */
 #ifdef CONFIG_DETECT_SOFTLOCKUP
@@ -104,6 +106,9 @@ static int __maybe_unused one = 1;
 static int __maybe_unused two = 2;
 static unsigned long one_ul = 1;
 static int one_hundred = 100;
+#ifdef CONFIG_PRINTK
+static int ten_thousand = 10000;
+#endif
 
 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
@@ -246,6 +251,14 @@ static int max_wakeup_granularity_ns = NSEC_PER_SEC;	/* 1 second */
 #endif
 
 static struct ctl_table kern_table[] = {
+	{
+		.ctl_name	= CTL_UNNUMBERED,
+		.procname	= "sched_child_runs_first",
+		.data		= &sysctl_sched_child_runs_first,
+		.maxlen		= sizeof(unsigned int),
+		.mode		= 0644,
+		.proc_handler	= &proc_dointvec,
+	},
 #ifdef CONFIG_SCHED_DEBUG
 	{
 		.ctl_name	= CTL_UNNUMBERED,
@@ -300,14 +313,6 @@ static struct ctl_table kern_table[] = {
 	},
 	{
 		.ctl_name	= CTL_UNNUMBERED,
-		.procname	= "sched_child_runs_first",
-		.data		= &sysctl_sched_child_runs_first,
-		.maxlen		= sizeof(unsigned int),
-		.mode		= 0644,
-		.proc_handler	= &proc_dointvec,
-	},
-	{
-		.ctl_name	= CTL_UNNUMBERED,
 		.procname	= "sched_features",
 		.data		= &sysctl_sched_features,
 		.maxlen		= sizeof(unsigned int),
@@ -332,6 +337,14 @@ static struct ctl_table kern_table[] = {
 	},
 	{
 		.ctl_name	= CTL_UNNUMBERED,
+		.procname	= "sched_time_avg",
+		.data		= &sysctl_sched_time_avg,
+		.maxlen		= sizeof(unsigned int),
+		.mode		= 0644,
+		.proc_handler	= &proc_dointvec,
+	},
+	{
+		.ctl_name	= CTL_UNNUMBERED,
 		.procname	= "timer_migration",
 		.data		= &sysctl_timer_migration,
 		.maxlen		= sizeof(unsigned int),
@@ -712,6 +725,17 @@ static struct ctl_table kern_table[] = {
 		.mode		= 0644,
 		.proc_handler	= &proc_dointvec,
 	},
+	{
+		.ctl_name	= CTL_UNNUMBERED,
+		.procname	= "printk_delay",
+		.data		= &printk_delay_msec,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= &proc_dointvec_minmax,
+		.strategy	= &sysctl_intvec,
+		.extra1		= &zero,
+		.extra2		= &ten_thousand,
+	},
 #endif
 	{
 		.ctl_name	= KERN_NGROUPS_MAX,
@@ -954,28 +978,28 @@ static struct ctl_table kern_table[] = {
 		.child		= slow_work_sysctls,
 	},
 #endif
-#ifdef CONFIG_PERF_COUNTERS
+#ifdef CONFIG_PERF_EVENTS
 	{
 		.ctl_name	= CTL_UNNUMBERED,
-		.procname	= "perf_counter_paranoid",
-		.data		= &sysctl_perf_counter_paranoid,
-		.maxlen		= sizeof(sysctl_perf_counter_paranoid),
+		.procname	= "perf_event_paranoid",
+		.data		= &sysctl_perf_event_paranoid,
+		.maxlen		= sizeof(sysctl_perf_event_paranoid),
 		.mode		= 0644,
 		.proc_handler	= &proc_dointvec,
 	},
 	{
 		.ctl_name	= CTL_UNNUMBERED,
-		.procname	= "perf_counter_mlock_kb",
-		.data		= &sysctl_perf_counter_mlock,
-		.maxlen		= sizeof(sysctl_perf_counter_mlock),
+		.procname	= "perf_event_mlock_kb",
+		.data		= &sysctl_perf_event_mlock,
+		.maxlen		= sizeof(sysctl_perf_event_mlock),
 		.mode		= 0644,
 		.proc_handler	= &proc_dointvec,
 	},
 	{
 		.ctl_name	= CTL_UNNUMBERED,
-		.procname	= "perf_counter_max_sample_rate",
-		.data		= &sysctl_perf_counter_sample_rate,
-		.maxlen		= sizeof(sysctl_perf_counter_sample_rate),
+		.procname	= "perf_event_max_sample_rate",
+		.data		= &sysctl_perf_event_sample_rate,
+		.maxlen		= sizeof(sysctl_perf_event_sample_rate),
 		.mode		= 0644,
 		.proc_handler	= &proc_dointvec,
 	},
@@ -990,7 +1014,16 @@ static struct ctl_table kern_table[] = {
 		.proc_handler	= &proc_dointvec,
 	},
 #endif
-
+#ifdef CONFIG_BLOCK
+	{
+		.ctl_name	= CTL_UNNUMBERED,
+		.procname	= "blk_iopoll",
+		.data		= &blk_iopoll_enabled,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= &proc_dointvec,
+	},
+#endif
 /*
  * NOTE: do not add new entries to this table unless you have read
  * Documentation/sysctl/ctl_unnumbered.txt
diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index 888adbc..ea8384d 100644
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -108,7 +108,7 @@ static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp,
 /*
  * Send taskstats data in @skb to listener with nl_pid @pid
  */
-static int send_reply(struct sk_buff *skb, pid_t pid)
+static int send_reply(struct sk_buff *skb, struct genl_info *info)
 {
 	struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb));
 	void *reply = genlmsg_data(genlhdr);
@@ -120,7 +120,7 @@ static int send_reply(struct sk_buff *skb, pid_t pid)
 		return rc;
 	}
 
-	return genlmsg_unicast(skb, pid);
+	return genlmsg_reply(skb, info);
 }
 
 /*
@@ -150,7 +150,7 @@ static void send_cpu_listeners(struct sk_buff *skb,
 			if (!skb_next)
 				break;
 		}
-		rc = genlmsg_unicast(skb_cur, s->pid);
+		rc = genlmsg_unicast(&init_net, skb_cur, s->pid);
 		if (rc == -ECONNREFUSED) {
 			s->valid = 0;
 			delcount++;
@@ -418,7 +418,7 @@ static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
 		goto err;
 	}
 
-	rc = send_reply(rep_skb, info->snd_pid);
+	rc = send_reply(rep_skb, info);
 
 err:
 	fput_light(file, fput_needed);
@@ -487,7 +487,7 @@ free_return_rc:
 	} else
 		goto err;
 
-	return send_reply(rep_skb, info->snd_pid);
+	return send_reply(rep_skb, info);
 err:
 	nlmsg_free(rep_skb);
 	return rc;
diff --git a/kernel/time.c b/kernel/time.c
index 2951194..2e2e469 100644
--- a/kernel/time.c
+++ b/kernel/time.c
@@ -370,13 +370,20 @@ EXPORT_SYMBOL(mktime);
  *	0 <= tv_nsec < NSEC_PER_SEC
  * For negative values only the tv_sec field is negative !
  */
-void set_normalized_timespec(struct timespec *ts, time_t sec, long nsec)
+void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec)
 {
 	while (nsec >= NSEC_PER_SEC) {
+		/*
+		 * The following asm() prevents the compiler from
+		 * optimising this loop into a modulo operation. See
+		 * also __iter_div_u64_rem() in include/linux/time.h
+		 */
+		asm("" : "+rm"(nsec));
 		nsec -= NSEC_PER_SEC;
 		++sec;
 	}
 	while (nsec < 0) {
+		asm("" : "+rm"(nsec));
 		nsec += NSEC_PER_SEC;
 		--sec;
 	}
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 7466cb8..0911334 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -21,7 +21,6 @@
  *
  * TODO WishList:
  *   o Allow clocksource drivers to be unregistered
- *   o get rid of clocksource_jiffies extern
  */
 
 #include <linux/clocksource.h>
@@ -30,6 +29,7 @@
 #include <linux/module.h>
 #include <linux/sched.h> /* for spin_unlock_irq() using preempt_count() m68k */
 #include <linux/tick.h>
+#include <linux/kthread.h>
 
 void timecounter_init(struct timecounter *tc,
 		      const struct cyclecounter *cc,
@@ -107,50 +107,35 @@ u64 timecounter_cyc2time(struct timecounter *tc,
 }
 EXPORT_SYMBOL(timecounter_cyc2time);
 
-/* XXX - Would like a better way for initializing curr_clocksource */
-extern struct clocksource clocksource_jiffies;
-
 /*[Clocksource internal variables]---------
  * curr_clocksource:
- *	currently selected clocksource. Initialized to clocksource_jiffies.
- * next_clocksource:
- *	pending next selected clocksource.
+ *	currently selected clocksource.
  * clocksource_list:
  *	linked list with the registered clocksources
- * clocksource_lock:
- *	protects manipulations to curr_clocksource and next_clocksource
- *	and the clocksource_list
+ * clocksource_mutex:
+ *	protects manipulations to curr_clocksource and the clocksource_list
  * override_name:
  *	Name of the user-specified clocksource.
  */
-static struct clocksource *curr_clocksource = &clocksource_jiffies;
-static struct clocksource *next_clocksource;
-static struct clocksource *clocksource_override;
+static struct clocksource *curr_clocksource;
 static LIST_HEAD(clocksource_list);
-static DEFINE_SPINLOCK(clocksource_lock);
+static DEFINE_MUTEX(clocksource_mutex);
 static char override_name[32];
 static int finished_booting;
 
-/* clocksource_done_booting - Called near the end of core bootup
- *
- * Hack to avoid lots of clocksource churn at boot time.
- * We use fs_initcall because we want this to start before
- * device_initcall but after subsys_initcall.
- */
-static int __init clocksource_done_booting(void)
-{
-	finished_booting = 1;
-	return 0;
-}
-fs_initcall(clocksource_done_booting);
-
 #ifdef CONFIG_CLOCKSOURCE_WATCHDOG
+static void clocksource_watchdog_work(struct work_struct *work);
+
 static LIST_HEAD(watchdog_list);
 static struct clocksource *watchdog;
 static struct timer_list watchdog_timer;
+static DECLARE_WORK(watchdog_work, clocksource_watchdog_work);
 static DEFINE_SPINLOCK(watchdog_lock);
 static cycle_t watchdog_last;
-static unsigned long watchdog_resumed;
+static int watchdog_running;
+
+static int clocksource_watchdog_kthread(void *data);
+static void __clocksource_change_rating(struct clocksource *cs, int rating);
 
 /*
  * Interval: 0.5sec Threshold: 0.0625s
@@ -158,135 +143,249 @@ static unsigned long watchdog_resumed;
 #define WATCHDOG_INTERVAL (HZ >> 1)
 #define WATCHDOG_THRESHOLD (NSEC_PER_SEC >> 4)
 
-static void clocksource_ratewd(struct clocksource *cs, int64_t delta)
+static void clocksource_watchdog_work(struct work_struct *work)
 {
-	if (delta > -WATCHDOG_THRESHOLD && delta < WATCHDOG_THRESHOLD)
-		return;
+	/*
+	 * If kthread_run fails the next watchdog scan over the
+	 * watchdog_list will find the unstable clock again.
+	 */
+	kthread_run(clocksource_watchdog_kthread, NULL, "kwatchdog");
+}
 
+static void __clocksource_unstable(struct clocksource *cs)
+{
+	cs->flags &= ~(CLOCK_SOURCE_VALID_FOR_HRES | CLOCK_SOURCE_WATCHDOG);
+	cs->flags |= CLOCK_SOURCE_UNSTABLE;
+	if (finished_booting)
+		schedule_work(&watchdog_work);
+}
+
+static void clocksource_unstable(struct clocksource *cs, int64_t delta)
+{
 	printk(KERN_WARNING "Clocksource %s unstable (delta = %Ld ns)\n",
 	       cs->name, delta);
-	cs->flags &= ~(CLOCK_SOURCE_VALID_FOR_HRES | CLOCK_SOURCE_WATCHDOG);
-	clocksource_change_rating(cs, 0);
-	list_del(&cs->wd_list);
+	__clocksource_unstable(cs);
+}
+
+/**
+ * clocksource_mark_unstable - mark clocksource unstable via watchdog
+ * @cs:		clocksource to be marked unstable
+ *
+ * This function is called instead of clocksource_change_rating from
+ * cpu hotplug code to avoid a deadlock between the clocksource mutex
+ * and the cpu hotplug mutex. It defers the update of the clocksource
+ * to the watchdog thread.
+ */
+void clocksource_mark_unstable(struct clocksource *cs)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&watchdog_lock, flags);
+	if (!(cs->flags & CLOCK_SOURCE_UNSTABLE)) {
+		if (list_empty(&cs->wd_list))
+			list_add(&cs->wd_list, &watchdog_list);
+		__clocksource_unstable(cs);
+	}
+	spin_unlock_irqrestore(&watchdog_lock, flags);
 }
 
 static void clocksource_watchdog(unsigned long data)
 {
-	struct clocksource *cs, *tmp;
+	struct clocksource *cs;
 	cycle_t csnow, wdnow;
 	int64_t wd_nsec, cs_nsec;
-	int resumed;
+	int next_cpu;
 
 	spin_lock(&watchdog_lock);
-
-	resumed = test_and_clear_bit(0, &watchdog_resumed);
+	if (!watchdog_running)
+		goto out;
 
 	wdnow = watchdog->read(watchdog);
-	wd_nsec = cyc2ns(watchdog, (wdnow - watchdog_last) & watchdog->mask);
+	wd_nsec = clocksource_cyc2ns((wdnow - watchdog_last) & watchdog->mask,
+				     watchdog->mult, watchdog->shift);
 	watchdog_last = wdnow;
 
-	list_for_each_entry_safe(cs, tmp, &watchdog_list, wd_list) {
-		csnow = cs->read(cs);
+	list_for_each_entry(cs, &watchdog_list, wd_list) {
 
-		if (unlikely(resumed)) {
-			cs->wd_last = csnow;
+		/* Clocksource already marked unstable? */
+		if (cs->flags & CLOCK_SOURCE_UNSTABLE) {
+			if (finished_booting)
+				schedule_work(&watchdog_work);
 			continue;
 		}
 
-		/* Initialized ? */
+		csnow = cs->read(cs);
+
+		/* Clocksource initialized ? */
 		if (!(cs->flags & CLOCK_SOURCE_WATCHDOG)) {
-			if ((cs->flags & CLOCK_SOURCE_IS_CONTINUOUS) &&
-			    (watchdog->flags & CLOCK_SOURCE_IS_CONTINUOUS)) {
-				cs->flags |= CLOCK_SOURCE_VALID_FOR_HRES;
-				/*
-				 * We just marked the clocksource as
-				 * highres-capable, notify the rest of the
-				 * system as well so that we transition
-				 * into high-res mode:
-				 */
-				tick_clock_notify();
-			}
 			cs->flags |= CLOCK_SOURCE_WATCHDOG;
 			cs->wd_last = csnow;
-		} else {
-			cs_nsec = cyc2ns(cs, (csnow - cs->wd_last) & cs->mask);
-			cs->wd_last = csnow;
-			/* Check the delta. Might remove from the list ! */
-			clocksource_ratewd(cs, cs_nsec - wd_nsec);
+			continue;
 		}
-	}
 
-	if (!list_empty(&watchdog_list)) {
-		/*
-		 * Cycle through CPUs to check if the CPUs stay
-		 * synchronized to each other.
-		 */
-		int next_cpu = cpumask_next(raw_smp_processor_id(),
-					    cpu_online_mask);
+		/* Check the deviation from the watchdog clocksource. */
+		cs_nsec = clocksource_cyc2ns((csnow - cs->wd_last) &
+					     cs->mask, cs->mult, cs->shift);
+		cs->wd_last = csnow;
+		if (abs(cs_nsec - wd_nsec) > WATCHDOG_THRESHOLD) {
+			clocksource_unstable(cs, cs_nsec - wd_nsec);
+			continue;
+		}
 
-		if (next_cpu >= nr_cpu_ids)
-			next_cpu = cpumask_first(cpu_online_mask);
-		watchdog_timer.expires += WATCHDOG_INTERVAL;
-		add_timer_on(&watchdog_timer, next_cpu);
+		if (!(cs->flags & CLOCK_SOURCE_VALID_FOR_HRES) &&
+		    (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS) &&
+		    (watchdog->flags & CLOCK_SOURCE_IS_CONTINUOUS)) {
+			cs->flags |= CLOCK_SOURCE_VALID_FOR_HRES;
+			/*
+			 * We just marked the clocksource as highres-capable,
+			 * notify the rest of the system as well so that we
+			 * transition into high-res mode:
+			 */
+			tick_clock_notify();
+		}
 	}
+
+	/*
+	 * Cycle through CPUs to check if the CPUs stay synchronized
+	 * to each other.
+	 */
+	next_cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask);
+	if (next_cpu >= nr_cpu_ids)
+		next_cpu = cpumask_first(cpu_online_mask);
+	watchdog_timer.expires += WATCHDOG_INTERVAL;
+	add_timer_on(&watchdog_timer, next_cpu);
+out:
 	spin_unlock(&watchdog_lock);
 }
+
+static inline void clocksource_start_watchdog(void)
+{
+	if (watchdog_running || !watchdog || list_empty(&watchdog_list))
+		return;
+	init_timer(&watchdog_timer);
+	watchdog_timer.function = clocksource_watchdog;
+	watchdog_last = watchdog->read(watchdog);
+	watchdog_timer.expires = jiffies + WATCHDOG_INTERVAL;
+	add_timer_on(&watchdog_timer, cpumask_first(cpu_online_mask));
+	watchdog_running = 1;
+}
+
+static inline void clocksource_stop_watchdog(void)
+{
+	if (!watchdog_running || (watchdog && !list_empty(&watchdog_list)))
+		return;
+	del_timer(&watchdog_timer);
+	watchdog_running = 0;
+}
+
+static inline void clocksource_reset_watchdog(void)
+{
+	struct clocksource *cs;
+
+	list_for_each_entry(cs, &watchdog_list, wd_list)
+		cs->flags &= ~CLOCK_SOURCE_WATCHDOG;
+}
+
 static void clocksource_resume_watchdog(void)
 {
-	set_bit(0, &watchdog_resumed);
+	unsigned long flags;
+
+	spin_lock_irqsave(&watchdog_lock, flags);
+	clocksource_reset_watchdog();
+	spin_unlock_irqrestore(&watchdog_lock, flags);
 }
 
-static void clocksource_check_watchdog(struct clocksource *cs)
+static void clocksource_enqueue_watchdog(struct clocksource *cs)
 {
-	struct clocksource *cse;
 	unsigned long flags;
 
 	spin_lock_irqsave(&watchdog_lock, flags);
 	if (cs->flags & CLOCK_SOURCE_MUST_VERIFY) {
-		int started = !list_empty(&watchdog_list);
-
+		/* cs is a clocksource to be watched. */
 		list_add(&cs->wd_list, &watchdog_list);
-		if (!started && watchdog) {
-			watchdog_last = watchdog->read(watchdog);
-			watchdog_timer.expires = jiffies + WATCHDOG_INTERVAL;
-			add_timer_on(&watchdog_timer,
-				     cpumask_first(cpu_online_mask));
-		}
+		cs->flags &= ~CLOCK_SOURCE_WATCHDOG;
 	} else {
+		/* cs is a watchdog. */
 		if (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS)
 			cs->flags |= CLOCK_SOURCE_VALID_FOR_HRES;
-
+		/* Pick the best watchdog. */
 		if (!watchdog || cs->rating > watchdog->rating) {
-			if (watchdog)
-				del_timer(&watchdog_timer);
 			watchdog = cs;
-			init_timer(&watchdog_timer);
-			watchdog_timer.function = clocksource_watchdog;
-
 			/* Reset watchdog cycles */
-			list_for_each_entry(cse, &watchdog_list, wd_list)
-				cse->flags &= ~CLOCK_SOURCE_WATCHDOG;
-			/* Start if list is not empty */
-			if (!list_empty(&watchdog_list)) {
-				watchdog_last = watchdog->read(watchdog);
-				watchdog_timer.expires =
-					jiffies + WATCHDOG_INTERVAL;
-				add_timer_on(&watchdog_timer,
-					     cpumask_first(cpu_online_mask));
-			}
+			clocksource_reset_watchdog();
+		}
+	}
+	/* Check if the watchdog timer needs to be started. */
+	clocksource_start_watchdog();
+	spin_unlock_irqrestore(&watchdog_lock, flags);
+}
+
+static void clocksource_dequeue_watchdog(struct clocksource *cs)
+{
+	struct clocksource *tmp;
+	unsigned long flags;
+
+	spin_lock_irqsave(&watchdog_lock, flags);
+	if (cs->flags & CLOCK_SOURCE_MUST_VERIFY) {
+		/* cs is a watched clocksource. */
+		list_del_init(&cs->wd_list);
+	} else if (cs == watchdog) {
+		/* Reset watchdog cycles */
+		clocksource_reset_watchdog();
+		/* Current watchdog is removed. Find an alternative. */
+		watchdog = NULL;
+		list_for_each_entry(tmp, &clocksource_list, list) {
+			if (tmp == cs || tmp->flags & CLOCK_SOURCE_MUST_VERIFY)
+				continue;
+			if (!watchdog || tmp->rating > watchdog->rating)
+				watchdog = tmp;
 		}
 	}
+	cs->flags &= ~CLOCK_SOURCE_WATCHDOG;
+	/* Check if the watchdog timer needs to be stopped. */
+	clocksource_stop_watchdog();
 	spin_unlock_irqrestore(&watchdog_lock, flags);
 }
-#else
-static void clocksource_check_watchdog(struct clocksource *cs)
+
+static int clocksource_watchdog_kthread(void *data)
+{
+	struct clocksource *cs, *tmp;
+	unsigned long flags;
+	LIST_HEAD(unstable);
+
+	mutex_lock(&clocksource_mutex);
+	spin_lock_irqsave(&watchdog_lock, flags);
+	list_for_each_entry_safe(cs, tmp, &watchdog_list, wd_list)
+		if (cs->flags & CLOCK_SOURCE_UNSTABLE) {
+			list_del_init(&cs->wd_list);
+			list_add(&cs->wd_list, &unstable);
+		}
+	/* Check if the watchdog timer needs to be stopped. */
+	clocksource_stop_watchdog();
+	spin_unlock_irqrestore(&watchdog_lock, flags);
+
+	/* Needs to be done outside of watchdog lock */
+	list_for_each_entry_safe(cs, tmp, &unstable, wd_list) {
+		list_del_init(&cs->wd_list);
+		__clocksource_change_rating(cs, 0);
+	}
+	mutex_unlock(&clocksource_mutex);
+	return 0;
+}
+
+#else /* CONFIG_CLOCKSOURCE_WATCHDOG */
+
+static void clocksource_enqueue_watchdog(struct clocksource *cs)
 {
 	if (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS)
 		cs->flags |= CLOCK_SOURCE_VALID_FOR_HRES;
 }
 
+static inline void clocksource_dequeue_watchdog(struct clocksource *cs) { }
 static inline void clocksource_resume_watchdog(void) { }
-#endif
+static inline int clocksource_watchdog_kthread(void *data) { return 0; }
+
+#endif /* CONFIG_CLOCKSOURCE_WATCHDOG */
 
 /**
  * clocksource_resume - resume the clocksource(s)
@@ -294,18 +393,16 @@ static inline void clocksource_resume_watchdog(void) { }
 void clocksource_resume(void)
 {
 	struct clocksource *cs;
-	unsigned long flags;
 
-	spin_lock_irqsave(&clocksource_lock, flags);
+	mutex_lock(&clocksource_mutex);
 
-	list_for_each_entry(cs, &clocksource_list, list) {
+	list_for_each_entry(cs, &clocksource_list, list)
 		if (cs->resume)
 			cs->resume();
-	}
 
 	clocksource_resume_watchdog();
 
-	spin_unlock_irqrestore(&clocksource_lock, flags);
+	mutex_unlock(&clocksource_mutex);
 }
 
 /**
@@ -320,75 +417,94 @@ void clocksource_touch_watchdog(void)
 	clocksource_resume_watchdog();
 }
 
