diff options
Diffstat (limited to 'kernel')
90 files changed, 5018 insertions, 3686 deletions
diff --git a/kernel/Makefile b/kernel/Makefile index e898c5b..f70396e 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -2,16 +2,15 @@ # Makefile for the linux kernel. # -obj-y = sched.o fork.o exec_domain.o panic.o printk.o \ +obj-y = fork.o exec_domain.o panic.o printk.o \ cpu.o exit.o itimer.o time.o softirq.o resource.o \ sysctl.o sysctl_binary.o capability.o ptrace.o timer.o user.o \ signal.o sys.o kmod.o workqueue.o pid.o \ rcupdate.o extable.o params.o posix-timers.o \ kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \ hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \ - notifier.o ksysfs.o sched_clock.o cred.o \ - async.o range.o -obj-y += groups.o + notifier.o ksysfs.o cred.o \ + async.o range.o groups.o ifdef CONFIG_FUNCTION_TRACER # Do not trace debug files and internal ftrace files @@ -20,10 +19,11 @@ CFLAGS_REMOVE_lockdep_proc.o = -pg CFLAGS_REMOVE_mutex-debug.o = -pg CFLAGS_REMOVE_rtmutex-debug.o = -pg CFLAGS_REMOVE_cgroup-debug.o = -pg -CFLAGS_REMOVE_sched_clock.o = -pg CFLAGS_REMOVE_irq_work.o = -pg endif +obj-y += sched/ + obj-$(CONFIG_FREEZER) += freezer.o obj-$(CONFIG_PROFILING) += profile.o obj-$(CONFIG_SYSCTL_SYSCALL_CHECK) += sysctl_check.o @@ -99,7 +99,6 @@ obj-$(CONFIG_TRACING) += trace/ obj-$(CONFIG_X86_DS) += trace/ obj-$(CONFIG_RING_BUFFER) += trace/ obj-$(CONFIG_TRACEPOINTS) += trace/ -obj-$(CONFIG_SMP) += sched_cpupri.o obj-$(CONFIG_IRQ_WORK) += irq_work.o obj-$(CONFIG_CPU_PM) += cpu_pm.o @@ -110,15 +109,6 @@ obj-$(CONFIG_PADATA) += padata.o obj-$(CONFIG_CRASH_DUMP) += crash_dump.o obj-$(CONFIG_JUMP_LABEL) += jump_label.o -ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER),y) -# According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is -# needed for x86 only. Why this used to be enabled for all architectures is beyond -# me. I suspect most platforms don't need this, but until we know that for sure -# I turn this off for IA-64 only. Andreas Schwab says it's also needed on m68k -# to get a correct value for the wait-channel (WCHAN in ps). --davidm -CFLAGS_sched.o := $(PROFILING) -fno-omit-frame-pointer -endif - $(obj)/configs.o: $(obj)/config_data.h # config_data.h contains the same information as ikconfig.h but gzipped. diff --git a/kernel/acct.c b/kernel/acct.c index fa7eb3d..02e6167 100644 --- a/kernel/acct.c +++ b/kernel/acct.c @@ -84,11 +84,10 @@ static void do_acct_process(struct bsd_acct_struct *acct, * the cache line to have the data after getting the lock. */ struct bsd_acct_struct { - volatile int active; - volatile int needcheck; + int active; + unsigned long needcheck; struct file *file; struct pid_namespace *ns; - struct timer_list timer; struct list_head list; }; @@ -96,15 +95,6 @@ static DEFINE_SPINLOCK(acct_lock); static LIST_HEAD(acct_list); /* - * Called whenever the timer says to check the free space. - */ -static void acct_timeout(unsigned long x) -{ - struct bsd_acct_struct *acct = (struct bsd_acct_struct *)x; - acct->needcheck = 1; -} - -/* * Check the amount of free space and suspend/resume accordingly. */ static int check_free_space(struct bsd_acct_struct *acct, struct file *file) @@ -112,12 +102,12 @@ static int check_free_space(struct bsd_acct_struct *acct, struct file *file) struct kstatfs sbuf; int res; int act; - sector_t resume; - sector_t suspend; + u64 resume; + u64 suspend; spin_lock(&acct_lock); res = acct->active; - if (!file || !acct->needcheck) + if (!file || time_is_before_jiffies(acct->needcheck)) goto out; spin_unlock(&acct_lock); @@ -127,8 +117,8 @@ static int check_free_space(struct bsd_acct_struct *acct, struct file *file) suspend = sbuf.f_blocks * SUSPEND; resume = sbuf.f_blocks * RESUME; - sector_div(suspend, 100); - sector_div(resume, 100); + do_div(suspend, 100); + do_div(resume, 100); if (sbuf.f_bavail <= suspend) act = -1; @@ -160,10 +150,7 @@ static int check_free_space(struct bsd_acct_struct *acct, struct file *file) } } - del_timer(&acct->timer); - acct->needcheck = 0; - acct->timer.expires = jiffies + ACCT_TIMEOUT*HZ; - add_timer(&acct->timer); + acct->needcheck = jiffies + ACCT_TIMEOUT*HZ; res = acct->active; out: spin_unlock(&acct_lock); @@ -185,9 +172,7 @@ static void acct_file_reopen(struct bsd_acct_struct *acct, struct file *file, if (acct->file) { old_acct = acct->file; old_ns = acct->ns; - del_timer(&acct->timer); acct->active = 0; - acct->needcheck = 0; acct->file = NULL; acct->ns = NULL; list_del(&acct->list); @@ -195,13 +180,9 @@ static void acct_file_reopen(struct bsd_acct_struct *acct, struct file *file, if (file) { acct->file = file; acct->ns = ns; - acct->needcheck = 0; + acct->needcheck = jiffies + ACCT_TIMEOUT*HZ; acct->active = 1; list_add(&acct->list, &acct_list); - /* It's been deleted if it was used before so this is safe */ - setup_timer(&acct->timer, acct_timeout, (unsigned long)acct); - acct->timer.expires = jiffies + ACCT_TIMEOUT*HZ; - add_timer(&acct->timer); } if (old_acct) { mnt_unpin(old_acct->f_path.mnt); @@ -334,7 +315,7 @@ void acct_auto_close(struct super_block *sb) spin_lock(&acct_lock); restart: list_for_each_entry(acct, &acct_list, list) - if (acct->file && acct->file->f_path.mnt->mnt_sb == sb) { + if (acct->file && acct->file->f_path.dentry->d_sb == sb) { acct_file_reopen(acct, NULL, NULL); goto restart; } @@ -348,7 +329,6 @@ void acct_exit_ns(struct pid_namespace *ns) if (acct == NULL) return; - del_timer_sync(&acct->timer); spin_lock(&acct_lock); if (acct->file != NULL) acct_file_reopen(acct, NULL, NULL); @@ -498,7 +478,7 @@ static void do_acct_process(struct bsd_acct_struct *acct, * Fill the accounting struct with the needed info as recorded * by the different kernel functions. */ - memset((caddr_t)&ac, 0, sizeof(acct_t)); + memset(&ac, 0, sizeof(acct_t)); ac.ac_version = ACCT_VERSION | ACCT_BYTEORDER; strlcpy(ac.ac_comm, current->comm, sizeof(ac.ac_comm)); @@ -613,8 +593,8 @@ void acct_collect(long exitcode, int group_dead) pacct->ac_flag |= ACORE; if (current->flags & PF_SIGNALED) pacct->ac_flag |= AXSIG; - pacct->ac_utime = cputime_add(pacct->ac_utime, current->utime); - pacct->ac_stime = cputime_add(pacct->ac_stime, current->stime); + pacct->ac_utime += current->utime; + pacct->ac_stime += current->stime; pacct->ac_minflt += current->min_flt; pacct->ac_majflt += current->maj_flt; spin_unlock_irq(¤t->sighand->siglock); diff --git a/kernel/async.c b/kernel/async.c index 80b74b88..bd0c168 100644 --- a/kernel/async.c +++ b/kernel/async.c @@ -78,8 +78,6 @@ static DECLARE_WAIT_QUEUE_HEAD(async_done); static atomic_t entry_count; -extern int initcall_debug; - /* * MUST be called with the lock held! diff --git a/kernel/audit.c b/kernel/audit.c index 09fae26..57e3f51 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -601,13 +601,13 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type) case AUDIT_TTY_SET: case AUDIT_TRIM: case AUDIT_MAKE_EQUIV: - if (security_netlink_recv(skb, CAP_AUDIT_CONTROL)) + if (!capable(CAP_AUDIT_CONTROL)) err = -EPERM; break; case AUDIT_USER: case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG: case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2: - if (security_netlink_recv(skb, CAP_AUDIT_WRITE)) + if (!capable(CAP_AUDIT_WRITE)) err = -EPERM; break; default: /* bad msg */ @@ -1260,12 +1260,13 @@ static void audit_log_vformat(struct audit_buffer *ab, const char *fmt, avail = audit_expand(ab, max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail)); if (!avail) - goto out; + goto out_va_end; len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args2); } - va_end(args2); if (len > 0) skb_put(skb, len); +out_va_end: + va_end(args2); out: return; } diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 47b7fc1..e7fe2b0 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -210,12 +210,12 @@ struct audit_context { struct { uid_t uid; gid_t gid; - mode_t mode; + umode_t mode; u32 osid; int has_perm; uid_t perm_uid; gid_t perm_gid; - mode_t perm_mode; + umode_t perm_mode; unsigned long qbytes; } ipc; struct { @@ -234,7 +234,7 @@ struct audit_context { } mq_sendrecv; struct { int oflag; - mode_t mode; + umode_t mode; struct mq_attr attr; } mq_open; struct { @@ -308,7 +308,7 @@ static int audit_match_perm(struct audit_context *ctx, int mask) static int audit_match_filetype(struct audit_context *ctx, int which) { unsigned index = which & ~S_IFMT; - mode_t mode = which & S_IFMT; + umode_t mode = which & S_IFMT; if (unlikely(!ctx)) return 0; @@ -1249,7 +1249,7 @@ static void show_special(struct audit_context *context, int *call_panic) case AUDIT_IPC: { u32 osid = context->ipc.osid; - audit_log_format(ab, "ouid=%u ogid=%u mode=%#o", + audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho", context->ipc.uid, context->ipc.gid, context->ipc.mode); if (osid) { char *ctx = NULL; @@ -1267,7 +1267,7 @@ static void show_special(struct audit_context *context, int *call_panic) ab = audit_log_start(context, GFP_KERNEL, AUDIT_IPC_SET_PERM); audit_log_format(ab, - "qbytes=%lx ouid=%u ogid=%u mode=%#o", + "qbytes=%lx ouid=%u ogid=%u mode=%#ho", context->ipc.qbytes, context->ipc.perm_uid, context->ipc.perm_gid, @@ -1278,7 +1278,7 @@ static void show_special(struct audit_context *context, int *call_panic) break; } case AUDIT_MQ_OPEN: { audit_log_format(ab, - "oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld " + "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld " "mq_msgsize=%ld mq_curmsgs=%ld", context->mq_open.oflag, context->mq_open.mode, context->mq_open.attr.mq_flags, @@ -1502,7 +1502,7 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts if (n->ino != (unsigned long)-1) { audit_log_format(ab, " inode=%lu" - " dev=%02x:%02x mode=%#o" + " dev=%02x:%02x mode=%#ho" " ouid=%u ogid=%u rdev=%02x:%02x", n->ino, MAJOR(n->dev), @@ -2160,7 +2160,7 @@ int audit_set_loginuid(struct task_struct *task, uid_t loginuid) * @attr: queue attributes * */ -void __audit_mq_open(int oflag, mode_t mode, struct mq_attr *attr) +void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr) { struct audit_context *context = current->audit_context; @@ -2260,7 +2260,7 @@ void __audit_ipc_obj(struct kern_ipc_perm *ipcp) * * Called only after audit_ipc_obj(). */ -void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode) +void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode) { struct audit_context *context = current->audit_context; diff --git a/kernel/capability.c b/kernel/capability.c index b463871..0fcf1c1 100644 --- a/kernel/capability.c +++ b/kernel/capability.c @@ -287,74 +287,84 @@ error: } /** - * has_capability - Does a task have a capability in init_user_ns + * has_ns_capability - Does a task have a capability in a specific user ns * @t: The task in question + * @ns: target user namespace * @cap: The capability to be tested for * * Return true if the specified task has the given superior capability - * currently in effect to the initial user namespace, false if not. + * currently in effect to the specified user namespace, false if not. * * Note that this does not set PF_SUPERPRIV on the task. */ -bool has_capability(struct task_struct *t, int cap) +bool has_ns_capability(struct task_struct *t, + struct user_namespace *ns, int cap) { - int ret = security_real_capable(t, &init_user_ns, cap); + int ret; + + rcu_read_lock(); + ret = security_capable(__task_cred(t), ns, cap); + rcu_read_unlock(); return (ret == 0); } /** - * has_capability - Does a task have a capability in a specific user ns + * has_capability - Does a task have a capability in init_user_ns * @t: The task in question - * @ns: target user namespace * @cap: The capability to be tested for * * Return true if the specified task has the given superior capability - * currently in effect to the specified user namespace, false if not. + * currently in effect to the initial user namespace, false if not. * * Note that this does not set PF_SUPERPRIV on the task. */ -bool has_ns_capability(struct task_struct *t, - struct user_namespace *ns, int cap) +bool has_capability(struct task_struct *t, int cap) { - int ret = security_real_capable(t, ns, cap); - - return (ret == 0); + return has_ns_capability(t, &init_user_ns, cap); } /** - * has_capability_noaudit - Does a task have a capability (unaudited) + * has_ns_capability_noaudit - Does a task have a capability (unaudited) + * in a specific user ns. * @t: The task in question + * @ns: target user namespace * @cap: The capability to be tested for * * Return true if the specified task has the given superior capability - * currently in effect to init_user_ns, false if not. Don't write an - * audit message for the check. + * currently in effect to the specified user namespace, false if not. + * Do not write an audit message for the check. * * Note that this does not set PF_SUPERPRIV on the task. */ -bool has_capability_noaudit(struct task_struct *t, int cap) +bool has_ns_capability_noaudit(struct task_struct *t, + struct user_namespace *ns, int cap) { - int ret = security_real_capable_noaudit(t, &init_user_ns, cap); + int ret; + + rcu_read_lock(); + ret = security_capable_noaudit(__task_cred(t), ns, cap); + rcu_read_unlock(); return (ret == 0); } /** - * capable - Determine if the current task has a superior capability in effect + * has_capability_noaudit - Does a task have a capability (unaudited) in the + * initial user ns + * @t: The task in question * @cap: The capability to be tested for * - * Return true if the current task has the given superior capability currently - * available for use, false if not. + * Return true if the specified task has the given superior capability + * currently in effect to init_user_ns, false if not. Don't write an + * audit message for the check. * - * This sets PF_SUPERPRIV on the task if the capability is available on the - * assumption that it's about to be used. + * Note that this does not set PF_SUPERPRIV on the task. */ -bool capable(int cap) +bool has_capability_noaudit(struct task_struct *t, int cap) { - return ns_capable(&init_user_ns, cap); + return has_ns_capability_noaudit(t, &init_user_ns, cap); } -EXPORT_SYMBOL(capable); /** * ns_capable - Determine if the current task has a superior capability in effect @@ -374,7 +384,7 @@ bool ns_capable(struct user_namespace *ns, int cap) BUG(); } - if (security_capable(ns, current_cred(), cap) == 0) { + if (has_ns_capability(current, ns, cap)) { current->flags |= PF_SUPERPRIV; return true; } @@ -383,18 +393,20 @@ bool ns_capable(struct user_namespace *ns, int cap) EXPORT_SYMBOL(ns_capable); /** - * task_ns_capable - Determine whether current task has a superior - * capability targeted at a specific task's user namespace. - * @t: The task whose user namespace is targeted. - * @cap: The capability in question. + * capable - Determine if the current task has a superior capability in effect + * @cap: The capability to be tested for + * + * Return true if the current task has the given superior capability currently + * available for use, false if not. * - * Return true if it does, false otherwise. + * This sets PF_SUPERPRIV on the task if the capability is available on the + * assumption that it's about to be used. */ -bool task_ns_capable(struct task_struct *t, int cap) +bool capable(int cap) { - return ns_capable(task_cred_xxx(t, user)->user_ns, cap); + return ns_capable(&init_user_ns, cap); } -EXPORT_SYMBOL(task_ns_capable); +EXPORT_SYMBOL(capable); /** * nsown_capable - Check superior capability to one's own user_ns diff --git a/kernel/cgroup.c b/kernel/cgroup.c index a184470..a5d3b53 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -63,7 +63,24 @@ #include <linux/atomic.h> +/* + * cgroup_mutex is the master lock. Any modification to cgroup or its + * hierarchy must be performed while holding it. + * + * cgroup_root_mutex nests inside cgroup_mutex and should be held to modify + * cgroupfs_root of any cgroup hierarchy - subsys list, flags, + * release_agent_path and so on. Modifying requires both cgroup_mutex and + * cgroup_root_mutex. Readers can acquire either of the two. This is to + * break the following locking order cycle. + * + * A. cgroup_mutex -> cred_guard_mutex -> s_type->i_mutex_key -> namespace_sem + * B. namespace_sem -> cgroup_mutex + * + * B happens only through cgroup_show_options() and using cgroup_root_mutex + * breaks it. + */ static DEFINE_MUTEX(cgroup_mutex); +static DEFINE_MUTEX(cgroup_root_mutex); /* * Generate an array of cgroup subsystem pointers. At boot time, this is @@ -760,7 +777,7 @@ EXPORT_SYMBOL_GPL(cgroup_unlock); * -> cgroup_mkdir. */ -static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, int mode); +static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode); static struct dentry *cgroup_lookup(struct inode *, struct dentry *, struct nameidata *); static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry); static int cgroup_populate_dir(struct cgroup *cgrp); @@ -775,7 +792,7 @@ static struct backing_dev_info cgroup_backing_dev_info = { static int alloc_css_id(struct cgroup_subsys *ss, struct cgroup *parent, struct cgroup *child); -static struct inode *cgroup_new_inode(mode_t mode, struct super_block *sb) +static struct inode *cgroup_new_inode(umode_t mode, struct super_block *sb) { struct inode *inode = new_inode(sb); @@ -921,7 +938,7 @@ static void cgroup_d_remove_dir(struct dentry *dentry) * * CGRP_WAIT_ON_RMDIR flag is set under cgroup's inode->i_mutex; */ -DECLARE_WAIT_QUEUE_HEAD(cgroup_rmdir_waitq); +static DECLARE_WAIT_QUEUE_HEAD(cgroup_rmdir_waitq); static void cgroup_wakeup_rmdir_waiter(struct cgroup *cgrp) { @@ -953,6 +970,7 @@ static int rebind_subsystems(struct cgroupfs_root *root, int i; BUG_ON(!mutex_is_locked(&cgroup_mutex)); + BUG_ON(!mutex_is_locked(&cgroup_root_mutex)); removed_bits = root->actual_subsys_bits & ~final_bits; added_bits = final_bits & ~root->actual_subsys_bits; @@ -1038,12 +1056,12 @@ static int rebind_subsystems(struct cgroupfs_root *root, return 0; } -static int cgroup_show_options(struct seq_file *seq, struct vfsmount *vfs) +static int cgroup_show_options(struct seq_file *seq, struct dentry *dentry) { - struct cgroupfs_root *root = vfs->mnt_sb->s_fs_info; + struct cgroupfs_root *root = dentry->d_sb->s_fs_info; struct cgroup_subsys *ss; - mutex_lock(&cgroup_mutex); + mutex_lock(&cgroup_root_mutex); for_each_subsys(root, ss) seq_printf(seq, ",%s", ss->name); if (test_bit(ROOT_NOPREFIX, &root->flags)) @@ -1054,7 +1072,7 @@ static int cgroup_show_options(struct seq_file *seq, struct vfsmount *vfs) seq_puts(seq, ",clone_children"); if (strlen(root->name)) seq_printf(seq, ",name=%s", root->name); - mutex_unlock(&cgroup_mutex); + mutex_unlock(&cgroup_root_mutex); return 0; } @@ -1175,10 +1193,10 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts) /* * If the 'all' option was specified select all the subsystems, - * otherwise 'all, 'none' and a subsystem name options were not - * specified, let's default to 'all' + * otherwise if 'none', 'name=' and a subsystem name options + * were not specified, let's default to 'all' */ - if (all_ss || (!all_ss && !one_ss && !opts->none)) { + if (all_ss || (!one_ss && !opts->none && !opts->name)) { for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) { struct cgroup_subsys *ss = subsys[i]; if (ss == NULL) @@ -1269,6 +1287,7 @@ static int cgroup_remount(struct super_block *sb, int *flags, char *data) mutex_lock(&cgrp->dentry->d_inode->i_mutex); mutex_lock(&cgroup_mutex); + mutex_lock(&cgroup_root_mutex); /* See what subsystems are wanted */ ret = parse_cgroupfs_options(data, &opts); @@ -1297,6 +1316,7 @@ static int cgroup_remount(struct super_block *sb, int *flags, char *data) out_unlock: kfree(opts.release_agent); kfree(opts.name); + mutex_unlock(&cgroup_root_mutex); mutex_unlock(&cgroup_mutex); mutex_unlock(&cgrp->dentry->d_inode->i_mutex); return ret; @@ -1481,6 +1501,7 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type, int ret = 0; struct super_block *sb; struct cgroupfs_root *new_root; + struct inode *inode; /* First find the desired set of subsystems */ mutex_lock(&cgroup_mutex); @@ -1514,7 +1535,6 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type, /* We used the new root structure, so this is a new hierarchy */ struct list_head tmp_cg_links; struct cgroup *root_cgrp = &root->top_cgroup; - struct inode *inode; struct cgroupfs_root *existing_root; const struct cred *cred; int i; @@ -1528,18 +1548,14 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type, mutex_lock(&inode->i_mutex); mutex_lock(&cgroup_mutex); + mutex_lock(&cgroup_root_mutex); - if (strlen(root->name)) { - /* Check for name clashes with existing mounts */ - for_each_active_root(existing_root) { - if (!strcmp(existing_root->name, root->name)) { - ret = -EBUSY; - mutex_unlock(&cgroup_mutex); - mutex_unlock(&inode->i_mutex); - goto drop_new_super; - } - } - } + /* Check for name clashes with existing mounts */ + ret = -EBUSY; + if (strlen(root->name)) + for_each_active_root(existing_root) + if (!strcmp(existing_root->name, root->name)) + goto unlock_drop; /* * We're accessing css_set_count without locking @@ -1549,18 +1565,13 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type, * have some link structures left over */ ret = allocate_cg_links(css_set_count, &tmp_cg_links); - if (ret) { - mutex_unlock(&cgroup_mutex); - mutex_unlock(&inode->i_mutex); - goto drop_new_super; - } + if (ret) + goto unlock_drop; ret = rebind_subsystems(root, root->subsys_bits); if (ret == -EBUSY) { - mutex_unlock(&cgroup_mutex); - mutex_unlock(&inode->i_mutex); free_cg_links(&tmp_cg_links); - goto drop_new_super; + goto unlock_drop; } /* * There must be no failure case after here, since rebinding @@ -1599,6 +1610,7 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type, cred = override_creds(&init_cred); cgroup_populate_dir(root_cgrp); revert_creds(cred); + mutex_unlock(&cgroup_root_mutex); mutex_unlock(&cgroup_mutex); mutex_unlock(&inode->i_mutex); } else { @@ -1615,6 +1627,10 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type, kfree(opts.name); return dget(sb->s_root); + unlock_drop: + mutex_unlock(&cgroup_root_mutex); + mutex_unlock(&cgroup_mutex); + mutex_unlock(&inode->i_mutex); drop_new_super: deactivate_locked_super(sb); drop_modules: @@ -1639,6 +1655,7 @@ static void cgroup_kill_sb(struct super_block *sb) { BUG_ON(!list_empty(&cgrp->sibling)); mutex_lock(&cgroup_mutex); + mutex_lock(&cgroup_root_mutex); /* Rebind all subsystems back to the default hierarchy */ ret = rebind_subsystems(root, 0); @@ -1664,6 +1681,7 @@ static void cgroup_kill_sb(struct super_block *sb) { root_count--; } + mutex_unlock(&cgroup_root_mutex); mutex_unlock(&cgroup_mutex); kill_litter_super(sb); @@ -1740,11 +1758,90 @@ int cgroup_path(const struct cgroup *cgrp, char *buf, int buflen) EXPORT_SYMBOL_GPL(cgroup_path); /* + * Control Group taskset + */ +struct task_and_cgroup { + struct task_struct *task; + struct cgroup *cgrp; +}; + +struct cgroup_taskset { + struct task_and_cgroup single; + struct flex_array *tc_array; + int tc_array_len; + int idx; + struct cgroup *cur_cgrp; +}; + +/** + * cgroup_taskset_first - reset taskset and return the first task + * @tset: taskset of interest + * + * @tset iteration is initialized and the first task is returned. + */ +struct task_struct *cgroup_taskset_first(struct cgroup_taskset *tset) +{ + if (tset->tc_array) { + tset->idx = 0; + return cgroup_taskset_next(tset); + } else { + tset->cur_cgrp = tset->single.cgrp; + return tset->single.task; + } +} +EXPORT_SYMBOL_GPL(cgroup_taskset_first); + +/** + * cgroup_taskset_next - iterate to the next task in taskset + * @tset: taskset of interest + * + * Return the next task in @tset. Iteration must have been initialized + * with cgroup_taskset_first(). + */ +struct task_struct *cgroup_taskset_next(struct cgroup_taskset *tset) +{ + struct task_and_cgroup *tc; + + if (!tset->tc_array || tset->idx >= tset->tc_array_len) + return NULL; + + tc = flex_array_get(tset->tc_array, tset->idx++); + tset->cur_cgrp = tc->cgrp; + return tc->task; +} +EXPORT_SYMBOL_GPL(cgroup_taskset_next); + +/** + * cgroup_taskset_cur_cgroup - return the matching cgroup for the current task + * @tset: taskset of interest + * + * Return the cgroup for the current (last returned) task of @tset. This + * function must be preceded by either cgroup_taskset_first() or + * cgroup_taskset_next(). + */ +struct cgroup *cgroup_taskset_cur_cgroup(struct cgroup_taskset *tset) +{ + return tset->cur_cgrp; +} +EXPORT_SYMBOL_GPL(cgroup_taskset_cur_cgroup); + +/** + * cgroup_taskset_size - return the number of tasks in taskset + * @tset: taskset of interest + */ +int cgroup_taskset_size(struct cgroup_taskset *tset) +{ + return tset->tc_array ? tset->tc_array_len : 1; +} +EXPORT_SYMBOL_GPL(cgroup_taskset_size); + + +/* * cgroup_task_migrate - move a task from one cgroup to another. * * 'guarantee' is set if the caller promises that a new css_set for the task * will already exist. If not set, this function might sleep, and can fail with - * -ENOMEM. Otherwise, it can only fail with -ESRCH. + * -ENOMEM. Must be called with cgroup_mutex and threadgroup locked. */ static int cgroup_task_migrate(struct cgroup *cgrp, struct cgroup *oldcgrp, struct task_struct *tsk, bool guarantee) @@ -1753,14 +1850,12 @@ static int cgroup_task_migrate(struct cgroup *cgrp, struct cgroup *oldcgrp, struct css_set *newcg; /* - * get old css_set. we need to take task_lock and refcount it, because - * an exiting task can change its css_set to init_css_set and drop its - * old one without taking cgroup_mutex. + * We are synchronized through threadgroup_lock() against PF_EXITING + * setting such that we can't race against cgroup_exit() changing the + * css_set to init_css_set and dropping the old one. */ - task_lock(tsk); + WARN_ON_ONCE(tsk->flags & PF_EXITING); oldcg = tsk->cgroups; - get_css_set(oldcg); - task_unlock(tsk); /* locate or allocate a new css_set for this task. */ if (guarantee) { @@ -1775,20 +1870,11 @@ static int cgroup_task_migrate(struct cgroup *cgrp, struct cgroup *oldcgrp, might_sleep(); /* find_css_set will give us newcg already referenced. */ newcg = find_css_set(oldcg, cgrp); - if (!newcg) { - put_css_set(oldcg); + if (!newcg) return -ENOMEM; - } } - put_css_set(oldcg); - /* if PF_EXITING is set, the tsk->cgroups pointer is no longer safe. */ task_lock(tsk); - if (tsk->flags & PF_EXITING) { - task_unlock(tsk); - put_css_set(newcg); - return -ESRCH; - } rcu_assign_pointer(tsk->cgroups, newcg); task_unlock(tsk); @@ -1814,8 +1900,8 @@ static int cgroup_task_migrate(struct cgroup *cgrp, struct cgroup *oldcgrp, * @cgrp: the cgroup the task is attaching to * @tsk: the task to be attached * - * Call holding cgroup_mutex. May take task_lock of - * the task 'tsk' during call. + * Call with cgroup_mutex and threadgroup locked. May take task_lock of + * @tsk during call. */ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk) { @@ -1823,15 +1909,23 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk) struct cgroup_subsys *ss, *failed_ss = NULL; struct cgroup *oldcgrp; struct cgroupfs_root *root = cgrp->root; + struct cgroup_taskset tset = { }; + + /* @tsk either already exited or can't exit until the end */ + if (tsk->flags & PF_EXITING) + return -ESRCH; /* Nothing to do if the task is already in that cgroup */ oldcgrp = task_cgroup_from_root(tsk, root); if (cgrp == oldcgrp) return 0; + tset.single.task = tsk; + tset.single.cgrp = oldcgrp; + for_each_subsys(root, ss) { if (ss->can_attach) { - retval = ss->can_attach(ss, cgrp, tsk); + retval = ss->can_attach(ss, cgrp, &tset); if (retval) { /* * Remember on which subsystem the can_attach() @@ -1843,13 +1937,6 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk) goto out; } } - if (ss->can_attach_task) { - retval = ss->can_attach_task(cgrp, tsk); - if (retval) { - failed_ss = ss; - goto out; - } - } } retval = cgroup_task_migrate(cgrp, oldcgrp, tsk, false); @@ -1857,12 +1944,8 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk) goto out; for_each_subsys(root, ss) { - if (ss->pre_attach) - ss->pre_attach(cgrp); - if (ss->attach_task) - ss->attach_task(cgrp, tsk); if (ss->attach) - ss->attach(ss, cgrp, oldcgrp, tsk); + ss->attach(ss, cgrp, &tset); } synchronize_rcu(); @@ -1884,7 +1967,7 @@ out: */ break; if (ss->cancel_attach) - ss->cancel_attach(ss, cgrp, tsk); + ss->cancel_attach(ss, cgrp, &tset); } } return retval; @@ -1935,23 +2018,17 @@ static bool css_set_check_fetched(struct cgroup *cgrp, read_lock(&css_set_lock); newcg = find_existing_css_set(cg, cgrp, template); - if (newcg) - get_css_set(newcg); read_unlock(&css_set_lock); /* doesn't exist at all? */ if (!newcg) return false; /* see if it's already in the list */ - list_for_each_entry(cg_entry, newcg_list, links) { - if (cg_entry->cg == newcg) { - put_css_set(newcg); + list_for_each_entry(cg_entry, newcg_list, links) + if (cg_entry->cg == newcg) return true; - } - } /* not found */ - put_css_set(newcg); return false; } @@ -1985,21 +2062,21 @@ static int css_set_prefetch(struct cgroup *cgrp, struct css_set *cg, * @cgrp: the cgroup to attach to * @leader: the threadgroup leader task_struct of the group to be attached * - * Call holding cgroup_mutex and the threadgroup_fork_lock of the leader. Will - * take task_lock of each thread in leader's threadgroup individually in turn. + * Call holding cgroup_mutex and the group_rwsem of the leader. Will take + * task_lock of each thread in leader's threadgroup individually in turn. */ -int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) +static int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) { int retval, i, group_size; struct cgroup_subsys *ss, *failed_ss = NULL; - bool cancel_failed_ss = false; /* guaranteed to be initialized later, but the compiler needs this */ - struct cgroup *oldcgrp = NULL; struct css_set *oldcg; struct cgroupfs_root *root = cgrp->root; /* threadgroup list cursor and array */ struct task_struct *tsk; + struct task_and_cgroup *tc; struct flex_array *group; + struct cgroup_taskset tset = { }; /* * we need to make sure we have css_sets for all the tasks we're * going to move -before- we actually start moving them, so that in @@ -2012,13 +2089,12 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) * step 0: in order to do expensive, possibly blocking operations for * every thread, we cannot iterate the thread group list, since it needs * rcu or tasklist locked. instead, build an array of all threads in the - * group - threadgroup_fork_lock prevents new threads from appearing, - * and if threads exit, this will just be an over-estimate. + * group - group_rwsem prevents new threads from appearing, and if + * threads exit, this will just be an over-estimate. */ group_size = get_nr_threads(leader); /* flex_array supports very large thread-groups better than kmalloc. */ - group = flex_array_alloc(sizeof(struct task_struct *), group_size, - GFP_KERNEL); + group = flex_array_alloc(sizeof(*tc), group_size, GFP_KERNEL); if (!group) return -ENOMEM; /* pre-allocate to guarantee space while iterating in rcu read-side. */ @@ -2040,49 +2116,53 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) retval = -EAGAIN; goto out_free_group_list; } - /* take a reference on each task in the group to go in the array. */ + tsk = leader; i = 0; do { + struct task_and_cgroup ent; + + /* @tsk either already exited or can't exit until the end */ + if (tsk->flags & PF_EXITING) + continue; + /* as per above, nr_threads may decrease, but not increase. */ BUG_ON(i >= group_size); - get_task_struct(tsk); /* * saying GFP_ATOMIC has no effect here because we did prealloc * earlier, but it's good form to communicate our expectations. */ - retval = flex_array_put_ptr(group, i, tsk, GFP_ATOMIC); + ent.task = tsk; + ent.cgrp = task_cgroup_from_root(tsk, root); + /* nothing to do if this task is already in the cgroup */ + if (ent.cgrp == cgrp) + continue; + retval = flex_array_put(group, i, &ent, GFP_ATOMIC); BUG_ON(retval != 0); i++; } while_each_thread(leader, tsk); /* remember the number of threads in the array for later. */ group_size = i; + tset.tc_array = group; + tset.tc_array_len = group_size; read_unlock(&tasklist_lock); + /* methods shouldn't be called if no task is actually migrating */ + retval = 0; + if (!group_size) + goto out_free_group_list; + /* * step 1: check that we can legitimately attach to the cgroup. */ for_each_subsys(root, ss) { if (ss->can_attach) { - retval = ss->can_attach(ss, cgrp, leader); + retval = ss->can_attach(ss, cgrp, &tset); if (retval) { failed_ss = ss; goto out_cancel_attach; } } - /* a callback to be run on every thread in the threadgroup. */ - if (ss->can_attach_task) { - /* run on each task in the threadgroup. */ - for (i = 0; i < group_size; i++) { - tsk = flex_array_get_ptr(group, i); - retval = ss->can_attach_task(cgrp, tsk); - if (retval) { - failed_ss = ss; - cancel_failed_ss = true; - goto out_cancel_attach; - } - } - } } /* @@ -2091,67 +2171,36 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) */ INIT_LIST_HEAD(&newcg_list); for (i = 0; i < group_size; i++) { - tsk = flex_array_get_ptr(group, i); - /* nothing to do if this task is already in the cgroup */ - oldcgrp = task_cgroup_from_root(tsk, root); - if (cgrp == oldcgrp) - continue; - /* get old css_set pointer */ - task_lock(tsk); - oldcg = tsk->cgroups; - get_css_set(oldcg); - task_unlock(tsk); - /* see if the new one for us is already in the list? */ - if (css_set_check_fetched(cgrp, tsk, oldcg, &newcg_list)) { - /* was already there, nothing to do. */ - put_css_set(oldcg); - } else { - /* we don't already have it. get new one. */ + tc = flex_array_get(group, i); + oldcg = tc->task->cgroups; + + /* if we don't already have it in the list get a new one */ + if (!css_set_check_fetched(cgrp, tc->task, oldcg, + &newcg_list)) { retval = css_set_prefetch(cgrp, oldcg, &newcg_list); - put_css_set(oldcg); if (retval) goto out_list_teardown; } } /* - * step 3: now that we're guaranteed success wrt the css_sets, proceed - * to move all tasks to the new cgroup, calling ss->attach_task for each - * one along the way. there are no failure cases after here, so this is - * the commit point. + * step 3: now that we're guaranteed success wrt the css_sets, + * proceed to move all tasks to the new cgroup. There are no + * failure cases after here, so this is the commit point. */ - for_each_subsys(root, ss) { - if (ss->pre_attach) - ss->pre_attach(cgrp); - } for (i = 0; i < group_size; i++) { - tsk = flex_array_get_ptr(group, i); - /* leave current thread as it is if it's already there */ - oldcgrp = task_cgroup_from_root(tsk, root); - if (cgrp == oldcgrp) - continue; - /* if the thread is PF_EXITING, it can just get skipped. */ - retval = cgroup_task_migrate(cgrp, oldcgrp, tsk, true); - if (retval == 0) { - /* attach each task to each subsystem */ - for_each_subsys(root, ss) { - if (ss->attach_task) - ss->attach_task(cgrp, tsk); - } - } else { - BUG_ON(retval != -ESRCH); - } + tc = flex_array_get(group, i); + retval = cgroup_task_migrate(cgrp, tc->cgrp, tc->task, true); + BUG_ON(retval); } /* nothing is sensitive to fork() after this point. */ /* - * step 4: do expensive, non-thread-specific subsystem callbacks. - * TODO: if ever a subsystem needs to know the oldcgrp for each task - * being moved, this call will need to be reworked to communicate that. + * step 4: do subsystem attach callbacks. */ for_each_subsys(root, ss) { if (ss->attach) - ss->attach(ss, cgrp, oldcgrp, leader); + ss->attach(ss, cgrp, &tset); } /* @@ -2171,20 +2220,12 @@ out_cancel_attach: /* same deal as in cgroup_attach_task */ if (retval) { for_each_subsys(root, ss) { - if (ss == failed_ss) { - if (cancel_failed_ss && ss->cancel_attach) - ss->cancel_attach(ss, cgrp, leader); + if (ss == failed_ss) break; - } if (ss->cancel_attach) - ss->cancel_attach(ss, cgrp, leader); + ss->cancel_attach(ss, cgrp, &tset); } } - /* clean up the array of referenced threads in the group. */ - for (i = 0; i < group_size; i++) { - tsk = flex_array_get_ptr(group, i); - put_task_struct(tsk); - } out_free_group_list: flex_array_free(group); return retval; @@ -2192,8 +2233,8 @@ out_free_group_list: /* * Find the task_struct of the task to attach by vpid and pass it along to the - * function to attach either it or all tasks in its threadgroup. Will take - * cgroup_mutex; may take task_lock of task. + * function to attach either it or all tasks in its threadgroup. Will lock + * cgroup_mutex and threadgroup; may take task_lock of task. */ static int attach_task_by_pid(struct cgroup *cgrp, u64 pid, bool threadgroup) { @@ -2220,13 +2261,7 @@ static int attach_task_by_pid(struct cgroup *cgrp, u64 pid, bool threadgroup) * detect it later. */ tsk = tsk->group_leader; - } else if (tsk->flags & PF_EXITING) { - /* optimization for the single-task-only case */ - rcu_read_unlock(); - cgroup_unlock(); - return -ESRCH; } - /* * even if we're attaching all tasks in the thread group, we * only need to check permissions on one of them. @@ -2249,13 +2284,15 @@ static int attach_task_by_pid(struct cgroup *cgrp, u64 pid, bool threadgroup) get_task_struct(tsk); } - if (threadgroup) { - threadgroup_fork_write_lock(tsk); + threadgroup_lock(tsk); + + if (threadgroup) ret = cgroup_attach_proc(cgrp, tsk); - threadgroup_fork_write_unlock(tsk); - } else { + else ret = cgroup_attach_task(cgrp, tsk); - } + + threadgroup_unlock(tsk); + put_task_struct(tsk); cgroup_unlock(); return ret; @@ -2306,7 +2343,9 @@ static int cgroup_release_agent_write(struct cgroup *cgrp, struct cftype *cft, return -EINVAL; if (!cgroup_lock_live_group(cgrp)) return -ENODEV; + mutex_lock(&cgroup_root_mutex); strcpy(cgrp->root->release_agent_path, buffer); + mutex_unlock(&cgroup_root_mutex); cgroup_unlock(); return 0; } @@ -2585,7 +2624,7 @@ static inline struct cftype *__file_cft(struct file *file) return __d_cft(file->f_dentry); } -static int cgroup_create_file(struct dentry *dentry, mode_t mode, +static int cgroup_create_file(struct dentry *dentry, umode_t mode, struct super_block *sb) { struct inode *inode; @@ -2626,7 +2665,7 @@ static int cgroup_create_file(struct dentry *dentry, mode_t mode, * @mode: mode to set on new directory. */ static int cgroup_create_dir(struct cgroup *cgrp, struct dentry *dentry, - mode_t mode) + umode_t mode) { struct dentry *parent; int error = 0; @@ -2653,9 +2692,9 @@ static int cgroup_create_dir(struct cgroup *cgrp, struct dentry *dentry, * returns S_IRUGO if it has only a read handler * returns S_IWUSR if it has only a write hander */ -static mode_t cgroup_file_mode(const struct cftype *cft) +static umode_t cgroup_file_mode(const struct cftype *cft) { - mode_t mode = 0; + umode_t mode = 0; if (cft->mode) return cft->mode; @@ -2678,7 +2717,7 @@ int cgroup_add_file(struct cgroup *cgrp, struct dentry *dir = cgrp->dentry; struct dentry *dentry; int error; - mode_t mode; + umode_t mode; char name[MAX_CGROUP_TYPE_NAMELEN + MAX_CFTYPE_NAME + 2] = { 0 }; if (subsys && !test_bit(ROOT_NOPREFIX, &cgrp->root->flags)) { @@ -2789,6 +2828,7 @@ static void cgroup_enable_task_cg_lists(void) } void cgroup_iter_start(struct cgroup *cgrp, struct cgroup_iter *it) + __acquires(css_set_lock) { /* * The first time anyone tries to iterate across a cgroup, @@ -2828,6 +2868,7 @@ struct task_struct *cgroup_iter_next(struct cgroup *cgrp, } void cgroup_iter_end(struct cgroup *cgrp, struct cgroup_iter *it) + __releases(css_set_lock) { read_unlock(&css_set_lock); } @@ -3752,7 +3793,7 @@ static void cgroup_unlock_hierarchy(struct cgroupfs_root *root) * Must be called with the mutex on the parent inode held */ static long cgroup_create(struct cgroup *parent, struct dentry *dentry, - mode_t mode) + umode_t mode) { struct cgroup *cgrp; struct cgroupfs_root *root = parent->root; @@ -3846,7 +3887,7 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry, return err; } -static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, int mode) +static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) { struct cgroup *c_parent = dentry->d_parent->d_fsdata; @@ -4491,20 +4532,31 @@ static const struct file_operations proc_cgroupstats_operations = { * * A pointer to the shared css_set was automatically copied in * fork.c by dup_task_struct(). However, we ignore that copy, since - * it was not made under the protection of RCU or cgroup_mutex, so - * might no longer be a valid cgroup pointer. cgroup_attach_task() might - * have already changed current->cgroups, allowing the previously - * referenced cgroup group to be removed and freed. + * it was not made under the protection of RCU, cgroup_mutex or + * threadgroup_change_begin(), so it might no longer be a valid + * cgroup pointer. cgroup_attach_task() might have already changed + * current->cgroups, allowing the previously referenced cgroup + * group to be removed and freed. + * + * Outside the pointer validity we also need to process the css_set + * inheritance between threadgoup_change_begin() and + * threadgoup_change_end(), this way there is no leak in any process + * wide migration performed by cgroup_attach_proc() that could otherwise + * miss a thread because it is too early or too late in the fork stage. * * At the point that cgroup_fork() is called, 'current' is the parent * task, and the passed argument 'child' points to the child task. */ void cgroup_fork(struct task_struct *child) { - task_lock(current); + /* + * We don't need to task_lock() current because current->cgroups + * can't be changed concurrently here. The parent obviously hasn't + * exited and called cgroup_exit(), and we are synchronized against + * cgroup migration through threadgroup_change_begin(). + */ child->cgroups = current->cgroups; get_css_set(child->cgroups); - task_unlock(current); INIT_LIST_HEAD(&child->cg_list); } @@ -4546,10 +4598,19 @@ void cgroup_post_fork(struct task_struct *child) { if (use_task_css_set_links) { write_lock(&css_set_lock); - task_lock(child); - if (list_empty(&child->cg_list)) + if (list_empty(&child->cg_list)) { + /* + * It's safe to use child->cgroups without task_lock() + * here because we are protected through + * threadgroup_change_begin() against concurrent + * css_set change in cgroup_task_migrate(). Also + * the task can't exit at that point until + * wake_up_new_task() is called, so we are protected + * against cgroup_exit() setting child->cgroup to + * init_css_set. + */ list_add(&child->cg_list, &child->cgroups->tasks); - task_unlock(child); + } write_unlock(&css_set_lock); } } diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c index 213c035..fc0646b 100644 --- a/kernel/cgroup_freezer.c +++ b/kernel/cgroup_freezer.c @@ -48,19 +48,17 @@ static inline struct freezer *task_freezer(struct task_struct *task) struct freezer, css); } -static inline int __cgroup_freezing_or_frozen(struct task_struct *task) +bool cgroup_freezing(struct task_struct *task) { - enum freezer_state state = task_freezer(task)->state; - return (state == CGROUP_FREEZING) || (state == CGROUP_FROZEN); -} + enum freezer_state state; + bool ret; -int cgroup_freezing_or_frozen(struct task_struct *task) -{ - int result; - task_lock(task); - result = __cgroup_freezing_or_frozen(task); - task_unlock(task); - return result; + rcu_read_lock(); + state = task_freezer(task)->state; + ret = state == CGROUP_FREEZING || state == CGROUP_FROZEN; + rcu_read_unlock(); + + return ret; } /* @@ -102,9 +100,6 @@ struct cgroup_subsys freezer_subsys; * freezer_can_attach(): * cgroup_mutex (held by caller of can_attach) * - * cgroup_freezing_or_frozen(): - * task->alloc_lock (to get task's cgroup) - * * freezer_fork() (preserving fork() performance means can't take cgroup_mutex): * freezer->lock * sighand->siglock (if the cgroup is freezing) @@ -130,7 +125,7 @@ struct cgroup_subsys freezer_subsys; * write_lock css_set_lock (cgroup iterator start) * task->alloc_lock * read_lock css_set_lock (cgroup iterator start) - * task->alloc_lock (inside thaw_process(), prevents race with refrigerator()) + * task->alloc_lock (inside __thaw_task(), prevents race with refrigerator()) * sighand->siglock */ static struct cgroup_subsys_state *freezer_create(struct cgroup_subsys *ss, @@ -150,7 +145,11 @@ static struct cgroup_subsys_state *freezer_create(struct cgroup_subsys *ss, static void freezer_destroy(struct cgroup_subsys *ss, struct cgroup *cgroup) { - kfree(cgroup_freezer(cgroup)); + struct freezer *freezer = cgroup_freezer(cgroup); + + if (freezer->state != CGROUP_THAWED) + atomic_dec(&system_freezing_cnt); + kfree(freezer); } /* task is frozen or will freeze immediately when next it gets woken */ @@ -167,13 +166,17 @@ static bool is_task_frozen_enough(struct task_struct *task) */ static int freezer_can_attach(struct cgroup_subsys *ss, struct cgroup *new_cgroup, - struct task_struct *task) + struct cgroup_taskset *tset) { struct freezer *freezer; + struct task_struct *task; /* * Anything frozen can't move or be moved to/from. */ + cgroup_taskset_for_each(task, new_cgroup, tset) + if (cgroup_freezing(task)) + return -EBUSY; freezer = cgroup_freezer(new_cgroup); if (freezer->state != CGROUP_THAWED) @@ -182,17 +185,6 @@ static int freezer_can_attach(struct cgroup_subsys *ss, return 0; } -static int freezer_can_attach_task(struct cgroup *cgrp, struct task_struct *tsk) -{ - rcu_read_lock(); - if (__cgroup_freezing_or_frozen(tsk)) { - rcu_read_unlock(); - return -EBUSY; - } - rcu_read_unlock(); - return 0; -} - static void freezer_fork(struct cgroup_subsys *ss, struct task_struct *task) { struct freezer *freezer; @@ -220,7 +212,7 @@ static void freezer_fork(struct cgroup_subsys *ss, struct task_struct *task) /* Locking avoids race with FREEZING -> THAWED transitions. */ if (freezer->state == CGROUP_FREEZING) - freeze_task(task, true); + freeze_task(task); spin_unlock_irq(&freezer->lock); } @@ -238,7 +230,7 @@ static void update_if_frozen(struct cgroup *cgroup, cgroup_iter_start(cgroup, &it); while ((task = cgroup_iter_next(cgroup, &it))) { ntotal++; - if (is_task_frozen_enough(task)) + if (freezing(task) && is_task_frozen_enough(task)) nfrozen++; } @@ -286,10 +278,9 @@ static int try_to_freeze_cgroup(struct cgroup *cgroup, struct freezer *freezer) struct task_struct *task; unsigned int num_cant_freeze_now = 0; - freezer->state = CGROUP_FREEZING; cgroup_iter_start(cgroup, &it); while ((task = cgroup_iter_next(cgroup, &it))) { - if (!freeze_task(task, true)) + if (!freeze_task(task)) continue; if (is_task_frozen_enough(task)) continue; @@ -307,12 +298,9 @@ static void unfreeze_cgroup(struct cgroup *cgroup, struct freezer *freezer) struct task_struct *task; cgroup_iter_start(cgroup, &it); - while ((task = cgroup_iter_next(cgroup, &it))) { - thaw_process(task); - } + while ((task = cgroup_iter_next(cgroup, &it))) + __thaw_task(task); cgroup_iter_end(cgroup, &it); - - freezer->state = CGROUP_THAWED; } static int freezer_change_state(struct cgroup *cgroup, @@ -326,20 +314,24 @@ static int freezer_change_state(struct cgroup *cgroup, spin_lock_irq(&freezer->lock); update_if_frozen(cgroup, freezer); - if (goal_state == freezer->state) - goto out; switch (goal_state) { case CGROUP_THAWED: + if (freezer->state != CGROUP_THAWED) + atomic_dec(&system_freezing_cnt); + freezer->state = CGROUP_THAWED; unfreeze_cgroup(cgroup, freezer); break; case CGROUP_FROZEN: + if (freezer->state == CGROUP_THAWED) + atomic_inc(&system_freezing_cnt); + freezer->state = CGROUP_FREEZING; retval = try_to_freeze_cgroup(cgroup, freezer); break; default: BUG(); } -out: + spin_unlock_irq(&freezer->lock); return retval; @@ -388,10 +380,5 @@ struct cgroup_subsys freezer_subsys = { .populate = freezer_populate, .subsys_id = freezer_subsys_id, .can_attach = freezer_can_attach, - .can_attach_task = freezer_can_attach_task, - .pre_attach = NULL, - .attach_task = NULL, - .attach = NULL, .fork = freezer_fork, - .exit = NULL, }; diff --git a/kernel/cpu.c b/kernel/cpu.c index 563f136..2060c6e 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -178,8 +178,7 @@ static inline void check_for_tasks(int cpu) write_lock_irq(&tasklist_lock); for_each_process(p) { if (task_cpu(p) == cpu && p->state == TASK_RUNNING && - (!cputime_eq(p->utime, cputime_zero) || - !cputime_eq(p->stime, cputime_zero))) + (p->utime || p->stime)) printk(KERN_WARNING "Task %s (pid = %d) is on cpu %d " "(state = %ld, flags = %x)\n", p->comm, task_pid_nr(p), cpu, @@ -380,6 +379,7 @@ out: cpu_maps_update_done(); return err; } +EXPORT_SYMBOL_GPL(cpu_up); #ifdef CONFIG_PM_SLEEP_SMP static cpumask_var_t frozen_cpus; @@ -470,7 +470,7 @@ out: cpu_maps_update_done(); } -static int alloc_frozen_cpus(void) +static int __init alloc_frozen_cpus(void) { if (!alloc_cpumask_var(&frozen_cpus, GFP_KERNEL|__GFP_ZERO)) return -ENOMEM; @@ -543,7 +543,7 @@ cpu_hotplug_pm_callback(struct notifier_block *nb, } -int