+#ifdef CONFIG_GENERIC_TIME
+
 /**
- * clocksource_get_next - Returns the selected clocksource
+ * clocksource_select - Select the best clocksource available
+ *
+ * Private function. Must hold clocksource_mutex when called.
  *
+ * Select the clocksource with the best rating, or the clocksource,
+ * which is selected by userspace override.
  */
-struct clocksource *clocksource_get_next(void)
+static void clocksource_select(void)
 {
-	unsigned long flags;
+	struct clocksource *best, *cs;
 
-	spin_lock_irqsave(&clocksource_lock, flags);
-	if (next_clocksource && finished_booting) {
-		curr_clocksource = next_clocksource;
-		next_clocksource = NULL;
+	if (!finished_booting || list_empty(&clocksource_list))
+		return;
+	/* First clocksource on the list has the best rating. */
+	best = list_first_entry(&clocksource_list, struct clocksource, list);
+	/* Check for the override clocksource. */
+	list_for_each_entry(cs, &clocksource_list, list) {
+		if (strcmp(cs->name, override_name) != 0)
+			continue;
+		/*
+		 * Check to make sure we don't switch to a non-highres
+		 * capable clocksource if the tick code is in oneshot
+		 * mode (highres or nohz)
+		 */
+		if (!(cs->flags & CLOCK_SOURCE_VALID_FOR_HRES) &&
+		    tick_oneshot_mode_active()) {
+			/* Override clocksource cannot be used. */
+			printk(KERN_WARNING "Override clocksource %s is not "
+			       "HRT compatible. Cannot switch while in "
+			       "HRT/NOHZ mode\n", cs->name);
+			override_name[0] = 0;
+		} else
+			/* Override clocksource can be used. */
+			best = cs;
+		break;
+	}
+	if (curr_clocksource != best) {
+		printk(KERN_INFO "Switching to clocksource %s\n", best->name);
+		curr_clocksource = best;
+		timekeeping_notify(curr_clocksource);
 	}
-	spin_unlock_irqrestore(&clocksource_lock, flags);
-
-	return curr_clocksource;
 }
 
-/**
- * select_clocksource - Selects the best registered clocksource.
- *
- * Private function. Must hold clocksource_lock when called.
+#else /* CONFIG_GENERIC_TIME */
+
+static inline void clocksource_select(void) { }
+
+#endif
+
+/*
+ * clocksource_done_booting - Called near the end of core bootup
  *
- * Select the clocksource with the best rating, or the clocksource,
- * which is selected by userspace override.
+ * Hack to avoid lots of clocksource churn at boot time.
+ * We use fs_initcall because we want this to start before
+ * device_initcall but after subsys_initcall.
  */
-static struct clocksource *select_clocksource(void)
+static int __init clocksource_done_booting(void)
 {
-	struct clocksource *next;
-
-	if (list_empty(&clocksource_list))
-		return NULL;
-
-	if (clocksource_override)
-		next = clocksource_override;
-	else
-		next = list_entry(clocksource_list.next, struct clocksource,
-				  list);
+	finished_booting = 1;
 
-	if (next == curr_clocksource)
-		return NULL;
+	/*
+	 * Run the watchdog first to eliminate unstable clock sources
+	 */
+	clocksource_watchdog_kthread(NULL);
 
-	return next;
+	mutex_lock(&clocksource_mutex);
+	clocksource_select();
+	mutex_unlock(&clocksource_mutex);
+	return 0;
 }
+fs_initcall(clocksource_done_booting);
 
 /*
  * Enqueue the clocksource sorted by rating
  */
-static int clocksource_enqueue(struct clocksource *c)
+static void clocksource_enqueue(struct clocksource *cs)
 {
-	struct list_head *tmp, *entry = &clocksource_list;
+	struct list_head *entry = &clocksource_list;
+	struct clocksource *tmp;
 
-	list_for_each(tmp, &clocksource_list) {
-		struct clocksource *cs;
-
-		cs = list_entry(tmp, struct clocksource, list);
-		if (cs == c)
-			return -EBUSY;
+	list_for_each_entry(tmp, &clocksource_list, list)
 		/* Keep track of the place, where to insert */
-		if (cs->rating >= c->rating)
-			entry = tmp;
-	}
-	list_add(&c->list, entry);
-
-	if (strlen(c->name) == strlen(override_name) &&
-	    !strcmp(c->name, override_name))
-		clocksource_override = c;
-
-	return 0;
+		if (tmp->rating >= cs->rating)
+			entry = &tmp->list;
+	list_add(&cs->list, entry);
 }
 
 /**
@@ -397,52 +513,48 @@ static int clocksource_enqueue(struct clocksource *c)
  *
  * Returns -EBUSY if registration fails, zero otherwise.
  */
-int clocksource_register(struct clocksource *c)
+int clocksource_register(struct clocksource *cs)
 {
-	unsigned long flags;
-	int ret;
-
-	spin_lock_irqsave(&clocksource_lock, flags);
-	ret = clocksource_enqueue(c);
-	if (!ret)
-		next_clocksource = select_clocksource();
-	spin_unlock_irqrestore(&clocksource_lock, flags);
-	if (!ret)
-		clocksource_check_watchdog(c);
-	return ret;
+	mutex_lock(&clocksource_mutex);
+	clocksource_enqueue(cs);
+	clocksource_select();
+	clocksource_enqueue_watchdog(cs);
+	mutex_unlock(&clocksource_mutex);
+	return 0;
 }
 EXPORT_SYMBOL(clocksource_register);
 
+static void __clocksource_change_rating(struct clocksource *cs, int rating)
+{
+	list_del(&cs->list);
+	cs->rating = rating;
+	clocksource_enqueue(cs);
+	clocksource_select();
+}
+
 /**
  * clocksource_change_rating - Change the rating of a registered clocksource
- *
  */
 void clocksource_change_rating(struct clocksource *cs, int rating)
 {
-	unsigned long flags;
-
-	spin_lock_irqsave(&clocksource_lock, flags);
-	list_del(&cs->list);
-	cs->rating = rating;
-	clocksource_enqueue(cs);
-	next_clocksource = select_clocksource();
-	spin_unlock_irqrestore(&clocksource_lock, flags);
+	mutex_lock(&clocksource_mutex);
+	__clocksource_change_rating(cs, rating);
+	mutex_unlock(&clocksource_mutex);
 }
+EXPORT_SYMBOL(clocksource_change_rating);
 
 /**
  * clocksource_unregister - remove a registered clocksource
  */
 void clocksource_unregister(struct clocksource *cs)
 {
-	unsigned long flags;
-
-	spin_lock_irqsave(&clocksource_lock, flags);
+	mutex_lock(&clocksource_mutex);
+	clocksource_dequeue_watchdog(cs);
 	list_del(&cs->list);
-	if (clocksource_override == cs)
-		clocksource_override = NULL;
-	next_clocksource = select_clocksource();
-	spin_unlock_irqrestore(&clocksource_lock, flags);
+	clocksource_select();
+	mutex_unlock(&clocksource_mutex);
 }
+EXPORT_SYMBOL(clocksource_unregister);
 
 #ifdef CONFIG_SYSFS
 /**
@@ -458,9 +570,9 @@ sysfs_show_current_clocksources(struct sys_device *dev,
 {
 	ssize_t count = 0;
 
-	spin_lock_irq(&clocksource_lock);
+	mutex_lock(&clocksource_mutex);
 	count = snprintf(buf, PAGE_SIZE, "%s\n", curr_clocksource->name);
-	spin_unlock_irq(&clocksource_lock);
+	mutex_unlock(&clocksource_mutex);
 
 	return count;
 }
@@ -478,9 +590,7 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev,
 					  struct sysdev_attribute *attr,
 					  const char *buf, size_t count)
 {
-	struct clocksource *ovr = NULL;
 	size_t ret = count;
-	int len;
 
 	/* strings from sysfs write are not 0 terminated! */
 	if (count >= sizeof(override_name))
@@ -490,44 +600,14 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev,
 	if (buf[count-1] == '\n')
 		count--;
 
-	spin_lock_irq(&clocksource_lock);
+	mutex_lock(&clocksource_mutex);
 
 	if (count > 0)
 		memcpy(override_name, buf, count);
 	override_name[count] = 0;
+	clocksource_select();
 
-	len = strlen(override_name);
-	if (len) {
-		struct clocksource *cs;
-
-		ovr = clocksource_override;
-		/* try to select it: */
-		list_for_each_entry(cs, &clocksource_list, list) {
-			if (strlen(cs->name) == len &&
-			    !strcmp(cs->name, override_name))
-				ovr = cs;
-		}
-	}
-
-	/*
-	 * Check to make sure we don't switch to a non-highres capable
-	 * clocksource if the tick code is in oneshot mode (highres or nohz)
-	 */
-	if (tick_oneshot_mode_active() && ovr &&
-	    !(ovr->flags & CLOCK_SOURCE_VALID_FOR_HRES)) {
-		printk(KERN_WARNING "%s clocksource is not HRT compatible. "
-			"Cannot switch while in HRT/NOHZ mode\n", ovr->name);
-		ovr = NULL;
-		override_name[0] = 0;
-	}
-
-	/* Reselect, when the override name has changed */
-	if (ovr != clocksource_override) {
-		clocksource_override = ovr;
-		next_clocksource = select_clocksource();
-	}
-
-	spin_unlock_irq(&clocksource_lock);
+	mutex_unlock(&clocksource_mutex);
 
 	return ret;
 }
@@ -547,7 +627,7 @@ sysfs_show_available_clocksources(struct sys_device *dev,
 	struct clocksource *src;
 	ssize_t count = 0;
 
-	spin_lock_irq(&clocksource_lock);
+	mutex_lock(&clocksource_mutex);
 	list_for_each_entry(src, &clocksource_list, list) {
 		/*
 		 * Don't show non-HRES clocksource if the tick code is
@@ -559,7 +639,7 @@ sysfs_show_available_clocksources(struct sys_device *dev,
 				  max((ssize_t)PAGE_SIZE - count, (ssize_t)0),
 				  "%s ", src->name);
 	}
-	spin_unlock_irq(&clocksource_lock);
+	mutex_unlock(&clocksource_mutex);
 
 	count += snprintf(buf + count,
 			  max((ssize_t)PAGE_SIZE - count, (ssize_t)0), "\n");
@@ -614,11 +694,10 @@ device_initcall(init_clocksource_sysfs);
  */
 static int __init boot_override_clocksource(char* str)
 {
-	unsigned long flags;
-	spin_lock_irqsave(&clocksource_lock, flags);
+	mutex_lock(&clocksource_mutex);
 	if (str)
 		strlcpy(override_name, str, sizeof(override_name));
-	spin_unlock_irqrestore(&clocksource_lock, flags);
+	mutex_unlock(&clocksource_mutex);
 	return 1;
 }
 
diff --git a/kernel/time/jiffies.c b/kernel/time/jiffies.c
index c3f6c30..5404a84 100644
--- a/kernel/time/jiffies.c
+++ b/kernel/time/jiffies.c
@@ -61,7 +61,6 @@ struct clocksource clocksource_jiffies = {
 	.read		= jiffies_read,
 	.mask		= 0xffffffff, /*32bits*/
 	.mult		= NSEC_PER_JIFFY << JIFFIES_SHIFT, /* details above */
-	.mult_orig	= NSEC_PER_JIFFY << JIFFIES_SHIFT,
 	.shift		= JIFFIES_SHIFT,
 };
 
@@ -71,3 +70,8 @@ static int __init init_jiffies_clocksource(void)
 }
 
 core_initcall(init_jiffies_clocksource);
+
+struct clocksource * __init __weak clocksource_default_clock(void)
+{
+	return &clocksource_jiffies;
+}
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 7fc6437..4800f93 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -194,8 +194,7 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
 	case TIME_OK:
 		break;
 	case TIME_INS:
-		xtime.tv_sec--;
-		wall_to_monotonic.tv_sec++;
+		timekeeping_leap_insert(-1);
 		time_state = TIME_OOP;
 		printk(KERN_NOTICE
 			"Clock: inserting leap second 23:59:60 UTC\n");
@@ -203,9 +202,8 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
 		res = HRTIMER_RESTART;
 		break;
 	case TIME_DEL:
-		xtime.tv_sec++;
+		timekeeping_leap_insert(1);
 		time_tai--;
-		wall_to_monotonic.tv_sec--;
 		time_state = TIME_WAIT;
 		printk(KERN_NOTICE
 			"Clock: deleting leap second 23:59:59 UTC\n");
@@ -219,7 +217,6 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
 			time_state = TIME_OK;
 		break;
 	}
-	update_vsyscall(&xtime, clock);
 
 	write_sequnlock(&xtime_lock);
 
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index e8c77d9..fb0f46f 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -18,7 +18,117 @@
 #include <linux/jiffies.h>
 #include <linux/time.h>
 #include <linux/tick.h>
+#include <linux/stop_machine.h>
+
+/* Structure holding internal timekeeping values. */
+struct timekeeper {
+	/* Current clocksource used for timekeeping. */
+	struct clocksource *clock;
+	/* The shift value of the current clocksource. */
+	int	shift;
+
+	/* Number of clock cycles in one NTP interval. */
+	cycle_t cycle_interval;
+	/* Number of clock shifted nano seconds in one NTP interval. */
+	u64	xtime_interval;
+	/* Raw nano seconds accumulated per NTP interval. */
+	u32	raw_interval;
+
+	/* Clock shifted nano seconds remainder not stored in xtime.tv_nsec. */
+	u64	xtime_nsec;
+	/* Difference between accumulated time and NTP time in ntp
+	 * shifted nano seconds. */
+	s64	ntp_error;
+	/* Shift conversion between clock shifted nano seconds and
+	 * ntp shifted nano seconds. */
+	int	ntp_error_shift;
+	/* NTP adjusted clock multiplier */
+	u32	mult;
+};
+
+struct timekeeper timekeeper;
+
+/**
+ * timekeeper_setup_internals - Set up internals to use clocksource clock.
+ *
+ * @clock:		Pointer to clocksource.
+ *
+ * Calculates a fixed cycle/nsec interval for a given clocksource/adjustment
+ * pair and interval request.
+ *
+ * Unless you're the timekeeping code, you should not be using this!
+ */
+static void timekeeper_setup_internals(struct clocksource *clock)
+{
+	cycle_t interval;
+	u64 tmp;
+
+	timekeeper.clock = clock;
+	clock->cycle_last = clock->read(clock);
 
+	/* Do the ns -> cycle conversion first, using original mult */
+	tmp = NTP_INTERVAL_LENGTH;
+	tmp <<= clock->shift;
+	tmp += clock->mult/2;
+	do_div(tmp, clock->mult);
+	if (tmp == 0)
+		tmp = 1;
+
+	interval = (cycle_t) tmp;
+	timekeeper.cycle_interval = interval;
+
+	/* Go back from cycles -> shifted ns */
+	timekeeper.xtime_interval = (u64) interval * clock->mult;
+	timekeeper.raw_interval =
+		((u64) interval * clock->mult) >> clock->shift;
+
+	timekeeper.xtime_nsec = 0;
+	timekeeper.shift = clock->shift;
+
+	timekeeper.ntp_error = 0;
+	timekeeper.ntp_error_shift = NTP_SCALE_SHIFT - clock->shift;
+
+	/*
+	 * The timekeeper keeps its own mult values for the currently
+	 * active clocksource. These value will be adjusted via NTP
+	 * to counteract clock drifting.
+	 */
+	timekeeper.mult = clock->mult;
+}
+
+/* Timekeeper helper functions. */
+static inline s64 timekeeping_get_ns(void)
+{
+	cycle_t cycle_now, cycle_delta;
+	struct clocksource *clock;
+
+	/* read clocksource: */
+	clock = timekeeper.clock;
+	cycle_now = clock->read(clock);
+
+	/* calculate the delta since the last update_wall_time: */
+	cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
+
+	/* return delta convert to nanoseconds using ntp adjusted mult. */
+	return clocksource_cyc2ns(cycle_delta, timekeeper.mult,
+				  timekeeper.shift);
+}
+
+static inline s64 timekeeping_get_ns_raw(void)
+{
+	cycle_t cycle_now, cycle_delta;
+	struct clocksource *clock;
+
+	/* read clocksource: */
+	clock = timekeeper.clock;
+	cycle_now = clock->read(clock);
+
+	/* calculate the delta since the last update_wall_time: */
+	cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
+
+	/* return delta convert to nanoseconds using ntp adjusted mult. */
+	return clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
+}
 
 /*
  * This read-write spinlock protects us from races in SMP while
@@ -44,7 +154,12 @@ __cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock);
  */
 struct timespec xtime __attribute__ ((aligned (16)));
 struct timespec wall_to_monotonic __attribute__ ((aligned (16)));
-static unsigned long total_sleep_time;		/* seconds */
+static struct timespec total_sleep_time;
+
+/*
+ * The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock.
+ */
+struct timespec raw_time;
 
 /* flag for if timekeeping is suspended */
 int __read_mostly timekeeping_suspended;
@@ -56,35 +171,44 @@ void update_xtime_cache(u64 nsec)
 	timespec_add_ns(&xtime_cache, nsec);
 }
 
-struct clocksource *clock;
-
+/* must hold xtime_lock */
+void timekeeping_leap_insert(int leapsecond)
+{
+	xtime.tv_sec += leapsecond;
+	wall_to_monotonic.tv_sec -= leapsecond;
+	update_vsyscall(&xtime, timekeeper.clock);
+}
 
 #ifdef CONFIG_GENERIC_TIME
+
 /**
- * clocksource_forward_now - update clock to the current time
+ * timekeeping_forward_now - update clock to the current time
  *
  * Forward the current clock to update its state since the last call to
  * update_wall_time(). This is useful before significant clock changes,
  * as it avoids having to deal with this time offset explicitly.
  */
-static void clocksource_forward_now(void)
+static void timekeeping_forward_now(void)
 {
 	cycle_t cycle_now, cycle_delta;
+	struct clocksource *clock;
 	s64 nsec;
 
-	cycle_now = clocksource_read(clock);
+	clock = timekeeper.clock;
+	cycle_now = clock->read(clock);
 	cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
 	clock->cycle_last = cycle_now;
 
-	nsec = cyc2ns(clock, cycle_delta);
+	nsec = clocksource_cyc2ns(cycle_delta, timekeeper.mult,
+				  timekeeper.shift);
 
 	/* If arch requires, add in gettimeoffset() */
 	nsec += arch_gettimeoffset();
 
 	timespec_add_ns(&xtime, nsec);
 
-	nsec = ((s64)cycle_delta * clock->mult_orig) >> clock->shift;
-	clock->raw_time.tv_nsec += nsec;
+	nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
+	timespec_add_ns(&raw_time, nsec);
 }
 
 /**
@@ -95,7 +219,6 @@ static void clocksource_forward_now(void)
  */
 void getnstimeofday(struct timespec *ts)
 {
-	cycle_t cycle_now, cycle_delta;
 	unsigned long seq;
 	s64 nsecs;
 
@@ -105,15 +228,7 @@ void getnstimeofday(struct timespec *ts)
 		seq = read_seqbegin(&xtime_lock);
 
 		*ts = xtime;
-
-		/* read clocksource: */
-		cycle_now = clocksource_read(clock);
-
-		/* calculate the delta since the last update_wall_time: */
-		cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
-
-		/* convert to nanoseconds: */
-		nsecs = cyc2ns(clock, cycle_delta);
+		nsecs = timekeeping_get_ns();
 
 		/* If arch requires, add in gettimeoffset() */
 		nsecs += arch_gettimeoffset();
@@ -125,6 +240,57 @@ void getnstimeofday(struct timespec *ts)
 
 EXPORT_SYMBOL(getnstimeofday);
 
+ktime_t ktime_get(void)
+{
+	unsigned int seq;
+	s64 secs, nsecs;
+
+	WARN_ON(timekeeping_suspended);
+
+	do {
+		seq = read_seqbegin(&xtime_lock);
+		secs = xtime.tv_sec + wall_to_monotonic.tv_sec;
+		nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec;
+		nsecs += timekeeping_get_ns();
+
+	} while (read_seqretry(&xtime_lock, seq));
+	/*
+	 * Use ktime_set/ktime_add_ns to create a proper ktime on
+	 * 32-bit architectures without CONFIG_KTIME_SCALAR.
+	 */
+	return ktime_add_ns(ktime_set(secs, 0), nsecs);
+}
+EXPORT_SYMBOL_GPL(ktime_get);
+
+/**
+ * ktime_get_ts - get the monotonic clock in timespec format
+ * @ts:		pointer to timespec variable
+ *
+ * The function calculates the monotonic clock from the realtime
+ * clock and the wall_to_monotonic offset and stores the result
+ * in normalized timespec format in the variable pointed to by @ts.
+ */
+void ktime_get_ts(struct timespec *ts)
+{
+	struct timespec tomono;
+	unsigned int seq;
+	s64 nsecs;
+
+	WARN_ON(timekeeping_suspended);
+
+	do {
+		seq = read_seqbegin(&xtime_lock);
+		*ts = xtime;
+		tomono = wall_to_monotonic;
+		nsecs = timekeeping_get_ns();
+
+	} while (read_seqretry(&xtime_lock, seq));
+
+	set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
+				ts->tv_nsec + tomono.tv_nsec + nsecs);
+}
+EXPORT_SYMBOL_GPL(ktime_get_ts);
+
 /**
  * do_gettimeofday - Returns the time of day in a timeval
  * @tv:		pointer to the timeval to be set
@@ -157,7 +323,7 @@ int do_settimeofday(struct timespec *tv)
 
 	write_seqlock_irqsave(&xtime_lock, flags);
 
-	clocksource_forward_now();
+	timekeeping_forward_now();
 
 	ts_delta.tv_sec = tv->tv_sec - xtime.tv_sec;
 	ts_delta.tv_nsec = tv->tv_nsec - xtime.tv_nsec;
@@ -167,10 +333,10 @@ int do_settimeofday(struct timespec *tv)
 
 	update_xtime_cache(0);
 
-	clock->error = 0;
+	timekeeper.ntp_error = 0;
 	ntp_clear();
 
-	update_vsyscall(&xtime, clock);
+	update_vsyscall(&xtime, timekeeper.clock);
 
 	write_sequnlock_irqrestore(&xtime_lock, flags);
 
@@ -187,44 +353,97 @@ EXPORT_SYMBOL(do_settimeofday);
  *
  * Accumulates current time interval and initializes new clocksource
  */
-static void change_clocksource(void)
+static int change_clocksource(void *data)
 {
 	struct clocksource *new, *old;
 
-	new = clocksource_get_next();
+	new = (struct clocksource *) data;
+
+	timekeeping_forward_now();
+	if (!new->enable || new->enable(new) == 0) {
+		old = timekeeper.clock;
+		timekeeper_setup_internals(new);
+		if (old->disable)
+			old->disable(old);
+	}
+	return 0;
+}
 
-	if (clock == new)
+/**
+ * timekeeping_notify - Install a new clock source
+ * @clock:		pointer to the clock source
+ *
+ * This function is called from clocksource.c after a new, better clock
+ * source has been registered. The caller holds the clocksource_mutex.
+ */
+void timekeeping_notify(struct clocksource *clock)
+{
+	if (timekeeper.clock == clock)
 		return;
+	stop_machine(change_clocksource, clock, NULL);
+	tick_clock_notify();
+}
 
-	clocksource_forward_now();
+#else /* GENERIC_TIME */
 
-	if (clocksource_enable(new))
-		return;
+static inline void timekeeping_forward_now(void) { }
 
-	new->raw_time = clock->raw_time;
-	old = clock;
-	clock = new;
-	clocksource_disable(old);
+/**
+ * ktime_get - get the monotonic time in ktime_t format
+ *
+ * returns the time in ktime_t format
+ */
+ktime_t ktime_get(void)
+{
+	struct timespec now;
 
-	clock->cycle_last = 0;
-	clock->cycle_last = clocksource_read(clock);
-	clock->error = 0;
-	clock->xtime_nsec = 0;
-	clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH);
+	ktime_get_ts(&now);
 
-	tick_clock_notify();
+	return timespec_to_ktime(now);
+}
+EXPORT_SYMBOL_GPL(ktime_get);
 