cpu_hotplug_pm_sync_init(void) +static int __init cpu_hotplug_pm_sync_init(void) { pm_notifier(cpu_hotplug_pm_callback, 0); return 0; diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 0b1712d..a09ac2b 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -1389,79 +1389,73 @@ static int fmeter_getrate(struct fmeter *fmp) return val; } -/* Called by cgroups to determine if a cpuset is usable; cgroup_mutex held */ -static int cpuset_can_attach(struct cgroup_subsys *ss, struct cgroup *cont, - struct task_struct *tsk) -{ - struct cpuset *cs = cgroup_cs(cont); - - if (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)) - return -ENOSPC; - - /* - * Kthreads bound to specific cpus cannot be moved to a new cpuset; we - * cannot change their cpu affinity and isolating such threads by their - * set of allowed nodes is unnecessary. Thus, cpusets are not - * applicable for such threads. This prevents checking for success of - * set_cpus_allowed_ptr() on all attached tasks before cpus_allowed may - * be changed. - */ - if (tsk->flags & PF_THREAD_BOUND) - return -EINVAL; - - return 0; -} - -static int cpuset_can_attach_task(struct cgroup *cgrp, struct task_struct *task) -{ - return security_task_setscheduler(task); -} - /* * Protected by cgroup_lock. The nodemasks must be stored globally because - * dynamically allocating them is not allowed in pre_attach, and they must - * persist among pre_attach, attach_task, and attach. + * dynamically allocating them is not allowed in can_attach, and they must + * persist until attach. */ static cpumask_var_t cpus_attach; static nodemask_t cpuset_attach_nodemask_from; static nodemask_t cpuset_attach_nodemask_to; -/* Set-up work for before attaching each task. */ -static void cpuset_pre_attach(struct cgroup *cont) +/* Called by cgroups to determine if a cpuset is usable; cgroup_mutex held */ +static int cpuset_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, + struct cgroup_taskset *tset) { - struct cpuset *cs = cgroup_cs(cont); + struct cpuset *cs = cgroup_cs(cgrp); + struct task_struct *task; + int ret; + + if (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)) + return -ENOSPC; + + cgroup_taskset_for_each(task, cgrp, tset) { + /* + * Kthreads bound to specific cpus cannot be moved to a new + * cpuset; we cannot change their cpu affinity and + * isolating such threads by their set of allowed nodes is + * unnecessary. Thus, cpusets are not applicable for such + * threads. This prevents checking for success of + * set_cpus_allowed_ptr() on all attached tasks before + * cpus_allowed may be changed. + */ + if (task->flags & PF_THREAD_BOUND) + return -EINVAL; + if ((ret = security_task_setscheduler(task))) + return ret; + } + /* prepare for attach */ if (cs == &top_cpuset) cpumask_copy(cpus_attach, cpu_possible_mask); else guarantee_online_cpus(cs, cpus_attach); guarantee_online_mems(cs, &cpuset_attach_nodemask_to); -} - -/* Per-thread attachment work. */ -static void cpuset_attach_task(struct cgroup *cont, struct task_struct *tsk) -{ - int err; - struct cpuset *cs = cgroup_cs(cont); - /* - * can_attach beforehand should guarantee that this doesn't fail. - * TODO: have a better way to handle failure here - */ - err = set_cpus_allowed_ptr(tsk, cpus_attach); - WARN_ON_ONCE(err); - - cpuset_change_task_nodemask(tsk, &cpuset_attach_nodemask_to); - cpuset_update_task_spread_flag(cs, tsk); + return 0; } -static void cpuset_attach(struct cgroup_subsys *ss, struct cgroup *cont, - struct cgroup *oldcont, struct task_struct *tsk) +static void cpuset_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, + struct cgroup_taskset *tset) { struct mm_struct *mm; - struct cpuset *cs = cgroup_cs(cont); - struct cpuset *oldcs = cgroup_cs(oldcont); + struct task_struct *task; + struct task_struct *leader = cgroup_taskset_first(tset); + struct cgroup *oldcgrp = cgroup_taskset_cur_cgroup(tset); + struct cpuset *cs = cgroup_cs(cgrp); + struct cpuset *oldcs = cgroup_cs(oldcgrp); + + cgroup_taskset_for_each(task, cgrp, tset) { + /* + * can_attach beforehand should guarantee that this doesn't + * fail. TODO: have a better way to handle failure here + */ + WARN_ON_ONCE(set_cpus_allowed_ptr(task, cpus_attach)); + + cpuset_change_task_nodemask(task, &cpuset_attach_nodemask_to); + cpuset_update_task_spread_flag(cs, task); + } /* * Change mm, possibly for multiple threads in a threadgroup. This is @@ -1469,7 +1463,7 @@ static void cpuset_attach(struct cgroup_subsys *ss, struct cgroup *cont, */ cpuset_attach_nodemask_from = oldcs->mems_allowed; cpuset_attach_nodemask_to = cs->mems_allowed; - mm = get_task_mm(tsk); + mm = get_task_mm(leader); if (mm) { mpol_rebind_mm(mm, &cpuset_attach_nodemask_to); if (is_memory_migrate(cs)) @@ -1925,9 +1919,6 @@ struct cgroup_subsys cpuset_subsys = { .create = cpuset_create, .destroy = cpuset_destroy, .can_attach = cpuset_can_attach, - .can_attach_task = cpuset_can_attach_task, - .pre_attach = cpuset_pre_attach, - .attach_task = cpuset_attach_task, .attach = cpuset_attach, .populate = cpuset_populate, .post_clone = cpuset_post_clone, diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index 63786e7..e2ae734 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -1982,7 +1982,7 @@ static int kdb_lsmod(int argc, const char **argv) kdb_printf("%-20s%8u 0x%p ", mod->name, mod->core_size, (void *)mod); #ifdef CONFIG_MODULE_UNLOAD - kdb_printf("%4d ", module_refcount(mod)); + kdb_printf("%4ld ", module_refcount(mod)); #endif if (mod->state == MODULE_STATE_GOING) kdb_printf(" (Unloading)"); diff --git a/kernel/debug/kdb/kdb_support.c b/kernel/debug/kdb/kdb_support.c index 5532dd3..7d6fb40 100644 --- a/kernel/debug/kdb/kdb_support.c +++ b/kernel/debug/kdb/kdb_support.c @@ -636,7 +636,7 @@ char kdb_task_state_char (const struct task_struct *p) (p->exit_state & EXIT_ZOMBIE) ? 'Z' : (p->exit_state & EXIT_DEAD) ? 'E' : (p->state & TASK_INTERRUPTIBLE) ? 'S' : '?'; - if (p->pid == 0) { + if (is_idle_task(p)) { /* Idle task. Is it really idle, apart from the kdb * interrupt? */ if (!kdb_task_has_cpu(p) || kgdb_info[cpu].irq_depth == 1) { diff --git a/kernel/events/core.c b/kernel/events/core.c index 24e3a4b..a8f4ac0 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4,7 +4,7 @@ * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com> - * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> + * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> * * For licensing details see kernel-base/COPYING */ @@ -5173,7 +5173,7 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) regs = get_irq_regs(); if (regs && !perf_exclude_event(event, regs)) { - if (!(event->attr.exclude_idle && current->pid == 0)) + if (!(event->attr.exclude_idle && is_idle_task(current))) if (perf_event_overflow(event, &data, regs)) ret = HRTIMER_NORESTART; } @@ -6941,10 +6941,13 @@ static int __perf_cgroup_move(void *info) return 0; } -static void -perf_cgroup_attach_task(struct cgroup *cgrp, struct task_struct *task) +static void perf_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, + struct cgroup_taskset *tset) { - task_function_call(task, __perf_cgroup_move, task); + struct task_struct *task; + + cgroup_taskset_for_each(task, cgrp, tset) + task_function_call(task, __perf_cgroup_move, task); } static void perf_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp, @@ -6958,7 +6961,7 @@ static void perf_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp, if (!(task->flags & PF_EXITING)) return; - perf_cgroup_attach_task(cgrp, task); + task_function_call(task, __perf_cgroup_move, task); } struct cgroup_subsys perf_subsys = { @@ -6967,6 +6970,6 @@ struct cgroup_subsys perf_subsys = { .create = perf_cgroup_create, .destroy = perf_cgroup_destroy, .exit = perf_cgroup_exit, - .attach_task = perf_cgroup_attach_task, + .attach = perf_cgroup_attach, }; #endif /* CONFIG_CGROUP_PERF */ diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index 7f3011c..6ddaba4 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -4,7 +4,7 @@ * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com> - * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> + * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> * * For licensing details see kernel-base/COPYING */ diff --git a/kernel/exit.c b/kernel/exit.c index e6e01b9..c447382 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -51,6 +51,7 @@ #include <trace/events/sched.h> #include <linux/hw_breakpoint.h> #include <linux/oom.h> +#include <linux/writeback.h> #include <asm/uaccess.h> #include <asm/unistd.h> @@ -121,9 +122,9 @@ static void __exit_signal(struct task_struct *tsk) * We won't ever get here for the group leader, since it * will have been the last reference on the signal_struct. */ - sig->utime = cputime_add(sig->utime, tsk->utime); - sig->stime = cputime_add(sig->stime, tsk->stime); - sig->gtime = cputime_add(sig->gtime, tsk->gtime); + sig->utime += tsk->utime; + sig->stime += tsk->stime; + sig->gtime += tsk->gtime; sig->min_flt += tsk->min_flt; sig->maj_flt += tsk->maj_flt; sig->nvcsw += tsk->nvcsw; @@ -679,8 +680,6 @@ static void exit_mm(struct task_struct * tsk) tsk->mm = NULL; up_read(&mm->mmap_sem); enter_lazy_tlb(mm, current); - /* We don't want this task to be frozen prematurely */ - clear_freeze_flag(tsk); task_unlock(tsk); mm_update_next_owner(mm); mmput(mm); @@ -888,7 +887,7 @@ static void check_stack_usage(void) static inline void check_stack_usage(void) {} #endif -NORET_TYPE void do_exit(long code) +void do_exit(long code) { struct task_struct *tsk = current; int group_dead; @@ -1037,9 +1036,12 @@ NORET_TYPE void do_exit(long code) validate_creds_for_do_exit(tsk); preempt_disable(); + if (tsk->nr_dirtied) + __this_cpu_add(dirty_throttle_leaks, tsk->nr_dirtied); exit_rcu(); /* causes final put_task_struct in finish_task_switch(). */ tsk->state = TASK_DEAD; + tsk->flags |= PF_NOFREEZE; /* tell freezer to ignore us */ schedule(); BUG(); /* Avoid "noreturn function does return". */ @@ -1049,7 +1051,7 @@ NORET_TYPE void do_exit(long code) EXPORT_SYMBOL_GPL(do_exit); -NORET_TYPE void complete_and_exit(struct completion *comp, long code) +void complete_and_exit(struct completion *comp, long code) { if (comp) complete(comp); @@ -1068,7 +1070,7 @@ SYSCALL_DEFINE1(exit, int, error_code) * Take down every thread in the group. This is called by fatal signals * as well as by sys_exit_group (below). */ -NORET_TYPE void +void do_group_exit(int exit_code) { struct signal_struct *sig = current->signal; @@ -1255,19 +1257,9 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p) spin_lock_irq(&p->real_parent->sighand->siglock); psig = p->real_parent->signal; sig = p->signal; - psig->cutime = - cputime_add(psig->cutime, - cputime_add(tgutime, - sig->cutime)); - psig->cstime = - cputime_add(psig->cstime, - cputime_add(tgstime, - sig->cstime)); - psig->cgtime = - cputime_add(psig->cgtime, - cputime_add(p->gtime, - cputime_add(sig->gtime, - sig->cgtime))); + psig->cutime += tgutime + sig->cutime; + psig->cstime += tgstime + sig->cstime; + psig->cgtime += p->gtime + sig->gtime + sig->cgtime; psig->cmin_flt += p->min_flt + sig->min_flt + sig->cmin_flt; psig->cmaj_flt += diff --git a/kernel/fork.c b/kernel/fork.c index da4a6a1..443f512 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -76,6 +76,9 @@ #include <trace/events/sched.h> +#define CREATE_TRACE_POINTS +#include <trace/events/task.h> + /* * Protected counters by write_lock_irq(&tasklist_lock) */ @@ -972,7 +975,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk) sched_autogroup_fork(sig); #ifdef CONFIG_CGROUPS - init_rwsem(&sig->threadgroup_fork_lock); + init_rwsem(&sig->group_rwsem); #endif sig->oom_adj = current->signal->oom_adj; @@ -992,7 +995,6 @@ static void copy_flags(unsigned long clone_flags, struct task_struct *p) new_flags |= PF_FORKNOEXEC; new_flags |= PF_STARTING; p->flags = new_flags; - clear_freeze_flag(p); } SYSCALL_DEFINE1(set_tid_address, int __user *, tidptr) @@ -1023,8 +1025,8 @@ void mm_init_owner(struct mm_struct *mm, struct task_struct *p) */ static void posix_cpu_timers_init(struct task_struct *tsk) { - tsk->cputime_expires.prof_exp = cputime_zero; - tsk->cputime_expires.virt_exp = cputime_zero; + tsk->cputime_expires.prof_exp = 0; + tsk->cputime_expires.virt_exp = 0; tsk->cputime_expires.sched_exp = 0; INIT_LIST_HEAD(&tsk->cpu_timers[0]); INIT_LIST_HEAD(&tsk->cpu_timers[1]); @@ -1132,14 +1134,10 @@ static struct task_struct *copy_process(unsigned long clone_flags, init_sigpending(&p->pending); - p->utime = cputime_zero; - p->stime = cputime_zero; - p->gtime = cputime_zero; - p->utimescaled = cputime_zero; - p->stimescaled = cputime_zero; + p->utime = p->stime = p->gtime = 0; + p->utimescaled = p->stimescaled = 0; #ifndef CONFIG_VIRT_CPU_ACCOUNTING - p->prev_utime = cputime_zero; - p->prev_stime = cputime_zero; + p->prev_utime = p->prev_stime = 0; #endif #if defined(SPLIT_RSS_COUNTING) memset(&p->rss_stat, 0, sizeof(p->rss_stat)); @@ -1158,7 +1156,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->io_context = NULL; p->audit_context = NULL; if (clone_flags & CLONE_THREAD) - threadgroup_fork_read_lock(current); + threadgroup_change_begin(current); cgroup_fork(p); #ifdef CONFIG_NUMA p->mempolicy = mpol_dup(p->mempolicy); @@ -1296,6 +1294,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->nr_dirtied = 0; p->nr_dirtied_pause = 128 >> (PAGE_SHIFT - 10); + p->dirty_paused_when = 0; /* * Ok, make it visible to the rest of the system. @@ -1373,8 +1372,11 @@ static struct task_struct *copy_process(unsigned long clone_flags, proc_fork_connector(p); cgroup_post_fork(p); if (clone_flags & CLONE_THREAD) - threadgroup_fork_read_unlock(current); + threadgroup_change_end(current); perf_event_fork(p); + + trace_task_newtask(p, clone_flags); + return p; bad_fork_free_pid: @@ -1408,7 +1410,7 @@ bad_fork_cleanup_policy: bad_fork_cleanup_cgroup: #endif if (clone_flags & CLONE_THREAD) - threadgroup_fork_read_unlock(current); + threadgroup_change_end(current); cgroup_exit(p, cgroup_callbacks_done); delayacct_tsk_free(p); module_put(task_thread_info(p)->exec_domain->module); diff --git a/kernel/freezer.c b/kernel/freezer.c index 7be56c5..9815b8d 100644 --- a/kernel/freezer.c +++ b/kernel/freezer.c @@ -9,101 +9,114 @@ #include <linux/export.h> #include <linux/syscalls.h> #include <linux/freezer.h> +#include <linux/kthread.h> -/* - * freezing is complete, mark current process as frozen +/* total number of freezing conditions in effect */ +atomic_t system_freezing_cnt = ATOMIC_INIT(0); +EXPORT_SYMBOL(system_freezing_cnt); + +/* indicate whether PM freezing is in effect, protected by pm_mutex */ +bool pm_freezing; +bool pm_nosig_freezing; + +/* protects freezing and frozen transitions */ +static DEFINE_SPINLOCK(freezer_lock); + +/** + * freezing_slow_path - slow path for testing whether a task needs to be frozen + * @p: task to be tested + * + * This function is called by freezing() if system_freezing_cnt isn't zero + * and tests whether @p needs to enter and stay in frozen state. Can be + * called under any context. The freezers are responsible for ensuring the + * target tasks see the updated state. */ -static inline void frozen_process(void) +bool freezing_slow_path(struct task_struct *p) { - if (!unlikely(current->flags & PF_NOFREEZE)) { - current->flags |= PF_FROZEN; - smp_wmb(); - } - clear_freeze_flag(current); + if (p->flags & PF_NOFREEZE) + return false; + + if (pm_nosig_freezing || cgroup_freezing(p)) + return true; + + if (pm_freezing && !(p->flags & PF_KTHREAD)) + return true; + + return false; } +EXPORT_SYMBOL(freezing_slow_path); /* Refrigerator is place where frozen processes are stored :-). */ -void refrigerator(void) +bool __refrigerator(bool check_kthr_stop) { /* Hmm, should we be allowed to suspend when there are realtime processes around? */ - long save; + bool was_frozen = false; + long save = current->state; - task_lock(current); - if (freezing(current)) { - frozen_process(); - task_unlock(current); - } else { - task_unlock(current); - return; - } - save = current->state; pr_debug("%s entered refrigerator\n", current->comm); - spin_lock_irq(¤t->sighand->siglock); - recalc_sigpending(); /* We sent fake signal, clean it up */ - spin_unlock_irq(¤t->sighand->siglock); - - /* prevent accounting of that task to load */ - current->flags |= PF_FREEZING; - for (;;) { set_current_state(TASK_UNINTERRUPTIBLE); - if (!frozen(current)) + + spin_lock_irq(&freezer_lock); + current->flags |= PF_FROZEN; + if (!freezing(current) || + (check_kthr_stop && kthread_should_stop())) + current->flags &= ~PF_FROZEN; + spin_unlock_irq(&freezer_lock); + + if (!(current->flags & PF_FROZEN)) break; + was_frozen = true; schedule(); } - /* Remove the accounting blocker */ - current->flags &= ~PF_FREEZING; - pr_debug("%s left refrigerator\n", current->comm); - __set_current_state(save); + + /* + * Restore saved task state before returning. The mb'd version + * needs to be used; otherwise, it might silently break + * synchronization which depends on ordered task state change. + */ + set_current_state(save); + + return was_frozen; } -EXPORT_SYMBOL(refrigerator); +EXPORT_SYMBOL(__refrigerator); static void fake_signal_wake_up(struct task_struct *p) { unsigned long flags; - spin_lock_irqsave(&p->sighand->siglock, flags); - signal_wake_up(p, 0); - spin_unlock_irqrestore(&p->sighand->siglock, flags); + if (lock_task_sighand(p, &flags)) { + signal_wake_up(p, 0); + unlock_task_sighand(p, &flags); + } } /** - * freeze_task - send a freeze request to given task - * @p: task to send the request to - * @sig_only: if set, the request will only be sent if the task has the - * PF_FREEZER_NOSIG flag unset - * Return value: 'false', if @sig_only is set and the task has - * PF_FREEZER_NOSIG set or the task is frozen, 'true', otherwise + * freeze_task - send a freeze request to given task + * @p: task to send the request to + * + * If @p is freezing, the freeze request is sent by setting %TIF_FREEZE + * flag and either sending a fake signal to it or waking it up, depending + * on whether it has %PF_FREEZER_NOSIG set. * - * The freeze request is sent by setting the tasks's TIF_FREEZE flag and - * either sending a fake signal to it or waking it up, depending on whether - * or not it has PF_FREEZER_NOSIG set. If @sig_only is set and the task - * has PF_FREEZER_NOSIG set (ie. it is a typical kernel thread), its - * TIF_FREEZE flag will not be set. + * RETURNS: + * %false, if @p is not freezing or already frozen; %true, otherwise */ -bool freeze_task(struct task_struct *p, bool sig_only) +bool freeze_task(struct task_struct *p) { - /* - * We first check if the task is freezing and next if it has already - * been frozen to avoid the race with frozen_process() which first marks - * the task as frozen and next clears its TIF_FREEZE. - */ - if (!freezing(p)) { - smp_rmb(); - if (frozen(p)) - return false; - - if (!sig_only || should_send_signal(p)) - set_freeze_flag(p); - else - return false; + unsigned long flags; + + spin_lock_irqsave(&freezer_lock, flags); + if (!freezing(p) || frozen(p)) { + spin_unlock_irqrestore(&freezer_lock, flags); + return false; } - if (should_send_signal(p)) { + if (!(p->flags & PF_KTHREAD)) { fake_signal_wake_up(p); /* * fake_signal_wake_up() goes through p's scheduler @@ -111,56 +124,48 @@ bool freeze_task(struct task_struct *p, bool sig_only) * TASK_RUNNING transition can't race with task state * testing in try_to_freeze_tasks(). */ - } else if (sig_only) { - return false; } else { wake_up_state(p, TASK_INTERRUPTIBLE); } + spin_unlock_irqrestore(&freezer_lock, flags); return true; } -void cancel_freezing(struct task_struct *p) +void __thaw_task(struct task_struct *p) { unsigned long flags; - if (freezing(p)) { - pr_debug(" clean up: %s\n", p->comm); - clear_freeze_flag(p); - spin_lock_irqsave(&p->sighand->siglock, flags); - recalc_sigpending_and_wake(p); - spin_unlock_irqrestore(&p->sighand->siglock, flags); - } -} - -static int __thaw_process(struct task_struct *p) -{ - if (frozen(p)) { - p->flags &= ~PF_FROZEN; - return 1; - } - clear_freeze_flag(p); - return 0; + /* + * Clear freezing and kick @p if FROZEN. Clearing is guaranteed to + * be visible to @p as waking up implies wmb. Waking up inside + * freezer_lock also prevents wakeups from leaking outside + * refrigerator. + */ + spin_lock_irqsave(&freezer_lock, flags); + if (frozen(p)) + wake_up_process(p); + spin_unlock_irqrestore(&freezer_lock, flags); } -/* - * Wake up a frozen process +/** + * set_freezable - make %current freezable * - * task_lock() is needed to prevent the race with refrigerator() which may - * occur if the freezing of tasks fails. Namely, without the lock, if the - * freezing of tasks failed, thaw_tasks() might have run before a task in - * refrigerator() could call frozen_process(), in which case the task would be - * frozen and no one would thaw it. + * Mark %current freezable and enter refrigerator if necessary. */ -int thaw_process(struct task_struct *p) +bool set_freezable(void) { - task_lock(p); - if (__thaw_process(p) == 1) { - task_unlock(p); - wake_up_process(p); - return 1; - } - task_unlock(p); - return 0; + might_sleep(); + + /* + * Modify flags while holding freezer_lock. This ensures the + * freezer notices that we aren't frozen yet or the freezing + * condition is visible to try_to_freeze() below. + */ + spin_lock_irq(&freezer_lock); + current->flags &= ~PF_NOFREEZE; + spin_unlock_irq(&freezer_lock); + + return try_to_freeze(); } -EXPORT_SYMBOL(thaw_process); +EXPORT_SYMBOL(set_freezable); diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index a73dd6c..b795231 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -15,7 +15,7 @@ #define istate core_internal_state__do_not_mess_with_it -extern int noirqdebug; +extern bool noirqdebug; /* * Bits used by threaded handlers: diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 200ce83..1f9e265 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -135,6 +135,9 @@ int irq_domain_simple_dt_translate(struct irq_domain *d, return -EINVAL; if (intsize < 1) return -EINVAL; + if (d->nr_irq && ((intspec[0] < d->hwirq_base) || + (intspec[0] >= d->hwirq_base + d->nr_irq))) + return -EINVAL; *out_hwirq = intspec[0]; *out_type = IRQ_TYPE_NONE; @@ -143,11 +146,6 @@ int irq_domain_simple_dt_translate(struct irq_domain *d, return 0; } -struct irq_domain_ops irq_domain_simple_ops = { - .dt_translate = irq_domain_simple_dt_translate, -}; -EXPORT_SYMBOL_GPL(irq_domain_simple_ops); - /** * irq_domain_create_simple() - Set up a 'simple' translation range */ @@ -182,3 +180,10 @@ void irq_domain_generate_simple(const struct of_device_id *match, } EXPORT_SYMBOL_GPL(irq_domain_generate_simple); #endif /* CONFIG_OF_IRQ */ + +struct irq_domain_ops irq_domain_simple_ops = { +#ifdef CONFIG_OF_IRQ + .dt_translate = irq_domain_simple_dt_translate, +#endif /* CONFIG_OF_IRQ */ +}; +EXPORT_SYMBOL_GPL(irq_domain_simple_ops); diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 1da999f..a9a9dbe 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -1292,7 +1292,7 @@ EXPORT_SYMBOL(free_irq); * and to set up the interrupt handler in the right order. * * If you want to set up a threaded irq handler for your device - * then you need to supply @handler and @thread_fn. @handler ist + * then you need to supply @handler and @thread_fn. @handler is * still called in hard interrupt context and has to check * whether the interrupt originates from the device. If yes it * needs to disable the interrupt on the device and return diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c index dc813a9..611cd60 100644 --- a/kernel/irq/spurious.c +++ b/kernel/irq/spurious.c @@ -325,7 +325,7 @@ void note_interrupt(unsigned int irq, struct irq_desc *desc, desc->irqs_unhandled = 0; } -int noirqdebug __read_mostly; +bool noirqdebug __read_mostly; int noirqdebug_setup(char *str) { diff --git a/kernel/itimer.c b/kernel/itimer.c index d802883..22000c3 100644 --- a/kernel/itimer.c +++ b/kernel/itimer.c @@ -52,22 +52,22 @@ static void get_cpu_itimer(struct task_struct *tsk, unsigned int clock_id, cval = it->expires; cinterval = it->incr; - if (!cputime_eq(cval, cputime_zero)) { + if (cval) { struct task_cputime cputime; cputime_t t; thread_group_cputimer(tsk, &cputime); if (clock_id == CPUCLOCK_PROF) - t = cputime_add(cputime.utime, cputime.stime); + t = cputime.utime + cputime.stime; else /* CPUCLOCK_VIRT */ t = cputime.utime; - if (cputime_le(cval, t)) + if (cval < t) /* about to fire */ cval = cputime_one_jiffy; else - cval = cputime_sub(cval, t); + cval = cval - t; } spin_unlock_irq(&tsk->sighand->siglock); @@ -161,10 +161,9 @@ static void set_cpu_itimer(struct task_struct *tsk, unsigned int clock_id, 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); + if (cval || nval) { + if (nval > 0) + nval += cputime_one_jiffy; set_process_cpu_timer(tsk, clock_id, &nval, &cval); } it->expires = nval; diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 30c3c77..01d3b70 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -71,6 +71,7 @@ void jump_label_inc(struct jump_label_key *key) atomic_inc(&key->enabled); jump_label_unlock(); } +EXPORT_SYMBOL_GPL(jump_label_inc); static void __jump_label_dec(struct jump_label_key *key, unsigned long rate_limit, struct delayed_work *work) @@ -86,6 +87,7 @@ static void __jump_label_dec(struct jump_label_key *key, jump_label_unlock(); } +EXPORT_SYMBOL_GPL(jump_label_dec); static void jump_label_update_timeout(struct work_struct *work) { diff --git a/kernel/kexec.c b/kernel/kexec.c index dc7bc08..7b08867 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -32,7 +32,6 @@ #include <linux/console.h> #include <linux/vmalloc.h> #include <linux/swap.h> -#include <linux/kmsg_dump.h> #include <linux/syscore_ops.h> #include <asm/page.h> @@ -1094,8 +1093,6 @@ void crash_kexec(struct pt_regs *regs) if (kexec_crash_image) { struct pt_regs fixed_regs; - kmsg_dump(KMSG_DUMP_KEXEC); - crash_setup_regs(&fixed_regs, regs); crash_save_vmcoreinfo(); machine_crash_shutdown(&fixed_regs); @@ -1132,6 +1129,8 @@ int crash_shrink_memory(unsigned long new_size) { int ret = 0; unsigned long start, end; + unsigned long old_size; + struct resource *ram_res; mutex_lock(&kexec_mutex); @@ -1141,11 +1140,15 @@ int crash_shrink_memory(unsigned long new_size) } start = crashk_res.start; end = crashk_res.end; + old_size = (end == 0) ? 0 : end - start + 1; + if (new_size >= old_size) { + ret = (new_size == old_size) ? 0 : -EINVAL; + goto unlock; + } - if (new_size >= end - start + 1) { - ret = -EINVAL; - if (new_size == end - start + 1) - ret = 0; + ram_res = kzalloc(sizeof(*ram_res), GFP_KERNEL); + if (!ram_res) { + ret = -ENOMEM; goto unlock; } @@ -1157,7 +1160,15 @@ int crash_shrink_memory(unsigned long new_size) if ((start == end) && (crashk_res.parent != NULL)) release_resource(&crashk_res); + + ram_res->start = end; + ram_res->end = crashk_res.end; + ram_res->flags = IORESOURCE_BUSY | IORESOURCE_MEM; + ram_res->name = "System RAM"; + crashk_res.end = end - 1; + + insert_resource(&iomem_resource, ram_res); crash_unmap_reserved_pages(); unlock: @@ -1523,7 +1534,7 @@ int kernel_kexec(void) #ifdef CONFIG_KEXEC_JUMP if (kexec_image->preserve_context) { - mutex_lock(&pm_mutex); + lock_system_sleep(); pm_prepare_console(); error = freeze_processes(); if (error) { @@ -1576,7 +1587,7 @@ int kernel_kexec(void) thaw_processes(); Restore_console: pm_restore_console(); - mutex_unlock(&pm_mutex); + unlock_system_sleep(); } #endif diff --git a/kernel/kmod.c b/kernel/kmod.c index a4bea97..a0a8854 100644 --- a/kernel/kmod.c +++ b/kernel/kmod.c @@ -36,6 +36,7 @@ #include <linux/resource.h> #include <linux/notifier.h> #include <linux/suspend.h> +#include <linux/rwsem.h> #include <asm/uaccess.h> #include <trace/events/module.h> @@ -50,6 +51,7 @@ static struct workqueue_struct *khelper_wq; static kernel_cap_t usermodehelper_bset = CAP_FULL_SET; static kernel_cap_t usermodehelper_inheritable = CAP_FULL_SET; static DEFINE_SPINLOCK(umh_sysctl_lock); +static DECLARE_RWSEM(umhelper_sem); #ifdef CONFIG_MODULES @@ -275,6 +277,7 @@ static void __call_usermodehelper(struct work_struct *work) * If set, call_usermodehelper_exec() will exit immediately returning -EBUSY * (used for preventing user land processes from being created after the user * land has been frozen during a system-wide hibernation or suspend operation). + * Should always be manipulated under umhelper_sem acquired for write. */ static int usermodehelper_disabled = 1; @@ -282,17 +285,29 @@ static int usermodehelper_disabled = 1; static atomic_t running_helpers = ATOMIC_INIT(0); /* - * Wait queue head used by usermodehelper_pm_callback() to wait for all running + * Wait queue head used by usermodehelper_disable() to wait for all running * helpers to finish. */ static DECLARE_WAIT_QUEUE_HEAD(running_helpers_waitq); /* * Time to wait for running_helpers to become zero before the setting of - * usermodehelper_disabled in usermodehelper_pm_callback() fails + * usermodehelper_disabled in usermodehelper_disable() fails */ #define RUNNING_HELPERS_TIMEOUT (5 * HZ) +void read_lock_usermodehelper(void) +{ + down_read(&umhelper_sem); +} +EXPORT_SYMBOL_GPL(read_lock_usermodehelper); + +void read_unlock_usermodehelper(void) +{ + up_read(&umhelper_sem); +} +EXPORT_SYMBOL_GPL(read_unlock_usermodehelper); + /** * usermodehelper_disable - prevent new helpers from being started */ @@ -300,8 +315,10 @@ int usermodehelper_disable(void) { long retval; + down_write(&umhelper_sem); usermodehelper_disabled = 1; - smp_mb(); + up_write(&umhelper_sem); + /* * From now on call_usermodehelper_exec() won't start any new * helpers, so it is sufficient if running_helpers turns out to @@ -314,7 +331,9 @@ int usermodehelper_disable(void) if (retval) return 0; + down_write(&umhelper_sem); usermodehelper_disabled = 0; + up_write(&umhelper_sem); return -EAGAIN; } @@ -323,7 +342,9 @@ int usermodehelper_disable(void) */ void usermodehelper_enable(void) { + down_write(&umhelper_sem); usermodehelper_disabled = 0; + up_write(&umhelper_sem); } /** diff --git a/kernel/kprobes.c b/kernel/kprobes.c index e5d8464..95dd721 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -2198,7 +2198,7 @@ static ssize_t write_enabled_file_bool(struct file *file, const char __user *user_buf, size_t count, loff_t *ppos) { char buf[32]; - int buf_size; + size_t buf_size; buf_size = min(count, (sizeof(buf)-1)); if (copy_from_user(buf, user_buf, buf_size)) diff --git a/kernel/kthread.c b/kernel/kthread.c index b6d216a..3d3de633 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -59,6 +59,31 @@ int kthread_should_stop(void) EXPORT_SYMBOL(kthread_should_stop); /** + * kthread_freezable_should_stop - should this freezable kthread return now? + * @was_frozen: optional out parameter, indicates whether %current was frozen + * + * kthread_should_stop() for freezable kthreads, which will enter + * refrigerator if necessary. This function is safe from kthread_stop() / + * freezer deadlock and freezable kthreads should use this function instead + * of calling try_to_freeze() directly. + */ +bool kthread_freezable_should_stop(bool *was_frozen) +{ + bool frozen = false; + + might_sleep(); + + if (unlikely(freezing(current))) + frozen = __refrigerator(true); + + if (was_frozen) + *was_frozen = frozen; + + return kthread_should_stop(); +} +EXPORT_SYMBOL_GPL(kthread_freezable_should_stop); + +/** * kthread_data - return data value specified on kthread creation * @task: kthread task in question * @@ -257,7 +282,7 @@ int kthreadd(void *unused) set_cpus_allowed_ptr(tsk, cpu_all_mask); set_mems_allowed(node_states[N_HIGH_MEMORY]); - current->flags |= PF_NOFREEZE | PF_FREEZER_NOSIG; + current->flags |= PF_NOFREEZE; for (;;) { set_current_state(TASK_INTERRUPTIBLE); diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 24f176c..8889f7d 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -431,6 +431,7 @@ unsigned int max_lockdep_depth; * about it later on, in lockdep_info(). */ static int lockdep_init_error; +static const char *lock_init_error; static unsigned long lockdep_init_trace_data[20]; static struct stack_trace lockdep_init_trace = { .max_entries = ARRAY_SIZE(lockdep_init_trace_data), @@ -564,11 +565,12 @@ static void lockdep_print_held_locks(struct task_struct *curr) } } -static void print_kernel_version(void) +static void print_kernel_ident(void) { - printk("%s %.*s\n", init_utsname()->release, + printk("%s %.*s %s\n", init_utsname()->release, (int)strcspn(init_utsname()->version, " "), - init_utsname()->version); + init_utsname()->version, + print_tainted()); } static int very_verbose(struct lock_class *class) @@ -652,6 +654,7 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass) if (unlikely(!lockdep_initialized)) { lockdep_init(); lockdep_init_error = 1; + lock_init_error = lock->name; save_stack_trace(&lockdep_init_trace); } #endif @@ -719,7 +722,7 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force) class = look_up_lock_class(lock, subclass); if (likely(class)) - return class; + goto out_set_class_cache; /* * Debug-check: all keys must be persistent! @@ -804,6 +807,7 @@ out_unlock_set: graph_unlock(); raw_local_irq_restore(flags); +out_set_class_cache: if (!subclass || force) lock->class_cache[0] = class; else if (subclass < NR_LOCKDEP_CACHING_CLASSES) @@ -1145,7 +1149,7 @@ print_circular_bug_header(struct lock_list *entry, unsigned int depth, printk("\n"); printk("======================================================\n"); printk("[ INFO: possible circular locking dependency detected ]\n"); - print_kernel_version(); + print_kernel_ident(); printk("-------------------------------------------------------\n"); printk("%s/%d is trying to acquire lock:\n", curr->comm, task_pid_nr(curr)); @@ -1484,7 +1488,7 @@ print_bad_irq_dependency(struct task_struct *curr, printk("======================================================\n"); printk("[ INFO: %s-safe -> %s-unsafe lock order detected ]\n", irqclass, irqclass); - print_kernel_version(); + print_kernel_ident(); printk("------------------------------------------------------\n"); printk("%s/%d [HC%u[%lu]:SC%u[%lu]:HE%u:SE%u] is trying to acquire:\n", curr->comm, task_pid_nr(curr), @@ -1713,7 +1717,7 @@ print_deadlock_bug(struct task_struct *curr, struct held_lock *prev, printk("\n"); printk("=============================================\n"); printk("[ INFO: possible recursive locking detected ]\n"); - print_kernel_version(); + print_kernel_ident(); printk("---------------------------------------------\n"); printk("%s/%d is trying to acquire lock:\n", curr->comm, task_pid_nr(curr)); @@ -2220,7 +2224,7 @@ print_usage_bug(struct task_struct *curr, struct held_lock *this, printk("\n"); printk("=================================\n"); printk("[ INFO: inconsistent lock state ]\n"); - print_kernel_version(); + print_kernel_ident(); printk("---------------------------------\n"); printk("inconsistent {%s} -> {%s} usage.\n", @@ -2285,7 +2289,7 @@ print_irq_inversion_bug(struct task_struct *curr, printk("\n"); printk("=========================================================\n"); printk("[ INFO: possible irq lock inversion dependency detected ]\n"); - print_kernel_version(); + print_kernel_ident(); printk("---------------------------------------------------------\n"); printk("%s/%d just changed the state of lock:\n", curr->comm, task_pid_nr(curr)); @@ -3171,6 +3175,7 @@ print_unlock_inbalance_bug(struct task_struct *curr, struct lockdep_map *lock, printk("\n"); printk("=====================================\n"); printk("[ BUG: bad unlock balance detected! ]\n"); + print_kernel_ident(); printk("-------------------------------------\n"); printk("%s/%d is trying to release lock (", curr->comm, task_pid_nr(curr)); @@ -3615,6 +3620,7 @@ print_lock_contention_bug(struct task_struct *curr, struct lockdep_map *lock, printk("\n"); printk("=================================\n"); printk("[ BUG: bad contention detected! ]\n"); + print_kernel_ident(); printk("---------------------------------\n"); printk("%s/%d is trying to contend lock (", curr->comm, task_pid_nr(curr)); @@ -3970,7 +3976,8 @@ void __init lockdep_info(void) #ifdef CONFIG_DEBUG_LOCKDEP if (lockdep_init_error) { - printk("WARNING: lockdep init error! Arch code didn't call lockdep_init() early enough?\n"); + printk("WARNING: lockdep init error! lock-%s was acquired" + "before lockdep_init\n", lock_init_error); printk("Call stack leading to lockdep invocation was:\n"); print_stack_trace(&lockdep_init_trace, 0); } @@ -3989,6 +3996,7 @@ print_freed_lock_bug(struct task_struct *curr, const void *mem_from, printk("\n"); printk("=========================\n"); printk("[ BUG: held lock freed! ]\n"); + print_kernel_ident(); printk("-------------------------\n"); printk("%s/%d is freeing memory %p-%p, with a lock still held there!\n", curr->comm, task_pid_nr(curr), mem_from, mem_to-1); @@ -4046,6 +4054,7 @@ static void print_held_locks_bug(struct task_struct *curr) printk("\n"); printk("=====================================\n"); printk("[ BUG: lock held at task exit time! ]\n"); + print_kernel_ident(); printk("-------------------------------------\n"); printk("%s/%d is exiting with locks still held!\n", curr->comm, task_pid_nr(curr)); @@ -4143,6 +4152,7 @@ void lockdep_sys_exit(void) printk("\n"); printk("================================================\n"); printk("[ BUG: lock held when returning to user space! ]\n"); + print_kernel_ident(); printk("------------------------------------------------\n"); printk("%s/%d is leaving the kernel with locks still held!\n", curr->comm, curr->pid); @@ -4162,10 +4172,33 @@ void lockdep_rcu_suspicious(const char *file, const int line, const char *s) printk("\n"); printk("===============================\n"); printk("[ INFO: suspicious RCU usage. ]\n"); + print_kernel_ident(); printk("-------------------------------\n"); printk("%s:%d %s!\n", file, line, s); printk("\nother info that might help us debug this:\n\n"); printk("\nrcu_scheduler_active = %d, debug_locks = %d\n", rcu_scheduler_active, debug_locks); + + /* + * If a CPU is in the RCU-free window in idle (ie: in the section + * between rcu_idle_enter() and rcu_idle_exit(), then RCU + * considers that CPU to be in an "extended quiescent state", + * which means that RCU will be completely ignoring that CPU. + * Therefore, rcu_read_lock() and friends have absolutely no + * effect on a CPU running in that state. In other words, even if + * such an RCU-idle CPU has called rcu_read_lock(), RCU might well + * delete data structures out from under it. RCU really has no + * choice here: we need to keep an RCU-free window in idle where + * the CPU may possibly enter into low power mode. This way we can + * notice an extended quiescent state to other CPUs that started a grace + * period. Otherwise we would delay any grace period as long as we run + * in the idle task. + * + * So complain bitterly if someone does call rcu_read_lock(), + * rcu_read_lock_bh() and so on from extended quiescent states. + */ + if (rcu_is_cpu_idle()) + printk("RCU used illegally from extended quiescent state!\n"); + lockdep_print_held_locks(curr); printk("\nstack backtrace:\n"); dump_stack(); diff --git a/kernel/module.c b/kernel/module.c index 178333c..acf6ed3 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -62,12 +62,6 @@ #define CREATE_TRACE_POINTS #include <trace/events/module.h> -#if 0 -#define DEBUGP printk -#else -#define DEBUGP(fmt , a...) -#endif - #ifndef ARCH_SHF_SMALL #define ARCH_SHF_SMALL 0 #endif @@ -138,7 +132,6 @@ struct load_info { unsigned long len; Elf_Shdr *sechdrs; char *secstrings, *strtab; - unsigned long *strmap; unsigned long symoffs, stroffs; struct _ddebug *debug; unsigned int num_debug; @@ -410,7 +403,7 @@ const struct kernel_symbol *find_symbol(const char *name, return fsa.sym; } - DEBUGP("Failed to find symbol %s\n", name); + pr_debug("Failed to find symbol %s\n", name); return NULL; } EXPORT_SYMBOL_GPL(find_symbol); @@ -600,11 +593,11 @@ static int already_uses(struct module *a, struct module *b) list_for_each_entry(use, &b->source_list, source_list) { if (use->source == a) { - DEBUGP("%s uses %s!\n", a->name, b->name); + pr_debug("%s uses %s!\n", a->name, b->name); return 1; } } - DEBUGP("%s does not use %s!\n", a->name, b->name); + pr_debug("%s does not use %s!\n", a->name, b->name); return 0; } @@ -619,7 +612,7 @@ static int add_module_usage(struct module *a, struct module *b) { struct module_use *use; - DEBUGP("Allocating new usage for %s.\n", a->name); + pr_debug("Allocating new usage for %s.\n", a->name); use = kmalloc(sizeof(*use), GFP_ATOMIC); if (!use) { printk(KERN_WARNING "%s: out of memory loading\n", a->name); @@ -663,7 +656,7 @@ static void module_unload_free(struct module *mod) mutex_lock(&module_mutex); list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) { struct module *i = use->target; - DEBUGP("%s unusing %s\n", mod->name, i->name); + pr_debug("%s unusing %s\n", mod->name, i->name); module_put(i); list_del(&use->source_list); list_del(&use->target_list); @@ -726,9 +719,9 @@ static int try_stop_module(struct module *mod, int flags, int *forced) } } -unsigned int module_refcount(struct module *mod) +unsigned long module_refcount(struct module *mod) { - unsigned int incs = 0, decs = 0; + unsigned long incs = 0, decs = 0; int cpu; for_each_possible_cpu(cpu) @@ -761,7 +754,7 @@ static void wait_for_zero_refcount(struct module *mod) /* Since we might sleep for some time, release the mutex first */ mutex_unlock(&module_mutex); for (;;) { - DEBUGP("Looking at refcount...\n"); + pr_debug("Looking at refcount...\n"); set_current_state(TASK_UNINTERRUPTIBLE); if (module_refcount(mod) == 0) break; @@ -804,7 +797,7 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user, if (mod->state != MODULE_STATE_LIVE) { /* FIXME: if (force), slam module count and wake up waiter --RR */ - DEBUGP("%s already dying\n", mod->name); + pr_debug("%s already dying\n", mod->name); ret = -EBUSY; goto out; } @@ -849,12 +842,32 @@ out: return ret; } +static size_t module_flags_taint(struct module *mod, char *buf) +{ + size_t l = 0; + + if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE)) + buf[l++] = 'P'; + if (mod->taints & (1 << TAINT_OOT_MODULE)) + buf[l++] = 'O'; + if (mod->taints & (1 << TAINT_FORCED_MODULE)) + buf[l++] = 'F'; + if (mod->taints & (1 << TAINT_CRAP)) + buf[l++] = 'C'; + /* + * TAINT_FORCED_RMMOD: could be added. + * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't + * apply to modules. + */ + return l; +} + static inline void print_unload_info(struct seq_file *m, struct module *mod) { struct module_use *use; int printed_something = 0; - seq_printf(m, " %u ", module_refcount(mod)); + seq_printf(m, " %lu ", module_refcount(mod)); /* Always include a trailing , so userspace can differentiate between this and the old multi-field proc format. */ @@ -904,13 +917,11 @@ EXPORT_SYMBOL_GPL(symbol_put_addr); static ssize_t show_refcnt(struct module_attribute *mattr, struct module_kobject *mk, char *buffer) { - return sprintf(buffer, "%u\n", module_refcount(mk->mod)); + return sprintf(buffer, "%lu\n", module_refcount(mk->mod)); } -static struct module_attribute refcnt = { - .attr = { .name = "refcnt", .mode = 0444 }, - .show = show_refcnt, -}; +static struct module_attribute modinfo_refcnt = + __ATTR(refcnt, 0444, show_refcnt, NULL); void module_put(struct module *module) { @@ -970,10 +981,8 @@ static ssize_t show_initstate(struct module_attribute *mattr, return sprintf(buffer, "%s\n", state); } -static struct module_attribute initstate = { - .attr = { .name = "initstate", .mode = 0444 }, - .show = show_initstate, -}; +static struct module_attribute modinfo_initstate = + __ATTR(initstate, 0444, show_initstate, NULL); static ssize_t store_uevent(struct module_attribute *mattr, struct module_kobject *mk, @@ -986,18 +995,50 @@ static ssize_t store_uevent(struct module_attribute *mattr, return count; } -struct module_attribute module_uevent = { - .attr = { .name = "uevent", .mode = 0200 }, - .store = store_uevent, -}; +struct module_attribute module_uevent = + __ATTR(uevent, 0200, NULL, store_uevent); + +static ssize_t show_coresize(struct module_attribute *mattr, + struct module_kobject *mk, char *buffer) +{ + return sprintf(buffer, "%u\n", mk->mod->core_size); +} + +static struct module_attribute modinfo_coresize = + __ATTR(coresize, 0444, show_coresize, NULL); + +static ssize_t show_initsize(struct module_attribute *mattr, + struct module_kobject *mk, char *buffer) +{ + return sprintf(buffer, "%u\n", mk->mod->init_size); +} + +static struct module_attribute modinfo_initsize = + __ATTR(initsize, 0444, show_initsize, NULL); + +static ssize_t show_taint(struct module_attribute *mattr, + struct module_kobject *mk, char *buffer) +{ + size_t l; + + l = module_flags_taint(mk->mod, buffer); + buffer[l++] = '\n'; + return l; +} + +static struct module_attribute modinfo_taint = + __ATTR(taint, 0444, show_taint, NULL); static struct module_attribute *modinfo_attrs[] = { + &module_uevent, &modinfo_version, &modinfo_srcversion, - &initstate, - &module_uevent, + &modinfo_initstate, + &modinfo_coresize, + &modinfo_initsize, + &modinfo_taint, #ifdef CONFIG_MODULE_UNLOAD - &refcnt, + &modinfo_refcnt, #endif NULL, }; @@ -1057,7 +1098,7 @@ static int check_version(Elf_Shdr *sechdrs, if (versions[i].crc == maybe_relocated(*crc, crc_owner)) return 1; - DEBUGP("Found checksum %lX vs module %lX\n", + pr_debug("Found checksum %lX vs module %lX\n", maybe_relocated(*crc, crc_owner), versions[i].crc); goto bad_version; } @@ -1834,7 +1875,7 @@ static int simplify_symbols(struct module *mod, const struct load_info *info) case SHN_COMMON: /* We compiled with -fno-common. These are not supposed to happen. */ - DEBUGP("Common symbol: %s\n", name); + pr_debug("Common symbol: %s\n", name); printk("%s: please compile with -fno-common\n", mod->name); ret = -ENOEXEC; @@ -1842,7 +1883,7 @@ static int simplify_symbols(struct module *mod, const struct load_info *info) case SHN_ABS: /* Don't need to do anything */ - DEBUGP("Absolute symbol: 0x%08lx\n", + pr_debug("Absolute symbol: 0x%08lx\n", (long)sym[i].st_value); break; @@ -1966,7 +2007,7 @@ static void layout_sections(struct module *mod, struct load_info *info) for (i = 0; i < info->hdr->e_shnum; i++) info->sechdrs[i].sh_entsize = ~0UL; - DEBUGP("Core section allocation order:\n"); + pr_debug("Core section allocation order:\n"); for (m = 0; m < ARRAY_SIZE(masks); ++m) { for (i = 0; i < info->hdr->e_shnum; ++i) { Elf_Shdr *s = &info->sechdrs[i]; @@ -1978,7 +2019,7 @@ static void layout_sections(struct module *mod, struct load_info *info) || strstarts(sname, ".init")) continue; s->sh_entsize = get_offset(mod, &mod->core_size, s, i); - DEBUGP("\t%s\n", name); + pr_debug("\t%s\n", sname); } switch (m) { case 0: /* executable */ @@ -1995,7 +2036,7 @@ static void layout_sections(struct module *mod, struct load_info *info) } } - DEBUGP("Init section allocation order:\n"); + pr_debug("Init section allocation order:\n"); for (m = 0; m < ARRAY_SIZE(masks); ++m) { for (i = 0; i < info->hdr->e_shnum; ++i) { Elf_Shdr *s = &info->sechdrs[i]; @@ -2008,7 +2049,7 @@ static void layout_sections(struct module *mod, struct load_info *info) continue; s->sh_entsize = (get_offset(mod, &mod->init_size, s, i) | INIT_OFFSET_MASK); - DEBUGP("\t%s\n", sname); + pr_debug("\t%s\n", sname); } switch (m) { case 0: /* executable */ @@ -2178,45 +2219,46 @@ static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs, return true; } +/* + * We only allocate and copy the strings needed by the parts of symtab + * we keep. This is simple, but has the effect of making multiple + * copies of duplicates. We could be more sophisticated, see + * linux-kernel thread starting with + * <73defb5e4bca04a6431392cc341112b1@localhost>. + */ static void layout_symtab(struct module *mod, struct load_info *info) { Elf_Shdr *symsect = info->sechdrs + info->index.sym; Elf_Shdr *strsect = info->sechdrs + info->index.str; const Elf_Sym *src; - unsigned int i, nsrc, ndst; + unsigned int i, nsrc, ndst, strtab_size; /* Put symbol section at end of init part of module. */ symsect->sh_flags |= SHF_ALLOC; symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect, info->index.sym) | INIT_OFFSET_MASK; - DEBUGP("\t%s\n", info->secstrings + symsect->sh_name); + pr_debug("\t%s\n", info->secstrings + symsect->sh_name); src = (void *)info->hdr + symsect->sh_offset; nsrc = symsect->sh_size / sizeof(*src); - for (ndst = i = 1; i < nsrc; ++i, ++src) - if (is_core_symbol(src, info->sechdrs, info->hdr->e_shnum)) { - unsigned int j = src->st_name; - while (!