-	/*
-	 * We're holding xtime lock and waking up klogd would deadlock
-	 * us on enqueue.  So no printing!
-	printk(KERN_INFO "Time: %s clocksource has been installed.\n",
-	       clock->name);
-	 */
+/**
+ * ktime_get_ts - get the monotonic clock in timespec format
+ * @ts:		pointer to timespec variable
+ *
+ * The function calculates the monotonic clock from the realtime
+ * clock and the wall_to_monotonic offset and stores the result
+ * in normalized timespec format in the variable pointed to by @ts.
+ */
+void ktime_get_ts(struct timespec *ts)
+{
+	struct timespec tomono;
+	unsigned long seq;
+
+	do {
+		seq = read_seqbegin(&xtime_lock);
+		getnstimeofday(ts);
+		tomono = wall_to_monotonic;
+
+	} while (read_seqretry(&xtime_lock, seq));
+
+	set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
+				ts->tv_nsec + tomono.tv_nsec);
 }
-#else
-static inline void clocksource_forward_now(void) { }
-static inline void change_clocksource(void) { }
-#endif
+EXPORT_SYMBOL_GPL(ktime_get_ts);
+
+#endif /* !GENERIC_TIME */
+
+/**
+ * ktime_get_real - get the real (wall-) time in ktime_t format
+ *
+ * returns the time in ktime_t format
+ */
+ktime_t ktime_get_real(void)
+{
+	struct timespec now;
+
+	getnstimeofday(&now);
+
+	return timespec_to_ktime(now);
+}
+EXPORT_SYMBOL_GPL(ktime_get_real);
 
 /**
  * getrawmonotonic - Returns the raw monotonic time in a timespec
@@ -236,21 +455,11 @@ void getrawmonotonic(struct timespec *ts)
 {
 	unsigned long seq;
 	s64 nsecs;
-	cycle_t cycle_now, cycle_delta;
 
 	do {
 		seq = read_seqbegin(&xtime_lock);
-
-		/* read clocksource: */
-		cycle_now = clocksource_read(clock);
-
-		/* calculate the delta since the last update_wall_time: */
-		cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
-
-		/* convert to nanoseconds: */
-		nsecs = ((s64)cycle_delta * clock->mult_orig) >> clock->shift;
-
-		*ts = clock->raw_time;
+		nsecs = timekeeping_get_ns_raw();
+		*ts = raw_time;
 
 	} while (read_seqretry(&xtime_lock, seq));
 
@@ -270,7 +479,7 @@ int timekeeping_valid_for_hres(void)
 	do {
 		seq = read_seqbegin(&xtime_lock);
 
-		ret = clock->flags & CLOCK_SOURCE_VALID_FOR_HRES;
+		ret = timekeeper.clock->flags & CLOCK_SOURCE_VALID_FOR_HRES;
 
 	} while (read_seqretry(&xtime_lock, seq));
 
@@ -278,17 +487,33 @@ int timekeeping_valid_for_hres(void)
 }
 
 /**
- * read_persistent_clock -  Return time in seconds from the persistent clock.
+ * read_persistent_clock -  Return time from the persistent clock.
  *
  * Weak dummy function for arches that do not yet support it.
- * Returns seconds from epoch using the battery backed persistent clock.
- * Returns zero if unsupported.
+ * Reads the time from the battery backed persistent clock.
+ * Returns a timespec with tv_sec=0 and tv_nsec=0 if unsupported.
  *
  *  XXX - Do be sure to remove it once all arches implement it.
  */
-unsigned long __attribute__((weak)) read_persistent_clock(void)
+void __attribute__((weak)) read_persistent_clock(struct timespec *ts)
 {
-	return 0;
+	ts->tv_sec = 0;
+	ts->tv_nsec = 0;
+}
+
+/**
+ * read_boot_clock -  Return time of the system start.
+ *
+ * Weak dummy function for arches that do not yet support it.
+ * Function to read the exact time the system has been started.
+ * Returns a timespec with tv_sec=0 and tv_nsec=0 if unsupported.
+ *
+ *  XXX - Do be sure to remove it once all arches implement it.
+ */
+void __attribute__((weak)) read_boot_clock(struct timespec *ts)
+{
+	ts->tv_sec = 0;
+	ts->tv_nsec = 0;
 }
 
 /*
@@ -296,29 +521,40 @@ unsigned long __attribute__((weak)) read_persistent_clock(void)
  */
 void __init timekeeping_init(void)
 {
+	struct clocksource *clock;
 	unsigned long flags;
-	unsigned long sec = read_persistent_clock();
+	struct timespec now, boot;
+
+	read_persistent_clock(&now);
+	read_boot_clock(&boot);
 
 	write_seqlock_irqsave(&xtime_lock, flags);
 
 	ntp_init();
 
-	clock = clocksource_get_next();
-	clocksource_enable(clock);
-	clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH);
-	clock->cycle_last = clocksource_read(clock);
-
-	xtime.tv_sec = sec;
-	xtime.tv_nsec = 0;
+	clock = clocksource_default_clock();
+	if (clock->enable)
+		clock->enable(clock);
+	timekeeper_setup_internals(clock);
+
+	xtime.tv_sec = now.tv_sec;
+	xtime.tv_nsec = now.tv_nsec;
+	raw_time.tv_sec = 0;
+	raw_time.tv_nsec = 0;
+	if (boot.tv_sec == 0 && boot.tv_nsec == 0) {
+		boot.tv_sec = xtime.tv_sec;
+		boot.tv_nsec = xtime.tv_nsec;
+	}
 	set_normalized_timespec(&wall_to_monotonic,
-		-xtime.tv_sec, -xtime.tv_nsec);
+				-boot.tv_sec, -boot.tv_nsec);
 	update_xtime_cache(0);
-	total_sleep_time = 0;
+	total_sleep_time.tv_sec = 0;
+	total_sleep_time.tv_nsec = 0;
 	write_sequnlock_irqrestore(&xtime_lock, flags);
 }
 
 /* time in seconds when suspend began */
-static unsigned long timekeeping_suspend_time;
+static struct timespec timekeeping_suspend_time;
 
 /**
  * timekeeping_resume - Resumes the generic timekeeping subsystem.
@@ -331,24 +567,24 @@ static unsigned long timekeeping_suspend_time;
 static int timekeeping_resume(struct sys_device *dev)
 {
 	unsigned long flags;
-	unsigned long now = read_persistent_clock();
+	struct timespec ts;
+
+	read_persistent_clock(&ts);
 
 	clocksource_resume();
 
 	write_seqlock_irqsave(&xtime_lock, flags);
 
-	if (now && (now > timekeeping_suspend_time)) {
-		unsigned long sleep_length = now - timekeeping_suspend_time;
-
-		xtime.tv_sec += sleep_length;
-		wall_to_monotonic.tv_sec -= sleep_length;
-		total_sleep_time += sleep_length;
+	if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) {
+		ts = timespec_sub(ts, timekeeping_suspend_time);
+		xtime = timespec_add_safe(xtime, ts);
+		wall_to_monotonic = timespec_sub(wall_to_monotonic, ts);
+		total_sleep_time = timespec_add_safe(total_sleep_time, ts);
 	}
 	update_xtime_cache(0);
 	/* re-base the last cycle value */
-	clock->cycle_last = 0;
-	clock->cycle_last = clocksource_read(clock);
-	clock->error = 0;
+	timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock);
+	timekeeper.ntp_error = 0;
 	timekeeping_suspended = 0;
 	write_sequnlock_irqrestore(&xtime_lock, flags);
 
@@ -366,10 +602,10 @@ static int timekeeping_suspend(struct sys_device *dev, pm_message_t state)
 {
 	unsigned long flags;
 
-	timekeeping_suspend_time = read_persistent_clock();
+	read_persistent_clock(&timekeeping_suspend_time);
 
 	write_seqlock_irqsave(&xtime_lock, flags);
-	clocksource_forward_now();
+	timekeeping_forward_now();
 	timekeeping_suspended = 1;
 	write_sequnlock_irqrestore(&xtime_lock, flags);
 
@@ -404,7 +640,7 @@ device_initcall(timekeeping_init_device);
  * If the error is already larger, we look ahead even further
  * to compensate for late or lost adjustments.
  */
-static __always_inline int clocksource_bigadjust(s64 error, s64 *interval,
+static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval,
 						 s64 *offset)
 {
 	s64 tick_error, i;
@@ -420,7 +656,7 @@ static __always_inline int clocksource_bigadjust(s64 error, s64 *interval,
 	 * here.  This is tuned so that an error of about 1 msec is adjusted
 	 * within about 1 sec (or 2^20 nsec in 2^SHIFT_HZ ticks).
 	 */
-	error2 = clock->error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ);
+	error2 = timekeeper.ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ);
 	error2 = abs(error2);
 	for (look_ahead = 0; error2 > 0; look_ahead++)
 		error2 >>= 2;
@@ -429,8 +665,8 @@ static __always_inline int clocksource_bigadjust(s64 error, s64 *interval,
 	 * Now calculate the error in (1 << look_ahead) ticks, but first
 	 * remove the single look ahead already included in the error.
 	 */
-	tick_error = tick_length >> (NTP_SCALE_SHIFT - clock->shift + 1);
-	tick_error -= clock->xtime_interval >> 1;
+	tick_error = tick_length >> (timekeeper.ntp_error_shift + 1);
+	tick_error -= timekeeper.xtime_interval >> 1;
 	error = ((error - tick_error) >> look_ahead) + tick_error;
 
 	/* Finally calculate the adjustment shift value.  */
@@ -455,18 +691,18 @@ static __always_inline int clocksource_bigadjust(s64 error, s64 *interval,
  * this is optimized for the most common adjustments of -1,0,1,
  * for other values we can do a bit more work.
  */
-static void clocksource_adjust(s64 offset)
+static void timekeeping_adjust(s64 offset)
 {
-	s64 error, interval = clock->cycle_interval;
+	s64 error, interval = timekeeper.cycle_interval;
 	int adj;
 
-	error = clock->error >> (NTP_SCALE_SHIFT - clock->shift - 1);
+	error = timekeeper.ntp_error >> (timekeeper.ntp_error_shift - 1);
 	if (error > interval) {
 		error >>= 2;
 		if (likely(error <= interval))
 			adj = 1;
 		else
-			adj = clocksource_bigadjust(error, &interval, &offset);
+			adj = timekeeping_bigadjust(error, &interval, &offset);
 	} else if (error < -interval) {
 		error >>= 2;
 		if (likely(error >= -interval)) {
@@ -474,15 +710,15 @@ static void clocksource_adjust(s64 offset)
 			interval = -interval;
 			offset = -offset;
 		} else
-			adj = clocksource_bigadjust(error, &interval, &offset);
+			adj = timekeeping_bigadjust(error, &interval, &offset);
 	} else
 		return;
 
-	clock->mult += adj;
-	clock->xtime_interval += interval;
-	clock->xtime_nsec -= offset;
-	clock->error -= (interval - offset) <<
-			(NTP_SCALE_SHIFT - clock->shift);
+	timekeeper.mult += adj;
+	timekeeper.xtime_interval += interval;
+	timekeeper.xtime_nsec -= offset;
+	timekeeper.ntp_error -= (interval - offset) <<
+				timekeeper.ntp_error_shift;
 }
 
 /**
@@ -492,53 +728,59 @@ static void clocksource_adjust(s64 offset)
  */
 void update_wall_time(void)
 {
+	struct clocksource *clock;
 	cycle_t offset;
+	u64 nsecs;
 
 	/* Make sure we're fully resumed: */
 	if (unlikely(timekeeping_suspended))
 		return;
 
+	clock = timekeeper.clock;
 #ifdef CONFIG_GENERIC_TIME
-	offset = (clocksource_read(clock) - clock->cycle_last) & clock->mask;
+	offset = (clock->read(clock) - clock->cycle_last) & clock->mask;
 #else
-	offset = clock->cycle_interval;
+	offset = timekeeper.cycle_interval;
 #endif
-	clock->xtime_nsec = (s64)xtime.tv_nsec << clock->shift;
+	timekeeper.xtime_nsec = (s64)xtime.tv_nsec << timekeeper.shift;
 
 	/* normally this loop will run just once, however in the
 	 * case of lost or late ticks, it will accumulate correctly.
 	 */
-	while (offset >= clock->cycle_interval) {
+	while (offset >= timekeeper.cycle_interval) {
+		u64 nsecps = (u64)NSEC_PER_SEC << timekeeper.shift;
+
 		/* accumulate one interval */
-		offset -= clock->cycle_interval;
-		clock->cycle_last += clock->cycle_interval;
+		offset -= timekeeper.cycle_interval;
+		clock->cycle_last += timekeeper.cycle_interval;
 
-		clock->xtime_nsec += clock->xtime_interval;
-		if (clock->xtime_nsec >= (u64)NSEC_PER_SEC << clock->shift) {
-			clock->xtime_nsec -= (u64)NSEC_PER_SEC << clock->shift;
+		timekeeper.xtime_nsec += timekeeper.xtime_interval;
+		if (timekeeper.xtime_nsec >= nsecps) {
+			timekeeper.xtime_nsec -= nsecps;
 			xtime.tv_sec++;
 			second_overflow();
 		}
 
-		clock->raw_time.tv_nsec += clock->raw_interval;
-		if (clock->raw_time.tv_nsec >= NSEC_PER_SEC) {
-			clock->raw_time.tv_nsec -= NSEC_PER_SEC;
-			clock->raw_time.tv_sec++;
+		raw_time.tv_nsec += timekeeper.raw_interval;
+		if (raw_time.tv_nsec >= NSEC_PER_SEC) {
+			raw_time.tv_nsec -= NSEC_PER_SEC;
+			raw_time.tv_sec++;
 		}
 
 		/* accumulate error between NTP and clock interval */
-		clock->error += tick_length;
-		clock->error -= clock->xtime_interval << (NTP_SCALE_SHIFT - clock->shift);
+		timekeeper.ntp_error += tick_length;
+		timekeeper.ntp_error -= timekeeper.xtime_interval <<
+					timekeeper.ntp_error_shift;
 	}
 
 	/* correct the clock when NTP error is too big */
-	clocksource_adjust(offset);
+	timekeeping_adjust(offset);
 
 	/*
 	 * Since in the loop above, we accumulate any amount of time
 	 * in xtime_nsec over a second into xtime.tv_sec, its possible for
 	 * xtime_nsec to be fairly small after the loop. Further, if we're
-	 * slightly speeding the clocksource up in clocksource_adjust(),
+	 * slightly speeding the clocksource up in timekeeping_adjust(),
 	 * its possible the required corrective factor to xtime_nsec could
 	 * cause it to underflow.
 	 *
@@ -550,24 +792,25 @@ void update_wall_time(void)
 	 * We'll correct this error next time through this function, when
 	 * xtime_nsec is not as small.
 	 */
-	if (unlikely((s64)clock->xtime_nsec < 0)) {
-		s64 neg = -(s64)clock->xtime_nsec;
-		clock->xtime_nsec = 0;
-		clock->error += neg << (NTP_SCALE_SHIFT - clock->shift);
+	if (unlikely((s64)timekeeper.xtime_nsec < 0)) {
+		s64 neg = -(s64)timekeeper.xtime_nsec;
+		timekeeper.xtime_nsec = 0;
+		timekeeper.ntp_error += neg << timekeeper.ntp_error_shift;
 	}
 
 	/* store full nanoseconds into xtime after rounding it up and
 	 * add the remainder to the error difference.
 	 */
-	xtime.tv_nsec = ((s64)clock->xtime_nsec >> clock->shift) + 1;
-	clock->xtime_nsec -= (s64)xtime.tv_nsec << clock->shift;
-	clock->error += clock->xtime_nsec << (NTP_SCALE_SHIFT - clock->shift);
+	xtime.tv_nsec =	((s64) timekeeper.xtime_nsec >> timekeeper.shift) + 1;
+	timekeeper.xtime_nsec -= (s64) xtime.tv_nsec << timekeeper.shift;
+	timekeeper.ntp_error +=	timekeeper.xtime_nsec <<
+				timekeeper.ntp_error_shift;
 
-	update_xtime_cache(cyc2ns(clock, offset));
+	nsecs = clocksource_cyc2ns(offset, timekeeper.mult, timekeeper.shift);
+	update_xtime_cache(nsecs);
 
 	/* check to see if there is a new clocksource to use */
-	change_clocksource();
-	update_vsyscall(&xtime, clock);
+	update_vsyscall(&xtime, timekeeper.clock);
 }
 
 /**
@@ -583,9 +826,12 @@ void update_wall_time(void)
  */
 void getboottime(struct timespec *ts)
 {
-	set_normalized_timespec(ts,
-		- (wall_to_monotonic.tv_sec + total_sleep_time),
-		- wall_to_monotonic.tv_nsec);
+	struct timespec boottime = {
+		.tv_sec = wall_to_monotonic.tv_sec + total_sleep_time.tv_sec,
+		.tv_nsec = wall_to_monotonic.tv_nsec + total_sleep_time.tv_nsec
+	};
+
+	set_normalized_timespec(ts, -boottime.tv_sec, -boottime.tv_nsec);
 }
 
 /**
@@ -594,7 +840,7 @@ void getboottime(struct timespec *ts)
  */
 void monotonic_to_bootbased(struct timespec *ts)
 {
-	ts->tv_sec += total_sleep_time;
+	*ts = timespec_add_safe(*ts, total_sleep_time);
 }
 
 unsigned long get_seconds(void)
@@ -603,6 +849,10 @@ unsigned long get_seconds(void)
 }
 EXPORT_SYMBOL(get_seconds);
 
+struct timespec __current_kernel_time(void)
+{
+	return xtime_cache;
+}
 
 struct timespec current_kernel_time(void)
 {
@@ -618,3 +868,20 @@ struct timespec current_kernel_time(void)
 	return now;
 }
 EXPORT_SYMBOL(current_kernel_time);
+
+struct timespec get_monotonic_coarse(void)
+{
+	struct timespec now, mono;
+	unsigned long seq;
+
+	do {
+		seq = read_seqbegin(&xtime_lock);
+
+		now = xtime_cache;
+		mono = wall_to_monotonic;
+	} while (read_seqretry(&xtime_lock, seq));
+
+	set_normalized_timespec(&now, now.tv_sec + mono.tv_sec,
+				now.tv_nsec + mono.tv_nsec);
+	return now;
+}
diff --git a/kernel/timer.c b/kernel/timer.c
index a7f07d5..5db5a8d 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -37,7 +37,7 @@
 #include <linux/delay.h>
 #include <linux/tick.h>
 #include <linux/kallsyms.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
 #include <linux/sched.h>
 
 #include <asm/uaccess.h>
@@ -46,6 +46,9 @@
 #include <asm/timex.h>
 #include <asm/io.h>
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/timer.h>
+
 u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;
 
 EXPORT_SYMBOL(jiffies_64);
@@ -72,6 +75,7 @@ struct tvec_base {
 	spinlock_t lock;
 	struct timer_list *running_timer;
 	unsigned long timer_jiffies;
+	unsigned long next_timer;
 	struct tvec_root tv1;
 	struct tvec tv2;
 	struct tvec tv3;
@@ -520,6 +524,25 @@ static inline void debug_timer_activate(struct timer_list *timer) { }
 static inline void debug_timer_deactivate(struct timer_list *timer) { }
 #endif
 
+static inline void debug_init(struct timer_list *timer)
+{
+	debug_timer_init(timer);
+	trace_timer_init(timer);
+}
+
+static inline void
+debug_activate(struct timer_list *timer, unsigned long expires)
+{
+	debug_timer_activate(timer);
+	trace_timer_start(timer, expires);
+}
+
+static inline void debug_deactivate(struct timer_list *timer)
+{
+	debug_timer_deactivate(timer);
+	trace_timer_cancel(timer);
+}
+
 static void __init_timer(struct timer_list *timer,
 			 const char *name,
 			 struct lock_class_key *key)
@@ -548,7 +571,7 @@ void init_timer_key(struct timer_list *timer,
 		    const char *name,
 		    struct lock_class_key *key)
 {
-	debug_timer_init(timer);
+	debug_init(timer);
 	__init_timer(timer, name, key);
 }
 EXPORT_SYMBOL(init_timer_key);
@@ -567,7 +590,7 @@ static inline void detach_timer(struct timer_list *timer,
 {
 	struct list_head *entry = &timer->entry;
 
-	debug_timer_deactivate(timer);
+	debug_deactivate(timer);
 
 	__list_del(entry->prev, entry->next);
 	if (clear_pending)
@@ -622,13 +645,16 @@ __mod_timer(struct timer_list *timer, unsigned long expires,
 
 	if (timer_pending(timer)) {
 		detach_timer(timer, 0);
+		if (timer->expires == base->next_timer &&
+		    !tbase_get_deferrable(timer->base))
+			base->next_timer = base->timer_jiffies;
 		ret = 1;
 	} else {
 		if (pending_only)
 			goto out_unlock;
 	}
 
-	debug_timer_activate(timer);
+	debug_activate(timer, expires);
 
 	new_base = __get_cpu_var(tvec_bases);
 
@@ -663,6 +689,9 @@ __mod_timer(struct timer_list *timer, unsigned long expires,
 	}
 
 	timer->expires = expires;
+	if (time_before(timer->expires, base->next_timer) &&
+	    !tbase_get_deferrable(timer->base))
+		base->next_timer = timer->expires;
 	internal_add_timer(base, timer);
 
 out_unlock:
@@ -780,7 +809,10 @@ void add_timer_on(struct timer_list *timer, int cpu)
 	BUG_ON(timer_pending(timer) || !timer->function);
 	spin_lock_irqsave(&base->lock, flags);
 	timer_set_base(timer, base);
-	debug_timer_activate(timer);
+	debug_activate(timer, timer->expires);
+	if (time_before(timer->expires, base->next_timer) &&
+	    !tbase_get_deferrable(timer->base))
+		base->next_timer = timer->expires;
 	internal_add_timer(base, timer);
 	/*
 	 * Check whether the other CPU is idle and needs to be
@@ -817,6 +849,9 @@ int del_timer(struct timer_list *timer)
 		base = lock_timer_base(timer, &flags);
 		if (timer_pending(timer)) {
 			detach_timer(timer, 1);
+			if (timer->expires == base->next_timer &&
+			    !tbase_get_deferrable(timer->base))
+				base->next_timer = base->timer_jiffies;
 			ret = 1;
 		}
 		spin_unlock_irqrestore(&base->lock, flags);
@@ -850,6 +885,9 @@ int try_to_del_timer_sync(struct timer_list *timer)
 	ret = 0;
 	if (timer_pending(timer)) {
 		detach_timer(timer, 1);
+		if (timer->expires == base->next_timer &&
+		    !tbase_get_deferrable(timer->base))
+			base->next_timer = base->timer_jiffies;
 		ret = 1;
 	}
 out:
@@ -984,7 +1022,9 @@ static inline void __run_timers(struct tvec_base *base)
 				 */
 				lock_map_acquire(&lockdep_map);
 
+				trace_timer_expire_entry(timer);
 				fn(data);
+				trace_timer_expire_exit(timer);
 
 				lock_map_release(&lockdep_map);
 
@@ -1007,8 +1047,8 @@ static inline void __run_timers(struct tvec_base *base)
 #ifdef CONFIG_NO_HZ
 /*
  * Find out when the next timer event is due to happen. This
- * is used on S/390 to stop all activity when a cpus is idle.
- * This functions needs to be called disabled.
+ * is used on S/390 to stop all activity when a CPU is idle.
+ * This function needs to be called with interrupts disabled.
  */
 static unsigned long __next_timer_interrupt(struct tvec_base *base)
 {
@@ -1134,7 +1174,9 @@ unsigned long get_next_timer_interrupt(unsigned long now)
 	unsigned long expires;
 
 	spin_lock(&base->lock);
-	expires = __next_timer_interrupt(base);
+	if (time_before_eq(base->next_timer, base->timer_jiffies))
+		base->next_timer = __next_timer_interrupt(base);
+	expires = base->next_timer;
 	spin_unlock(&base->lock);
 
 	if (time_before_eq(expires, now))
@@ -1156,8 +1198,7 @@ void update_process_times(int user_tick)
 	/* Note: this timer irq context must be accounted for as well. */
 	account_process_tick(p, user_tick);
 	run_local_timers();
-	if (rcu_pending(cpu))
-		rcu_check_callbacks(cpu, user_tick);
+	rcu_check_callbacks(cpu, user_tick);
 	printk_tick();
 	scheduler_tick();
 	run_posix_cpu_timers(p);
@@ -1170,7 +1211,7 @@ static void run_timer_softirq(struct softirq_action *h)
 {
 	struct tvec_base *base = __get_cpu_var(tvec_bases);
 
-	perf_counter_do_pending();
+	perf_event_do_pending();
 
 	hrtimer_run_pending();
 
@@ -1523,6 +1564,7 @@ static int __cpuinit init_timers_cpu(int cpu)
 		INIT_LIST_HEAD(base->tv1.vec + j);
 
 	base->timer_jiffies = jiffies;
+	base->next_timer = base->timer_jiffies;
 	return 0;
 }
 
@@ -1535,6 +1577,9 @@ static void migrate_timer_list(struct tvec_base *new_base, struct list_head *hea
 		timer = list_first_entry(head, struct timer_list, entry);
 		detach_timer(timer, 0);
 		timer_set_base(timer, new_base);
+		if (time_before(timer->expires, new_base->next_timer) &&
+		    !tbase_get_deferrable(timer->base))
+			new_base->next_timer = timer->expires;
 		internal_add_timer(new_base, timer);
 	}
 }
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index e78dcbd..15372a9 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -11,12 +11,18 @@ config NOP_TRACER
 
 config HAVE_FTRACE_NMI_ENTER
 	bool
+	help
+	  See Documentation/trace/ftrace-implementation.txt
 
 config HAVE_FUNCTION_TRACER
 	bool
+	help
+	  See Documentation/trace/ftrace-implementation.txt
 
 config HAVE_FUNCTION_GRAPH_TRACER
 	bool
+	help
+	  See Documentation/trace/ftrace-implementation.txt
 
 config HAVE_FUNCTION_GRAPH_FP_TEST
 	bool
@@ -28,21 +34,25 @@ config HAVE_FUNCTION_GRAPH_FP_TEST
 config HAVE_FUNCTION_TRACE_MCOUNT_TEST
 	bool
 	help
-	 This gets selected when the arch tests the function_trace_stop
-	 variable at the mcount call site. Otherwise, this variable
-	 is tested by the called function.
+	  See Documentation/trace/ftrace-implementation.txt
 
 config HAVE_DYNAMIC_FTRACE
 	bool
+	help
+	  See Documentation/trace/ftrace-implementation.txt
 
 config HAVE_FTRACE_MCOUNT_RECORD
 	bool
+	help
+	  See Documentation/trace/ftrace-implementation.txt
 
 config HAVE_HW_BRANCH_TRACER
 	bool
 
 config HAVE_SYSCALL_TRACEPOINTS
 	bool
+	help
+	  See Documentation/trace/ftrace-implementation.txt
 
 config TRACER_MAX_TRACE
 	bool
@@ -73,7 +83,7 @@ config RING_BUFFER_ALLOW_SWAP
 # This allows those options to appear when no other tracer is selected. But the
 # options do not appear when something else selects it. We need the two options
 # GENERIC_TRACER and TRACING to avoid circular dependencies to accomplish the
-# hidding of the automatic options options.
+# hidding of the automatic options.
 
 config TRACING
 	bool
@@ -481,6 +491,18 @@ config FTRACE_STARTUP_TEST
 	  functioning properly. It will do tests on all the configured
 	  tracers of ftrace.
 