__test_and_set_bit(j, info->strmap) - && info->strtab[j]) - ++j; - ++ndst; + /* Compute total space required for the core symbols' strtab. */ + for (ndst = i = strtab_size = 1; i < nsrc; ++i, ++src) + if (is_core_symbol(src, info->sechdrs, info->hdr->e_shnum)) { + strtab_size += strlen(&info->strtab[src->st_name]) + 1; + ndst++; } /* Append room for core symbols at end of core part. */ info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1); - mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym); + info->stroffs = mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym); + mod->core_size += strtab_size; /* Put string table section at end of init part of module. */ strsect->sh_flags |= SHF_ALLOC; strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect, info->index.str) | INIT_OFFSET_MASK; - DEBUGP("\t%s\n", info->secstrings + strsect->sh_name); - - /* Append room for core symbols' strings at end of core part. */ - info->stroffs = mod->core_size; - __set_bit(0, info->strmap); - mod->core_size += bitmap_weight(info->strmap, strsect->sh_size); + pr_debug("\t%s\n", info->secstrings + strsect->sh_name); } static void add_kallsyms(struct module *mod, const struct load_info *info) @@ -2237,22 +2279,19 @@ static void add_kallsyms(struct module *mod, const struct load_info *info) mod->symtab[i].st_info = elf_type(&mod->symtab[i], info); mod->core_symtab = dst = mod->module_core + info->symoffs; + mod->core_strtab = s = mod->module_core + info->stroffs; src = mod->symtab; *dst = *src; + *s++ = 0; for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) { if (!is_core_symbol(src, info->sechdrs, info->hdr->e_shnum)) continue; + dst[ndst] = *src; - dst[ndst].st_name = bitmap_weight(info->strmap, - dst[ndst].st_name); - ++ndst; + dst[ndst++].st_name = s - mod->core_strtab; + s += strlcpy(s, &mod->strtab[src->st_name], KSYM_NAME_LEN) + 1; } mod->core_num_syms = ndst; - - mod->core_strtab = s = mod->module_core + info->stroffs; - for (*s = 0, i = 1; i < info->sechdrs[info->index.str].sh_size; ++i) - if (test_bit(i, info->strmap)) - *++s = mod->strtab[i]; } #else static inline void layout_symtab(struct module *mod, struct load_info *info) @@ -2621,7 +2660,7 @@ static int move_module(struct module *mod, struct load_info *info) mod->module_init = ptr; /* Transfer each section which specifies SHF_ALLOC */ - DEBUGP("final section addresses:\n"); + pr_debug("final section addresses:\n"); for (i = 0; i < info->hdr->e_shnum; i++) { void *dest; Elf_Shdr *shdr = &info->sechdrs[i]; @@ -2639,8 +2678,8 @@ static int move_module(struct module *mod, struct load_info *info) memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size); /* Update sh_addr to point to copy in image. */ shdr->sh_addr = (unsigned long)dest; - DEBUGP("\t0x%lx %s\n", - shdr->sh_addr, info->secstrings + shdr->sh_name); + pr_debug("\t0x%lx %s\n", + (long)shdr->sh_addr, info->secstrings + shdr->sh_name); } return 0; @@ -2742,27 +2781,18 @@ static struct module *layout_and_allocate(struct load_info *info) this is done generically; there doesn't appear to be any special cases for the architectures. */ layout_sections(mod, info); - - info->strmap = kzalloc(BITS_TO_LONGS(info->sechdrs[info->index.str].sh_size) - * sizeof(long), GFP_KERNEL); - if (!info->strmap) { - err = -ENOMEM; - goto free_percpu; - } layout_symtab(mod, info); /* Allocate and move to the final place */ err = move_module(mod, info); if (err) - goto free_strmap; + goto free_percpu; /* Module has been copied to its final place now: return it. */ mod = (void *)info->sechdrs[info->index.mod].sh_addr; kmemleak_load_module(mod, info); return mod; -free_strmap: - kfree(info->strmap); free_percpu: percpu_modfree(mod); out: @@ -2772,7 +2802,6 @@ out: /* mod is no longer valid after this! */ static void module_deallocate(struct module *mod, struct load_info *info) { - kfree(info->strmap); percpu_modfree(mod); module_free(mod, mod->module_init); module_free(mod, mod->module_core); @@ -2811,7 +2840,7 @@ static struct module *load_module(void __user *umod, struct module *mod; long err; - DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n", + pr_debug("load_module: umod=%p, len=%lu, uargs=%p\n", umod, len, uargs); /* Copy in the blobs from userspace, check they are vaguely sane. */ @@ -2902,8 +2931,7 @@ static struct module *load_module(void __user *umod, if (err < 0) goto unlink; - /* Get rid of temporary copy and strmap. */ - kfree(info.strmap); + /* Get rid of temporary copy. */ free_copy(&info); /* Done! */ @@ -3256,20 +3284,7 @@ static char *module_flags(struct module *mod, char *buf) mod->state == MODULE_STATE_GOING || mod->state == MODULE_STATE_COMING) { buf[bx++] = '('; - if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE)) - buf[bx++] = 'P'; - else if (mod->taints & (1 << TAINT_OOT_MODULE)) - buf[bx++] = 'O'; - if (mod->taints & (1 << TAINT_FORCED_MODULE)) - buf[bx++] = 'F'; - if (mod->taints & (1 << TAINT_CRAP)) - buf[bx++] = 'C'; - /* - * TAINT_FORCED_RMMOD: could be added. - * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't - * apply to modules. - */ - + bx += module_flags_taint(mod, buf + bx); /* Show a - for module-is-being-unloaded */ if (mod->state == MODULE_STATE_GOING) buf[bx++] = '-'; diff --git a/kernel/panic.c b/kernel/panic.c index b2659360..80aed44 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -49,6 +49,15 @@ static long no_blink(int state) long (*panic_blink)(int state); EXPORT_SYMBOL(panic_blink); +/* + * Stop ourself in panic -- architecture code may override this + */ +void __weak panic_smp_self_stop(void) +{ + while (1) + cpu_relax(); +} + /** * panic - halt the system * @fmt: The text string to print @@ -57,8 +66,9 @@ EXPORT_SYMBOL(panic_blink); * * This function never returns. */ -NORET_TYPE void panic(const char * fmt, ...) +void panic(const char *fmt, ...) { + static DEFINE_SPINLOCK(panic_lock); static char buf[1024]; va_list args; long i, i_next = 0; @@ -68,8 +78,14 @@ NORET_TYPE void panic(const char * fmt, ...) * It's possible to come here directly from a panic-assertion and * not have preempt disabled. Some functions called from here want * preempt to be disabled. No point enabling it later though... + * + * Only one CPU is allowed to execute the panic code from here. For + * multiple parallel invocations of panic, all other CPUs either + * stop themself or will wait until they are stopped by the 1st CPU + * with smp_send_stop(). */ - preempt_disable(); + if (!spin_trylock(&panic_lock)) + panic_smp_self_stop(); console_verbose(); bust_spinlocks(1); @@ -78,7 +94,11 @@ NORET_TYPE void panic(const char * fmt, ...) va_end(args); printk(KERN_EMERG "Kernel panic - not syncing: %s\n",buf); #ifdef CONFIG_DEBUG_BUGVERBOSE - dump_stack(); + /* + * Avoid nested stack-dumping if a panic occurs during oops processing + */ + if (!oops_in_progress) + dump_stack(); #endif /* @@ -237,11 +257,20 @@ void add_taint(unsigned flag) * Can't trust the integrity of the kernel anymore. * We don't call directly debug_locks_off() because the issue * is not necessarily serious enough to set oops_in_progress to 1 - * Also we want to keep up lockdep for staging development and - * post-warning case. + * Also we want to keep up lockdep for staging/out-of-tree + * development and post-warning case. */ - if (flag != TAINT_CRAP && flag != TAINT_WARN && __debug_locks_off()) - printk(KERN_WARNING "Disabling lock debugging due to kernel taint\n"); + switch (flag) { + case TAINT_CRAP: + case TAINT_OOT_MODULE: + case TAINT_WARN: + case TAINT_FIRMWARE_WORKAROUND: + break; + + default: + if (__debug_locks_off()) + printk(KERN_WARNING "Disabling lock debugging due to kernel taint\n"); + } set_bit(flag, &tainted_mask); } diff --git a/kernel/params.c b/kernel/params.c index 65aae11e..32ee043 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -25,12 +25,6 @@ #include <linux/slab.h> #include <linux/ctype.h> -#if 0 -#define DEBUGP printk -#else -#define DEBUGP(fmt, a...) -#endif - /* Protects all parameters, and incidentally kmalloced_param list. */ static DEFINE_MUTEX(param_lock); @@ -105,7 +99,7 @@ static int parse_one(char *param, /* No one handled NULL, so do it here. */ if (!val && params[i].ops->set != param_set_bool) return -EINVAL; - DEBUGP("They are equal! Calling %p\n", + pr_debug("They are equal! Calling %p\n", params[i].ops->set); mutex_lock(¶m_lock); err = params[i].ops->set(val, ¶ms[i]); @@ -115,11 +109,11 @@ static int parse_one(char *param, } if (handle_unknown) { - DEBUGP("Unknown argument: calling %p\n", handle_unknown); + pr_debug("Unknown argument: calling %p\n", handle_unknown); return handle_unknown(param, val); } - DEBUGP("Unknown argument `%s'\n", param); + pr_debug("Unknown argument `%s'\n", param); return -ENOENT; } @@ -184,7 +178,7 @@ int parse_args(const char *name, { char *param, *val; - DEBUGP("Parsing ARGS: %s\n", args); + pr_debug("Parsing ARGS: %s\n", args); /* Chew leading spaces */ args = skip_spaces(args); @@ -369,6 +363,30 @@ struct kernel_param_ops param_ops_invbool = { }; EXPORT_SYMBOL(param_ops_invbool); +int param_set_bint(const char *val, const struct kernel_param *kp) +{ + struct kernel_param boolkp; + bool v; + int ret; + + /* Match bool exactly, by re-using it. */ + boolkp = *kp; + boolkp.arg = &v; + boolkp.flags |= KPARAM_ISBOOL; + + ret = param_set_bool(val, &boolkp); + if (ret == 0) + *(int *)kp->arg = v; + return ret; +} +EXPORT_SYMBOL(param_set_bint); + +struct kernel_param_ops param_ops_bint = { + .set = param_set_bint, + .get = param_get_int, +}; +EXPORT_SYMBOL(param_ops_bint); + /* We break the rule and mangle the string. */ static int param_array(const char *name, const char *val, diff --git a/kernel/pid.c b/kernel/pid.c index fa5f722..ce8e00d 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -137,7 +137,9 @@ static int pid_before(int base, int a, int b) } /* - * We might be racing with someone else trying to set pid_ns->last_pid. + * We might be racing with someone else trying to set pid_ns->last_pid + * at the pid allocation time (there's also a sysctl for this, but racing + * with this one is OK, see comment in kernel/pid_namespace.c about it). * We want the winner to have the "later" value, because if the * "earlier" value prevails, then a pid may get reused immediately. * diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index e9c9adc..a896839 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -191,9 +191,40 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns) return; } +static int pid_ns_ctl_handler(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos) +{ + struct ctl_table tmp = *table; + + if (write && !capable(CAP_SYS_ADMIN)) + return -EPERM; + + /* + * Writing directly to ns' last_pid field is OK, since this field + * is volatile in a living namespace anyway and a code writing to + * it should synchronize its usage with external means. + */ + + tmp.data = ¤t->nsproxy->pid_ns->last_pid; + return proc_dointvec(&tmp, write, buffer, lenp, ppos); +} + +static struct ctl_table pid_ns_ctl_table[] = { + { + .procname = "ns_last_pid", + .maxlen = sizeof(int), + .mode = 0666, /* permissions are checked in the handler */ + .proc_handler = pid_ns_ctl_handler, + }, + { } +}; + +static struct ctl_path kern_path[] = { { .procname = "kernel", }, { } }; + static __init int pid_namespaces_init(void) { pid_ns_cachep = KMEM_CACHE(pid_namespace, SLAB_PANIC); + register_sysctl_paths(kern_path, pid_ns_ctl_table); return 0; } diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index e7cb76d..125cb67 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -78,7 +78,7 @@ static inline int cpu_time_before(const clockid_t which_clock, if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) { return now.sched < then.sched; } else { - return cputime_lt(now.cpu, then.cpu); + return now.cpu < then.cpu; } } static inline void cpu_time_add(const clockid_t which_clock, @@ -88,7 +88,7 @@ static inline void cpu_time_add(const clockid_t which_clock, if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) { acc->sched += val.sched; } else { - acc->cpu = cputime_add(acc->cpu, val.cpu); + acc->cpu += val.cpu; } } static inline union cpu_time_count cpu_time_sub(const clockid_t which_clock, @@ -98,25 +98,12 @@ static inline union cpu_time_count cpu_time_sub(const clockid_t which_clock, if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) { a.sched -= b.sched; } else { - a.cpu = cputime_sub(a.cpu, b.cpu); + a.cpu -= b.cpu; } return a; } /* - * Divide and limit the result to res >= 1 - * - * This is necessary to prevent signal delivery starvation, when the result of - * the division would be rounded down to 0. - */ -static inline cputime_t cputime_div_non_zero(cputime_t time, unsigned long div) -{ - cputime_t res = cputime_div(time, div); - - return max_t(cputime_t, res, 1); -} - -/* * Update expiry time from increment, and increase overrun count, * given the current clock sample. */ @@ -148,28 +135,26 @@ static void bump_cpu_timer(struct k_itimer *timer, } else { cputime_t delta, incr; - if (cputime_lt(now.cpu, timer->it.cpu.expires.cpu)) + if (now.cpu < timer->it.cpu.expires.cpu) return; incr = timer->it.cpu.incr.cpu; - delta = cputime_sub(cputime_add(now.cpu, incr), - timer->it.cpu.expires.cpu); + delta = now.cpu + incr - timer->it.cpu.expires.cpu; /* Don't use (incr*2 < delta), incr*2 might overflow. */ - for (i = 0; cputime_lt(incr, cputime_sub(delta, incr)); i++) - incr = cputime_add(incr, incr); - for (; i >= 0; incr = cputime_halve(incr), i--) { - if (cputime_lt(delta, incr)) + for (i = 0; incr < delta - incr; i++) + incr += incr; + for (; i >= 0; incr = incr >> 1, i--) { + if (delta < incr) continue; - timer->it.cpu.expires.cpu = - cputime_add(timer->it.cpu.expires.cpu, incr); + timer->it.cpu.expires.cpu += incr; timer->it_overrun += 1 << i; - delta = cputime_sub(delta, incr); + delta -= incr; } } } static inline cputime_t prof_ticks(struct task_struct *p) { - return cputime_add(p->utime, p->stime); + return p->utime + p->stime; } static inline cputime_t virt_ticks(struct task_struct *p) { @@ -248,8 +233,8 @@ void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times) t = tsk; do { - times->utime = cputime_add(times->utime, t->utime); - times->stime = cputime_add(times->stime, t->stime); + times->utime += t->utime; + times->stime += t->stime; times->sum_exec_runtime += task_sched_runtime(t); } while_each_thread(tsk, t); out: @@ -258,10 +243,10 @@ out: static void update_gt_cputime(struct task_cputime *a, struct task_cputime *b) { - if (cputime_gt(b->utime, a->utime)) + if (b->utime > a->utime) a->utime = b->utime; - if (cputime_gt(b->stime, a->stime)) + if (b->stime > a->stime) a->stime = b->stime; if (b->sum_exec_runtime > a->sum_exec_runtime) @@ -306,7 +291,7 @@ static int cpu_clock_sample_group(const clockid_t which_clock, return -EINVAL; case CPUCLOCK_PROF: thread_group_cputime(p, &cputime); - cpu->cpu = cputime_add(cputime.utime, cputime.stime); + cpu->cpu = cputime.utime + cputime.stime; break; case CPUCLOCK_VIRT: thread_group_cputime(p, &cputime); @@ -470,26 +455,24 @@ static void cleanup_timers(struct list_head *head, unsigned long long sum_exec_runtime) { struct cpu_timer_list *timer, *next; - cputime_t ptime = cputime_add(utime, stime); + cputime_t ptime = utime + stime; list_for_each_entry_safe(timer, next, head, entry) { list_del_init(&timer->entry); - if (cputime_lt(timer->expires.cpu, ptime)) { - timer->expires.cpu = cputime_zero; + if (timer->expires.cpu < ptime) { + timer->expires.cpu = 0; } else { - timer->expires.cpu = cputime_sub(timer->expires.cpu, - ptime); + timer->expires.cpu -= ptime; } } ++head; list_for_each_entry_safe(timer, next, head, entry) { list_del_init(&timer->entry); - if (cputime_lt(timer->expires.cpu, utime)) { - timer->expires.cpu = cputime_zero; + if (timer->expires.cpu < utime) { + timer->expires.cpu = 0; } else { - timer->expires.cpu = cputime_sub(timer->expires.cpu, - utime); + timer->expires.cpu -= utime; } } @@ -520,8 +503,7 @@ void posix_cpu_timers_exit_group(struct task_struct *tsk) struct signal_struct *const sig = tsk->signal; cleanup_timers(tsk->signal->cpu_timers, - cputime_add(tsk->utime, sig->utime), - cputime_add(tsk->stime, sig->stime), + tsk->utime + sig->utime, tsk->stime + sig->stime, tsk->se.sum_exec_runtime + sig->sum_sched_runtime); } @@ -540,8 +522,7 @@ static void clear_dead_task(struct k_itimer *timer, union cpu_time_count now) static inline int expires_gt(cputime_t expires, cputime_t new_exp) { - return cputime_eq(expires, cputime_zero) || - cputime_gt(expires, new_exp); + return expires == 0 || expires > new_exp; } /* @@ -651,7 +632,7 @@ static int cpu_timer_sample_group(const clockid_t which_clock, default: return -EINVAL; case CPUCLOCK_PROF: - cpu->cpu = cputime_add(cputime.utime, cputime.stime); + cpu->cpu = cputime.utime + cputime.stime; break; case CPUCLOCK_VIRT: cpu->cpu = cputime.utime; @@ -918,12 +899,12 @@ static void check_thread_timers(struct task_struct *tsk, unsigned long soft; maxfire = 20; - tsk->cputime_expires.prof_exp = cputime_zero; + tsk->cputime_expires.prof_exp = 0; while (!list_empty(timers)) { struct cpu_timer_list *t = list_first_entry(timers, struct cpu_timer_list, entry); - if (!--maxfire || cputime_lt(prof_ticks(tsk), t->expires.cpu)) { + if (!--maxfire || prof_ticks(tsk) < t->expires.cpu) { tsk->cputime_expires.prof_exp = t->expires.cpu; break; } @@ -933,12 +914,12 @@ static void check_thread_timers(struct task_struct *tsk, ++timers; maxfire = 20; - tsk->cputime_expires.virt_exp = cputime_zero; + tsk->cputime_expires.virt_exp = 0; while (!list_empty(timers)) { struct cpu_timer_list *t = list_first_entry(timers, struct cpu_timer_list, entry); - if (!--maxfire || cputime_lt(virt_ticks(tsk), t->expires.cpu)) { + if (!--maxfire || virt_ticks(tsk) < t->expires.cpu) { tsk->cputime_expires.virt_exp = t->expires.cpu; break; } @@ -1009,20 +990,19 @@ 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)) + if (!it->expires) return; - if (cputime_ge(cur_time, it->expires)) { - if (!cputime_eq(it->incr, cputime_zero)) { - it->expires = cputime_add(it->expires, it->incr); + if (cur_time >= it->expires) { + if (it->incr) { + it->expires += it->incr; it->error += it->incr_error; if (it->error >= onecputick) { - it->expires = cputime_sub(it->expires, - cputime_one_jiffy); + it->expires -= cputime_one_jiffy; it->error -= onecputick; } } else { - it->expires = cputime_zero; + it->expires = 0; } trace_itimer_expire(signo == SIGPROF ? @@ -1031,9 +1011,7 @@ static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it, __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))) { + if (it->expires && (!*expires || it->expires < *expires)) { *expires = it->expires; } } @@ -1048,9 +1026,7 @@ static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it, */ static inline int task_cputime_zero(const struct task_cputime *cputime) { - if (cputime_eq(cputime->utime, cputime_zero) && - cputime_eq(cputime->stime, cputime_zero) && - cputime->sum_exec_runtime == 0) + if (!cputime->utime && !cputime->stime && !cputime->sum_exec_runtime) return 1; return 0; } @@ -1076,15 +1052,15 @@ static void check_process_timers(struct task_struct *tsk, */ thread_group_cputimer(tsk, &cputime); utime = cputime.utime; - ptime = cputime_add(utime, cputime.stime); + ptime = utime + cputime.stime; sum_sched_runtime = cputime.sum_exec_runtime; maxfire = 20; - prof_expires = cputime_zero; + prof_expires = 0; while (!list_empty(timers)) { struct cpu_timer_list *tl = list_first_entry(timers, struct cpu_timer_list, entry); - if (!--maxfire || cputime_lt(ptime, tl->expires.cpu)) { + if (!--maxfire || ptime < tl->expires.cpu) { prof_expires = tl->expires.cpu; break; } @@ -1094,12 +1070,12 @@ static void check_process_timers(struct task_struct *tsk, ++timers; maxfire = 20; - virt_expires = cputime_zero; + virt_expires = 0; while (!list_empty(timers)) { struct cpu_timer_list *tl = list_first_entry(timers, struct cpu_timer_list, entry); - if (!--maxfire || cputime_lt(utime, tl->expires.cpu)) { + if (!--maxfire || utime < tl->expires.cpu) { virt_expires = tl->expires.cpu; break; } @@ -1154,8 +1130,7 @@ static void check_process_timers(struct task_struct *tsk, } } x = secs_to_cputime(soft); - if (cputime_eq(prof_expires, cputime_zero) || - cputime_lt(x, prof_expires)) { + if (!prof_expires || x < prof_expires) { prof_expires = x; } } @@ -1249,12 +1224,9 @@ out: static inline int task_cputime_expired(const struct task_cputime *sample, const struct task_cputime *expires) { - if (!cputime_eq(expires->utime, cputime_zero) && - cputime_ge(sample->utime, expires->utime)) + if (expires->utime && sample->utime >= expires->utime) return 1; - if (!cputime_eq(expires->stime, cputime_zero) && - cputime_ge(cputime_add(sample->utime, sample->stime), - expires->stime)) + if (expires->stime && sample->utime + sample->stime >= expires->stime) return 1; if (expires->sum_exec_runtime != 0 && sample->sum_exec_runtime >= expires->sum_exec_runtime) @@ -1389,18 +1361,18 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx, * it to be relative, *newval argument is relative and we update * it to be absolute. */ - if (!cputime_eq(*oldval, cputime_zero)) { - if (cputime_le(*oldval, now.cpu)) { + if (*oldval) { + if (*oldval <= now.cpu) { /* Just about to fire. */ *oldval = cputime_one_jiffy; } else { - *oldval = cputime_sub(*oldval, now.cpu); + *oldval -= now.cpu; } } - if (cputime_eq(*newval, cputime_zero)) + if (!*newval) return; - *newval = cputime_add(*newval, now.cpu); + *newval += now.cpu; } /* diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index a6b0503..6d6d288 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -43,8 +43,6 @@ int in_suspend __nosavedata; enum { HIBERNATION_INVALID, HIBERNATION_PLATFORM, - HIBERNATION_TEST, - HIBERNATION_TESTPROC, HIBERNATION_SHUTDOWN, HIBERNATION_REBOOT, /* keep last */ @@ -55,7 +53,7 @@ enum { static int hibernation_mode = HIBERNATION_SHUTDOWN; -static bool freezer_test_done; +bool freezer_test_done; static const struct platform_hibernation_ops *hibernation_ops; @@ -71,14 +69,14 @@ void hibernation_set_ops(const struct platform_hibernation_ops *ops) WARN_ON(1); return; } - mutex_lock(&pm_mutex); + lock_system_sleep(); hibernation_ops = ops; if (ops) hibernation_mode = HIBERNATION_PLATFORM; else if (hibernation_mode == HIBERNATION_PLATFORM) hibernation_mode = HIBERNATION_SHUTDOWN; - mutex_unlock(&pm_mutex); + unlock_system_sleep(); } static bool entering_platform_hibernation; @@ -96,15 +94,6 @@ static void hibernation_debug_sleep(void) mdelay(5000); } -static int hibernation_testmode(int mode) -{ - if (hibernation_mode == mode) { - hibernation_debug_sleep(); - return 1; - } - return 0; -} - static int hibernation_test(int level) { if (pm_test_level == level) { @@ -114,7 +103,6 @@ static int hibernation_test(int level) return 0; } #else /* !CONFIG_PM_DEBUG */ -static int hibernation_testmode(int mode) { return 0; } static int hibernation_test(int level) { return 0; } #endif /* !CONFIG_PM_DEBUG */ @@ -278,8 +266,7 @@ static int create_image(int platform_mode) goto Platform_finish; error = disable_nonboot_cpus(); - if (error || hibernation_test(TEST_CPUS) - || hibernation_testmode(HIBERNATION_TEST)) + if (error || hibernation_test(TEST_CPUS)) goto Enable_cpus; local_irq_disable(); @@ -333,7 +320,7 @@ static int create_image(int platform_mode) */ int hibernation_snapshot(int platform_mode) { - pm_message_t msg = PMSG_RECOVER; + pm_message_t msg; int error; error = platform_begin(platform_mode); @@ -349,8 +336,7 @@ int hibernation_snapshot(int platform_mode) if (error) goto Cleanup; - if (hibernation_test(TEST_FREEZER) || - hibernation_testmode(HIBERNATION_TESTPROC)) { + if (hibernation_test(TEST_FREEZER)) { /* * Indicate to the caller that we are returning due to a @@ -362,26 +348,26 @@ int hibernation_snapshot(int platform_mode) error = dpm_prepare(PMSG_FREEZE); if (error) { - dpm_complete(msg); + dpm_complete(PMSG_RECOVER); goto Cleanup; } suspend_console(); pm_restrict_gfp_mask(); + error = dpm_suspend(PMSG_FREEZE); - if (error) - goto Recover_platform; - if (hibernation_test(TEST_DEVICES)) - goto Recover_platform; + if (error || hibernation_test(TEST_DEVICES)) + platform_recover(platform_mode); + else + error = create_image(platform_mode); - error = create_image(platform_mode); /* - * Control returns here (1) after the image has been created or the + * In the case that we call create_image() above, the control + * returns here (1) after the image has been created or the * image creation has failed and (2) after a successful restore. */ - Resume_devices: /* We may need to release the preallocated image pages here. */ if (error || !in_suspend) swsusp_free(); @@ -399,10 +385,6 @@ int hibernation_snapshot(int platform_mode) platform_end(platform_mode); return error; - Recover_platform: - platform_recover(platform_mode); - goto Resume_devices; - Cleanup: swsusp_free(); goto Close; @@ -590,9 +572,6 @@ int hibernation_platform_enter(void) static void power_down(void) { switch (hibernation_mode) { - case HIBERNATION_TEST: - case HIBERNATION_TESTPROC: - break; case HIBERNATION_REBOOT: kernel_restart(NULL); break; @@ -611,17 +590,6 @@ static void power_down(void) while(1); } -static int prepare_processes(void) -{ - int error = 0; - - if (freeze_processes()) { - error = -EBUSY; - thaw_processes(); - } - return error; -} - /** * hibernate - Carry out system hibernation, including saving the image. */ @@ -629,7 +597,7 @@ int hibernate(void) { int error; - mutex_lock(&pm_mutex); + lock_system_sleep(); /* The snapshot device should not be opened while we're running */ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { error = -EBUSY; @@ -654,7 +622,7 @@ int hibernate(void) sys_sync(); printk("done.\n"); - error = prepare_processes(); + error = freeze_processes(); if (error) goto Finish; @@ -697,7 +665,7 @@ int hibernate(void) pm_restore_console(); atomic_inc(&snapshot_device_available); Unlock: - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return error; } @@ -811,11 +779,13 @@ static int software_resume(void) goto close_finish; error = create_basic_memory_bitmaps(); - if (error) + if (error) { + usermodehelper_enable(); goto close_finish; + } pr_debug("PM: Preparing processes for restore.\n"); - error = prepare_processes(); + error = freeze_processes(); if (error) { swsusp_close(FMODE_READ); goto Done; @@ -855,8 +825,6 @@ static const char * const hibernation_modes[] = { [HIBERNATION_PLATFORM] = "platform", [HIBERNATION_SHUTDOWN] = "shutdown", [HIBERNATION_REBOOT] = "reboot", - [HIBERNATION_TEST] = "test", - [HIBERNATION_TESTPROC] = "testproc", }; /* @@ -865,17 +833,15 @@ static const char * const hibernation_modes[] = { * Hibernation can be handled in several ways. There are a few different ways * to put the system into the sleep state: using the platform driver (e.g. ACPI * or other hibernation_ops), powering it off or rebooting it (for testing - * mostly), or using one of the two available test modes. + * mostly). * * The sysfs file /sys/power/disk provides an interface for selecting the * hibernation mode to use. Reading from this file causes the available modes - * to be printed. There are 5 modes that can be supported: + * to be printed. There are 3 modes that can be supported: * * 'platform' * 'shutdown' * 'reboot' - * 'test' - * 'testproc' * * If a platform hibernation driver is in use, 'platform' will be supported * and will be used by default. Otherwise, 'shutdown' will be used by default. @@ -899,8 +865,6 @@ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr, switch (i) { case HIBERNATION_SHUTDOWN: case HIBERNATION_REBOOT: - case HIBERNATION_TEST: - case HIBERNATION_TESTPROC: break; case HIBERNATION_PLATFORM: if (hibernation_ops) @@ -929,7 +893,7 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, p = memchr(buf, '\n', n); len = p ? p - buf : n; - mutex_lock(&pm_mutex); + lock_system_sleep(); for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) { if (len == strlen(hibernation_modes[i]) && !strncmp(buf, hibernation_modes[i], len)) { @@ -941,8 +905,6 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, switch (mode) { case HIBERNATION_SHUTDOWN: case HIBERNATION_REBOOT: - case HIBERNATION_TEST: - case HIBERNATION_TESTPROC: hibernation_mode = mode; break; case HIBERNATION_PLATFORM: @@ -957,7 +919,7 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, if (!error) pr_debug("PM: Hibernation mode set to '%s'\n", hibernation_modes[mode]); - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return error ? error : n; } @@ -984,9 +946,9 @@ static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr, if (maj != MAJOR(res) || min != MINOR(res)) goto out; - mutex_lock(&pm_mutex); + lock_system_sleep(); swsusp_resume_device = res; - mutex_unlock(&pm_mutex); + unlock_system_sleep(); printk(KERN_INFO "PM: Starting manual resume from disk\n"); noresume = 0; software_resume(); diff --git a/kernel/power/main.c b/kernel/power/main.c index 36e0f09..9824b41e 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -3,7 +3,7 @@ * * Copyright (c) 2003 Patrick Mochel * Copyright (c) 2003 Open Source Development Lab - * + * * This file is released under the GPLv2 * */ @@ -116,7 +116,7 @@ static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr, p = memchr(buf, '\n', n); len = p ? p - buf : n; - mutex_lock(&pm_mutex); + lock_system_sleep(); level = TEST_FIRST; for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++) @@ -126,7 +126,7 @@ static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr, break; } - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return error ? error : n; } @@ -240,7 +240,7 @@ struct kobject *power_kobj; * 'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and * 'disk' (Suspend-to-Disk). * - * store() accepts one of those strings, translates it into the + * store() accepts one of those strings, translates it into the * proper enumerated value, and initiates a suspend transition. */ static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, @@ -282,7 +282,7 @@ static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, /* First, check if we are requested to hibernate */ if (len == 4 && !strncmp(buf, "disk", len)) { error = hibernate(); - goto Exit; + goto Exit; } #ifdef CONFIG_SUSPEND diff --git a/kernel/power/power.h b/kernel/power/power.h index 23a2db1..0c4defe 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -50,6 +50,8 @@ static inline char *check_image_kernel(struct swsusp_info *info) #define SPARE_PAGES ((1024 * 1024) >> PAGE_SHIFT) /* kernel/power/hibernate.c */ +extern bool freezer_test_done; + extern int hibernation_snapshot(int platform_mode); extern int hibernation_restore(int platform_mode); extern int hibernation_platform_enter(void); diff --git a/kernel/power/process.c b/kernel/power/process.c index addbbe5..77274c9 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -22,16 +22,7 @@ */ #define TIMEOUT (20 * HZ) -static inline int freezable(struct task_struct * p) -{ - if ((p == current) || - (p->flags & PF_NOFREEZE) || - (p->exit_state != 0)) - return 0; - return 1; -} - -static int try_to_freeze_tasks(bool sig_only) +static int try_to_freeze_tasks(bool user_only) { struct task_struct *g, *p; unsigned long end_time; @@ -46,17 +37,14 @@ static int try_to_freeze_tasks(bool sig_only) end_time = jiffies + TIMEOUT; - if (!sig_only) + if (!user_only) freeze_workqueues_begin(); while (true) { todo = 0; read_lock(&tasklist_lock); do_each_thread(g, p) { - if (frozen(p) || !freezable(p)) - continue; - - if (!freeze_task(p, sig_only)) + if (p == current || !freeze_task(p)) continue; /* @@ -77,7 +65,7 @@ static int try_to_freeze_tasks(bool sig_only) } while_each_thread(g, p); read_unlock(&tasklist_lock); - if (!sig_only) { + if (!user_only) { wq_busy = freeze_workqueues_busy(); todo += wq_busy; } @@ -103,11 +91,6 @@ static int try_to_freeze_tasks(bool sig_only) elapsed_csecs = elapsed_csecs64; if (todo) { - /* This does not unfreeze processes that are already frozen - * (we have slightly ugly calling convention in that respect, - * and caller must call thaw_processes() if something fails), - * but it cleans up leftover PF_FREEZE requests. - */ printk("\n"); printk(KERN_ERR "Freezing of tasks %s after %d.%02d seconds " "(%d tasks refusing to freeze, wq_busy=%d):\n", @@ -115,15 +98,11 @@ static int try_to_freeze_tasks(bool sig_only) elapsed_csecs / 100, elapsed_csecs % 100, todo - wq_busy, wq_busy); - thaw_workqueues(); - read_lock(&tasklist_lock); do_each_thread(g, p) { - task_lock(p); - if (!wakeup && freezing(p) && !freezer_should_skip(p)) + if (!wakeup && !freezer_should_skip(p) && + p != current && freezing(p) && !frozen(p)) sched_show_task(p); - cancel_freezing(p); - task_unlock(p); } while_each_thread(g, p); read_unlock(&tasklist_lock); } else { @@ -136,12 +115,18 @@ static int try_to_freeze_tasks(bool sig_only) /** * freeze_processes - Signal user space processes to enter the refrigerator. + * + * On success, returns 0. On failure, -errno and system is fully thawed. */ int freeze_processes(void) { int error; + if (!pm_freezing) + atomic_inc(&system_freezing_cnt); + printk("Freezing user space processes ... "); + pm_freezing = true; error = try_to_freeze_tasks(true); if (!error) { printk("done."); @@ -150,17 +135,22 @@ int freeze_processes(void) printk("\n"); BUG_ON(in_atomic()); + if (error) + thaw_processes(); return error; } /** * freeze_kernel_threads - Make freezable kernel threads go to the refrigerator. + * + * On success, returns 0. On failure, -errno and system is fully thawed. */ int freeze_kernel_threads(void) { int error; printk("Freezing remaining freezable tasks ... "); + pm_nosig_freezing = true; error = try_to_freeze_tasks(false); if (!error) printk("done."); @@ -168,37 +158,32 @@ int freeze_kernel_threads(void) printk("\n"); BUG_ON(in_atomic()); + if (error) + thaw_processes(); return error; } -static void thaw_tasks(bool nosig_only) +void thaw_processes(void) { struct task_struct *g, *p; - read_lock(&tasklist_lock); - do_each_thread(g, p) { - if (!freezable(p)) - continue; + if (pm_freezing) + atomic_dec(&system_freezing_cnt); + pm_freezing = false; + pm_nosig_freezing = false; - if (nosig_only && should_send_signal(p)) - continue; + oom_killer_enable(); + + printk("Restarting tasks ... "); - if (cgroup_freezing_or_frozen(p)) - continue; + thaw_workqueues(); - thaw_process(p); + read_lock(&tasklist_lock); + do_each_thread(g, p) { + __thaw_task(p); } while_each_thread(g, p); read_unlock(&tasklist_lock); -} -void thaw_processes(void) -{ - oom_killer_enable(); - - printk("Restarting tasks ... "); - thaw_workqueues(); - thaw_tasks(true); - thaw_tasks(false); schedule(); printk("done.\n"); } diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index cbe2c14..1cf8890 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -858,6 +858,9 @@ static struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn) PageReserved(page)) return NULL; + if (page_is_guard(page)) + return NULL; + return page; } @@ -920,6 +923,9 @@ static struct page *saveable_page(struct zone *zone, unsigned long pfn) && (!kernel_page_present(page) || pfn_is_nosave(pfn))) return NULL; + if (page_is_guard(page)) + return NULL; + return page; } diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 4953dc0..4fd51be 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -42,9 +42,9 @@ static const struct platform_suspend_ops *suspend_ops; */ void suspend_set_ops(const struct platform_suspend_ops *ops) { - mutex_lock(&pm_mutex); + lock_system_sleep(); suspend_ops = ops; - mutex_unlock(&pm_mutex); + unlock_system_sleep(); } EXPORT_SYMBOL_GPL(suspend_set_ops); @@ -106,13 +106,11 @@ static int suspend_prepare(void) goto Finish; error = suspend_freeze_processes(); - if (error) { - suspend_stats.failed_freeze++; - dpm_save_failed_step(SUSPEND_FREEZE); - } else + if (!error) return 0; - suspend_thaw_processes(); + suspend_stats.failed_freeze++; + dpm_save_failed_step(SUSPEND_FREEZE); usermodehelper_enable(); Finish: pm_notifier_call_chain(PM_POST_SUSPEND); diff --git a/kernel/power/swap.c b/kernel/power/swap.c index 11a594c..3739ecc 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -18,7 +18,6 @@ #include <linux/bitops.h> #include <linux/genhd.h> #include <linux/device.h> -#include <linux/buffer_head.h> #include <linux/bio.h> #include <linux/blkdev.h> #include <linux/swap.h> diff --git a/kernel/power/user.c b/kernel/power/user.c index 6d8f535..6b1ab7a 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -21,6 +21,7 @@ #include <linux/swapops.h> #include <linux/pm.h> #include <linux/fs.h> +#include <linux/compat.h> #include <linux/console.h> #include <linux/cpu.h> #include <linux/freezer.h> @@ -30,28 +31,6 @@ #include "power.h" -/* - * NOTE: The SNAPSHOT_SET_SWAP_FILE and SNAPSHOT_PMOPS ioctls are obsolete and - * will be removed in the future. They are only preserved here for - * compatibility with existing userland utilities. - */ -#define SNAPSHOT_SET_SWAP_FILE _IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int) -#define SNAPSHOT_PMOPS _IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int) - -#define PMOPS_PREPARE 1 -#define PMOPS_ENTER 2 -#define PMOPS_FINISH 3 - -/* - * NOTE: The following ioctl definitions are wrong and have been replaced with - * correct ones. They are only preserved here for compatibility with existing - * userland utilities and will be removed in the future. - */ -#define SNAPSHOT_ATOMIC_SNAPSHOT _IOW(SNAPSHOT_IOC_MAGIC, 3, void *) -#define SNAPSHOT_SET_IMAGE_SIZE _IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long) -#define SNAPSHOT_AVAIL_SWAP _IOR(SNAPSHOT_IOC_MAGIC, 7, void *) -#define SNAPSHOT_GET_SWAP_PAGE _IOR(SNAPSHOT_IOC_MAGIC, 8, void *) - #define SNAPSHOT_MINOR 231 @@ -71,7 +50,7 @@ static int snapshot_open(struct inode *inode, struct file *filp) struct snapshot_data *data; int error; - mutex_lock(&pm_mutex); + lock_system_sleep(); if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { error = -EBUSY; @@ -123,7 +102,7 @@ static int snapshot_open(struct inode *inode, struct file *filp) data->platform_support = 0; Unlock: - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return error; } @@ -132,7 +111,7 @@ static int snapshot_release(struct inode *inode, struct file *filp) { struct snapshot_data *data; - mutex_lock(&pm_mutex); + lock_system_sleep(); swsusp_free(); free_basic_memory_bitmaps(); @@ -146,7 +125,7 @@ static int snapshot_release(struct inode *inode, struct file *filp) PM_POST_HIBERNATION : PM_POST_RESTORE); atomic_inc(&snapshot_device_available); - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return 0; } @@ -158,7 +137,7 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf, ssize_t res; loff_t pg_offp = *offp & ~PAGE_MASK; - mutex_lock(&pm_mutex); + lock_system_sleep(); data = filp->private_data; if (!data->ready) { @@ -179,7 +158,7 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf, *offp += res; Unlock: - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return res; } @@ -191,7 +170,7 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, ssize_t res; loff_t pg_offp = *offp & ~PAGE_MASK; - mutex_lock(&pm_mutex); + lock_system_sleep(); data = filp->private_data; @@ -208,20 +187,11 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, if (res > 0) *offp += res; unlock: - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return res; } -static void snapshot_deprecated_ioctl(unsigned int cmd) -{ - if (printk_ratelimit()) - printk(KERN_NOTICE "%pf: ioctl '%.8x' is deprecated and will " - "be removed soon, update your suspend-to-disk " - "utilities\n", - __builtin_return_address(0), cmd); -} - static long snapshot_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { @@ -257,11 +227,9 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, break; error = freeze_processes(); - if (error) { - thaw_processes(); + if (error) usermodehelper_enable(); - } - if (!error) + else data->frozen = 1; break; @@ -274,8 +242,6 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, data->frozen = 0; break; - case SNAPSHOT_ATOMIC_SNAPSHOT: - snapshot_deprecated_ioctl(cmd); case SNAPSHOT_CREATE_IMAGE: if (data->mode != O_RDONLY || !data->frozen || data->ready) { error = -EPERM; @@ -283,10 +249,15 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, } pm_restore_gfp_mask(); error = hibernation_snapshot(data->platform_support); - if (!error) + if (!error) { error = put_user(in_suspend, (int __user *)arg); - if (!error) - data->ready = 1; + if (!error && !freezer_test_done) + data->ready = 1; + if (freezer_test_done) { + freezer_test_done = false; + thaw_processes(); + } + } break; case SNAPSHOT_ATOMIC_RESTORE: @@ -305,8 +276,6 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, data->ready = 0; break; - case SNAPSHOT_SET_IMAGE_SIZE: - snapshot_deprecated_ioctl(cmd); case SNAPSHOT_PREF_IMAGE_SIZE: image_size = arg; break; @@ -321,16 +290,12 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, error = put_user(size, (loff_t __user *)arg); break; - case SNAPSHOT_AVAIL_SWAP: - snapshot_deprecated_ioctl(cmd); case SNAPSHOT_AVAIL_SWAP_SIZE: size = count_swap_pages(data->swap, 1); size <<= PAGE_SHIFT; error = put_user(size, (loff_t __user *)arg); break; - case SNAPSHOT_GET_SWAP_PAGE: - snapshot_deprecated_ioctl(cmd); case SNAPSHOT_ALLOC_SWAP_PAGE: if (data->swap < 0 || data->swap >= MAX_SWAPFILES) { error = -ENODEV; @@ -353,27 +318,6 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, free_all_swap_pages(data->swap); break; - case SNAPSHOT_SET_SWAP_FILE: /* This ioctl is deprecated */ - snapshot_deprecated_ioctl(cmd); - if (!swsusp_swap_in_use()) { - /* - * User space encodes device types as two-byte values, - * so we need to recode them - */ - if (old_decode_dev(arg)) { - data->swap = swap_type_of(old_decode_dev(arg), - 0, NULL); - if (data->swap < 0) - error = -ENODEV; - } else { - data->swap = -1; - error = -EINVAL; - } - } else { - error = -EPERM; - } - break; - case SNAPSHOT_S2RAM: if (!data->frozen) { error = -EPERM; @@ -396,33 +340,6 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, error = hibernation_platform_enter(); break; - case SNAPSHOT_PMOPS: /* This ioctl is deprecated */ - snapshot_deprecated_ioctl(cmd); - error = -EINVAL; - - switch (arg) { - - case PMOPS_PREPARE: - data->platform_support = 1; - error = 0; - break; - - case PMOPS_ENTER: - if (data->platform_support) - error = hibernation_platform_enter(); - break; - - case PMOPS_FINISH: - if (data->platform_support) - error = 0; - break; - - default: - printk(KERN_ERR "SNAPSHOT_PMOPS: invalid argument %ld\n", arg); - - } - break; - case SNAPSHOT_SET_SWAP_AREA: if (swsusp_swap_in_use()) { error = -EPERM; @@ -464,6 +381,66 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, return error; } +#ifdef CONFIG_COMPAT + +struct compat_resume_swap_area { + compat_loff_t offset; + u32 dev; +} __packed; + +static long +snapshot_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + BUILD_BUG_ON(sizeof(loff_t) != sizeof(compat_loff_t)); + + switch (cmd) { + case SNAPSHOT_GET_IMAGE_SIZE: + case SNAPSHOT_AVAIL_SWAP_SIZE: + case SNAPSHOT_ALLOC_SWAP_PAGE: { + compat_loff_t __user *uoffset = compat_ptr(arg); + loff_t offset; + mm_segment_t old_fs; + int err; + + old_fs = get_fs(); + set_fs(KERNEL_DS); + err = snapshot_ioctl(file, cmd, (unsigned long) &offset); + set_fs(old_fs); + if (!err && put_user(offset, uoffset)) + err = -EFAULT; + return err; + } + + case SNAPSHOT_CREATE_IMAGE: + return snapshot_ioctl(file, cmd, + (unsigned long) compat_ptr(arg)); + + case SNAPSHOT_SET_SWAP_AREA: { + struct compat_resume_swap_area __user *u_swap_area = + compat_ptr(arg); + struct resume_swap_area swap_area; + mm_segment_t old_fs; + int err; + + err = get_user(swap_area.offset, &u_swap_area->offset); + err |= get_user(swap_area.dev, &u_swap_area->dev); + if (err) + return -EFAULT; + old_fs = get_fs(); + set_fs(KERNEL_DS); + err = snapshot_ioctl(file, SNAPSHOT_SET_SWAP_AREA, + (unsigned long) &swap_area); + set_fs(old_fs); + return err; + } + + default: + return snapshot_ioctl(file, cmd, arg); + } +} + +#endif /* CONFIG_COMPAT */ + static const struct file_operations snapshot_fops = { .open = snapshot_open, .release = snapshot_release, @@ -471,6 +448,9 @@ static const struct file_operations snapshot_fops = { .write = snapshot_write, .llseek = no_llseek, .unlocked_ioctl = snapshot_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = snapshot_compat_ioctl, +#endif }; static struct miscdevice snapshot_device = { diff --git a/kernel/printk.c b/kernel/printk.c index 7982a0a..13c0a11 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -199,7 +199,7 @@ void __init setup_log_buf(int early) unsigned long mem; mem = memblock_alloc(new_log_buf_len, PAGE_SIZE); - if (mem == MEMBLOCK_ERROR) + if (!mem) return; new_log_buf = __va(mem); } else { @@ -521,7 +521,7 @@ static void __call_console_drivers(unsigned start, unsigned end) } } -static int __read_mostly ignore_loglevel; +static bool __read_mostly ignore_loglevel; static int __init ignore_loglevel_setup(char *str) { @@ -532,7 +532,7 @@ static int __init ignore_loglevel_setup(char *str) } early_param("ignore_loglevel", ignore_loglevel_setup); -module_param_named(ignore_loglevel, ignore_loglevel, bool, S_IRUGO | S_IWUSR); +module_param(ignore_loglevel, bool, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(ignore_loglevel, "ignore loglevel setting, to" "print all kernel messages to the console."); @@ -688,6 +688,7 @@ static void zap_locks(void) oops_timestamp = jiffies; + debug_locks_off(); /* If a crash is occurring, make sure we can't deadlock */ raw_spin_lock_init(&logbuf_lock); /* And make sure that we print immediately */ @@ -695,9 +696,9 @@ static void zap_locks(void) } #if defined(CONFIG_PRINTK_TIME) -static int printk_time = 1; +static bool printk_time = 1; #else -static int printk_time = 0; +static bool printk_time = 0; #endif module_param_named(time, printk_time, bool, S_IRUGO | S_IWUSR); @@ -840,9 +841,8 @@ asmlinkage int vprintk(const char *fmt, va_list args) boot_delay_msec(); printk_delay(); - preempt_disable(); /* This stops the holder of console_sem just where we want him */ - raw_local_irq_save(flags); + local_irq_save(flags); this_cpu = smp_processor_id(); /* @@ -856,7 +856,7 @@ asmlinkage int vprintk(const char *fmt, va_list args) * recursion and return - but flag the recursion so that * it can be printed at the next appropriate moment: */ - if (!oops_in_progress) { + if (!oops_in_progress && !lockdep_recursing(current)) { recursion_bug = 1; goto out_restore_irqs; } @@ -962,9 +962,8 @@ asmlinkage int vprintk(const char *fmt, va_list args) lockdep_on(); out_restore_irqs: - raw_local_irq_restore(flags); + local_irq_restore(flags); - preempt_enable(); return printed_len; } EXPORT_SYMBOL(printk); @@ -1099,7 +1098,7 @@ int update_console_cmdline(char *name, int idx, char *name_new, int idx_new, cha return -1; } -int console_suspend_enabled = 1; +bool console_suspend_enabled = 1; EXPORT_SYMBOL(console_suspend_enabled); static int __init console_suspend_disable(char *str) diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 78ab24a..00ab2ca 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -172,6 +172,14 @@ int ptrace_check_attach(struct task_struct *child, bool ignore_state) return ret; } +static int ptrace_has_cap(struct user_namespace *ns, unsigned int mode) +{ + if (mode & PTRACE_MODE_NOAUDIT) + return has_ns_capability_noaudit(current, ns, CAP_SYS_PTRACE); + else + return has_ns_capability(current, ns, CAP_SYS_PTRACE); +} + int __ptrace_may_access(struct task_struct *task, unsigned int mode) { const struct cred *cred = current_cred(), *tcred; @@ -198,7 +206,7 @@ int __ptrace_may_access(struct task_struct *task, unsigned int mode) cred->gid == tcred->sgid && cred->gid == tcred->gid)) goto ok; - if (ns_capable(tcred->user->user_ns, CAP_SYS_PTRACE)) + if (ptrace_has_cap(tcred->user->user_ns, mode)) goto ok; rcu_read_unlock(); return -EPERM; @@ -207,7 +215,7 @@ ok: smp_rmb(); if (task->mm) dumpable = get_dumpable(task->mm); - if (!dumpable && !task_ns_capable(task, CAP_SYS_PTRACE)) + if (!dumpable && !ptrace_has_cap(task_user_ns(task), mode)) return -EPERM; return security_ptrace_access_check(task, mode); @@ -277,7 +285,7 @@ static int ptrace_attach(struct task_struct *task, long request, task->ptrace = PT_PTRACED; if (seize) task->ptrace |= PT_SEIZED; - if (task_ns_capable(task, CAP_SYS_PTRACE)) + if (ns_capable(task_user_ns(task), CAP_SYS_PTRACE)) task->ptrace |= PT_PTRACE_CAP; __ptrace_link(task, current); diff --git a/kernel/rcu.h b/kernel/rcu.h index f600868..aa88baa 100644 --- a/kernel/rcu.h +++ b/kernel/rcu.h @@ -30,6 +30,13 @@ #endif /* #else #ifdef CONFIG_RCU_TRACE */ /* + * Process-level increment to ->dynticks_nesting field. This allows for + * architectures that use half-interrupts and half-exceptions from + * process context. + */ +#define DYNTICK_TASK_NESTING (LLONG_MAX / 2 - 1) + +/* * debug_rcu_head_queue()/debug_rcu_head_unqueue() are used internally * by