+config EVENT_TRACE_TEST_SYSCALLS
+	bool "Run selftest on syscall events"
+	depends on FTRACE_STARTUP_TEST
+	help
+	 This option will also enable testing every syscall event.
+	 It only enables the event and disables it and runs various loads
+	 with the event enabled. This adds a bit more time for kernel boot
+	 up since it runs this on every system call defined.
+
+	 TBD - enable a way to actually call the syscalls as we test their
+	       events
+
 config MMIOTRACE
 	bool "Memory mapped IO tracing"
 	depends on HAVE_MMIOTRACE_SUPPORT && PCI
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index 7c00a1e..c8cb75d 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -42,7 +42,6 @@ obj-$(CONFIG_BOOT_TRACER) += trace_boot.o
 obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += trace_functions_graph.o
 obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o
 obj-$(CONFIG_HW_BRANCH_TRACER) += trace_hw_branches.o
-obj-$(CONFIG_POWER_TRACER) += trace_power.o
 obj-$(CONFIG_KMEMTRACE) += kmemtrace.o
 obj-$(CONFIG_WORKQUEUE_TRACER) += trace_workqueue.o
 obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o
@@ -55,5 +54,6 @@ obj-$(CONFIG_FTRACE_SYSCALLS) += trace_syscalls.o
 obj-$(CONFIG_EVENT_PROFILE) += trace_event_profile.o
 obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o
 obj-$(CONFIG_KPROBE_TRACER) += trace_kprobe.o
+obj-$(CONFIG_EVENT_TRACING) += power-traces.o
 
 libftrace-y := ftrace.o
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8c804e2..23df7771 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1323,11 +1323,10 @@ static int __init ftrace_dyn_table_alloc(unsigned long num_to_init)
 
 enum {
 	FTRACE_ITER_FILTER	= (1 << 0),
-	FTRACE_ITER_CONT	= (1 << 1),
-	FTRACE_ITER_NOTRACE	= (1 << 2),
-	FTRACE_ITER_FAILURES	= (1 << 3),
-	FTRACE_ITER_PRINTALL	= (1 << 4),
-	FTRACE_ITER_HASH	= (1 << 5),
+	FTRACE_ITER_NOTRACE	= (1 << 1),
+	FTRACE_ITER_FAILURES	= (1 << 2),
+	FTRACE_ITER_PRINTALL	= (1 << 3),
+	FTRACE_ITER_HASH	= (1 << 4),
 };
 
 #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
@@ -1337,8 +1336,7 @@ struct ftrace_iterator {
 	int			hidx;
 	int			idx;
 	unsigned		flags;
-	unsigned char		buffer[FTRACE_BUFF_MAX+1];
-	unsigned		buffer_idx;
+	struct trace_parser	parser;
 };
 
 static void *
@@ -1407,7 +1405,7 @@ static int t_hash_show(struct seq_file *m, void *v)
 	if (rec->ops->print)
 		return rec->ops->print(m, rec->ip, rec->ops, rec->data);
 
-	seq_printf(m, "%pf:%pf", (void *)rec->ip, (void *)rec->ops->func);
+	seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func);
 
 	if (rec->data)
 		seq_printf(m, ":%p", rec->data);
@@ -1517,12 +1515,12 @@ static int t_show(struct seq_file *m, void *v)
 	if (!rec)
 		return 0;
 
-	seq_printf(m, "%pf\n", (void *)rec->ip);
+	seq_printf(m, "%ps\n", (void *)rec->ip);
 
 	return 0;
 }
 
-static struct seq_operations show_ftrace_seq_ops = {
+static const struct seq_operations show_ftrace_seq_ops = {
 	.start = t_start,
 	.next = t_next,
 	.stop = t_stop,
@@ -1604,6 +1602,11 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
 	if (!iter)
 		return -ENOMEM;
 
+	if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) {
+		kfree(iter);
+		return -ENOMEM;
+	}
+
 	mutex_lock(&ftrace_regex_lock);
 	if ((file->f_mode & FMODE_WRITE) &&
 	    (file->f_flags & O_TRUNC))
@@ -2059,9 +2062,9 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 	int i, len = 0;
 	char *search;
 
-	if (glob && (strcmp(glob, "*") || !strlen(glob)))
+	if (glob && (strcmp(glob, "*") == 0 || !strlen(glob)))
 		glob = NULL;
-	else {
+	else if (glob) {
 		int not;
 
 		type = ftrace_setup_glob(glob, strlen(glob), &search, &not);
@@ -2196,9 +2199,8 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
 		   size_t cnt, loff_t *ppos, int enable)
 {
 	struct ftrace_iterator *iter;
-	char ch;
-	size_t read = 0;
-	ssize_t ret;
+	struct trace_parser *parser;
+	ssize_t ret, read;
 
 	if (!cnt || cnt < 0)
 		return 0;
@@ -2211,72 +2213,23 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
 	} else
 		iter = file->private_data;
 
-	if (!*ppos) {
-		iter->flags &= ~FTRACE_ITER_CONT;
-		iter->buffer_idx = 0;
-	}
+	parser = &iter->parser;
+	read = trace_get_user(parser, ubuf, cnt, ppos);
 
-	ret = get_user(ch, ubuf++);
-	if (ret)
-		goto out;
-	read++;
-	cnt--;
-
-	/*
-	 * If the parser haven't finished with the last write,
-	 * continue reading the user input without skipping spaces.
-	 */
-	if (!(iter->flags & FTRACE_ITER_CONT)) {
-		/* skip white space */
-		while (cnt && isspace(ch)) {
-			ret = get_user(ch, ubuf++);
-			if (ret)
-				goto out;
-			read++;
-			cnt--;
-		}
-
-		/* only spaces were written */
-		if (isspace(ch)) {
-			*ppos += read;
-			ret = read;
-			goto out;
-		}
-
-		iter->buffer_idx = 0;
-	}
-
-	while (cnt && !isspace(ch)) {
-		if (iter->buffer_idx < FTRACE_BUFF_MAX)
-			iter->buffer[iter->buffer_idx++] = ch;
-		else {
-			ret = -EINVAL;
-			goto out;
-		}
-		ret = get_user(ch, ubuf++);
+	if (trace_parser_loaded(parser) &&
+	    !trace_parser_cont(parser)) {
+		ret = ftrace_process_regex(parser->buffer,
+					   parser->idx, enable);
 		if (ret)
 			goto out;
-		read++;
-		cnt--;
-	}
 
-	if (isspace(ch)) {
-		iter->buffer[iter->buffer_idx] = 0;
-		ret = ftrace_process_regex(iter->buffer,
-					   iter->buffer_idx, enable);
-		if (ret)
-			goto out;
-		iter->buffer_idx = 0;
-	} else {
-		iter->flags |= FTRACE_ITER_CONT;
-		iter->buffer[iter->buffer_idx++] = ch;
+		trace_parser_clear(parser);
 	}
 
-	*ppos += read;
 	ret = read;
- out:
-	mutex_unlock(&ftrace_regex_lock);
 
+	mutex_unlock(&ftrace_regex_lock);
+out:
 	return ret;
 }
 
@@ -2381,6 +2334,7 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
 {
 	struct seq_file *m = (struct seq_file *)file->private_data;
 	struct ftrace_iterator *iter;
+	struct trace_parser *parser;
 
 	mutex_lock(&ftrace_regex_lock);
 	if (file->f_mode & FMODE_READ) {
@@ -2390,9 +2344,10 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
 	} else
 		iter = file->private_data;
 
-	if (iter->buffer_idx) {
-		iter->buffer[iter->buffer_idx] = 0;
-		ftrace_match_records(iter->buffer, iter->buffer_idx, enable);
+	parser = &iter->parser;
+	if (trace_parser_loaded(parser)) {
+		parser->buffer[parser->idx] = 0;
+		ftrace_match_records(parser->buffer, parser->idx, enable);
 	}
 
 	mutex_lock(&ftrace_lock);
@@ -2400,7 +2355,9 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
 		ftrace_run_update_code(FTRACE_ENABLE_CALLS);
 	mutex_unlock(&ftrace_lock);
 
+	trace_parser_put(parser);
 	kfree(iter);
+
 	mutex_unlock(&ftrace_regex_lock);
 	return 0;
 }
@@ -2457,11 +2414,9 @@ unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly;
 static void *
 __g_next(struct seq_file *m, loff_t *pos)
 {
-	unsigned long *array = m->private;
-
 	if (*pos >= ftrace_graph_count)
 		return NULL;
-	return &array[*pos];
+	return &ftrace_graph_funcs[*pos];
 }
 
 static void *
@@ -2499,12 +2454,12 @@ static int g_show(struct seq_file *m, void *v)
 		return 0;
 	}
 
-	seq_printf(m, "%pf\n", v);
+	seq_printf(m, "%ps\n", (void *)*ptr);
 
 	return 0;
 }
 
-static struct seq_operations ftrace_graph_seq_ops = {
+static const struct seq_operations ftrace_graph_seq_ops = {
 	.start = g_start,
 	.next = g_next,
 	.stop = g_stop,
@@ -2525,16 +2480,10 @@ ftrace_graph_open(struct inode *inode, struct file *file)
 		ftrace_graph_count = 0;
 		memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs));
 	}
+	mutex_unlock(&graph_lock);
 
-	if (file->f_mode & FMODE_READ) {
+	if (file->f_mode & FMODE_READ)
 		ret = seq_open(file, &ftrace_graph_seq_ops);
-		if (!ret) {
-			struct seq_file *m = file->private_data;
-			m->private = ftrace_graph_funcs;
-		}
-	} else
-		file->private_data = ftrace_graph_funcs;
-	mutex_unlock(&graph_lock);
 
 	return ret;
 }
@@ -2602,12 +2551,9 @@ static ssize_t
 ftrace_graph_write(struct file *file, const char __user *ubuf,
 		   size_t cnt, loff_t *ppos)
 {
-	unsigned char buffer[FTRACE_BUFF_MAX+1];
-	unsigned long *array;
+	struct trace_parser parser;
 	size_t read = 0;
 	ssize_t ret;
-	int index = 0;
-	char ch;
 
 	if (!cnt || cnt < 0)
 		return 0;
@@ -2619,57 +2565,26 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
 		goto out;
 	}
 
-	if (file->f_mode & FMODE_READ) {
-		struct seq_file *m = file->private_data;
-		array = m->private;
-	} else
-		array = file->private_data;
-
-	ret = get_user(ch, ubuf++);
-	if (ret)
+	if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) {
+		ret = -ENOMEM;
 		goto out;
-	read++;
-	cnt--;
-
-	/* skip white space */
-	while (cnt && isspace(ch)) {
-		ret = get_user(ch, ubuf++);
-		if (ret)
-			goto out;
-		read++;
-		cnt--;
 	}
 
-	if (isspace(ch)) {
-		*ppos += read;
-		ret = read;
-		goto out;
-	}
+	read = trace_get_user(&parser, ubuf, cnt, ppos);
 
-	while (cnt && !isspace(ch)) {
-		if (index < FTRACE_BUFF_MAX)
-			buffer[index++] = ch;
-		else {
-			ret = -EINVAL;
-			goto out;
-		}
-		ret = get_user(ch, ubuf++);
+	if (trace_parser_loaded((&parser))) {
+		parser.buffer[parser.idx] = 0;
+
+		/* we allow only one expression at a time */
+		ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count,
+					parser.buffer);
 		if (ret)
 			goto out;
-		read++;
-		cnt--;
 	}
-	buffer[index] = 0;
-
-	/* we allow only one expression at a time */
-	ret = ftrace_set_func(array, &ftrace_graph_count, buffer);
-	if (ret)
-		goto out;
-
-	file->f_pos += read;
 
 	ret = read;
  out:
+	trace_parser_put(&parser);
 	mutex_unlock(&graph_lock);
 
 	return ret;
diff --git a/kernel/trace/power-traces.c b/kernel/trace/power-traces.c
new file mode 100644
index 0000000..e06c6e3
--- /dev/null
+++ b/kernel/trace/power-traces.c
@@ -0,0 +1,20 @@
+/*
+ * Power trace points
+ *
+ * Copyright (C) 2009 Arjan van de Ven <arjan@linux.intel.com>
+ */
+
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/power.h>
+
+EXPORT_TRACEPOINT_SYMBOL_GPL(power_start);
+EXPORT_TRACEPOINT_SYMBOL_GPL(power_end);
+EXPORT_TRACEPOINT_SYMBOL_GPL(power_frequency);
+
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 454e74e..d4ff019 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -201,8 +201,6 @@ int tracing_is_on(void)
 }
 EXPORT_SYMBOL_GPL(tracing_is_on);
 
-#include "trace.h"
-
 #define RB_EVNT_HDR_SIZE (offsetof(struct ring_buffer_event, array))
 #define RB_ALIGNMENT		4U
 #define RB_MAX_SMALL_DATA	(RB_ALIGNMENT * RINGBUF_TYPE_DATA_TYPE_LEN_MAX)
@@ -701,8 +699,8 @@ static int rb_head_page_set(struct ring_buffer_per_cpu *cpu_buffer,
 
 	val &= ~RB_FLAG_MASK;
 
-	ret = (unsigned long)cmpxchg(&list->next,
-				     val | old_flag, val | new_flag);
+	ret = cmpxchg((unsigned long *)&list->next,
+		      val | old_flag, val | new_flag);
 
 	/* check if the reader took the page */
 	if ((ret & ~RB_FLAG_MASK) != val)
@@ -794,7 +792,7 @@ static int rb_head_page_replace(struct buffer_page *old,
 	val = *ptr & ~RB_FLAG_MASK;
 	val |= RB_PAGE_HEAD;
 
-	ret = cmpxchg(ptr, val, &new->list);
+	ret = cmpxchg(ptr, val, (unsigned long)&new->list);
 
 	return ret == val;
 }
@@ -2997,15 +2995,12 @@ static void rb_advance_iter(struct ring_buffer_iter *iter)
 }
 
 static struct ring_buffer_event *
-rb_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
+rb_buffer_peek(struct ring_buffer_per_cpu *cpu_buffer, u64 *ts)
 {
-	struct ring_buffer_per_cpu *cpu_buffer;
 	struct ring_buffer_event *event;
 	struct buffer_page *reader;
 	int nr_loops = 0;
 
-	cpu_buffer = buffer->buffers[cpu];
-
  again:
 	/*
 	 * We repeat when a timestamp is encountered. It is possible
@@ -3049,7 +3044,7 @@ rb_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
 	case RINGBUF_TYPE_DATA:
 		if (ts) {
 			*ts = cpu_buffer->read_stamp + event->time_delta;
-			ring_buffer_normalize_time_stamp(buffer,
+			ring_buffer_normalize_time_stamp(cpu_buffer->buffer,
 							 cpu_buffer->cpu, ts);
 		}
 		return event;
@@ -3168,7 +3163,7 @@ ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
 	local_irq_save(flags);
 	if (dolock)
 		spin_lock(&cpu_buffer->reader_lock);
-	event = rb_buffer_peek(buffer, cpu, ts);
+	event = rb_buffer_peek(cpu_buffer, ts);
 	if (event && event->type_len == RINGBUF_TYPE_PADDING)
 		rb_advance_reader(cpu_buffer);
 	if (dolock)
@@ -3237,7 +3232,7 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
 	if (dolock)
 		spin_lock(&cpu_buffer->reader_lock);
 
-	event = rb_buffer_peek(buffer, cpu, ts);
+	event = rb_buffer_peek(cpu_buffer, ts);
 	if (event)
 		rb_advance_reader(cpu_buffer);
 
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 5c75dee..6c0f6a8 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -125,13 +125,13 @@ int ftrace_dump_on_oops;
 
 static int tracing_set_tracer(const char *buf);
 
-#define BOOTUP_TRACER_SIZE		100
-static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata;
+#define MAX_TRACER_SIZE		100
+static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata;
 static char *default_bootup_tracer;
 
 static int __init set_ftrace(char *str)
 {
-	strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE);
+	strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE);
 	default_bootup_tracer = bootup_tracer_buf;
 	/* We are using ftrace early, expand it */
 	ring_buffer_expanded = 1;
@@ -242,13 +242,6 @@ static struct tracer		*trace_types __read_mostly;
 static struct tracer		*current_trace __read_mostly;
 
 /*
- * max_tracer_type_len is used to simplify the allocating of
- * buffers to read userspace tracer names. We keep track of
- * the longest tracer name registered.
- */
-static int			max_tracer_type_len;
-
-/*
  * trace_types_lock is used to protect the trace_types list.
  * This lock is also used to keep user access serialized.
  * Accesses from userspace will grab this lock while userspace
@@ -275,12 +268,18 @@ static DEFINE_SPINLOCK(tracing_start_lock);
  */
 void trace_wake_up(void)
 {
+	int cpu;
+
+	if (trace_flags & TRACE_ITER_BLOCK)
+		return;
 	/*
 	 * The runqueue_is_locked() can fail, but this is the best we
 	 * have for now:
 	 */
-	if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked())
+	cpu = get_cpu();
+	if (!runqueue_is_locked(cpu))
 		wake_up(&trace_wait);
+	put_cpu();
 }
 
 static int __init set_buf_size(char *str)
@@ -339,6 +338,112 @@ static struct {
 
 int trace_clock_id;
 
+/*
+ * trace_parser_get_init - gets the buffer for trace parser
+ */
+int trace_parser_get_init(struct trace_parser *parser, int size)
+{
+	memset(parser, 0, sizeof(*parser));
+
+	parser->buffer = kmalloc(size, GFP_KERNEL);
+	if (!parser->buffer)
+		return 1;
+
+	parser->size = size;
+	return 0;
+}
+
+/*
+ * trace_parser_put - frees the buffer for trace parser
+ */
+void trace_parser_put(struct trace_parser *parser)
+{
+	kfree(parser->buffer);
+}
+
+/*
+ * trace_get_user - reads the user input string separated by  space
+ * (matched by isspace(ch))
+ *
+ * For each string found the 'struct trace_parser' is updated,
+ * and the function returns.
+ *
+ * Returns number of bytes read.
+ *
+ * See kernel/trace/trace.h for 'struct trace_parser' details.
+ */
+int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
+	size_t cnt, loff_t *ppos)
+{
+	char ch;
+	size_t read = 0;
+	ssize_t ret;
+
+	if (!*ppos)
+		trace_parser_clear(parser);
+
+	ret = get_user(ch, ubuf++);
+	if (ret)
+		goto out;
+
+	read++;
+	cnt--;
+
+	/*
+	 * The parser is not finished with the last write,
+	 * continue reading the user input without skipping spaces.
+	 */
+	if (!parser->cont) {
+		/* skip white space */
+		while (cnt && isspace(ch)) {
+			ret = get_user(ch, ubuf++);
+			if (ret)
+				goto out;
+			read++;
+			cnt--;
+		}
+
+		/* only spaces were written */
+		if (isspace(ch)) {
+			*ppos += read;
+			ret = read;
+			goto out;
+		}
+
+		parser->idx = 0;
+	}
+
+	/* read the non-space input */
+	while (cnt && !isspace(ch)) {
+		if (parser->idx < parser->size)
+			parser->buffer[parser->idx++] = ch;
+		else {
+			ret = -EINVAL;
+			goto out;
+		}
+		ret = get_user(ch, ubuf++);
+		if (ret)
+			goto out;
+		read++;
+		cnt--;
+	}
+
+	/* We either got finished input or we have to wait for another call. */
+	if (isspace(ch)) {
+		parser->buffer[parser->idx] = 0;
+		parser->cont = false;
+	} else {
+		parser->cont = true;
+		parser->buffer[parser->idx++] = ch;
+	}
+
+	*ppos += read;
+	ret = read;
+
+out:
+	return ret;
+}
+
 ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
 {
 	int len;
@@ -513,7 +618,6 @@ __releases(kernel_lock)
 __acquires(kernel_lock)
 {
 	struct tracer *t;
-	int len;
 	int ret = 0;
 
 	if (!type->name) {
@@ -521,6 +625,11 @@ __acquires(kernel_lock)
 		return -1;
 	}
 
+	if (strlen(type->name) > MAX_TRACER_SIZE) {
+		pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE);
+		return -1;
+	}
+
 	/*
 	 * When this gets called we hold the BKL which means that
 	 * preemption is disabled. Various trace selftests however
@@ -535,7 +644,7 @@ __acquires(kernel_lock)
 	for (t = trace_types; t; t = t->next) {
 		if (strcmp(type->name, t->name) == 0) {
 			/* already found */
-			pr_info("Trace %s already registered\n",
+			pr_info("Tracer %s already registered\n",
 				type->name);
 			ret = -1;
 			goto out;
@@ -586,9 +695,6 @@ __acquires(kernel_lock)
 
 	type->next = trace_types;
 	trace_types = type;
-	len = strlen(type->name);
-	if (len > max_tracer_type_len)
-		max_tracer_type_len = len;
 
  out:
 	tracing_selftest_running = false;
@@ -597,7 +703,7 @@ __acquires(kernel_lock)
 	if (ret || !default_bootup_tracer)
 		goto out_unlock;
 
-	if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE))
+	if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE))
 		goto out_unlock;
 
 	printk(KERN_INFO "Starting tracer '%s'\n", type->name);
@@ -619,14 +725,13 @@ __acquires(kernel_lock)
 void unregister_tracer(struct tracer *type)
 {
 	struct tracer **t;
-	int len;
 
 	mutex_lock(&trace_types_lock);
 	for (t = &trace_types; *t; t = &(*t)->next) {
 		if (*t == type)
 			goto found;
 	}
-	pr_info("Trace %s not registered\n", type->name);
+	pr_info("Tracer %s not registered\n", type->name);
 	goto out;
 
  found:
@@ -639,17 +744,7 @@ void unregister_tracer(struct tracer *type)
 			current_trace->stop(&global_trace);
 		current_trace = &nop_trace;
 	}
-
-	if (strlen(type->name) != max_tracer_type_len)
-		goto out;
-
-	max_tracer_type_len = 0;
-	for (t = &trace_types; *t; t = &(*t)->next) {
-		len = strlen((*t)->name);
-		if (len > max_tracer_type_len)
-			max_tracer_type_len = len;
-	}
- out:
+out:
 	mutex_unlock(&trace_types_lock);
 }
 
@@ -719,6 +814,11 @@ static void trace_init_cmdlines(void)
 	cmdline_idx = 0;
 }
 
+int is_tracing_stopped(void)
+{
+	return trace_stop_count;
+}
+
 /**
  * ftrace_off_permanent - disable all ftrace code permanently
  *
@@ -886,7 +986,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
 
 	entry->preempt_count		= pc & 0xff;
 	entry->pid			= (tsk) ? tsk->pid : 0;
-	entry->tgid			= (tsk) ? tsk->tgid : 0;
+	entry->lock_depth		= (tsk) ? tsk->lock_depth : 0;
 	entry->flags =
 #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
 		(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
@@ -1068,6 +1168,7 @@ ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc)
 		return;
 	entry	= ring_buffer_event_data(event);
 
+	entry->tgid		= current->tgid;
 	memset(&entry->caller, 0, sizeof(entry->caller));
 
 	trace.nr_entries	= 0;
@@ -1094,6 +1195,7 @@ ftrace_trace_special(void *__tr,
 		     unsigned long arg1, unsigned long arg2, unsigned long arg3,
 		     int pc)
 {
+	struct ftrace_event_call *call = &event_special;
 	struct ring_buffer_event *event;
 	struct trace_array *tr = __tr;
 	struct ring_buffer *buffer = tr->buffer;
@@ -1107,7 +1209,9 @@ ftrace_trace_special(void *__tr,
 	entry->arg1			= arg1;
 	entry->arg2			= arg2;
 	entry->arg3			= arg3;
-	trace_buffer_unlock_commit(buffer, event, 0, pc);
+
+	if (!filter_check_discard(call, entry, buffer, event))
+		trace_buffer_unlock_commit(buffer, event, 0, pc);
 }
 
 void
@@ -1530,10 +1634,10 @@ static void print_lat_help_header(struct seq_file *m)
 	seq_puts(m, "#                | / _----=> need-resched    \n");
 	seq_puts(m, "#                || / _---=> hardirq/softirq \n");
 	seq_puts(m, "#                ||| / _--=> preempt-depth   \n");
-	seq_puts(m, "#                |||| /                      \n");
-	seq_puts(m, "#                |||||     delay             \n");
-	seq_puts(m, "#  cmd     pid   ||||| time  |   caller      \n");
-	seq_puts(m, "#     \\   /      |||||   \\   |   /           \n");
+	seq_puts(m, "#                |||| /_--=> lock-depth       \n");
+	seq_puts(m, "#                |||||/     delay             \n");
+	seq_puts(m, "#  cmd     pid   |||||| time  |   caller      \n");
+	seq_puts(m, "#     \\   /      ||||||   \\   |   /           \n");
 }
 
 static void print_func_help_header(struct seq_file *m)
@@ -1845,7 +1949,7 @@ static int s_show(struct seq_file *m, void *v)
 	return 0;
 }
 
-static struct seq_operations tracer_seq_ops = {
+static const struct seq_operations tracer_seq_ops = {
 	.start		= s_start,
 	.next		= s_next,
 	.stop		= s_stop,
@@ -2059,7 +2163,7 @@ static int t_show(struct seq_file *m, void *v)
 	return 0;
 }
 
-static struct seq_operations show_traces_seq_ops = {
+static const struct seq_operations show_traces_seq_ops = {
 	.start		= t_start,
 	.next		= t_next,
 	.stop		= t_stop,
@@ -2489,7 +2593,7 @@ static ssize_t
 tracing_set_trace_read(struct file *filp, char __user *ubuf,
 		       size_t cnt, loff_t *ppos)
 {
-	char buf[max_tracer_type_len+2];
+	char buf[MAX_TRACER_SIZE+2];
 	int r;
 
 	mutex_lock(&trace_types_lock);
@@ -2639,15 +2743,15 @@ static ssize_t
 tracing_set_trace_write(struct file *filp, const char __user *ubuf,
 			size_t cnt, loff_t *ppos)
 {
-	char buf[max_tracer_type_len+1];
+	char buf[MAX_TRACER_SIZE+1];
 	int i;
 	size_t ret;
 	int err;
 
 	ret = cnt;
 
-	if (cnt > max_tracer_type_len)
-		cnt = max_tracer_type_len;
+	if (cnt > MAX_TRACER_SIZE)
+		cnt = MAX_TRACER_SIZE;
 
 	if (copy_from_user(&buf, ubuf, cnt))
 		return -EFAULT;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 8210649..104c1a7 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -7,10 +7,10 @@
 #include <linux/clocksource.h>
 #include <linux/ring_buffer.h>
 #include <linux/mmiotrace.h>
+#include <linux/tracepoint.h>
 #include <linux/ftrace.h>
 #include <trace/boot.h>
 #include <linux/kmemtrace.h>
-#include <trace/power.h>
 
 #include <linux/trace_seq.h>
 #include <linux/ftrace_event.h>
@@ -36,163 +36,59 @@ enum trace_type {
 	TRACE_HW_BRANCHES,
 	TRACE_KMEM_ALLOC,
 	TRACE_KMEM_FREE,
-	TRACE_POWER,
 	TRACE_BLK,
 
 	__TRACE_LAST_TYPE,
 };
 
-/*
- * Function trace entry - function address and parent function addres:
- */
-struct ftrace_entry {
-	struct trace_entry	ent;
-	unsigned long		ip;
-	unsigned long		parent_ip;
-};
-
-/* Function call entry */
-struct ftrace_graph_ent_entry {
-	struct trace_entry		ent;
-	struct ftrace_graph_ent		graph_ent;
+enum kmemtrace_type_id {
+	KMEMTRACE_TYPE_KMALLOC = 0,	/* kmalloc() or kfree(). */
+	KMEMTRACE_TYPE_CACHE,		/* kmem_cache_*(). */
+	KMEMTRACE_TYPE_PAGES,		/* __get_free_pages() and friends. */
 };
 
-/* Function return entry */
-struct ftrace_graph_ret_entry {
-	struct trace_entry		ent;
-	struct ftrace_graph_ret		ret;
-};
 extern struct tracer boot_tracer;
 
-/*
- * Context switch trace entry - which task (and prio) we switched from/to:
- */
-struct ctx_switch_entry {
-	struct trace_entry	ent;
-	unsigned int		prev_pid;
-	unsigned char		prev_prio;
-	unsigned char		prev_state;
-	unsigned int		next_pid;
-	unsigned char		next_prio;
-	unsigned char		next_state;
-	unsigned int		next_cpu;
-};
-
-/*
- * Special (free-form) trace entry:
- */
-struct special_entry {
-	struct trace_entry	ent;
-	unsigned long		arg1;
-	unsigned long		arg2;
-	unsigned long		arg3;
-};
-
-/*
- * Stack-trace entry:
- */
-
-#define FTRACE_STACK_ENTRIES	8
+#undef __field
+#define __field(type, item)		type	item;
 
-struct stack_entry {
-	struct trace_entry	ent;
-	unsigned long		caller[FTRACE_STACK_ENTRIES];
-};
+#undef __field_struct
+#define __field_struct(type, item)	__field(type, item)
 
-struct userstack_entry {
-	struct trace_entry	ent;
-	unsigned long		caller[FTRACE_STACK_ENTRIES];
-};
+#undef __field_desc
+#define __field_desc(type, container, item)
 
-/*
- * trace_printk entry:
- */
-struct bprint_entry {
-	struct trace_entry	ent;
-	unsigned long		ip;
-	const char		*fmt;
-	u32			buf[];
-};
+#undef __array
+#define __array(type, item, size)	type	item[size];
 
-struct print_entry {
-	struct trace_entry	ent;
-	unsigned long		ip;
-	char			buf[];
-};
-
-#define TRACE_OLD_SIZE		88
-
-struct trace_field_cont {
-	unsigned char		type;
-	/* Temporary till we get rid of this completely */
-	char			buf[TRACE_OLD_SIZE - 1];
-};
+#undef __array_desc
+#define __array_desc(type, container, item, size)
 
-struct trace_mmiotrace_rw {
-	struct trace_entry	ent;
-	struct mmiotrace_rw	rw;
-};
+#undef __dynamic_array
+#define __dynamic_array(type, item)	type	item[];
 
-struct trace_mmiotrace_map {
-	struct trace_entry	ent;
-	struct mmiotrace_map	map;
-};
-
-struct trace_boot_call {
-	struct trace_entry	ent;
-	struct boot_trace_call boot_call;
-};
+#undef F_STRUCT
+#define F_STRUCT(args...)		args
 
-struct trace_boot_ret {
-	struct trace_entry	ent;
-	struct boot_trace_ret boot_ret;
-};
+#undef FTRACE_ENTRY
+#define FTRACE_ENTRY(name, struct_name, id, tstruct, print)	\
+	struct struct_name {					\
+		struct trace_entry	ent;			\
+		tstruct						\
+	}
 
-#define TRACE_FUNC_SIZE 30
-#define TRACE_FILE_SIZE 20
-struct trace_branch {
-	struct trace_entry	ent;
-	unsigned	        line;
-	char			func[TRACE_FUNC_SIZE+1];
-	char			file[TRACE_FILE_SIZE+1];
-	char			correct;
-};
+#undef TP_ARGS
+#define TP_ARGS(args...)	args
 
-struct hw_branch_entry {
-	struct trace_entry	ent;
-	u64			from;
-	u64			to;
-};
+#undef FTRACE_ENTRY_DUP
+#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
 
-struct trace_power {
-	struct trace_entry	ent;
-	struct power_trace	state_data;
-};
-
-enum kmemtrace_type_id {
-	KMEMTRACE_TYPE_KMALLOC = 0,	/* kmalloc() or kfree(). */
-	KMEMTRACE_TYPE_CACHE,		/* kmem_cache_*(). */
-	KMEMTRACE_TYPE_PAGES,		/* __get_free_pages() and friends. */
-};
-
-struct kmemtrace_alloc_entry {
-	struct trace_entry	ent;
-	enum kmemtrace_type_id type_id;
-	unsigned long call_site;
-	const void *ptr;
-	size_t bytes_req;
-	size_t bytes_alloc;
-	gfp_t gfp_flags;
-	int node;
-};
-
-struct kmemtrace_free_entry {
-	struct trace_entry	ent;
-	enum kmemtrace_type_id type_id;
-	unsigned long call_site;
-	const void *ptr;
-};
+#include "trace_entries.h"
 
+/*
+ * syscalls are special, and need special handling, this is why
+ * they are not included in trace_entries.h
+ */
 struct syscall_trace_enter {
 	struct trace_entry	ent;
 	int			nr;
@@ -228,14 +124,12 @@ struct kretprobe_trace_entry {
 	(offsetof(struct kretprobe_trace_entry, args) +	\
 	(sizeof(unsigned long) * (n)))
 
-
-
 /*
  * trace_flag_type is an enumeration that holds different
  * states when a trace occurs. These are:
  *  IRQS_OFF		- interrupts were disabled
  *  IRQS_NOSUPPORT	- arch does not support irqs_disabled_flags
- *  NEED_RESCED		- reschedule is requested
+ *  NEED_RESCHED	- reschedule is requested
  *  HARDIRQ		- inside an interrupt handler
  *  SOFTIRQ		- inside a softirq handler
  */
@@ -334,7 +228,6 @@ extern void __ftrace_bad_type(void);
 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
 			  TRACE_GRAPH_RET);		\
 		IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
-		IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
 		IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry,	\
 			  TRACE_KMEM_ALLOC);	\
 		IF_ASSIGN(var, ent, struct kmemtrace_free_entry,	\
@@ -414,7 +307,6 @@ struct tracer {
 	struct tracer		*next;
 	int			print_max;
 	struct tracer_flags	*flags;
-	struct tracer_stat	*stats;
 };
 
 
@@ -493,6 +385,7 @@ void tracing_stop_sched_switch_record(void);
 void tracing_start_sched_switch_record(void);
 int register_tracer(struct tracer *type);
 void unregister_tracer(struct tracer *type);
+int is_tracing_stopped(void);
 
 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 
@@ -533,20 +426,6 @@ static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
 
 extern cycle_t ftrace_now(int cpu);
 
-#ifdef CONFIG_CONTEXT_SWITCH_TRACER
-typedef void
-(*tracer_switch_func_t)(void *private,
-			void *__rq,
-			struct task_struct *prev,
-			struct task_struct *next);
-
-struct tracer_switch_ops {
-	tracer_switch_func_t		func;
-	void				*private;
-	struct tracer_switch_ops	*next;
-};
-#endif /* CONFIG_CONTEXT_SWITCH_TRACER */
-
 extern void trace_find_cmdline(int pid, char comm[]);
 
 #ifdef CONFIG_DYNAMIC_FTRACE
@@ -662,6 +541,41 @@ static inline int ftrace_trace_task(struct task_struct *task)
 #endif
 
 /*
+ * struct trace_parser - servers for reading the user input separated by spaces
+ * @cont: set if the input is not complete - no final space char was found
+ * @buffer: holds the parsed user input
+ * @idx: user input lenght
+ * @size: buffer size
+ */
+struct trace_parser {
+	bool		cont;
+	char		*buffer;
+	unsigned	idx;
+	unsigned	size;
+};
+
+static inline bool trace_parser_loaded(struct trace_parser *parser)
+{
+	return (parser->idx != 0);
+}
+
+static inline bool trace_parser_cont(struct trace_parser *parser)
+{
+	return parser->cont;
+}
+
+static inline void trace_parser_clear(struct trace_parser *parser)
+{
+	parser->cont = false;
+	parser->idx = 0;
+}
+
+extern int trace_parser_get_init(struct trace_parser *parser, int size);
+extern void trace_parser_put(struct trace_parser *parser);
+extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
+	size_t cnt, loff_t *ppos);
+
+/*
  * trace_iterator_flags is an enumeration that defines bit
  * positions into trace_flags that controls the output.
  *
@@ -847,58 +761,18 @@ filter_check_discard(struct ftrace_event_call *call, void *rec,
 	return 0;
 }
 
-#define DEFINE_COMPARISON_PRED(type)					\
-static int filter_pred_##type(struct filter_pred *pred, void *event,	\
-			      int val1, int val2)			\
-{									\
-	type *addr = (type *)(event + pred->offset);			\
-	type val = (type)pred->val;					\
-	int match = 0;							\
-									\
-	switch (pred->op) {						\
-	case OP_LT:							\
-		match = (*addr < val);					\
-		break;							\
-	case OP_LE:							\
-		match = (*addr <= val);					\
-		break;							\
-	case OP_GT:							\
-		match = (*addr > val);					\
-		break;							\
-	case OP_GE:							\
-		match = (*addr >= val);					\
-		break;							\
-	default:							\
-		break;							\
-	}								\
-									\
-	return match;							\
-}
-
-#define DEFINE_EQUALITY_PRED(size)					\
-static int filter_pred_##size(struct filter_pred *pred, void *event,	\
-			      int val1, int val2)			\
-{									\
-	u##size *addr = (u##size *)(event + pred->offset);		\
-	u##size val = (u##size)pred->val;				\
-	int match;							\
-									\
-	match = (val == *addr) ^ pred->not;				\
-									\
-	return match;							\
-}
-
 extern struct mutex event_mutex;
 extern struct list_head ftrace_events;
 
 extern const char *__start___trace_bprintk_fmt[];
 extern const char *__stop___trace_bprintk_fmt[];
 
-#undef TRACE_EVENT_FORMAT
-#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)	\
+#undef FTRACE_ENTRY
+#define FTRACE_ENTRY(call, struct_name, id, tstruct, print)		\
 	extern struct ftrace_event_call event_##call;
-#undef TRACE_EVENT_FORMAT_NOFILTER
-#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, tpfmt)
-#include "trace_event_types.h"
+#undef FTRACE_ENTRY_DUP
+#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)		\
+	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
+#include "trace_entries.h"
 
 #endif /* _LINUX_KERNEL_TRACE_H */
diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
index 19bfc75..c21d5f3 100644
--- a/kernel/trace/trace_boot.c
+++ b/kernel/trace/trace_boot.c
@@ -129,6 +129,7 @@ struct tracer boot_tracer __read_mostly =
 
 void trace_boot_call(struct boot_trace_call *bt, initcall_t fn)
 {
+	struct ftrace_event_call *call = &event_boot_call;
 	struct ring_buffer_event *event;
 	struct ring_buffer *buffer;
 	struct trace_boot_call *entry;
@@ -150,13 +151,15 @@ void trace_boot_call(struct boot_trace_call *bt, initcall_t fn)
 		goto out;
 	entry	= ring_buffer_event_data(event);
 	entry->boot_call = *bt;
-	trace_buffer_unlock_commit(buffer, event, 0, 0);
+	if (!filter_check_discard(call, entry, buffer, event))
+		trace_buffer_unlock_commit(buffer, event, 0, 0);
  out:
 	preempt_enable();
 }
 
 void trace_boot_ret(struct boot_trace_ret *bt, initcall_t fn)
 {
+	struct ftrace_event_call *call = &event_boot_ret;
 	struct ring_buffer_event *event;
 	struct ring_buffer *buffer;
 	struct trace_boot_ret *entry;
@@ -175,7 +178,8 @@ void trace_boot_ret(struct boot_trace_ret *bt, initcall_t fn)
 		goto out;
 	entry	= ring_buffer_event_data(event);
 	entry->boot_ret = *bt;
-	trace_buffer_unlock_commit(buffer, event, 0, 0);
+	if (!filter_check_discard(call, entry, buffer, event))
+		trace_buffer_unlock_commit(buffer, event, 0, 0);
  out:
 	preempt_enable();
 }
diff --git a/kernel/trace/trace_clock.c b/kernel/trace/trace_clock.c
index b588fd8..20c5f92 100644
--- a/kernel/trace/trace_clock.c
+++ b/kernel/trace/trace_clock.c
@@ -66,10 +66,14 @@ u64 notrace trace_clock(void)
  * Used by plugins that need globally coherent timestamps.
  */
 
-static u64 prev_trace_clock_time;
-
-static raw_spinlock_t trace_clock_lock ____cacheline_aligned_in_smp =
-	(raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
+/* keep prev_time and lock in the same cacheline. */
+static struct {
+	u64 prev_time;
+	raw_spinlock_t lock;
+} trace_clock_struct ____cacheline_aligned_in_smp =
+	{
+		.lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED,
+	};
 
 u64 notrace trace_clock_global(void)
 {
@@ -88,19 +92,19 @@ u64 notrace trace_clock_global(void)
 	if (unlikely(in_nmi()))
 		goto out;
 
-	__raw_spin_lock(&trace_clock_lock);
+	__raw_spin_lock(&trace_clock_struct.lock);
 
 	/*
 	 * TODO: if this happens often then maybe we should reset
-	 * my_scd->clock to prev_trace_clock_time+1, to make sure
+	 * my_scd->clock to prev_time+1, to make sure
 	 * we start ticking with the local clock from now on?
 	 */
-	if ((s64)(now - prev_trace_clock_time) < 0)
-		now = prev_trace_clock_time + 1;
+	if ((s64)(now - trace_clock_struct.prev_time) < 0)
+		now = trace_clock_struct.prev_time + 1;
 
-	prev_trace_clock_time = now;
+	trace_clock_struct.prev_time = now;
 
-	__raw_spin_unlock(&trace_clock_lock);
+	__raw_spin_unlock(&trace_clock_struct.lock);
 