call_rcu() and rcu callback execution, and are therefore not part of the * RCU API. Leaving in rcupdate.h because they are used by all RCU flavors. diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c index c5b98e5..2bc4e13 100644 --- a/kernel/rcupdate.c +++ b/kernel/rcupdate.c @@ -93,6 +93,8 @@ int rcu_read_lock_bh_held(void) { if (!debug_lockdep_rcu_enabled()) return 1; + if (rcu_is_cpu_idle()) + return 0; return in_softirq() || irqs_disabled(); } EXPORT_SYMBOL_GPL(rcu_read_lock_bh_held); @@ -316,3 +318,13 @@ struct debug_obj_descr rcuhead_debug_descr = { }; EXPORT_SYMBOL_GPL(rcuhead_debug_descr); #endif /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ + +#if defined(CONFIG_TREE_RCU) || defined(CONFIG_TREE_PREEMPT_RCU) || defined(CONFIG_RCU_TRACE) +void do_trace_rcu_torture_read(char *rcutorturename, struct rcu_head *rhp) +{ + trace_rcu_torture_read(rcutorturename, rhp); +} +EXPORT_SYMBOL_GPL(do_trace_rcu_torture_read); +#else +#define do_trace_rcu_torture_read(rcutorturename, rhp) do { } while (0) +#endif diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c index 636af6d..977296d 100644 --- a/kernel/rcutiny.c +++ b/kernel/rcutiny.c @@ -53,31 +53,137 @@ static void __call_rcu(struct rcu_head *head, #include "rcutiny_plugin.h" -#ifdef CONFIG_NO_HZ +static long long rcu_dynticks_nesting = DYNTICK_TASK_NESTING; -static long rcu_dynticks_nesting = 1; +/* Common code for rcu_idle_enter() and rcu_irq_exit(), see kernel/rcutree.c. */ +static void rcu_idle_enter_common(long long oldval) +{ + if (rcu_dynticks_nesting) { + RCU_TRACE(trace_rcu_dyntick("--=", + oldval, rcu_dynticks_nesting)); + return; + } + RCU_TRACE(trace_rcu_dyntick("Start", oldval, rcu_dynticks_nesting)); + if (!is_idle_task(current)) { + struct task_struct *idle = idle_task(smp_processor_id()); + + RCU_TRACE(trace_rcu_dyntick("Error on entry: not idle task", + oldval, rcu_dynticks_nesting)); + ftrace_dump(DUMP_ALL); + WARN_ONCE(1, "Current pid: %d comm: %s / Idle pid: %d comm: %s", + current->pid, current->comm, + idle->pid, idle->comm); /* must be idle task! */ + } + rcu_sched_qs(0); /* implies rcu_bh_qsctr_inc(0) */ +} /* - * Enter dynticks-idle mode, which is an extended quiescent state - * if we have fully entered that mode (i.e., if the new value of - * dynticks_nesting is zero). + * Enter idle, which is an extended quiescent state if we have fully + * entered that mode (i.e., if the new value of dynticks_nesting is zero). */ -void rcu_enter_nohz(void) +void rcu_idle_enter(void) { - if (--rcu_dynticks_nesting == 0) - rcu_sched_qs(0); /* implies rcu_bh_qsctr_inc(0) */ + unsigned long flags; + long long oldval; + + local_irq_save(flags); + oldval = rcu_dynticks_nesting; + rcu_dynticks_nesting = 0; + rcu_idle_enter_common(oldval); + local_irq_restore(flags); } /* - * Exit dynticks-idle mode, so that we are no longer in an extended - * quiescent state. + * Exit an interrupt handler towards idle. */ -void rcu_exit_nohz(void) +void rcu_irq_exit(void) +{ + unsigned long flags; + long long oldval; + + local_irq_save(flags); + oldval = rcu_dynticks_nesting; + rcu_dynticks_nesting--; + WARN_ON_ONCE(rcu_dynticks_nesting < 0); + rcu_idle_enter_common(oldval); + local_irq_restore(flags); +} + +/* Common code for rcu_idle_exit() and rcu_irq_enter(), see kernel/rcutree.c. */ +static void rcu_idle_exit_common(long long oldval) { + if (oldval) { + RCU_TRACE(trace_rcu_dyntick("++=", + oldval, rcu_dynticks_nesting)); + return; + } + RCU_TRACE(trace_rcu_dyntick("End", oldval, rcu_dynticks_nesting)); + if (!is_idle_task(current)) { + struct task_struct *idle = idle_task(smp_processor_id()); + + RCU_TRACE(trace_rcu_dyntick("Error on exit: not idle task", + oldval, rcu_dynticks_nesting)); + ftrace_dump(DUMP_ALL); + WARN_ONCE(1, "Current pid: %d comm: %s / Idle pid: %d comm: %s", + current->pid, current->comm, + idle->pid, idle->comm); /* must be idle task! */ + } +} + +/* + * Exit idle, so that we are no longer in an extended quiescent state. + */ +void rcu_idle_exit(void) +{ + unsigned long flags; + long long oldval; + + local_irq_save(flags); + oldval = rcu_dynticks_nesting; + WARN_ON_ONCE(oldval != 0); + rcu_dynticks_nesting = DYNTICK_TASK_NESTING; + rcu_idle_exit_common(oldval); + local_irq_restore(flags); +} + +/* + * Enter an interrupt handler, moving away from idle. + */ +void rcu_irq_enter(void) +{ + unsigned long flags; + long long oldval; + + local_irq_save(flags); + oldval = rcu_dynticks_nesting; rcu_dynticks_nesting++; + WARN_ON_ONCE(rcu_dynticks_nesting == 0); + rcu_idle_exit_common(oldval); + local_irq_restore(flags); +} + +#ifdef CONFIG_PROVE_RCU + +/* + * Test whether RCU thinks that the current CPU is idle. + */ +int rcu_is_cpu_idle(void) +{ + return !rcu_dynticks_nesting; } +EXPORT_SYMBOL(rcu_is_cpu_idle); + +#endif /* #ifdef CONFIG_PROVE_RCU */ -#endif /* #ifdef CONFIG_NO_HZ */ +/* + * Test whether the current CPU was interrupted from idle. Nested + * interrupts don't count, we must be running at the first interrupt + * level. + */ +int rcu_is_cpu_rrupt_from_idle(void) +{ + return rcu_dynticks_nesting <= 0; +} /* * Helper function for rcu_sched_qs() and rcu_bh_qs(). @@ -126,14 +232,13 @@ void rcu_bh_qs(int cpu) /* * Check to see if the scheduling-clock interrupt came from an extended - * quiescent state, and, if so, tell RCU about it. + * quiescent state, and, if so, tell RCU about it. This function must + * be called from hardirq context. It is normally called from the + * scheduling-clock interrupt. */ void rcu_check_callbacks(int cpu, int user) { - if (user || - (idle_cpu(cpu) && - !in_softirq() && - hardirq_count() <= (1 << HARDIRQ_SHIFT))) + if (user || rcu_is_cpu_rrupt_from_idle()) rcu_sched_qs(cpu); else if (!in_softirq()) rcu_bh_qs(cpu); @@ -154,7 +259,11 @@ static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp) /* If no RCU callbacks ready to invoke, just return. */ if (&rcp->rcucblist == rcp->donetail) { RCU_TRACE(trace_rcu_batch_start(rcp->name, 0, -1)); - RCU_TRACE(trace_rcu_batch_end(rcp->name, 0)); + RCU_TRACE(trace_rcu_batch_end(rcp->name, 0, + ACCESS_ONCE(rcp->rcucblist), + need_resched(), + is_idle_task(current), + rcu_is_callbacks_kthread())); return; } @@ -183,7 +292,9 @@ static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp) RCU_TRACE(cb_count++); } RCU_TRACE(rcu_trace_sub_qlen(rcp, cb_count)); - RCU_TRACE(trace_rcu_batch_end(rcp->name, cb_count)); + RCU_TRACE(trace_rcu_batch_end(rcp->name, cb_count, 0, need_resched(), + is_idle_task(current), + rcu_is_callbacks_kthread())); } static void rcu_process_callbacks(struct softirq_action *unused) diff --git a/kernel/rcutiny_plugin.h b/kernel/rcutiny_plugin.h index 2b0484a..9cb1ae4 100644 --- a/kernel/rcutiny_plugin.h +++ b/kernel/rcutiny_plugin.h @@ -312,8 +312,8 @@ static int rcu_boost(void) rt_mutex_lock(&mtx); rt_mutex_unlock(&mtx); /* Keep lockdep happy. */ - return rcu_preempt_ctrlblk.boost_tasks != NULL || - rcu_preempt_ctrlblk.exp_tasks != NULL; + return ACCESS_ONCE(rcu_preempt_ctrlblk.boost_tasks) != NULL || + ACCESS_ONCE(rcu_preempt_ctrlblk.exp_tasks) != NULL; } /* @@ -885,6 +885,19 @@ static void invoke_rcu_callbacks(void) wake_up(&rcu_kthread_wq); } +#ifdef CONFIG_RCU_TRACE + +/* + * Is the current CPU running the RCU-callbacks kthread? + * Caller must have preemption disabled. + */ +static bool rcu_is_callbacks_kthread(void) +{ + return rcu_kthread_task == current; +} + +#endif /* #ifdef CONFIG_RCU_TRACE */ + /* * This kthread invokes RCU callbacks whose grace periods have * elapsed. It is awakened as needed, and takes the place of the @@ -938,6 +951,18 @@ void invoke_rcu_callbacks(void) raise_softirq(RCU_SOFTIRQ); } +#ifdef CONFIG_RCU_TRACE + +/* + * There is no callback kthread, so this thread is never it. + */ +static bool rcu_is_callbacks_kthread(void) +{ + return false; +} + +#endif /* #ifdef CONFIG_RCU_TRACE */ + void rcu_init(void) { open_softirq(RCU_SOFTIRQ, rcu_process_callbacks); diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index 764825c2..88f17b8 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -61,9 +61,11 @@ static int test_no_idle_hz; /* Test RCU's support for tickless idle CPUs. */ static int shuffle_interval = 3; /* Interval between shuffles (in sec)*/ static int stutter = 5; /* Start/stop testing interval (in sec) */ static int irqreader = 1; /* RCU readers from irq (timers). */ -static int fqs_duration = 0; /* Duration of bursts (us), 0 to disable. */ -static int fqs_holdoff = 0; /* Hold time within burst (us). */ +static int fqs_duration; /* Duration of bursts (us), 0 to disable. */ +static int fqs_holdoff; /* Hold time within burst (us). */ static int fqs_stutter = 3; /* Wait time between bursts (s). */ +static int onoff_interval; /* Wait time between CPU hotplugs, 0=disable. */ +static int shutdown_secs; /* Shutdown time (s). <=0 for no shutdown. */ static int test_boost = 1; /* Test RCU prio boost: 0=no, 1=maybe, 2=yes. */ static int test_boost_interval = 7; /* Interval between boost tests, seconds. */ static int test_boost_duration = 4; /* Duration of each boost test, seconds. */ @@ -91,6 +93,10 @@ module_param(fqs_holdoff, int, 0444); MODULE_PARM_DESC(fqs_holdoff, "Holdoff time within fqs bursts (us)"); module_param(fqs_stutter, int, 0444); MODULE_PARM_DESC(fqs_stutter, "Wait time between fqs bursts (s)"); +module_param(onoff_interval, int, 0444); +MODULE_PARM_DESC(onoff_interval, "Time between CPU hotplugs (s), 0=disable"); +module_param(shutdown_secs, int, 0444); +MODULE_PARM_DESC(shutdown_secs, "Shutdown time (s), zero to disable."); module_param(test_boost, int, 0444); MODULE_PARM_DESC(test_boost, "Test RCU prio boost: 0=no, 1=maybe, 2=yes."); module_param(test_boost_interval, int, 0444); @@ -119,6 +125,10 @@ static struct task_struct *shuffler_task; static struct task_struct *stutter_task; static struct task_struct *fqs_task; static struct task_struct *boost_tasks[NR_CPUS]; +static struct task_struct *shutdown_task; +#ifdef CONFIG_HOTPLUG_CPU +static struct task_struct *onoff_task; +#endif /* #ifdef CONFIG_HOTPLUG_CPU */ #define RCU_TORTURE_PIPE_LEN 10 @@ -149,6 +159,10 @@ static long n_rcu_torture_boost_rterror; static long n_rcu_torture_boost_failure; static long n_rcu_torture_boosts; static long n_rcu_torture_timers; +static long n_offline_attempts; +static long n_offline_successes; +static long n_online_attempts; +static long n_online_successes; static struct list_head rcu_torture_removed; static cpumask_var_t shuffle_tmp_mask; @@ -160,6 +174,8 @@ static int stutter_pause_test; #define RCUTORTURE_RUNNABLE_INIT 0 #endif int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT; +module_param(rcutorture_runnable, int, 0444); +MODULE_PARM_DESC(rcutorture_runnable, "Start rcutorture at boot"); #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) #define rcu_can_boost() 1 @@ -167,6 +183,7 @@ int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT; #define rcu_can_boost() 0 #endif /* #else #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ +static unsigned long shutdown_time; /* jiffies to system shutdown. */ static unsigned long boost_starttime; /* jiffies of next boost test start. */ DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */ /* and boost task create/destroy. */ @@ -182,6 +199,9 @@ static int fullstop = FULLSTOP_RMMOD; */ static DEFINE_MUTEX(fullstop_mutex); +/* Forward reference. */ +static void rcu_torture_cleanup(void); + /* * Detect and respond to a system shutdown. */ @@ -612,6 +632,30 @@ static struct rcu_torture_ops srcu_ops = { .name = "srcu" }; +static int srcu_torture_read_lock_raw(void) __acquires(&srcu_ctl) +{ + return srcu_read_lock_raw(&srcu_ctl); +} + +static void srcu_torture_read_unlock_raw(int idx) __releases(&srcu_ctl) +{ + srcu_read_unlock_raw(&srcu_ctl, idx); +} + +static struct rcu_torture_ops srcu_raw_ops = { + .init = srcu_torture_init, + .cleanup = srcu_torture_cleanup, + .readlock = srcu_torture_read_lock_raw, + .read_delay = srcu_read_delay, + .readunlock = srcu_torture_read_unlock_raw, + .completed = srcu_torture_completed, + .deferred_free = rcu_sync_torture_deferred_free, + .sync = srcu_torture_synchronize, + .cb_barrier = NULL, + .stats = srcu_torture_stats, + .name = "srcu_raw" +}; + static void srcu_torture_synchronize_expedited(void) { synchronize_srcu_expedited(&srcu_ctl); @@ -913,6 +957,18 @@ rcu_torture_fakewriter(void *arg) return 0; } +void rcutorture_trace_dump(void) +{ + static atomic_t beenhere = ATOMIC_INIT(0); + + if (atomic_read(&beenhere)) + return; + if (atomic_xchg(&beenhere, 1) != 0) + return; + do_trace_rcu_torture_read(cur_ops->name, (struct rcu_head *)~0UL); + ftrace_dump(DUMP_ALL); +} + /* * RCU torture reader from timer handler. Dereferences rcu_torture_current, * incrementing the corresponding element of the pipeline array. The @@ -934,6 +990,7 @@ static void rcu_torture_timer(unsigned long unused) rcu_read_lock_bh_held() || rcu_read_lock_sched_held() || srcu_read_lock_held(&srcu_ctl)); + do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu); if (p == NULL) { /* Leave because rcu_torture_writer is not yet underway */ cur_ops->readunlock(idx); @@ -951,6 +1008,8 @@ static void rcu_torture_timer(unsigned long unused) /* Should not happen, but... */ pipe_count = RCU_TORTURE_PIPE_LEN; } + if (pipe_count > 1) + rcutorture_trace_dump(); __this_cpu_inc(rcu_torture_count[pipe_count]); completed = cur_ops->completed() - completed; if (completed > RCU_TORTURE_PIPE_LEN) { @@ -994,6 +1053,7 @@ rcu_torture_reader(void *arg) rcu_read_lock_bh_held() || rcu_read_lock_sched_held() || srcu_read_lock_held(&srcu_ctl)); + do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu); if (p == NULL) { /* Wait for rcu_torture_writer to get underway */ cur_ops->readunlock(idx); @@ -1009,6 +1069,8 @@ rcu_torture_reader(void *arg) /* Should not happen, but... */ pipe_count = RCU_TORTURE_PIPE_LEN; } + if (pipe_count > 1) + rcutorture_trace_dump(); __this_cpu_inc(rcu_torture_count[pipe_count]); completed = cur_ops->completed() - completed; if (completed > RCU_TORTURE_PIPE_LEN) { @@ -1056,7 +1118,8 @@ rcu_torture_printk(char *page) cnt += sprintf(&page[cnt], "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d " "rtmbe: %d rtbke: %ld rtbre: %ld " - "rtbf: %ld rtb: %ld nt: %ld", + "rtbf: %ld rtb: %ld nt: %ld " + "onoff: %ld/%ld:%ld/%ld", rcu_torture_current, rcu_torture_current_version, list_empty(&rcu_torture_freelist), @@ -1068,7 +1131,11 @@ rcu_torture_printk(char *page) n_rcu_torture_boost_rterror, n_rcu_torture_boost_failure, n_rcu_torture_boosts, - n_rcu_torture_timers); + n_rcu_torture_timers, + n_online_successes, + n_online_attempts, + n_offline_successes, + n_offline_attempts); if (atomic_read(&n_rcu_torture_mberror) != 0 || n_rcu_torture_boost_ktrerror != 0 || n_rcu_torture_boost_rterror != 0 || @@ -1232,12 +1299,14 @@ rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, char *tag) "shuffle_interval=%d stutter=%d irqreader=%d " "fqs_duration=%d fqs_holdoff=%d fqs_stutter=%d " "test_boost=%d/%d test_boost_interval=%d " - "test_boost_duration=%d\n", + "test_boost_duration=%d shutdown_secs=%d " + "onoff_interval=%d\n", torture_type, tag, nrealreaders, nfakewriters, stat_interval, verbose, test_no_idle_hz, shuffle_interval, stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter, test_boost, cur_ops->can_boost, - test_boost_interval, test_boost_duration); + test_boost_interval, test_boost_duration, shutdown_secs, + onoff_interval); } static struct notifier_block rcutorture_shutdown_nb = { @@ -1287,6 +1356,131 @@ static int rcutorture_booster_init(int cpu) return 0; } +/* + * Cause the rcutorture test to shutdown the system after the test has + * run for the time specified by the shutdown_secs module parameter. + */ +static int +rcu_torture_shutdown(void *arg) +{ + long delta; + unsigned long jiffies_snap; + + VERBOSE_PRINTK_STRING("rcu_torture_shutdown task started"); + jiffies_snap = ACCESS_ONCE(jiffies); + while (ULONG_CMP_LT(jiffies_snap, shutdown_time) && + !kthread_should_stop()) { + delta = shutdown_time - jiffies_snap; + if (verbose) + printk(KERN_ALERT "%s" TORTURE_FLAG + "rcu_torture_shutdown task: %lu " + "jiffies remaining\n", + torture_type, delta); + schedule_timeout_interruptible(delta); + jiffies_snap = ACCESS_ONCE(jiffies); + } + if (kthread_should_stop()) { + VERBOSE_PRINTK_STRING("rcu_torture_shutdown task stopping"); + return 0; + } + + /* OK, shut down the system. */ + + VERBOSE_PRINTK_STRING("rcu_torture_shutdown task shutting down system"); + shutdown_task = NULL; /* Avoid self-kill deadlock. */ + rcu_torture_cleanup(); /* Get the success/failure message. */ + kernel_power_off(); /* Shut down the system. */ + return 0; +} + +#ifdef CONFIG_HOTPLUG_CPU + +/* + * Execute random CPU-hotplug operations at the interval specified + * by the onoff_interval. + */ +static int +rcu_torture_onoff(void *arg) +{ + int cpu; + int maxcpu = -1; + DEFINE_RCU_RANDOM(rand); + + VERBOSE_PRINTK_STRING("rcu_torture_onoff task started"); + for_each_online_cpu(cpu) + maxcpu = cpu; + WARN_ON(maxcpu < 0); + while (!kthread_should_stop()) { + cpu = (rcu_random(&rand) >> 4) % (maxcpu + 1); + if (cpu_online(cpu) && cpu_is_hotpluggable(cpu)) { + if (verbose) + printk(KERN_ALERT "%s" TORTURE_FLAG + "rcu_torture_onoff task: offlining %d\n", + torture_type, cpu); + n_offline_attempts++; + if (cpu_down(cpu) == 0) { + if (verbose) + printk(KERN_ALERT "%s" TORTURE_FLAG + "rcu_torture_onoff task: " + "offlined %d\n", + torture_type, cpu); + n_offline_successes++; + } + } else if (cpu_is_hotpluggable(cpu)) { + if (verbose) + printk(KERN_ALERT "%s" TORTURE_FLAG + "rcu_torture_onoff task: onlining %d\n", + torture_type, cpu); + n_online_attempts++; + if (cpu_up(cpu) == 0) { + if (verbose) + printk(KERN_ALERT "%s" TORTURE_FLAG + "rcu_torture_onoff task: " + "onlined %d\n", + torture_type, cpu); + n_online_successes++; + } + } + schedule_timeout_interruptible(onoff_interval * HZ); + } + VERBOSE_PRINTK_STRING("rcu_torture_onoff task stopping"); + return 0; +} + +static int +rcu_torture_onoff_init(void) +{ + if (onoff_interval <= 0) + return 0; + onoff_task = kthread_run(rcu_torture_onoff, NULL, "rcu_torture_onoff"); + if (IS_ERR(onoff_task)) { + onoff_task = NULL; + return PTR_ERR(onoff_task); + } + return 0; +} + +static void rcu_torture_onoff_cleanup(void) +{ + if (onoff_task == NULL) + return; + VERBOSE_PRINTK_STRING("Stopping rcu_torture_onoff task"); + kthread_stop(onoff_task); +} + +#else /* #ifdef CONFIG_HOTPLUG_CPU */ + +static void +rcu_torture_onoff_init(void) +{ +} + +static void rcu_torture_onoff_cleanup(void) +{ +} + +#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */ + static int rcutorture_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) { @@ -1391,6 +1585,11 @@ rcu_torture_cleanup(void) for_each_possible_cpu(i) rcutorture_booster_cleanup(i); } + if (shutdown_task != NULL) { + VERBOSE_PRINTK_STRING("Stopping rcu_torture_shutdown task"); + kthread_stop(shutdown_task); + } + rcu_torture_onoff_cleanup(); /* Wait for all RCU callbacks to fire. */ @@ -1416,7 +1615,7 @@ rcu_torture_init(void) static struct rcu_torture_ops *torture_ops[] = { &rcu_ops, &rcu_sync_ops, &rcu_expedited_ops, &rcu_bh_ops, &rcu_bh_sync_ops, &rcu_bh_expedited_ops, - &srcu_ops, &srcu_expedited_ops, + &srcu_ops, &srcu_raw_ops, &srcu_expedited_ops, &sched_ops, &sched_sync_ops, &sched_expedited_ops, }; mutex_lock(&fullstop_mutex); @@ -1607,6 +1806,18 @@ rcu_torture_init(void) } } } + if (shutdown_secs > 0) { + shutdown_time = jiffies + shutdown_secs * HZ; + shutdown_task = kthread_run(rcu_torture_shutdown, NULL, + "rcu_torture_shutdown"); + if (IS_ERR(shutdown_task)) { + firsterr = PTR_ERR(shutdown_task); + VERBOSE_PRINTK_ERRSTRING("Failed to create shutdown"); + shutdown_task = NULL; + goto unwind; + } + } + rcu_torture_onoff_init(); register_reboot_notifier(&rcutorture_shutdown_nb); rcutorture_record_test_transition(); mutex_unlock(&fullstop_mutex); diff --git a/kernel/rcutree.c b/kernel/rcutree.c index 6b76d81..6c4a672 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -69,7 +69,7 @@ static struct lock_class_key rcu_node_class[NUM_RCU_LVLS]; NUM_RCU_LVL_3, \ NUM_RCU_LVL_4, /* == MAX_RCU_LVLS */ \ }, \ - .signaled = RCU_GP_IDLE, \ + .fqs_state = RCU_GP_IDLE, \ .gpnum = -300, \ .completed = -300, \ .onofflock = __RAW_SPIN_LOCK_UNLOCKED(&structname##_state.onofflock), \ @@ -195,12 +195,10 @@ void rcu_note_context_switch(int cpu) } EXPORT_SYMBOL_GPL(rcu_note_context_switch); -#ifdef CONFIG_NO_HZ DEFINE_PER_CPU(struct rcu_dynticks, rcu_dynticks) = { - .dynticks_nesting = 1, + .dynticks_nesting = DYNTICK_TASK_NESTING, .dynticks = ATOMIC_INIT(1), }; -#endif /* #ifdef CONFIG_NO_HZ */ static int blimit = 10; /* Maximum callbacks per rcu_do_batch. */ static int qhimark = 10000; /* If this many pending, ignore blimit. */ @@ -328,11 +326,11 @@ static int rcu_implicit_offline_qs(struct rcu_data *rdp) return 1; } - /* If preemptible RCU, no point in sending reschedule IPI. */ - if (rdp->preemptible) - return 0; - - /* The CPU is online, so send it a reschedule IPI. */ + /* + * The CPU is online, so send it a reschedule IPI. This forces + * it through the scheduler, and (inefficiently) also handles cases + * where idle loops fail to inform RCU about the CPU being idle. + */ if (rdp->cpu != smp_processor_id()) smp_send_reschedule(rdp->cpu); else @@ -343,59 +341,181 @@ static int rcu_implicit_offline_qs(struct rcu_data *rdp) #endif /* #ifdef CONFIG_SMP */ -#ifdef CONFIG_NO_HZ +/* + * rcu_idle_enter_common - inform RCU that current CPU is moving towards idle + * + * If the new value of the ->dynticks_nesting counter now is zero, + * we really have entered idle, and must do the appropriate accounting. + * The caller must have disabled interrupts. + */ +static void rcu_idle_enter_common(struct rcu_dynticks *rdtp, long long oldval) +{ + trace_rcu_dyntick("Start", oldval, 0); + if (!is_idle_task(current)) { + struct task_struct *idle = idle_task(smp_processor_id()); + + trace_rcu_dyntick("Error on entry: not idle task", oldval, 0); + ftrace_dump(DUMP_ALL); + WARN_ONCE(1, "Current pid: %d comm: %s / Idle pid: %d comm: %s", + current->pid, current->comm, + idle->pid, idle->comm); /* must be idle task! */ + } + rcu_prepare_for_idle(smp_processor_id()); + /* CPUs seeing atomic_inc() must see prior RCU read-side crit sects */ + smp_mb__before_atomic_inc(); /* See above. */ + atomic_inc(&rdtp->dynticks); + smp_mb__after_atomic_inc(); /* Force ordering with next sojourn. */ + WARN_ON_ONCE(atomic_read(&rdtp->dynticks) & 0x1); +} /** - * rcu_enter_nohz - inform RCU that current CPU is entering nohz + * rcu_idle_enter - inform RCU that current CPU is entering idle * - * Enter nohz mode, in other words, -leave- the mode in which RCU + * Enter idle mode, in other words, -leave- the mode in which RCU * read-side critical sections can occur. (Though RCU read-side - * critical sections can occur in irq handlers in nohz mode, a possibility - * handled by rcu_irq_enter() and rcu_irq_exit()). + * critical sections can occur in irq handlers in idle, a possibility + * handled by irq_enter() and irq_exit().) + * + * We crowbar the ->dynticks_nesting field to zero to allow for + * the possibility of usermode upcalls having messed up our count + * of interrupt nesting level during the prior busy period. */ -void rcu_enter_nohz(void) +void rcu_idle_enter(void) { unsigned long flags; + long long oldval; struct rcu_dynticks *rdtp; local_irq_save(flags); rdtp = &__get_cpu_var(rcu_dynticks); - if (--rdtp->dynticks_nesting) { - local_irq_restore(flags); - return; - } - trace_rcu_dyntick("Start"); - /* CPUs seeing atomic_inc() must see prior RCU read-side crit sects */ - smp_mb__before_atomic_inc(); /* See above. */ - atomic_inc(&rdtp->dynticks); - smp_mb__after_atomic_inc(); /* Force ordering with next sojourn. */ - WARN_ON_ONCE(atomic_read(&rdtp->dynticks) & 0x1); + oldval = rdtp->dynticks_nesting; + rdtp->dynticks_nesting = 0; + rcu_idle_enter_common(rdtp, oldval); local_irq_restore(flags); } -/* - * rcu_exit_nohz - inform RCU that current CPU is leaving nohz +/** + * rcu_irq_exit - inform RCU that current CPU is exiting irq towards idle + * + * Exit from an interrupt handler, which might possibly result in entering + * idle mode, in other words, leaving the mode in which read-side critical + * sections can occur. * - * Exit nohz mode, in other words, -enter- the mode in which RCU - * read-side critical sections normally occur. + * This code assumes that the idle loop never does anything that might + * result in unbalanced calls to irq_enter() and irq_exit(). If your + * architecture violates this assumption, RCU will give you what you + * deserve, good and hard. But very infrequently and irreproducibly. + * + * Use things like work queues to work around this limitation. + * + * You have been warned. */ -void rcu_exit_nohz(void) +void rcu_irq_exit(void) { unsigned long flags; + long long oldval; struct rcu_dynticks *rdtp; local_irq_save(flags); rdtp = &__get_cpu_var(rcu_dynticks); - if (rdtp->dynticks_nesting++) { - local_irq_restore(flags); - return; - } + oldval = rdtp->dynticks_nesting; + rdtp->dynticks_nesting--; + WARN_ON_ONCE(rdtp->dynticks_nesting < 0); + if (rdtp->dynticks_nesting) + trace_rcu_dyntick("--=", oldval, rdtp->dynticks_nesting); + else + rcu_idle_enter_common(rdtp, oldval); + local_irq_restore(flags); +} + +/* + * rcu_idle_exit_common - inform RCU that current CPU is moving away from idle + * + * If the new value of the ->dynticks_nesting counter was previously zero, + * we really have exited idle, and must do the appropriate accounting. + * The caller must have disabled interrupts. + */ +static void rcu_idle_exit_common(struct rcu_dynticks *rdtp, long long oldval) +{ smp_mb__before_atomic_inc(); /* Force ordering w/previous sojourn. */ atomic_inc(&rdtp->dynticks); /* CPUs seeing atomic_inc() must see later RCU read-side crit sects */ smp_mb__after_atomic_inc(); /* See above. */ WARN_ON_ONCE(!