  out:
 	raw_local_irq_restore(flags);
diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
new file mode 100644
index 0000000..ead3d72
--- /dev/null
+++ b/kernel/trace/trace_entries.h
@@ -0,0 +1,366 @@
+/*
+ * This file defines the trace event structures that go into the ring
+ * buffer directly. They are created via macros so that changes for them
+ * appear in the format file. Using macros will automate this process.
+ *
+ * The macro used to create a ftrace data structure is:
+ *
+ * FTRACE_ENTRY( name, struct_name, id, structure, print )
+ *
+ * @name: the name used the event name, as well as the name of
+ *   the directory that holds the format file.
+ *
+ * @struct_name: the name of the structure that is created.
+ *
+ * @id: The event identifier that is used to detect what event
+ *    this is from the ring buffer.
+ *
+ * @structure: the structure layout
+ *
+ *  - __field(	type,	item	)
+ *	  This is equivalent to declaring
+ *		type	item;
+ *	  in the structure.
+ *  - __array(	type,	item,	size	)
+ *	  This is equivalent to declaring
+ *		type	item[size];
+ *	  in the structure.
+ *
+ *   * for structures within structures, the format of the internal
+ *	structure is layed out. This allows the internal structure
+ *	to be deciphered for the format file. Although these macros
+ *	may become out of sync with the internal structure, they
+ *	will create a compile error if it happens. Since the
+ *	internel structures are just tracing helpers, this is not
+ *	an issue.
+ *
+ *	When an internal structure is used, it should use:
+ *
+ *	__field_struct(	type,	item	)
+ *
+ *	instead of __field. This will prevent it from being shown in
+ *	the output file. The fields in the structure should use.
+ *
+ *	__field_desc(	type,	container,	item		)
+ *	__array_desc(	type,	container,	item,	len	)
+ *
+ *	type, item and len are the same as __field and __array, but
+ *	container is added. This is the name of the item in
+ *	__field_struct that this is describing.
+ *
+ *
+ * @print: the print format shown to users in the format file.
+ */
+
+/*
+ * Function trace entry - function address and parent function addres:
+ */
+FTRACE_ENTRY(function, ftrace_entry,
+
+	TRACE_FN,
+
+	F_STRUCT(
+		__field(	unsigned long,	ip		)
+		__field(	unsigned long,	parent_ip	)
+	),
+
+	F_printk(" %lx <-- %lx", __entry->ip, __entry->parent_ip)
+);
+
+/* Function call entry */
+FTRACE_ENTRY(funcgraph_entry, ftrace_graph_ent_entry,
+
+	TRACE_GRAPH_ENT,
+
+	F_STRUCT(
+		__field_struct(	struct ftrace_graph_ent,	graph_ent	)
+		__field_desc(	unsigned long,	graph_ent,	func		)
+		__field_desc(	int,		graph_ent,	depth		)
+	),
+
+	F_printk("--> %lx (%d)", __entry->func, __entry->depth)
+);
+
+/* Function return entry */
+FTRACE_ENTRY(funcgraph_exit, ftrace_graph_ret_entry,
+
+	TRACE_GRAPH_RET,
+
+	F_STRUCT(
+		__field_struct(	struct ftrace_graph_ret,	ret	)
+		__field_desc(	unsigned long,	ret,		func	)
+		__field_desc(	unsigned long long, ret,	calltime)
+		__field_desc(	unsigned long long, ret,	rettime	)
+		__field_desc(	unsigned long,	ret,		overrun	)
+		__field_desc(	int,		ret,		depth	)
+	),
+
+	F_printk("<-- %lx (%d) (start: %llx  end: %llx) over: %d",
+		 __entry->func, __entry->depth,
+		 __entry->calltime, __entry->rettime,
+		 __entry->depth)
+);
+
+/*
+ * Context switch trace entry - which task (and prio) we switched from/to:
+ *
+ * This is used for both wakeup and context switches. We only want
+ * to create one structure, but we need two outputs for it.
+ */
+#define FTRACE_CTX_FIELDS					\
+	__field(	unsigned int,	prev_pid	)	\
+	__field(	unsigned char,	prev_prio	)	\
+	__field(	unsigned char,	prev_state	)	\
+	__field(	unsigned int,	next_pid	)	\
+	__field(	unsigned char,	next_prio	)	\
+	__field(	unsigned char,	next_state	)	\
+	__field(	unsigned int,	next_cpu	)
+
+FTRACE_ENTRY(context_switch, ctx_switch_entry,
+
+	TRACE_CTX,
+
+	F_STRUCT(
+		FTRACE_CTX_FIELDS
+	),
+
+	F_printk("%u:%u:%u  ==> %u:%u:%u [%03u]",
+		 __entry->prev_pid, __entry->prev_prio, __entry->prev_state,
+		 __entry->next_pid, __entry->next_prio, __entry->next_state,
+		 __entry->next_cpu
+		)
+);
+
+/*
+ * FTRACE_ENTRY_DUP only creates the format file, it will not
+ *  create another structure.
+ */
+FTRACE_ENTRY_DUP(wakeup, ctx_switch_entry,
+
+	TRACE_WAKE,
+
+	F_STRUCT(
+		FTRACE_CTX_FIELDS
+	),
+
+	F_printk("%u:%u:%u  ==+ %u:%u:%u [%03u]",
+		 __entry->prev_pid, __entry->prev_prio, __entry->prev_state,
+		 __entry->next_pid, __entry->next_prio, __entry->next_state,
+		 __entry->next_cpu
+		)
+);
+
+/*
+ * Special (free-form) trace entry:
+ */
+FTRACE_ENTRY(special, special_entry,
+
+	TRACE_SPECIAL,
+
+	F_STRUCT(
+		__field(	unsigned long,	arg1	)
+		__field(	unsigned long,	arg2	)
+		__field(	unsigned long,	arg3	)
+	),
+
+	F_printk("(%08lx) (%08lx) (%08lx)",
+		 __entry->arg1, __entry->arg2, __entry->arg3)
+);
+
+/*
+ * Stack-trace entry:
+ */
+
+#define FTRACE_STACK_ENTRIES	8
+
+FTRACE_ENTRY(kernel_stack, stack_entry,
+
+	TRACE_STACK,
+
+	F_STRUCT(
+		__array(	unsigned long,	caller, FTRACE_STACK_ENTRIES	)
+	),
+
+	F_printk("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n"
+		 "\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n",
+		 __entry->caller[0], __entry->caller[1], __entry->caller[2],
+		 __entry->caller[3], __entry->caller[4], __entry->caller[5],
+		 __entry->caller[6], __entry->caller[7])
+);
+
+FTRACE_ENTRY(user_stack, userstack_entry,
+
+	TRACE_USER_STACK,
+
+	F_STRUCT(
+		__field(	unsigned int,	tgid	)
+		__array(	unsigned long,	caller, FTRACE_STACK_ENTRIES	)
+	),
+
+	F_printk("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n"
+		 "\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n",
+		 __entry->caller[0], __entry->caller[1], __entry->caller[2],
+		 __entry->caller[3], __entry->caller[4], __entry->caller[5],
+		 __entry->caller[6], __entry->caller[7])
+);
+
+/*
+ * trace_printk entry:
+ */
+FTRACE_ENTRY(bprint, bprint_entry,
+
+	TRACE_BPRINT,
+
+	F_STRUCT(
+		__field(	unsigned long,	ip	)
+		__field(	const char *,	fmt	)
+		__dynamic_array(	u32,	buf	)
+	),
+
+	F_printk("%08lx fmt:%p",
+		 __entry->ip, __entry->fmt)
+);
+
+FTRACE_ENTRY(print, print_entry,
+
+	TRACE_PRINT,
+
+	F_STRUCT(
+		__field(	unsigned long,	ip	)
+		__dynamic_array(	char,	buf	)
+	),
+
+	F_printk("%08lx %s",
+		 __entry->ip, __entry->buf)
+);
+
+FTRACE_ENTRY(mmiotrace_rw, trace_mmiotrace_rw,
+
+	TRACE_MMIO_RW,
+
+	F_STRUCT(
+		__field_struct(	struct mmiotrace_rw,	rw	)
+		__field_desc(	resource_size_t, rw,	phys	)
+		__field_desc(	unsigned long,	rw,	value	)
+		__field_desc(	unsigned long,	rw,	pc	)
+		__field_desc(	int, 		rw,	map_id	)
+		__field_desc(	unsigned char,	rw,	opcode	)
+		__field_desc(	unsigned char,	rw,	width	)
+	),
+
+	F_printk("%lx %lx %lx %d %x %x",
+		 (unsigned long)__entry->phys, __entry->value, __entry->pc,
+		 __entry->map_id, __entry->opcode, __entry->width)
+);
+
+FTRACE_ENTRY(mmiotrace_map, trace_mmiotrace_map,
+
+	TRACE_MMIO_MAP,
+
+	F_STRUCT(
+		__field_struct(	struct mmiotrace_map,	map	)
+		__field_desc(	resource_size_t, map,	phys	)
+		__field_desc(	unsigned long,	map,	virt	)
+		__field_desc(	unsigned long,	map,	len	)
+		__field_desc(	int, 		map,	map_id	)
+		__field_desc(	unsigned char,	map,	opcode	)
+	),
+
+	F_printk("%lx %lx %lx %d %x",
+		 (unsigned long)__entry->phys, __entry->virt, __entry->len,
+		 __entry->map_id, __entry->opcode)
+);
+
+FTRACE_ENTRY(boot_call, trace_boot_call,
+
+	TRACE_BOOT_CALL,
+
+	F_STRUCT(
+		__field_struct(	struct boot_trace_call,	boot_call	)
+		__field_desc(	pid_t,	boot_call,	caller		)
+		__array_desc(	char,	boot_call,	func,	KSYM_SYMBOL_LEN)
+	),
+
+	F_printk("%d  %s", __entry->caller, __entry->func)
+);
+
+FTRACE_ENTRY(boot_ret, trace_boot_ret,
+
+	TRACE_BOOT_RET,
+
+	F_STRUCT(
+		__field_struct(	struct boot_trace_ret,	boot_ret	)
+		__array_desc(	char,	boot_ret,	func,	KSYM_SYMBOL_LEN)
+		__field_desc(	int,	boot_ret,	result		)
+		__field_desc(	unsigned long, boot_ret, duration	)
+	),
+
+	F_printk("%s %d %lx",
+		 __entry->func, __entry->result, __entry->duration)
+);
+
+#define TRACE_FUNC_SIZE 30
+#define TRACE_FILE_SIZE 20
+
+FTRACE_ENTRY(branch, trace_branch,
+
+	TRACE_BRANCH,
+
+	F_STRUCT(
+		__field(	unsigned int,	line				)
+		__array(	char,		func,	TRACE_FUNC_SIZE+1	)
+		__array(	char,		file,	TRACE_FILE_SIZE+1	)
+		__field(	char,		correct				)
+	),
+
+	F_printk("%u:%s:%s (%u)",
+		 __entry->line,
+		 __entry->func, __entry->file, __entry->correct)
+);
+
+FTRACE_ENTRY(hw_branch, hw_branch_entry,
+
+	TRACE_HW_BRANCHES,
+
+	F_STRUCT(
+		__field(	u64,	from	)
+		__field(	u64,	to	)
+	),
+
+	F_printk("from: %llx to: %llx", __entry->from, __entry->to)
+);
+
+FTRACE_ENTRY(kmem_alloc, kmemtrace_alloc_entry,
+
+	TRACE_KMEM_ALLOC,
+
+	F_STRUCT(
+		__field(	enum kmemtrace_type_id,	type_id		)
+		__field(	unsigned long,		call_site	)
+		__field(	const void *,		ptr		)
+		__field(	size_t,			bytes_req	)
+		__field(	size_t,			bytes_alloc	)
+		__field(	gfp_t,			gfp_flags	)
+		__field(	int,			node		)
+	),
+
+	F_printk("type:%u call_site:%lx ptr:%p req:%zi alloc:%zi"
+		 " flags:%x node:%d",
+		 __entry->type_id, __entry->call_site, __entry->ptr,
+		 __entry->bytes_req, __entry->bytes_alloc,
+		 __entry->gfp_flags, __entry->node)
+);
+
+FTRACE_ENTRY(kmem_free, kmemtrace_free_entry,
+
+	TRACE_KMEM_FREE,
+
+	F_STRUCT(
+		__field(	enum kmemtrace_type_id,	type_id		)
+		__field(	unsigned long,		call_site	)
+		__field(	const void *,		ptr		)
+	),
+
+	F_printk("type:%u call_site:%lx ptr:%p",
+		 __entry->type_id, __entry->call_site, __entry->ptr)
+);
diff --git a/kernel/trace/trace_event_profile.c b/kernel/trace/trace_event_profile.c
index 11ba5bb..e812f1c 100644
--- a/kernel/trace/trace_event_profile.c
+++ b/kernel/trace/trace_event_profile.c
@@ -5,8 +5,60 @@
  *
  */
 
+#include <linux/module.h>
 #include "trace.h"
 
+/*
+ * We can't use a size but a type in alloc_percpu()
+ * So let's create a dummy type that matches the desired size
+ */
+typedef struct {char buf[FTRACE_MAX_PROFILE_SIZE];} profile_buf_t;
+
+char		*trace_profile_buf;
+EXPORT_SYMBOL_GPL(trace_profile_buf);
+
+char		*trace_profile_buf_nmi;
+EXPORT_SYMBOL_GPL(trace_profile_buf_nmi);
+
+/* Count the events in use (per event id, not per instance) */
+static int	total_profile_count;
+
+static int ftrace_profile_enable_event(struct ftrace_event_call *event)
+{
+	char *buf;
+	int ret = -ENOMEM;
+
+	if (atomic_inc_return(&event->profile_count))
+		return 0;
+
+	if (!total_profile_count++) {
+		buf = (char *)alloc_percpu(profile_buf_t);
+		if (!buf)
+			goto fail_buf;
+
+		rcu_assign_pointer(trace_profile_buf, buf);
+
+		buf = (char *)alloc_percpu(profile_buf_t);
+		if (!buf)
+			goto fail_buf_nmi;
+
+		rcu_assign_pointer(trace_profile_buf_nmi, buf);
+	}
+
+	ret = event->profile_enable(event);
+	if (!ret)
+		return 0;
+
+	kfree(trace_profile_buf_nmi);
+fail_buf_nmi:
+	kfree(trace_profile_buf);
+fail_buf:
+	total_profile_count--;
+	atomic_dec(&event->profile_count);
+
+	return ret;
+}
+
 int ftrace_profile_enable(int event_id)
 {
 	struct ftrace_event_call *event;
@@ -14,8 +66,9 @@ int ftrace_profile_enable(int event_id)
 
 	mutex_lock(&event_mutex);
 	list_for_each_entry(event, &ftrace_events, list) {
-		if (event->id == event_id && event->profile_enable) {
-			ret = event->profile_enable(event);
+		if (event->id == event_id && event->profile_enable &&
+		    try_module_get(event->mod)) {
+			ret = ftrace_profile_enable_event(event);
 			break;
 		}
 	}
@@ -24,6 +77,33 @@ int ftrace_profile_enable(int event_id)
 	return ret;
 }
 
+static void ftrace_profile_disable_event(struct ftrace_event_call *event)
+{
+	char *buf, *nmi_buf;
+
+	if (!atomic_add_negative(-1, &event->profile_count))
+		return;
+
+	event->profile_disable(event);
+
+	if (!--total_profile_count) {
+		buf = trace_profile_buf;
+		rcu_assign_pointer(trace_profile_buf, NULL);
+
+		nmi_buf = trace_profile_buf_nmi;
+		rcu_assign_pointer(trace_profile_buf_nmi, NULL);
+
+		/*
+		 * Ensure every events in profiling have finished before
+		 * releasing the buffers
+		 */
+		synchronize_sched();
+
+		free_percpu(buf);
+		free_percpu(nmi_buf);
+	}
+}
+
 void ftrace_profile_disable(int event_id)
 {
 	struct ftrace_event_call *event;
@@ -31,7 +111,8 @@ void ftrace_profile_disable(int event_id)
 	mutex_lock(&event_mutex);
 	list_for_each_entry(event, &ftrace_events, list) {
 		if (event->id == event_id) {
-			event->profile_disable(event);
+			ftrace_profile_disable_event(event);
+			module_put(event->mod);
 			break;
 		}
 	}
diff --git a/kernel/trace/trace_event_types.h b/kernel/trace/trace_event_types.h
deleted file mode 100644
index e74f090..0000000
--- a/kernel/trace/trace_event_types.h
+++ /dev/null
@@ -1,178 +0,0 @@
-#undef TRACE_SYSTEM
-#define TRACE_SYSTEM	ftrace
-
-/*
- * We cheat and use the proto type field as the ID
- * and args as the entry type (minus 'struct')
- */
-TRACE_EVENT_FORMAT(function, TRACE_FN, ftrace_entry, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(unsigned long, ip, ip)
-		TRACE_FIELD(unsigned long, parent_ip, parent_ip)
-	),
-	TP_RAW_FMT(" %lx <-- %lx")
-);
-
-TRACE_EVENT_FORMAT(funcgraph_entry, TRACE_GRAPH_ENT,
-		   ftrace_graph_ent_entry, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(unsigned long, graph_ent.func, func)
-		TRACE_FIELD(int, graph_ent.depth, depth)
-	),
-	TP_RAW_FMT("--> %lx (%d)")
-);
-
-TRACE_EVENT_FORMAT(funcgraph_exit, TRACE_GRAPH_RET,
-		   ftrace_graph_ret_entry, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(unsigned long, ret.func, func)
-		TRACE_FIELD(unsigned long long, ret.calltime, calltime)
-		TRACE_FIELD(unsigned long long, ret.rettime, rettime)
-		TRACE_FIELD(unsigned long, ret.overrun, overrun)
-		TRACE_FIELD(int, ret.depth, depth)
-	),
-	TP_RAW_FMT("<-- %lx (%d)")
-);
-
-TRACE_EVENT_FORMAT(wakeup, TRACE_WAKE, ctx_switch_entry, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(unsigned int, prev_pid, prev_pid)
-		TRACE_FIELD(unsigned char, prev_prio, prev_prio)
-		TRACE_FIELD(unsigned char, prev_state, prev_state)
-		TRACE_FIELD(unsigned int, next_pid, next_pid)
-		TRACE_FIELD(unsigned char, next_prio, next_prio)
-		TRACE_FIELD(unsigned char, next_state, next_state)
-		TRACE_FIELD(unsigned int, next_cpu, next_cpu)
-	),
-	TP_RAW_FMT("%u:%u:%u  ==+ %u:%u:%u [%03u]")
-);
-
-TRACE_EVENT_FORMAT(context_switch, TRACE_CTX, ctx_switch_entry, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(unsigned int, prev_pid, prev_pid)
-		TRACE_FIELD(unsigned char, prev_prio, prev_prio)
-		TRACE_FIELD(unsigned char, prev_state, prev_state)
-		TRACE_FIELD(unsigned int, next_pid, next_pid)
-		TRACE_FIELD(unsigned char, next_prio, next_prio)
-		TRACE_FIELD(unsigned char, next_state, next_state)
-		TRACE_FIELD(unsigned int, next_cpu, next_cpu)
-	),
-	TP_RAW_FMT("%u:%u:%u  ==+ %u:%u:%u [%03u]")
-);
-
-TRACE_EVENT_FORMAT_NOFILTER(special, TRACE_SPECIAL, special_entry, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(unsigned long, arg1, arg1)
-		TRACE_FIELD(unsigned long, arg2, arg2)
-		TRACE_FIELD(unsigned long, arg3, arg3)
-	),
-	TP_RAW_FMT("(%08lx) (%08lx) (%08lx)")
-);
-
-/*
- * Stack-trace entry:
- */
-
-/* #define FTRACE_STACK_ENTRIES   8 */
-
-TRACE_EVENT_FORMAT(kernel_stack, TRACE_STACK, stack_entry, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(unsigned long, caller[0], stack0)
-		TRACE_FIELD(unsigned long, caller[1], stack1)
-		TRACE_FIELD(unsigned long, caller[2], stack2)
-		TRACE_FIELD(unsigned long, caller[3], stack3)
-		TRACE_FIELD(unsigned long, caller[4], stack4)
-		TRACE_FIELD(unsigned long, caller[5], stack5)
-		TRACE_FIELD(unsigned long, caller[6], stack6)
-		TRACE_FIELD(unsigned long, caller[7], stack7)
-	),
-	TP_RAW_FMT("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n"
-		 "\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n")
-);
-
-TRACE_EVENT_FORMAT(user_stack, TRACE_USER_STACK, userstack_entry, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(unsigned long, caller[0], stack0)
-		TRACE_FIELD(unsigned long, caller[1], stack1)
-		TRACE_FIELD(unsigned long, caller[2], stack2)
-		TRACE_FIELD(unsigned long, caller[3], stack3)
-		TRACE_FIELD(unsigned long, caller[4], stack4)
-		TRACE_FIELD(unsigned long, caller[5], stack5)
-		TRACE_FIELD(unsigned long, caller[6], stack6)
-		TRACE_FIELD(unsigned long, caller[7], stack7)
-	),
-	TP_RAW_FMT("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n"
-		 "\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n")
-);
-
-TRACE_EVENT_FORMAT(bprint, TRACE_BPRINT, bprint_entry, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(unsigned long, ip, ip)
-		TRACE_FIELD(char *, fmt, fmt)
-		TRACE_FIELD_ZERO(char, buf)
-	),
-	TP_RAW_FMT("%08lx (%d) fmt:%p %s")
-);
-
-TRACE_EVENT_FORMAT(print, TRACE_PRINT, print_entry, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(unsigned long, ip, ip)
-		TRACE_FIELD_ZERO(char, buf)
-	),
-	TP_RAW_FMT("%08lx (%d) fmt:%p %s")
-);
-
-TRACE_EVENT_FORMAT(branch, TRACE_BRANCH, trace_branch, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(unsigned int, line, line)
-		TRACE_FIELD_SPECIAL(char func[TRACE_FUNC_SIZE+1], func,
-				    TRACE_FUNC_SIZE+1, func)
-		TRACE_FIELD_SPECIAL(char file[TRACE_FUNC_SIZE+1], file,
-				    TRACE_FUNC_SIZE+1, file)
-		TRACE_FIELD(char, correct, correct)
-	),
-	TP_RAW_FMT("%u:%s:%s (%u)")
-);
-
-TRACE_EVENT_FORMAT(hw_branch, TRACE_HW_BRANCHES, hw_branch_entry, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(u64, from, from)
-		TRACE_FIELD(u64, to, to)
-	),
-	TP_RAW_FMT("from: %llx to: %llx")
-);
-
-TRACE_EVENT_FORMAT(power, TRACE_POWER, trace_power, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD_SIGN(ktime_t, state_data.stamp, stamp, 1)
-		TRACE_FIELD_SIGN(ktime_t, state_data.end, end, 1)
-		TRACE_FIELD(int, state_data.type, type)
-		TRACE_FIELD(int, state_data.state, state)
-	),
-	TP_RAW_FMT("%llx->%llx type:%u state:%u")
-);
-
-TRACE_EVENT_FORMAT(kmem_alloc, TRACE_KMEM_ALLOC, kmemtrace_alloc_entry, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(enum kmemtrace_type_id, type_id, type_id)
-		TRACE_FIELD(unsigned long, call_site, call_site)
-		TRACE_FIELD(const void *, ptr, ptr)
-		TRACE_FIELD(size_t, bytes_req, bytes_req)
-		TRACE_FIELD(size_t, bytes_alloc, bytes_alloc)
-		TRACE_FIELD(gfp_t, gfp_flags, gfp_flags)
-		TRACE_FIELD(int, node, node)
-	),
-	TP_RAW_FMT("type:%u call_site:%lx ptr:%p req:%lu alloc:%lu"
-		 " flags:%x node:%d")
-);
-
-TRACE_EVENT_FORMAT(kmem_free, TRACE_KMEM_FREE, kmemtrace_free_entry, ignore,
-	TRACE_STRUCT(
-		TRACE_FIELD(enum kmemtrace_type_id, type_id, type_id)
-		TRACE_FIELD(unsigned long, call_site, call_site)
-		TRACE_FIELD(const void *, ptr, ptr)
-	),
-	TP_RAW_FMT("type:%u call_site:%lx ptr:%p")
-);
-
-#undef TRACE_SYSTEM
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index f85b0f1..a4b7c9a 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -21,6 +21,7 @@
 
 #include "trace_output.h"
 
+#undef TRACE_SYSTEM
 #define TRACE_SYSTEM "TRACE_SYSTEM"
 
 DEFINE_MUTEX(event_mutex);
@@ -86,7 +87,7 @@ int trace_define_common_fields(struct ftrace_event_call *call)
 	__common_field(unsigned char, flags);
 	__common_field(unsigned char, preempt_count);
 	__common_field(int, pid);
-	__common_field(int, tgid);
+	__common_field(int, lock_depth);
 
 	return ret;
 }
@@ -226,11 +227,9 @@ static ssize_t
 ftrace_event_write(struct file *file, const char __user *ubuf,
 		   size_t cnt, loff_t *ppos)
 {
+	struct trace_parser parser;
 	size_t read = 0;
-	int i, set = 1;
 	ssize_t ret;
-	char *buf;
-	char ch;
 
 	if (!cnt || cnt < 0)
 		return 0;
@@ -239,60 +238,28 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
 	if (ret < 0)
 		return ret;
 
-	ret = get_user(ch, ubuf++);
-	if (ret)
-		return ret;
-	read++;
-	cnt--;
-
-	/* skip white space */
-	while (cnt && isspace(ch)) {
-		ret = get_user(ch, ubuf++);
-		if (ret)
-			return ret;
-		read++;
-		cnt--;
-	}
-
-	/* Only white space found? */
-	if (isspace(ch)) {
-		file->f_pos += read;
-		ret = read;
-		return ret;
-	}
-
-	buf = kmalloc(EVENT_BUF_SIZE+1, GFP_KERNEL);
-	if (!buf)
+	if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))
 		return -ENOMEM;
 
-	if (cnt > EVENT_BUF_SIZE)
-		cnt = EVENT_BUF_SIZE;
+	read = trace_get_user(&parser, ubuf, cnt, ppos);
+
+	if (trace_parser_loaded((&parser))) {
+		int set = 1;
 
-	i = 0;
-	while (cnt && !isspace(ch)) {
-		if (!i && ch == '!')
+		if (*parser.buffer == '!')
 			set = 0;
-		else
-			buf[i++] = ch;
 
-		ret = get_user(ch, ubuf++);
+		parser.buffer[parser.idx] = 0;
+
+		ret = ftrace_set_clr_event(parser.buffer + !set, set);
 		if (ret)
-			goto out_free;
-		read++;
-		cnt--;
+			goto out_put;
 	}
-	buf[i] = 0;
-
-	file->f_pos += read;
-
-	ret = ftrace_set_clr_event(buf, set);
-	if (ret)
-		goto out_free;
 
 	ret = read;
 
- out_free:
-	kfree(buf);
+ out_put:
+	trace_parser_put(&parser);
 
 	return ret;
 }
@@ -300,42 +267,32 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
 static void *
 t_next(struct seq_file *m, void *v, loff_t *pos)
 {
-	struct list_head *list = m->private;
-	struct ftrace_event_call *call;
+	struct ftrace_event_call *call = v;
 
 	(*pos)++;
 
-	for (;;) {
-		if (list == &ftrace_events)
-			return NULL;
-
-		call = list_entry(list, struct ftrace_event_call, list);
-
+	list_for_each_entry_continue(call, &ftrace_events, list) {
 		/*
 		 * The ftrace subsystem is for showing formats only.
 		 * They can not be enabled or disabled via the event files.
 		 */
 		if (call->regfunc)
-			break;
-
-		list = list->next;
+			return call;
 	}
 
-	m->private = list->next;
-
-	return call;
+	return NULL;
 }
 
 static void *t_start(struct seq_file *m, loff_t *pos)
 {
-	struct ftrace_event_call *call = NULL;
+	struct ftrace_event_call *call;
 	loff_t l;
 
 	mutex_lock(&event_mutex);
 
-	m->private = ftrace_events.next;
+	call = list_entry(&ftrace_events, struct ftrace_event_call, list);
 	for (l = 0; l <= *pos; ) {
-		call = t_next(m, NULL, &l);
+		call = t_next(m, call, &l);
 		if (!call)
 			break;
 	}
@@ -345,37 +302,28 @@ static void *t_start(struct seq_file *m, loff_t *pos)
 static void *
 s_next(struct seq_file *m, void *v, loff_t *pos)
 {
-	struct list_head *list = m->private;
-	struct ftrace_event_call *call;
+	struct ftrace_event_call *call = v;
 
 	(*pos)++;
 
- retry:
-	if (list == &ftrace_events)
-		return NULL;
-
-	call = list_entry(list, struct ftrace_event_call, list);
-
-	if (!call->enabled) {
-		list = list->next;
-		goto retry;
+	list_for_each_entry_continue(call, &ftrace_events, list) {
+		if (call->enabled)
+			return call;
 	}
 
-	m->private = list->next;
-
-	return call;
+	return NULL;
 }
 
 static void *s_start(struct seq_file *m, loff_t *pos)
 {
-	struct ftrace_event_call *call = NULL;
+	struct ftrace_event_call *call;
 	loff_t l;
 
 	mutex_lock(&event_mutex);
 
-	m->private = ftrace_events.next;
+	call = list_entry(&ftrace_events, struct ftrace_event_call, list);
 	for (l = 0; l <= *pos; ) {
-		call = s_next(m, NULL, &l);
+		call = s_next(m, call, &l);
 		if (!call)
 			break;
 	}
@@ -574,7 +522,7 @@ static int trace_write_header(struct trace_seq *s)
 				FIELD(unsigned char, flags),
 				FIELD(unsigned char, preempt_count),
 				FIELD(int, pid),
-				FIELD(int, tgid));
+				FIELD(int, lock_depth));
 }
 
 static ssize_t
@@ -1242,7 +1190,7 @@ static int trace_module_notify(struct notifier_block *self,
 }
 #endif /* CONFIG_MODULES */
 
-struct notifier_block trace_module_nb = {
+static struct notifier_block trace_module_nb = {
 	.notifier_call = trace_module_notify,
 	.priority = 0,
 };
@@ -1414,6 +1362,18 @@ static __init void event_trace_self_tests(void)
 		if (!call->regfunc)
 			continue;
 
+/*
+ * Testing syscall events here is pretty useless, but
+ * we still do it if configured. But this is time consuming.
+ * What we really need is a user thread to perform the
+ * syscalls as we test.
+ */
+#ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS
+		if (call->system &&
+		    strcmp(call->system, "syscalls") == 0)
+			continue;
+#endif
+
 		pr_info("Testing event %s: ", call->name);
 
 		/*
@@ -1487,7 +1447,7 @@ static __init void event_trace_self_tests(void)
 
 #ifdef CONFIG_FUNCTION_TRACER
 
-static DEFINE_PER_CPU(atomic_t, test_event_disable);
+static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable);
 
 static void
 function_test_events_call(unsigned long ip, unsigned long parent_ip)
@@ -1504,7 +1464,7 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip)
 	pc = preempt_count();
 	resched = ftrace_preempt_disable();
 	cpu = raw_smp_processor_id();
-	disabled = atomic_inc_return(&per_cpu(test_event_disable, cpu));
+	disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu));
 
 	if (disabled != 1)
 		goto out;
@@ -1523,7 +1483,7 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip)
 	trace_nowake_buffer_unlock_commit(buffer, event, flags, pc);
 
  out:
-	atomic_dec(&per_cpu(test_event_disable, cpu));
+	atomic_dec(&per_cpu(ftrace_test_event_disable, cpu));
 	ftrace_preempt_enable(resched);
 }
 
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 93660fb..2324578 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -121,6 +121,47 @@ struct filter_parse_state {
 	} operand;
 };
 
+#define DEFINE_COMPARISON_PRED(type)					\
+static int filter_pred_##type(struct filter_pred *pred, void *event,	\
+			      int val1, int val2)			\
+{									\
+	type *addr = (type *)(event + pred->offset);			\
+	type val = (type)pred->val;					\
+	int match = 0;							\
+									\
+	switch (pred->op) {						\
+	case OP_LT:							\
+		match = (*addr < val);					\
+		break;							\
+	case OP_LE:							\
+		match = (*addr <= val);					\
+		break;							\
+	case OP_GT:							\
+		match = (*addr > val);					\
+		break;							\
+	case OP_GE:							\
+		match = (*addr >= val);					\
+		break;							\
+	default:							\
+		break;							\
+	}								\
+									\
+	return match;							\
+}
+
+#define DEFINE_EQUALITY_PRED(size)					\
+static int filter_pred_##size(struct filter_pred *pred, void *event,	\
+			      int val1, int val2)			\
+{									\
+	u##size *addr = (u##size *)(event + pred->offset);		\
+	u##size val = (u##size)pred->val;				\
+	int match;							\
+									\
+	match = (val == *addr) ^ pred->not;				\
+									\
+	return match;							\
+}
+
 DEFINE_COMPARISON_PRED(s64);
 DEFINE_COMPARISON_PRED(u64);
 DEFINE_COMPARISON_PRED(s32);
diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c
index a79ef6f..ed7d480 100644
--- a/kernel/trace/trace_export.c
+++ b/kernel/trace/trace_export.c
@@ -15,147 +15,124 @@
 
 #include "trace_output.h"
 
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM	ftrace
 
-#undef TRACE_STRUCT
-#define TRACE_STRUCT(args...) args
+/* not needed for this file */
+#undef __field_struct
+#define __field_struct(type, item)
 
-extern void __bad_type_size(void);
+#undef __field
+#define __field(type, item)				type item;
 
-#undef TRACE_FIELD
-#define TRACE_FIELD(type, item, assign)					\
-	if (sizeof(type) != sizeof(field.item))				\
-		__bad_type_size();					\
+#undef __field_desc
+#define __field_desc(type, container, item)		type item;
+
+#undef __array
+#define __array(type, item, size)			type item[size];
+
+#undef __array_desc
+#define __array_desc(type, container, item, size)	type item[size];
+
+#undef __dynamic_array
+#define __dynamic_array(type, item)			type item[];
+
+#undef F_STRUCT
+#define F_STRUCT(args...)				args
+
+#undef F_printk
+#define F_printk(fmt, args...) fmt, args
+
+#undef FTRACE_ENTRY
+#define FTRACE_ENTRY(name, struct_name, id, tstruct, print)	\
+struct ____ftrace_##name {					\
+	tstruct							\
+};								\
+static void __used ____ftrace_check_##name(void)		\
+{								\
+	struct ____ftrace_##name *__entry = NULL;		\
+								\
+	/* force cmpile-time check on F_printk() */		\
+	printk(print);						\
+}
+
+#undef FTRACE_ENTRY_DUP
+#define FTRACE_ENTRY_DUP(name, struct_name, id, tstruct, print)	\
+	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
+
+#include "trace_entries.h"
+
+
+#undef __field
+#define __field(type, item)						\
 	ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"	\
-			       "offset:%u;\tsize:%u;\n",		\
-			       (unsigned int)offsetof(typeof(field), item), \
-			       (unsigned int)sizeof(field.item));	\
+			       "offset:%zu;\tsize:%zu;\n",		\
+			       offsetof(typeof(field), item),		\
+			       sizeof(field.item));			\
 	if (!ret)							\
 		return 0;
 
+#undef __field_desc
+#define __field_desc(type, container, item)				\
+	ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"	\
+			       "offset:%zu;\tsize:%zu;\n",		\
+			       offsetof(typeof(field), container.item),	\
+			       sizeof(field.container.item));		\
+	if (!ret)							\
+		return 0;
 
-#undef TRACE_FIELD_SPECIAL
-#define TRACE_FIELD_SPECIAL(type_item, item, len, cmd)			\
-	ret = trace_seq_printf(s, "\tfield special:" #type_item ";\t"	\
-			       "offset:%u;\tsize:%u;\n",		\
-			       (unsigned int)offsetof(typeof(field), item), \
-			       (unsigned int)sizeof(field.item));	\
+#undef __array
+#define __array(type, item, len)					\
+	ret = trace_seq_printf(s, "\tfield:" #type " " #item "[" #len "];\t" \
+			       "offset:%zu;\tsize:%zu;\n",		\
+			       offsetof(typeof(field), item),	\
+			       sizeof(field.item));		\
 	if (!ret)							\
 		return 0;
 
-#undef TRACE_FIELD_ZERO
-#define TRACE_FIELD_ZERO(type, item)					\
-	ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"	\
-			       "offset:%u;\tsize:0;\n",			\
-			       (unsigned int)offsetof(typeof(field), item)); \
+#undef __array_desc
+#define __array_desc(type, container, item, len)			\
+	ret = trace_seq_printf(s, "\tfield:" #type " " #item "[" #len "];\t" \
+			       "offset:%zu;\tsize:%zu;\n",		\
+			       offsetof(typeof(field), container.item),	\
+			       sizeof(field.container.item));		\
 	if (!ret)							\
 		return 0;
 
-#undef TRACE_FIELD_SIGN
-#define TRACE_FIELD_SIGN(type, item, assign, is_signed)	\
-	TRACE_FIELD(type, item, assign)
+#undef __dynamic_array
+#define __dynamic_array(type, item)					\
+	ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"	\
+			       "offset:%zu;\tsize:0;\n",		\
+			       offsetof(typeof(field), item));		\
+	if (!ret)							\
+		return 0;
 
-#undef TP_RAW_FMT
-#define TP_RAW_FMT(args...) args
+#undef F_printk
+#define F_printk(fmt, args...) "%s, %s\n", #fmt, __stringify(args)
 
-#undef TRACE_EVENT_FORMAT
-#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)	\
-static int								\
-ftrace_format_##call(struct ftrace_event_call *unused,			\
-		      struct trace_seq *s)				\
-{									\
-	struct args field;						\
-	int ret;							\
-									\
-	tstruct;							\
-									\
-	trace_seq_printf(s, "\nprint fmt: \"%s\"\n", tpfmt);		\
-									\
-	return ret;							\
-}
+#undef __entry
+#define __entry REC
 
-#undef TRACE_EVENT_FORMAT_NOFILTER
-#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct,	\
-				    tpfmt)				\
+#undef FTRACE_ENTRY
+#define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
 static int								\
-ftrace_format_##call(struct ftrace_event_call *unused,			\
-		      struct trace_seq *s)				\
+ftrace_format_##name(struct ftrace_event_call *unused,			\
+		     struct trace_seq *s)				\
 {									\
-	struct args field;						\
-	int ret;							\
+	struct struct_name field __attribute__((unused));		\
+	int ret = 0;							\
 									\
 	tstruct;							\
 									\
-	trace_seq_printf(s, "\nprint fmt: \"%s\"\n", tpfmt);		\
+	trace_seq_printf(s, "\nprint fmt: " print);			\
 									\
 	return ret;							\
 }
 
-#include "trace_event_types.h"
-
-#undef TRACE_FIELD
-#define TRACE_FIELD(type, item, assign)\
-	entry->item = assign;
-
-#undef TRACE_FIELD
-#define TRACE_FIELD(type, item, assign)\
-	entry->item = assign;
-
-#undef TRACE_FIELD_SIGN
-#define TRACE_FIELD_SIGN(type, item, assign, is_signed)	\
-	TRACE_FIELD(type, item, assign)
-
-#undef TRACE_FIELD_ZERO
-#define TRACE_FIELD_ZERO(type, item)
-
-#undef TP_CMD
-#define TP_CMD(cmd...)	cmd
-
-#undef TRACE_ENTRY
-#define TRACE_ENTRY	entry
-
-#undef TRACE_FIELD_SPECIAL
-#define TRACE_FIELD_SPECIAL(type_item, item, len, cmd)	\
-	cmd;
-
-static int ftrace_raw_init_event(struct ftrace_event_call *event_call)
-{
-	INIT_LIST_HEAD(&event_call->fields);
-
-	return 0;
-}
-
-#undef TRACE_EVENT_FORMAT
-#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)	\
-int ftrace_define_fields_##call(struct ftrace_event_call *event_call);	\
-									\
-struct ftrace_event_call __used						\
-__attribute__((__aligned__(4)))						\
-__attribute__((section("_ftrace_events"))) event_##call = {		\
-	.name			= #call,				\
-	.id			= proto,				\
-	.system			= __stringify(TRACE_SYSTEM),		\
-	.raw_init		= ftrace_raw_init_event,		\
-	.show_format		= ftrace_format_##call,			\
-	.define_fields		= ftrace_define_fields_##call,		\
-};									\
-
-#undef TRACE_EVENT_FORMAT_NOFILTER
-#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct,	\
-				    tpfmt)				\
-									\
-struct ftrace_event_call __used						\
-__attribute__((__aligned__(4)))						\
-__attribute__((section("_ftrace_events"))) event_##call = {		\
-	.name			= #call,				\
-	.id			= proto,				\
-	.system			= __stringify(TRACE_SYSTEM),		\
-	.show_format		= ftrace_format_##call,			\
-};
-
-#include "trace_event_types.h"
+#include "trace_entries.h"
 
-#undef TRACE_FIELD
-#define TRACE_FIELD(type, item, assign)					\
+#undef __field
+#define __field(type, item)						\
 	ret = trace_define_field(event_call, #type, #item,		\
 				 offsetof(typeof(field), item),		\
 				 sizeof(field.item),			\
@@ -163,32 +140,45 @@ __attribute__((section("_ftrace_events"))) event_##call = {		\
 	if (ret)							\
 		return ret;
 
-#undef TRACE_FIELD_SPECIAL
-#define TRACE_FIELD_SPECIAL(type, item, len, cmd)			\
+#undef __field_desc
+#define __field_desc(type, container, item)	\
+	ret = trace_define_field(event_call, #type, #item,		\
+				 offsetof(typeof(field),		\
+					  container.item),		\
+				 sizeof(field.container.item),		\
+				 is_signed_type(type), FILTER_OTHER);	\
+	if (ret)							\
+		return ret;
+
+#undef __array
+#define __array(type, item, len)					\
+	BUILD_BUG_ON(len > MAX_FILTER_STR_VAL);				\
 	ret = trace_define_field(event_call, #type "[" #len "]", #item,	\
 				 offsetof(typeof(field), item),		\
 				 sizeof(field.item), 0, FILTER_OTHER);	\
 	if (ret)							\
 		return ret;
 
-#undef TRACE_FIELD_SIGN
-#define TRACE_FIELD_SIGN(type, item, assign, is_signed)			\
-	ret = trace_define_field(event_call, #type, #item,		\
-				 offsetof(typeof(field), item),		\
-				 sizeof(field.item), is_signed,		\
+#undef __array_desc
+#define __array_desc(type, container, item, len)			\
+	BUILD_BUG_ON(len > MAX_FILTER_STR_VAL);				\
+	ret = trace_define_field(event_call, #type "[" #len "]", #item,	\
+				 offsetof(typeof(field),		\
+					  container.item),		\
+				 sizeof(field.container.item), 0,	\
 				 FILTER_OTHER);				\
 	if (ret)							\
 		return ret;
 
-#undef TRACE_FIELD_ZERO
-#define TRACE_FIELD_ZERO(type, item)
+#undef __dynamic_array
+#define __dynamic_array(type, item)
 
-#undef TRACE_EVENT_FORMAT
-#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)	\
+#undef FTRACE_ENTRY
+#define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
 int									\
-ftrace_define_fields_##call(struct ftrace_event_call *event_call)	\
+ftrace_define_fields_##name(struct ftrace_event_call *event_call)	\
 {									\
-	struct args field;						\
+	struct struct_name field;					\
 	int ret;							\
 									\
 	ret = trace_define_common_fields(event_call);			\
@@ -200,8 +190,41 @@ ftrace_define_fields_##call(struct ftrace_event_call *event_call)	\
 	return ret;							\
 }
 
-#undef TRACE_EVENT_FORMAT_NOFILTER
-#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct,	\
-				    tpfmt)
+#include "trace_entries.h"
+
+static int ftrace_raw_init_event(struct ftrace_event_call *call)
+{
+	INIT_LIST_HEAD(&call->fields);
+	return 0;
+}
+
+#undef __field
+#define __field(type, item)
+
+#undef __field_desc
+#define __field_desc(type, container, item)
+
+#undef __array
+#define __array(type, item, len)
+
+#undef __array_desc
+#define __array_desc(type, container, item, len)
+
+#undef __dynamic_array
+#define __dynamic_array(type, item)
+
+#undef FTRACE_ENTRY
+#define FTRACE_ENTRY(call, struct_name, type, tstruct, print)		\
+									\
+struct ftrace_event_call __used						\
+__attribute__((__aligned__(4)))						\
+__attribute__((section("_ftrace_events"))) event_##call = {		\
+	.name			= #call,				\
+	.id			= type,					\
+	.system			= __stringify(TRACE_SYSTEM),		\
+	.raw_init		= ftrace_raw_init_event,		\
+	.show_format		= ftrace_format_##call,			\
+	.define_fields		= ftrace_define_fields_##call,		\
+};									\
 
-#include "trace_event_types.h"
+#include "trace_entries.h"
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 5b01b94..b3f3776 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -290,7 +290,7 @@ ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
 {
 	long count = (long)data;
 
-	seq_printf(m, "%pf:", (void *)ip);
+	seq_printf(m, "%ps:", (void *)ip);
 
 	if (ops == &traceon_probe_ops)
 		seq_printf(m, "traceon");
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index b3749a2..45e6c01 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -124,7 +124,7 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret,
 	if (unlikely(current->ret_stack[index].fp != frame_pointer)) {
 		ftrace_graph_stop();
 		WARN(1, "Bad frame pointer: expected %lx, received %lx\n"
-		     "  from func %pF return to %lx\n",
+		     "  from func %ps return to %lx\n",
 		     current->ret_stack[index].fp,
 		     frame_pointer,
 		     (void *)current->ret_stack[index].func,
@@ -364,6 +364,15 @@ print_graph_proc(struct trace_seq *s, pid_t pid)
 }
 
 
+static enum print_line_t
+print_graph_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
+{
+	if (!trace_seq_putc(s, ' '))
+		return 0;
+
+	return trace_print_lat_fmt(s, entry);
+}
+
 /* If the pid changed since the last trace, output this event */
 static enum print_line_t
 verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data)
@@ -521,6 +530,7 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr,
 		if (ret == TRACE_TYPE_PARTIAL_LINE)
 			return TRACE_TYPE_PARTIAL_LINE;
 	}
+
 	/* Proc */
 	if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
 		ret = print_graph_proc(s, pid);
@@ -659,7 +669,7 @@ print_graph_entry_leaf(struct trace_iterator *iter,
 			return TRACE_TYPE_PARTIAL_LINE;
 	}
 
-	ret = trace_seq_printf(s, "%pf();\n", (void *)call->func);
+	ret = trace_seq_printf(s, "%ps();\n", (void *)call->func);
 	if (!ret)
 		return TRACE_TYPE_PARTIAL_LINE;
 
@@ -702,7 +712,7 @@ print_graph_entry_nested(struct trace_iterator *iter,
 			return TRACE_TYPE_PARTIAL_LINE;
 	}
 
-	ret = trace_seq_printf(s, "%pf() {\n", (void *)call->func);
+	ret = trace_seq_printf(s, "%ps() {\n", (void *)call->func);
 	if (!ret)
 		return TRACE_TYPE_PARTIAL_LINE;
 
@@ -758,6 +768,13 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s,
 			return TRACE_TYPE_PARTIAL_LINE;
 	}
 
+	/* Latency format */
+	if (trace_flags & TRACE_ITER_LATENCY_FMT) {
+		ret = print_graph_lat_fmt(s, ent);
+		if (ret == TRACE_TYPE_PARTIAL_LINE)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
 	return 0;
 }
 
@@ -952,28 +969,59 @@ print_graph_function(struct trace_iterator *iter)
 	return TRACE_TYPE_HANDLED;
 }
 
+static void print_lat_header(struct seq_file *s)
+{
+	static const char spaces[] = "                "	/* 16 spaces */
+		"    "					/* 4 spaces */
+		"                 ";			/* 17 spaces */
+	int size = 0;
+
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
+		size += 16;
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
+		size += 4;
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
+		size += 17;
+
+	seq_printf(s, "#%.*s  _-----=> irqs-off        \n", size, spaces);
+	seq_printf(s, "#%.*s / _----=> need-resched    \n", size, spaces);
+	seq_printf(s, "#%.*s| / _---=> hardirq/softirq \n", size, spaces);
+	seq_printf(s, "#%.*s|| / _--=> preempt-depth   \n", size, spaces);
+	seq_printf(s, "#%.*s||| / _-=> lock-depth      \n", size, spaces);
+	seq_printf(s, "#%.*s|||| /                     \n", size, spaces);
+}
+
 static void print_graph_headers(struct seq_file *s)
 {
+	int lat = trace_flags & TRACE_ITER_LATENCY_FMT;
+
+	if (lat)
+		print_lat_header(s);
+
 	/* 1st line */
-	seq_printf(s, "# ");
+	seq_printf(s, "#");
 	if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
 		seq_printf(s, "     TIME       ");
 	if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
-		seq_printf(s, "CPU");
+		seq_printf(s, " CPU");
 	if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
-		seq_printf(s, "  TASK/PID      ");
+		seq_printf(s, "  TASK/PID       ");
+	if (lat)
+		seq_printf(s, "|||||");
 	if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
 		seq_printf(s, "  DURATION   ");
 	seq_printf(s, "               FUNCTION CALLS\n");
 
 	/* 2nd line */
-	seq_printf(s, "# ");
+	seq_printf(s, "#");
 	if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
 		seq_printf(s, "      |         ");
 	if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
-		seq_printf(s, "|  ");
+		seq_printf(s, " |  ");
 	if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
-		seq_printf(s, "  |    |        ");
+		seq_printf(s, "   |    |        ");
+	if (lat)
+		seq_printf(s, "|||||");
 	if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
 		seq_printf(s, "   |   |      ");
 	seq_printf(s, "               |   |   |   |\n");
diff --git a/kernel/trace/trace_hw_branches.c b/kernel/trace/trace_hw_branches.c
index ca7d7c4..23b6385 100644
--- a/kernel/trace/trace_hw_branches.c
+++ b/kernel/trace/trace_hw_branches.c
@@ -155,7 +155,7 @@ static enum print_line_t bts_trace_print_line(struct trace_iterator *iter)
 		    seq_print_ip_sym(seq, it->from, symflags) &&
 		    trace_seq_printf(seq, "\n"))
 			return TRACE_TYPE_HANDLED;
-		return TRACE_TYPE_PARTIAL_LINE;;
+		return TRACE_TYPE_PARTIAL_LINE;
 	}
 	return TRACE_TYPE_UNHANDLED;
 }
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 5555b75..3aa7eaa 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -129,15 +129,10 @@ check_critical_timing(struct trace_array *tr,
 		      unsigned long parent_ip,
 		      int cpu)
 {
-	unsigned long latency, t0, t1;
 	cycle_t T0, T1, delta;
 	unsigned long flags;
 	int pc;
 
-	/*
-	 * usecs conversion is slow so we try to delay the conversion
-	 * as long as possible:
-	 */
 	T0 = data->preempt_timestamp;
 	T1 = ftrace_now(cpu);
 	delta = T1-T0;
@@ -157,18 +152,15 @@ check_critical_timing(struct trace_array *tr,
 
 	trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
 
-	latency = nsecs_to_usecs(delta);
-
 	if (data->critical_sequence != max_sequence)
 		goto out_unlock;
 
-	tracing_max_latency = delta;
-	t0 = nsecs_to_usecs(T0);
-	t1 = nsecs_to_usecs(T1);
-
 	data->critical_end = parent_ip;
 
-	update_max_tr_single(tr, current, cpu);
+	if (likely(!is_tracing_stopped())) {
+		tracing_max_latency = delta;
+		update_max_tr_single(tr, current, cpu);
+	}
 
 	max_sequence++;
 
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index f6821f1..09cba270 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -28,7 +28,7 @@
 #include <linux/string.h>
 #include <linux/ctype.h>
 #include <linux/ptrace.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
 
 #include "trace.h"
 #include "trace_output.h"
@@ -1176,7 +1176,7 @@ static __kprobes int kprobe_profile_func(struct kprobe *kp,
 		entry->ip = (unsigned long)kp->addr;
 		for (i = 0; i < tp->nr_args; i++)
 			entry->args[i] = call_fetch(&tp->args[i].fetch, regs);
-		perf_tpcounter_event(call->id, entry->ip, 1, entry, size);
+		perf_tp_event(call->id, entry->ip, 1, entry, size);
 	} while (0);
 	return 0;
 }
@@ -1213,7 +1213,7 @@ static __kprobes int kretprobe_profile_func(struct kretprobe_instance *ri,
 		entry->ret_ip = (unsigned long)ri->ret_addr;
 		for (i = 0; i < tp->nr_args; i++)
 			entry->args[i] = call_fetch(&tp->args[i].fetch, regs);
-		perf_tpcounter_event(call->id, entry->ret_ip, 1, entry, size);
+		perf_tp_event(call->id, entry->ret_ip, 1, entry, size);
 	} while (0);
 	return 0;
 }
@@ -1222,10 +1222,8 @@ static int probe_profile_enable(struct ftrace_event_call *call)
 {
 	struct trace_probe *tp = (struct trace_probe *)call->data;
 
-	if (atomic_inc_return(&call->profile_count))
-		return 0;
-
 	tp->flags |= TP_FLAG_PROFILE;
+
 	if (probe_is_return(tp))
 		return enable_kretprobe(&tp->rp);
 	else
@@ -1236,10 +1234,9 @@ static void probe_profile_disable(struct ftrace_event_call *call)
 {
 	struct trace_probe *tp = (struct trace_probe *)call->data;
 
-	if (atomic_add_negative(-1, &call->profile_count))
-		tp->flags &= ~TP_FLAG_PROFILE;
+	tp->flags &= ~TP_FLAG_PROFILE;
 
-	if (!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE))) {
+	if (!(tp->flags & TP_FLAG_TRACE)) {
 		if (probe_is_return(tp))
 			disable_kretprobe(&tp->rp);
 		else
diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c
index c4c9bbd..0acd834 100644
--- a/kernel/trace/trace_mmiotrace.c
+++ b/kernel/trace/trace_mmiotrace.c
@@ -307,6 +307,7 @@ static void __trace_mmiotrace_rw(struct trace_array *tr,
 				struct trace_array_cpu *data,
 				struct mmiotrace_rw *rw)
 {
+	struct ftrace_event_call *call = &event_mmiotrace_rw;
 	struct ring_buffer *buffer = tr->buffer;
 	struct ring_buffer_event *event;
 	struct trace_mmiotrace_rw *entry;
@@ -320,7 +321,9 @@ static void __trace_mmiotrace_rw(struct trace_array *tr,
 	}
 	entry	= ring_buffer_event_data(event);
 	entry->rw			= *rw;
-	trace_buffer_unlock_commit(buffer, event, 0, pc);
+
+	if (!filter_check_discard(call, entry, buffer, event))
+		trace_buffer_unlock_commit(buffer, event, 0, pc);
 }
 
 void mmio_trace_rw(struct mmiotrace_rw *rw)
@@ -334,6 +337,7 @@ static void __trace_mmiotrace_map(struct trace_array *tr,
 				struct trace_array_cpu *data,
 				struct mmiotrace_map *map)
 {
+	struct ftrace_event_call *call = &event_mmiotrace_map;
 	struct ring_buffer *buffer = tr->buffer;
 	struct ring_buffer_event *event;
 	struct trace_mmiotrace_map *entry;
@@ -347,7 +351,9 @@ static void __trace_mmiotrace_map(struct trace_array *tr,
 	}
 	entry	= ring_buffer_event_data(event);
 	entry->map			= *map;
-	trace_buffer_unlock_commit(buffer, event, 0, pc);
+
+	if (!filter_check_discard(call, entry, buffer, event))
+		trace_buffer_unlock_commit(buffer, event, 0, pc);
 }
 
 void mmio_trace_mapping(struct mmiotrace_map *map)
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index e0c2545..f572f44 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -407,7 +407,7 @@ seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
 		 * since individual threads might have already quit!
 		 */
 		rcu_read_lock();
-		task = find_task_by_vpid(entry->ent.tgid);
+		task = find_task_by_vpid(entry->tgid);
 		if (task)
 			mm = get_task_mm(task);
 		rcu_read_unlock();
@@ -460,18 +460,23 @@ seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
 	return ret;
 }
 
-static int
-lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
+/**
+ * trace_print_lat_fmt - print the irq, preempt and lockdep fields
+ * @s: trace seq struct to write to
+ * @entry: The trace entry field from the ring buffer
+ *
+ * Prints the generic fields of irqs off, in hard or softirq, preempt
+ * count and lock depth.
+ */
+int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 {
 	int hardirq, softirq;
-	char comm[TASK_COMM_LEN];
+	int ret;
 
-	trace_find_cmdline(entry->pid, comm);
 	hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
 	softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
 
-	if (!trace_seq_printf(s, "%8.8s-%-5d %3d%c%c%c",
-			      comm, entry->pid, cpu,
+	if (!trace_seq_printf(s, "%c%c%c",
 			      (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
 				(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ?
 				  'X' : '.',
@@ -481,9 +486,30 @@ lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
 				hardirq ? 'h' : softirq ? 's' : '.'))
 		return 0;
 
+	if (entry->lock_depth < 0)
+		ret = trace_seq_putc(s, '.');
+	else
+		ret = trace_seq_printf(s, "%d", entry->lock_depth);
+	if (!ret)
+		return 0;
+
 	if (entry->preempt_count)
 		return trace_seq_printf(s, "%x", entry->preempt_count);
-	return trace_seq_puts(s, ".");
+	return trace_seq_putc(s, '.');
+}
+
+static int
+lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
+{
+	char comm[TASK_COMM_LEN];
+
+	trace_find_cmdline(entry->pid, comm);
+
+	if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
+			      comm, entry->pid, cpu))
+		return 0;
+
+	return trace_print_lat_fmt(s, entry);
 }
 
 static unsigned long preempt_mark_thresh = 100;
diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h
index d38bec4..9d91c72 100644
--- a/kernel/trace/trace_output.h
+++ b/kernel/trace/trace_output.h
@@ -26,6 +26,8 @@ extern struct trace_event *ftrace_find_event(int type);
 
 extern enum print_line_t trace_nop_print(struct trace_iterator *iter,
 					 int flags);
+extern int
+trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry);
 
 /* used by module unregistering */
 extern int __unregister_ftrace_event(struct trace_event *event);
diff --git a/kernel/trace/trace_power.c b/kernel/trace/trace_power.c
deleted file mode 100644
index fe1a00f..0000000
--- a/kernel/trace/trace_power.c
+++ /dev/null
@@ -1,218 +0,0 @@
-/*
- * ring buffer based C-state tracer
- *
- * Arjan van de Ven <arjan@linux.intel.com>
- * Copyright (C) 2008 Intel Corporation
- *
- * Much is borrowed from trace_boot.c which is
- * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com>
- *
- */
-
-#include <linux/init.h>
-#include <linux/debugfs.h>
-#include <trace/power.h>
-#include <linux/kallsyms.h>
-#include <linux/module.h>
-
-#include "trace.h"
-#include "trace_output.h"
-
-static struct trace_array *power_trace;
-static int __read_mostly trace_power_enabled;
-
-static void probe_power_start(struct power_trace *it, unsigned int type,
-				unsigned int level)
-{
-	if (!trace_power_enabled)
-		return;
-
-	memset(it, 0, sizeof(struct power_trace));
-	it->state = level;
-	it->type = type;
-	it->stamp = ktime_get();
-}
-
-
-static void probe_power_end(struct power_trace *it)
-{
-	struct ftrace_event_call *call = &event_power;
-	struct ring_buffer_event *event;
-	struct ring_buffer *buffer;
-	struct trace_power *entry;
-	struct trace_array_cpu *data;
-	struct trace_array *tr = power_trace;
-
-	if (!trace_power_enabled)
-		return;
-
-	buffer = tr->buffer;
-
-	preempt_disable();
-	it->end = ktime_get();
-	data = tr->data[smp_processor_id()];
-
-	event = trace_buffer_lock_reserve(buffer, TRACE_POWER,
-					  sizeof(*entry), 0, 0);
-	if (!event)
-		goto out;
-	entry	= ring_buffer_event_data(event);
-	entry->state_data = *it;
-	if (!filter_check_discard(call, entry, buffer, event))
-		trace_buffer_unlock_commit(buffer, event, 0, 0);
- out:
-	preempt_enable();
-}
-
-static void probe_power_mark(struct power_trace *it, unsigned int type,
-				unsigned int level)
-{
-	struct ftrace_event_call *call = &event_power;
-	struct ring_buffer_event *event;
-	struct ring_buffer *buffer;
-	struct trace_power *entry;
-	struct trace_array_cpu *data;
-	struct trace_array *tr = power_trace;
-
-	if (!trace_power_enabled)
-		return;
-
-	buffer = tr->buffer;
-
-	memset(it, 0, sizeof(struct power_trace));
-	it->state = level;
-	it->type = type;
-	it->stamp = ktime_get();
-	preempt_disable();
-	it->end = it->stamp;
-	data = tr->data[smp_processor_id()];
-
-	event = trace_buffer_lock_reserve(buffer, TRACE_POWER,
-					  sizeof(*entry), 0, 0);
-	if (!event)
-		goto out;
-	entry	= ring_buffer_event_data(event);
-	entry->state_data = *it;
-	if (!filter_check_discard(call, entry, buffer, event))
-		trace_buffer_unlock_commit(buffer, event, 0, 0);
- out:
-	preempt_enable();
-}
-
-static int tracing_power_register(void)
-{
-	int ret;
-
-	ret = register_trace_power_start(probe_power_start);
-	if (ret) {
-		pr_info("power trace: Couldn't activate tracepoint"
-			" probe to trace_power_start\n");
-		return ret;
-	}
-	ret = register_trace_power_end(probe_power_end);
-	if (ret) {
-		pr_info("power trace: Couldn't activate tracepoint"
-			" probe to trace_power_end\n");
-		goto fail_start;
-	}
-	ret = register_trace_power_mark(probe_power_mark);
-	if (ret) {
-		pr_info("power trace: Couldn't activate tracepoint"
-			" probe to trace_power_mark\n");
-		goto fail_end;
-	}
-	return ret;
-fail_end:
-	unregister_trace_power_end(probe_power_end);
-fail_start:
-	unregister_trace_power_start(probe_power_start);
-	return ret;
-}
-
-static void start_power_trace(struct trace_array *tr)
-{
-	trace_power_enabled = 1;
-}
-
-static void stop_power_trace(struct trace_array *tr)
-{
-	trace_power_enabled = 0;
-}
-
-static void power_trace_reset(struct trace_array *tr)
-{
-	trace_power_enabled = 0;
-	unregister_trace_power_start(probe_power_start);
-	unregister_trace_power_end(probe_power_end);
-	unregister_trace_power_mark(probe_power_mark);
-}
-
-
-static int power_trace_init(struct trace_array *tr)
-{
-	power_trace = tr;
-
-	trace_power_enabled = 1;
-	tracing_power_register();
-
-	tracing_reset_online_cpus(tr);
-	return 0;
-}
-
-static enum print_line_t power_print_line(struct trace_iterator *iter)
-{
-	int ret = 0;
-	struct trace_entry *entry = iter->ent;
-	struct trace_power *field ;
-	struct power_trace *it;
-	struct trace_seq *s = &iter->seq;
-	struct timespec stamp;
-	struct timespec duration;
-
-	trace_assign_type(field, entry);
-	it = &field->state_data;
-	stamp = ktime_to_timespec(it->stamp);
-	duration = ktime_to_timespec(ktime_sub(it->end, it->stamp));
-
-	if (entry->type == TRACE_POWER) {
-		if (it->type == POWER_CSTATE)
-			ret = trace_seq_printf(s, "[%5ld.%09ld] CSTATE: Going to C%i on cpu %i for %ld.%09ld\n",
-					  stamp.tv_sec,
-					  stamp.tv_nsec,
-					  it->state, iter->cpu,
-					  duration.tv_sec,
-					  duration.tv_nsec);
-		if (it->type == POWER_PSTATE)
-			ret = trace_seq_printf(s, "[%5ld.%09ld] PSTATE: Going to P%i on cpu %i\n",
-					  stamp.tv_sec,
-					  stamp.tv_nsec,
-					  it->state, iter->cpu);
-		if (!ret)
-			return TRACE_TYPE_PARTIAL_LINE;
-		return TRACE_TYPE_HANDLED;
-	}
-	return TRACE_TYPE_UNHANDLED;
-}
-
-static void power_print_header(struct seq_file *s)
-{
-	seq_puts(s, "#   TIMESTAMP      STATE  EVENT\n");
-	seq_puts(s, "#       |            |      |\n");
-}
-
-static struct tracer power_tracer __read_mostly =
-{
-	.name		= "power",
-	.init		= power_trace_init,
-	.start		= start_power_trace,
-	.stop		= stop_power_trace,
-	.reset		= power_trace_reset,
-	.print_line	= power_print_line,
-	.print_header	= power_print_header,
-};
-
-static int init_power_trace(void)
-{
-	return register_tracer(&power_tracer);
-}
-device_initcall(init_power_trace);
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
index 687699d..2547d88 100644
--- a/kernel/trace/trace_printk.c
+++ b/kernel/trace/trace_printk.c
@@ -11,7 +11,6 @@
 #include <linux/ftrace.h>
 #include <linux/string.h>
 #include <linux/module.h>
-#include <linux/marker.h>
 #include <linux/mutex.h>
 #include <linux/ctype.h>
 #include <linux/list.h>
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index ad69f10..26185d7 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -24,6 +24,7 @@ static int __read_mostly	tracer_enabled;
 
 static struct task_struct	*wakeup_task;
 static int			wakeup_cpu;
+static int			wakeup_current_cpu;
 static unsigned			wakeup_prio = -1;
 static int			wakeup_rt;
 
@@ -56,33 +57,23 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip)
 	resched = ftrace_preempt_disable();
 
 	cpu = raw_smp_processor_id();
+	if (cpu != wakeup_current_cpu)
+		goto out_enable;
+
 	data = tr->data[cpu];
 	disabled = atomic_inc_return(&data->disabled);
 	if (unlikely(disabled != 1))
 		goto out;
 
 	local_irq_save(flags);
-	__raw_spin_lock(&wakeup_lock);
-
-	if (unlikely(!wakeup_task))
-		goto unlock;
-
-	/*
-	 * The task can't disappear because it needs to
-	 * wake up first, and we have the wakeup_lock.
-	 */
-	if (task_cpu(wakeup_task) != cpu)
-		goto unlock;
 
 	trace_function(tr, ip, parent_ip, flags, pc);
 
- unlock:
-	__raw_spin_unlock(&wakeup_lock);
 	local_irq_restore(flags);
 
  out:
 	atomic_dec(&data->disabled);
-
+ out_enable:
 	ftrace_preempt_enable(resched);
 }
 
@@ -107,11 +98,18 @@ static int report_latency(cycle_t delta)
 	return 1;
 }
 
+static void probe_wakeup_migrate_task(struct task_struct *task, int cpu)
+{
+	if (task != wakeup_task)
+		return;
+
+	wakeup_current_cpu = cpu;
+}
+
 static void notrace
 probe_wakeup_sched_switch(struct rq *rq, struct task_struct *prev,
 	struct task_struct *next)
 {
-	unsigned long latency = 0, t0 = 0, t1 = 0;
 	struct trace_array_cpu *data;
 	cycle_t T0, T1, delta;
 	unsigned long flags;
@@ -157,10 +155,6 @@ probe_wakeup_sched_switch(struct rq *rq, struct task_struct *prev,
 	trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, flags, pc);
 	tracing_sched_switch_trace(wakeup_trace, prev, next, flags, pc);
 
-	/*
-	 * usecs conversion is slow so we try to delay the conversion
-	 * as long as possible:
-	 */
 	T0 = data->preempt_timestamp;
 	T1 = ftrace_now(cpu);
 	delta = T1-T0;
@@ -168,13 +162,10 @@ probe_wakeup_sched_switch(struct rq *rq, struct task_struct *prev,
 	if (!report_latency(delta))
 		goto out_unlock;
 
-	latency = nsecs_to_usecs(delta);
-
-	tracing_max_latency = delta;
-	t0 = nsecs_to_usecs(T0);
-	t1 = nsecs_to_usecs(T1);
-
-	update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);
+	if (likely(!is_tracing_stopped())) {
+		tracing_max_latency = delta;
+		update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);
+	}
 
 out_unlock:
 	__wakeup_reset(wakeup_trace);
@@ -244,6 +235,7 @@ probe_wakeup(struct rq *rq, struct task_struct *p, int success)
 	__wakeup_reset(wakeup_trace);
 
 	wakeup_cpu = task_cpu(p);
+	wakeup_current_cpu = wakeup_cpu;
 	wakeup_prio = p->prio;
 
 	wakeup_task = p;
@@ -293,6 +285,13 @@ static void start_wakeup_tracer(struct trace_array *tr)
 		goto fail_deprobe_wake_new;
 	}
 
+	ret = register_trace_sched_migrate_task(probe_wakeup_migrate_task);
+	if (ret) {
+		pr_info("wakeup trace: Couldn't activate tracepoint"
+			" probe to kernel_sched_migrate_task\n");
+		return;
+	}
+
 	wakeup_reset(tr);
 
 	/*
@@ -325,6 +324,7 @@ static void stop_wakeup_tracer(struct trace_array *tr)
 	unregister_trace_sched_switch(probe_wakeup_sched_switch);
 	unregister_trace_sched_wakeup_new(probe_wakeup);
 	unregister_trace_sched_wakeup(probe_wakeup);
+	unregister_trace_sched_migrate_task(probe_wakeup_migrate_task);
 }
 
 static int __wakeup_tracer_init(struct trace_array *tr)
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index dfc55fe..1b050ab 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -2,7 +2,7 @@
 #include <trace/events/syscalls.h>
 #include <linux/kernel.h>
 #include <linux/ftrace.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
 #include <asm/syscall.h>
 
 #include "trace_output.h"
@@ -384,10 +384,13 @@ static int sys_prof_refcount_exit;
 
 static void prof_syscall_enter(struct pt_regs *regs, long id)
 {
-	struct syscall_trace_enter *rec;
 	struct syscall_metadata *sys_data;
+	struct syscall_trace_enter *rec;
+	unsigned long flags;
+	char *raw_data;
 	int syscall_nr;
 	int size;
+	int cpu;
 
 	syscall_nr = syscall_get_nr(current, regs);
 	if (!test_bit(syscall_nr, enabled_prof_enter_syscalls))
@@ -402,20 +405,38 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
 	size = ALIGN(size + sizeof(u32), sizeof(u64));
 	size -= sizeof(u32);
 
-	do {
-		char raw_data[size];
+	if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE,
+		      "profile buffer not large enough"))
+		return;
+
+	/* Protect the per cpu buffer, begin the rcu read side */
+	local_irq_save(flags);
 
-		/* zero the dead bytes from align to not leak stack to user */
-		*(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
+	cpu = smp_processor_id();
+
+	if (in_nmi())
+		raw_data = rcu_dereference(trace_profile_buf_nmi);
+	else
+		raw_data = rcu_dereference(trace_profile_buf);
+
+	if (!raw_data)
+		goto end;
 
-		rec = (struct syscall_trace_enter *) raw_data;
-		tracing_generic_entry_update(&rec->ent, 0, 0);
-		rec->ent.type = sys_data->enter_id;
-		rec->nr = syscall_nr;
-		syscall_get_arguments(current, regs, 0, sys_data->nb_args,
-				       (unsigned long *)&rec->args);
-		perf_tpcounter_event(sys_data->enter_id, 0, 1, rec, size);
-	} while(0);
+	raw_data = per_cpu_ptr(raw_data, cpu);
+
+	/* zero the dead bytes from align to not leak stack to user */
+	*(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
+
+	rec = (struct syscall_trace_enter *) raw_data;
+	tracing_generic_entry_update(&rec->ent, 0, 0);
+	rec->ent.type = sys_data->enter_id;
+	rec->nr = syscall_nr;
+	syscall_get_arguments(current, regs, 0, sys_data->nb_args,
+			       (unsigned long *)&rec->args);
+	perf_tp_event(sys_data->enter_id, 0, 1, rec, size);
+
+end:
+	local_irq_restore(flags);
 }
 
 int reg_prof_syscall_enter(char *name)
@@ -460,8 +481,12 @@ void unreg_prof_syscall_enter(char *name)
 static void prof_syscall_exit(struct pt_regs *regs, long ret)
 {
 	struct syscall_metadata *sys_data;
-	struct syscall_trace_exit rec;
+	struct syscall_trace_exit *rec;
+	unsigned long flags;
 	int syscall_nr;
+	char *raw_data;
+	int size;
+	int cpu;
 
 	syscall_nr = syscall_get_nr(current, regs);
 	if (!test_bit(syscall_nr, enabled_prof_exit_syscalls))
@@ -471,12 +496,46 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
 	if (!sys_data)
 		return;
 
-	tracing_generic_entry_update(&rec.ent, 0, 0);
-	rec.ent.type = sys_data->exit_id;
-	rec.nr = syscall_nr;
-	rec.ret = syscall_get_return_value(current, regs);
+	/* We can probably do that at build time */
+	size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64));
+	size -= sizeof(u32);
 
-	perf_tpcounter_event(sys_data->exit_id, 0, 1, &rec, sizeof(rec));
+	/*
+	 * Impossible, but be paranoid with the future
+	 * How to put this check outside runtime?
+	 */
+	if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE,
+		"exit event has grown above profile buffer size"))
+		return;
+
+	/* Protect the per cpu buffer, begin the rcu read side */
+	local_irq_save(flags);
+	cpu = smp_processor_id();
+
+	if (in_nmi())
+		raw_data = rcu_dereference(trace_profile_buf_nmi);
+	else
+		raw_data = rcu_dereference(trace_profile_buf);
+
+	if (!raw_data)
+		goto end;
+
+	raw_data = per_cpu_ptr(raw_data, cpu);
+
+	/* zero the dead bytes from align to not leak stack to user */
+	*(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
+
+	rec = (struct syscall_trace_exit *)raw_data;
+
+	tracing_generic_entry_update(&rec->ent, 0, 0);
+	rec->ent.type = sys_data->exit_id;
+	rec->nr = syscall_nr;
+	rec->ret = syscall_get_return_value(current, regs);
+
+	perf_tp_event(sys_data->exit_id, 0, 1, rec, size);
+
+end:
+	local_irq_restore(flags);
 }
 
 int reg_prof_syscall_exit(char *name)
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index 9489a0a..cc89be5 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -48,7 +48,7 @@ static struct hlist_head tracepoint_table[TRACEPOINT_TABLE_SIZE];
 
 /*
  * Note about RCU :
- * It is used to to delay the free of multiple probes array until a quiescent
+ * It is used to delay the free of multiple probes array until a quiescent
  * state is reached.
  * Tracepoint entries modifications are protected by the tracepoints_mutex.
  */
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 0668795..addfe2d 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -317,8 +317,6 @@ static int worker_thread(void *__cwq)
 	if (cwq->wq->freezeable)
 		set_freezable();
 
-	set_user_nice(current, -5);
-
 	for (;;) {
 		prepare_to_wait(&cwq->more_work, &wait, TASK_INTERRUPTIBLE);
 		if (!freezing(current) &&
@@ -600,7 +598,12 @@ static struct workqueue_struct *keventd_wq __read_mostly;
  * schedule_work - put work task in global workqueue
  * @work: job to be done
  *
- * This puts a job in the kernel-global workqueue.
+ * Returns zero if @work was already on the kernel-global workqueue and
+ * non-zero otherwise.
+ *
+ * This puts a job in the kernel-global workqueue if it was not already
+ * queued and leaves it in the same position on the kernel-global
+ * workqueue otherwise.
  */
 int schedule_work(struct work_struct *work)
 {