(atomic_read(&rdtp->dynticks) & 0x1)); - trace_rcu_dyntick("End"); + rcu_cleanup_after_idle(smp_processor_id()); + trace_rcu_dyntick("End", oldval, rdtp->dynticks_nesting); + if (!is_idle_task(current)) { + struct task_struct *idle = idle_task(smp_processor_id()); + + trace_rcu_dyntick("Error on exit: not idle task", + oldval, rdtp->dynticks_nesting); + ftrace_dump(DUMP_ALL); + WARN_ONCE(1, "Current pid: %d comm: %s / Idle pid: %d comm: %s", + current->pid, current->comm, + idle->pid, idle->comm); /* must be idle task! */ + } +} + +/** + * rcu_idle_exit - inform RCU that current CPU is leaving idle + * + * Exit idle mode, in other words, -enter- the mode in which RCU + * read-side critical sections can occur. + * + * We crowbar the ->dynticks_nesting field to DYNTICK_TASK_NESTING to + * allow for the possibility of usermode upcalls messing up our count + * of interrupt nesting level during the busy period that is just + * now starting. + */ +void rcu_idle_exit(void) +{ + unsigned long flags; + struct rcu_dynticks *rdtp; + long long oldval; + + local_irq_save(flags); + rdtp = &__get_cpu_var(rcu_dynticks); + oldval = rdtp->dynticks_nesting; + WARN_ON_ONCE(oldval != 0); + rdtp->dynticks_nesting = DYNTICK_TASK_NESTING; + rcu_idle_exit_common(rdtp, oldval); + local_irq_restore(flags); +} + +/** + * rcu_irq_enter - inform RCU that current CPU is entering irq away from idle + * + * Enter an interrupt handler, which might possibly result in exiting + * idle mode, in other words, entering the mode in which read-side critical + * sections can occur. + * + * Note that the Linux kernel is fully capable of entering an interrupt + * handler that it never exits, for example when doing upcalls to + * user mode! This code assumes that the idle loop never does upcalls to + * user mode. If your architecture does do upcalls from the idle loop (or + * does anything else that results in unbalanced calls to the irq_enter() + * and irq_exit() functions), RCU will give you what you deserve, good + * and hard. But very infrequently and irreproducibly. + * + * Use things like work queues to work around this limitation. + * + * You have been warned. + */ +void rcu_irq_enter(void) +{ + unsigned long flags; + struct rcu_dynticks *rdtp; + long long oldval; + + local_irq_save(flags); + rdtp = &__get_cpu_var(rcu_dynticks); + oldval = rdtp->dynticks_nesting; + rdtp->dynticks_nesting++; + WARN_ON_ONCE(rdtp->dynticks_nesting == 0); + if (oldval) + trace_rcu_dyntick("++=", oldval, rdtp->dynticks_nesting); + else + rcu_idle_exit_common(rdtp, oldval); local_irq_restore(flags); } @@ -442,27 +562,37 @@ void rcu_nmi_exit(void) WARN_ON_ONCE(atomic_read(&rdtp->dynticks) & 0x1); } +#ifdef CONFIG_PROVE_RCU + /** - * rcu_irq_enter - inform RCU of entry to hard irq context + * rcu_is_cpu_idle - see if RCU thinks that the current CPU is idle * - * If the CPU was idle with dynamic ticks active, this updates the - * rdtp->dynticks to let the RCU handling know that the CPU is active. + * If the current CPU is in its idle loop and is neither in an interrupt + * or NMI handler, return true. */ -void rcu_irq_enter(void) +int rcu_is_cpu_idle(void) { - rcu_exit_nohz(); + int ret; + + preempt_disable(); + ret = (atomic_read(&__get_cpu_var(rcu_dynticks).dynticks) & 0x1) == 0; + preempt_enable(); + return ret; } +EXPORT_SYMBOL(rcu_is_cpu_idle); + +#endif /* #ifdef CONFIG_PROVE_RCU */ /** - * rcu_irq_exit - inform RCU of exit from hard irq context + * rcu_is_cpu_rrupt_from_idle - see if idle or immediately interrupted from idle * - * If the CPU was idle with dynamic ticks active, update the rdp->dynticks - * to put let the RCU handling be aware that the CPU is going back to idle - * with no ticks. + * If the current CPU is idle or running at a first-level (not nested) + * interrupt from idle, return true. The caller must have at least + * disabled preemption. */ -void rcu_irq_exit(void) +int rcu_is_cpu_rrupt_from_idle(void) { - rcu_enter_nohz(); + return __get_cpu_var(rcu_dynticks).dynticks_nesting <= 1; } #ifdef CONFIG_SMP @@ -475,7 +605,7 @@ void rcu_irq_exit(void) static int dyntick_save_progress_counter(struct rcu_data *rdp) { rdp->dynticks_snap = atomic_add_return(0, &rdp->dynticks->dynticks); - return 0; + return (rdp->dynticks_snap & 0x1) == 0; } /* @@ -512,26 +642,6 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp) #endif /* #ifdef CONFIG_SMP */ -#else /* #ifdef CONFIG_NO_HZ */ - -#ifdef CONFIG_SMP - -static int dyntick_save_progress_counter(struct rcu_data *rdp) -{ - return 0; -} - -static int rcu_implicit_dynticks_qs(struct rcu_data *rdp) -{ - return rcu_implicit_offline_qs(rdp); -} - -#endif /* #ifdef CONFIG_SMP */ - -#endif /* #else #ifdef CONFIG_NO_HZ */ - -int rcu_cpu_stall_suppress __read_mostly; - static void record_gp_stall_check_time(struct rcu_state *rsp) { rsp->gp_start = jiffies; @@ -866,8 +976,8 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags) /* Advance to a new grace period and initialize state. */ rsp->gpnum++; trace_rcu_grace_period(rsp->name, rsp->gpnum, "start"); - WARN_ON_ONCE(rsp->signaled == RCU_GP_INIT); - rsp->signaled = RCU_GP_INIT; /* Hold off force_quiescent_state. */ + WARN_ON_ONCE(rsp->fqs_state == RCU_GP_INIT); + rsp->fqs_state = RCU_GP_INIT; /* Hold off force_quiescent_state. */ rsp->jiffies_force_qs = jiffies + RCU_JIFFIES_TILL_FORCE_QS; record_gp_stall_check_time(rsp); @@ -877,7 +987,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags) rnp->qsmask = rnp->qsmaskinit; rnp->gpnum = rsp->gpnum; rnp->completed = rsp->completed; - rsp->signaled = RCU_SIGNAL_INIT; /* force_quiescent_state OK. */ + rsp->fqs_state = RCU_SIGNAL_INIT; /* force_quiescent_state OK */ rcu_start_gp_per_cpu(rsp, rnp, rdp); rcu_preempt_boost_start_gp(rnp); trace_rcu_grace_period_init(rsp->name, rnp->gpnum, @@ -927,7 +1037,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags) rnp = rcu_get_root(rsp); raw_spin_lock(&rnp->lock); /* irqs already disabled. */ - rsp->signaled = RCU_SIGNAL_INIT; /* force_quiescent_state now OK. */ + rsp->fqs_state = RCU_SIGNAL_INIT; /* force_quiescent_state now OK. */ raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ raw_spin_unlock_irqrestore(&rsp->onofflock, flags); } @@ -991,7 +1101,7 @@ static void rcu_report_qs_rsp(struct rcu_state *rsp, unsigned long flags) rsp->completed = rsp->gpnum; /* Declare the grace period complete. */ trace_rcu_grace_period(rsp->name, rsp->completed, "end"); - rsp->signaled = RCU_GP_IDLE; + rsp->fqs_state = RCU_GP_IDLE; rcu_start_gp(rsp, flags); /* releases root node's rnp->lock. */ } @@ -1221,7 +1331,7 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp) else raw_spin_unlock_irqrestore(&rnp->lock, flags); if (need_report & RCU_OFL_TASKS_EXP_GP) - rcu_report_exp_rnp(rsp, rnp); + rcu_report_exp_rnp(rsp, rnp, true); rcu_node_kthread_setaffinity(rnp, -1); } @@ -1263,7 +1373,9 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp) /* If no callbacks are ready, just return.*/ if (!cpu_has_callbacks_ready_to_invoke(rdp)) { trace_rcu_batch_start(rsp->name, 0, 0); - trace_rcu_batch_end(rsp->name, 0); + trace_rcu_batch_end(rsp->name, 0, !!ACCESS_ONCE(rdp->nxtlist), + need_resched(), is_idle_task(current), + rcu_is_callbacks_kthread()); return; } @@ -1291,12 +1403,17 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp) debug_rcu_head_unqueue(list); __rcu_reclaim(rsp->name, list); list = next; - if (++count >= bl) + /* Stop only if limit reached and CPU has something to do. */ + if (++count >= bl && + (need_resched() || + (!is_idle_task(current) && !rcu_is_callbacks_kthread()))) break; } local_irq_save(flags); - trace_rcu_batch_end(rsp->name, count); + trace_rcu_batch_end(rsp->name, count, !!list, need_resched(), + is_idle_task(current), + rcu_is_callbacks_kthread()); /* Update count, and requeue any remaining callbacks. */ rdp->qlen -= count; @@ -1334,16 +1451,14 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp) * (user mode or idle loop for rcu, non-softirq execution for rcu_bh). * Also schedule RCU core processing. * - * This function must be called with hardirqs disabled. It is normally + * This function must be called from hardirq context. It is normally * invoked from the scheduling-clock interrupt. If rcu_pending returns * false, there is no point in invoking rcu_check_callbacks(). */ void rcu_check_callbacks(int cpu, int user) { trace_rcu_utilization("Start scheduler-tick"); - if (user || - (idle_cpu(cpu) && rcu_scheduler_active && - !in_softirq() && hardirq_count() <= (1 << HARDIRQ_SHIFT))) { + if (user || rcu_is_cpu_rrupt_from_idle()) { /* * Get here if this CPU took its interrupt from user @@ -1457,7 +1572,7 @@ static void force_quiescent_state(struct rcu_state *rsp, int relaxed) goto unlock_fqs_ret; /* no GP in progress, time updated. */ } rsp->fqs_active = 1; - switch (rsp->signaled) { + switch (rsp->fqs_state) { case RCU_GP_IDLE: case RCU_GP_INIT: @@ -1473,7 +1588,7 @@ static void force_quiescent_state(struct rcu_state *rsp, int relaxed) force_qs_rnp(rsp, dyntick_save_progress_counter); raw_spin_lock(&rnp->lock); /* irqs already disabled */ if (rcu_gp_in_progress(rsp)) - rsp->signaled = RCU_FORCE_QS; + rsp->fqs_state = RCU_FORCE_QS; break; case RCU_FORCE_QS: @@ -1812,7 +1927,7 @@ static int rcu_pending(int cpu) * by the current CPU, even if none need be done immediately, returning * 1 if so. */ -static int rcu_needs_cpu_quick_check(int cpu) +static int rcu_cpu_has_callbacks(int cpu) { /* RCU callbacks either ready or pending? */ return per_cpu(rcu_sched_data, cpu).nxtlist || @@ -1913,9 +2028,9 @@ rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp) 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 */ + WARN_ON_ONCE(rdp->dynticks->dynticks_nesting != DYNTICK_TASK_NESTING); + WARN_ON_ONCE(atomic_read(&rdp->dynticks->dynticks) != 1); rdp->cpu = cpu; rdp->rsp = rsp; raw_spin_unlock_irqrestore(&rnp->lock, flags); @@ -1942,6 +2057,10 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptible) rdp->qlen_last_fqs_check = 0; rdp->n_force_qs_snap = rsp->n_force_qs; rdp->blimit = blimit; + rdp->dynticks->dynticks_nesting = DYNTICK_TASK_NESTING; + atomic_set(&rdp->dynticks->dynticks, + (atomic_read(&rdp->dynticks->dynticks) & ~0x1) + 1); + rcu_prepare_for_idle_init(cpu); raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ /* @@ -2023,6 +2142,7 @@ static int __cpuinit rcu_cpu_notify(struct notifier_block *self, rcu_send_cbs_to_online(&rcu_bh_state); rcu_send_cbs_to_online(&rcu_sched_state); rcu_preempt_send_cbs_to_online(); + rcu_cleanup_after_idle(cpu); break; case CPU_DEAD: case CPU_DEAD_FROZEN: diff --git a/kernel/rcutree.h b/kernel/rcutree.h index 849ce9e..fddff92 100644 --- a/kernel/rcutree.h +++ b/kernel/rcutree.h @@ -84,9 +84,10 @@ * Dynticks per-CPU state. */ struct rcu_dynticks { - int dynticks_nesting; /* Track irq/process nesting level. */ - int dynticks_nmi_nesting; /* Track NMI nesting level. */ - atomic_t dynticks; /* Even value for dynticks-idle, else odd. */ + long long dynticks_nesting; /* Track irq/process nesting level. */ + /* Process level is worth LLONG_MAX/2. */ + int dynticks_nmi_nesting; /* Track NMI nesting level. */ + atomic_t dynticks; /* Even value for idle, else odd. */ }; /* RCU's kthread states for tracing. */ @@ -274,16 +275,12 @@ struct rcu_data { /* did other CPU force QS recently? */ 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. */ -#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. */ @@ -302,16 +299,12 @@ struct rcu_data { struct rcu_state *rsp; }; -/* Values for signaled field in struct rcu_state. */ +/* Values for fqs_state field in struct rcu_state. */ #define RCU_GP_IDLE 0 /* No grace period in progress. */ #define RCU_GP_INIT 1 /* Grace period being initialized. */ #define RCU_SAVE_DYNTICK 2 /* Need to scan dyntick state. */ #define RCU_FORCE_QS 3 /* 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 */ @@ -361,7 +354,7 @@ struct rcu_state { /* The following fields are guarded by the root rcu_node's lock. */ - u8 signaled ____cacheline_internodealigned_in_smp; + u8 fqs_state ____cacheline_internodealigned_in_smp; /* Force QS state. */ u8 fqs_active; /* force_quiescent_state() */ /* is running. */ @@ -451,7 +444,8 @@ static void rcu_preempt_check_callbacks(int cpu); static void rcu_preempt_process_callbacks(void); void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu)); #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_TREE_PREEMPT_RCU) -static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp); +static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, + bool wake); #endif /* #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_TREE_PREEMPT_RCU) */ static int rcu_preempt_pending(int cpu); static int rcu_preempt_needs_cpu(int cpu); @@ -461,6 +455,7 @@ static void __init __rcu_init_preempt(void); static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags); static void rcu_preempt_boost_start_gp(struct rcu_node *rnp); static void invoke_rcu_callbacks_kthread(void); +static bool rcu_is_callbacks_kthread(void); #ifdef CONFIG_RCU_BOOST static void rcu_preempt_do_callbacks(void); static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, @@ -473,5 +468,8 @@ static void rcu_yield(void (*f)(unsigned long), unsigned long arg); #endif /* #ifdef CONFIG_RCU_BOOST */ static void rcu_cpu_kthread_setrt(int cpu, int to_rt); static void __cpuinit rcu_prepare_kthreads(int cpu); +static void rcu_prepare_for_idle_init(int cpu); +static void rcu_cleanup_after_idle(int cpu); +static void rcu_prepare_for_idle(int cpu); #endif /* #ifndef RCU_TREE_NONCORE */ diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 4b9b9f8..8bb35d7 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -312,6 +312,7 @@ static noinline void rcu_read_unlock_special(struct task_struct *t) { int empty; int empty_exp; + int empty_exp_now; unsigned long flags; struct list_head *np; #ifdef CONFIG_RCU_BOOST @@ -382,8 +383,10 @@ static noinline void rcu_read_unlock_special(struct task_struct *t) /* * 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 rcu_report_unblock_qs_rnp() releases rnp->lock. + * Note that rcu_report_unblock_qs_rnp() releases rnp->lock, + * so we must take a snapshot of the expedited state. */ + empty_exp_now = !rcu_preempted_readers_exp(rnp); if (!empty && !rcu_preempt_blocked_readers_cgp(rnp)) { trace_rcu_quiescent_state_report("preempt_rcu", rnp->gpnum, @@ -406,8 +409,8 @@ static noinline void rcu_read_unlock_special(struct task_struct *t) * If this was the last task on the expedited lists, * then we need to report up the rcu_node hierarchy. */ - if (!empty_exp && !rcu_preempted_readers_exp(rnp)) - rcu_report_exp_rnp(&rcu_preempt_state, rnp); + if (!empty_exp && empty_exp_now) + rcu_report_exp_rnp(&rcu_preempt_state, rnp, true); } else { local_irq_restore(flags); } @@ -729,9 +732,13 @@ static int sync_rcu_preempt_exp_done(struct rcu_node *rnp) * recursively up the tree. (Calm down, calm down, we do the recursion * iteratively!) * + * Most callers will set the "wake" flag, but the task initiating the + * expedited grace period need not wake itself. + * * Caller must hold sync_rcu_preempt_exp_mutex. */ -static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp) +static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, + bool wake) { unsigned long flags; unsigned long mask; @@ -744,7 +751,8 @@ static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp) } if (rnp->parent == NULL) { raw_spin_unlock_irqrestore(&rnp->lock, flags); - wake_up(&sync_rcu_preempt_exp_wq); + if (wake) + wake_up(&sync_rcu_preempt_exp_wq); break; } mask = rnp->grpmask; @@ -777,7 +785,7 @@ sync_rcu_preempt_exp_init(struct rcu_state *rsp, struct rcu_node *rnp) must_wait = 1; } if (!must_wait) - rcu_report_exp_rnp(rsp, rnp); + rcu_report_exp_rnp(rsp, rnp, false); /* Don't wake self. */ } /* @@ -1069,9 +1077,9 @@ EXPORT_SYMBOL_GPL(synchronize_rcu_expedited); * report on tasks preempted in RCU read-side critical sections during * expedited RCU grace periods. */ -static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp) +static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, + bool wake) { - return; } #endif /* #ifdef CONFIG_HOTPLUG_CPU */ @@ -1157,8 +1165,6 @@ static void rcu_initiate_boost_trace(struct rcu_node *rnp) #endif /* #else #ifdef CONFIG_RCU_TRACE */ -static struct lock_class_key rcu_boost_class; - /* * Carry out RCU priority boosting on the task indicated by ->exp_tasks * or ->boost_tasks, advancing the pointer to the next task in the @@ -1221,15 +1227,13 @@ static int rcu_boost(struct rcu_node *rnp) */ t = container_of(tb, struct task_struct, rcu_node_entry); rt_mutex_init_proxy_locked(&mtx, t); - /* Avoid lockdep false positives. This rt_mutex is its own thing. */ - lockdep_set_class_and_name(&mtx.wait_lock, &rcu_boost_class, - "rcu_boost_mutex"); t->rcu_boost_mutex = &mtx; raw_spin_unlock_irqrestore(&rnp->lock, flags); rt_mutex_lock(&mtx); /* Side effect: boosts task t's priority. */ rt_mutex_unlock(&mtx); /* Keep lockdep happy. */ - return rnp->exp_tasks != NULL || rnp->boost_tasks != NULL; + return ACCESS_ONCE(rnp->exp_tasks) != NULL || + ACCESS_ONCE(rnp->boost_tasks) != NULL; } /* @@ -1329,6 +1333,15 @@ static void invoke_rcu_callbacks_kthread(void) } /* + * Is the current CPU running the RCU-callbacks kthread? + * Caller must have preemption disabled. + */ +static bool rcu_is_callbacks_kthread(void) +{ + return __get_cpu_var(rcu_cpu_kthread_task) == current; +} + +/* * Set the affinity of the boost kthread. The CPU-hotplug locks are * held, so no one should be messing with the existence of the boost * kthread. @@ -1772,6 +1785,11 @@ static void invoke_rcu_callbacks_kthread(void) WARN_ON_ONCE(1); } +static bool rcu_is_callbacks_kthread(void) +{ + return false; +} + static void rcu_preempt_boost_start_gp(struct rcu_node *rnp) { } @@ -1907,7 +1925,7 @@ void synchronize_sched_expedited(void) * grace period works for us. */ get_online_cpus(); - snap = atomic_read(&sync_sched_expedited_started) - 1; + snap = atomic_read(&sync_sched_expedited_started); smp_mb(); /* ensure read is before try_stop_cpus(). */ } @@ -1939,88 +1957,243 @@ EXPORT_SYMBOL_GPL(synchronize_sched_expedited); * 1 if so. This function is part of the RCU implementation; it is -not- * an exported member of the RCU API. * - * Because we have preemptible RCU, just check whether this CPU needs - * any flavor of RCU. Do not chew up lots of CPU cycles with preemption - * disabled in a most-likely vain attempt to cause RCU not to need this CPU. + * Because we not have RCU_FAST_NO_HZ, just check whether this CPU needs + * any flavor of RCU. */ int rcu_needs_cpu(int cpu) { - return rcu_needs_cpu_quick_check(cpu); + return rcu_cpu_has_callbacks(cpu); +} + +/* + * Because we do not have RCU_FAST_NO_HZ, don't bother initializing for it. + */ +static void rcu_prepare_for_idle_init(int cpu) +{ +} + +/* + * Because we do not have RCU_FAST_NO_HZ, don't bother cleaning up + * after it. + */ +static void rcu_cleanup_after_idle(int cpu) +{ +} + +/* + * Do the idle-entry grace-period work, which, because CONFIG_RCU_FAST_NO_HZ=y, + * is nothing. + */ +static void rcu_prepare_for_idle(int cpu) +{ } #else /* #if !defined(CONFIG_RCU_FAST_NO_HZ) */ -#define RCU_NEEDS_CPU_FLUSHES 5 +/* + * This code is invoked when a CPU goes idle, at which point we want + * to have the CPU do everything required for RCU so that it can enter + * the energy-efficient dyntick-idle mode. This is handled by a + * state machine implemented by rcu_prepare_for_idle() below. + * + * The following three proprocessor symbols control this state machine: + * + * RCU_IDLE_FLUSHES gives the maximum number of times that we will attempt + * to satisfy RCU. Beyond this point, it is better to incur a periodic + * scheduling-clock interrupt than to loop through the state machine + * at full power. + * RCU_IDLE_OPT_FLUSHES gives the number of RCU_IDLE_FLUSHES that are + * optional if RCU does not need anything immediately from this + * CPU, even if this CPU still has RCU callbacks queued. The first + * times through the state machine are mandatory: we need to give + * the state machine a chance to communicate a quiescent state + * to the RCU core. + * RCU_IDLE_GP_DELAY gives the number of jiffies that a CPU is permitted + * to sleep in dyntick-idle mode with RCU callbacks pending. This + * is sized to be roughly one RCU grace period. Those energy-efficiency + * benchmarkers who might otherwise be tempted to set this to a large + * number, be warned: Setting RCU_IDLE_GP_DELAY too high can hang your + * system. And if you are -that- concerned about energy efficiency, + * just power the system down and be done with it! + * + * The values below work well in practice. If future workloads require + * adjustment, they can be converted into kernel config parameters, though + * making the state machine smarter might be a better option. + */ +#define RCU_IDLE_FLUSHES 5 /* Number of dyntick-idle tries. */ +#define RCU_IDLE_OPT_FLUSHES 3 /* Optional dyntick-idle tries. */ +#define RCU_IDLE_GP_DELAY 6 /* Roughly one grace period. */ + static DEFINE_PER_CPU(int, rcu_dyntick_drain); static DEFINE_PER_CPU(unsigned long, rcu_dyntick_holdoff); +static DEFINE_PER_CPU(struct hrtimer, rcu_idle_gp_timer); +static ktime_t rcu_idle_gp_wait; /* - * 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. + * Allow the CPU to enter dyntick-idle mode if either: (1) There are no + * callbacks on this CPU, (2) this CPU has not yet attempted to enter + * dyntick-idle mode, or (3) this CPU is in the process of attempting to + * enter dyntick-idle mode. Otherwise, if we have recently tried and failed + * to enter dyntick-idle mode, we refuse to try to enter it. After all, + * it is better to incur scheduling-clock interrupts than to spin + * continuously for the same time duration! + */ +int rcu_needs_cpu(int cpu) +{ + /* If no callbacks, RCU doesn't need the CPU. */ + if (!rcu_cpu_has_callbacks(cpu)) + return 0; + /* Otherwise, RCU needs the CPU only if it recently tried and failed. */ + return per_cpu(rcu_dyntick_holdoff, cpu) == jiffies; +} + +/* + * Timer handler used to force CPU to start pushing its remaining RCU + * callbacks in the case where it entered dyntick-idle mode with callbacks + * pending. The hander doesn't really need to do anything because the + * real work is done upon re-entry to idle, or by the next scheduling-clock + * interrupt should idle not be re-entered. + */ +static enum hrtimer_restart rcu_idle_gp_timer_func(struct hrtimer *hrtp) +{ + trace_rcu_prep_idle("Timer"); + return HRTIMER_NORESTART; +} + +/* + * Initialize the timer used to pull CPUs out of dyntick-idle mode. + */ +static void rcu_prepare_for_idle_init(int cpu) +{ + static int firsttime = 1; + struct hrtimer *hrtp = &per_cpu(rcu_idle_gp_timer, cpu); + + hrtimer_init(hrtp, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + hrtp->function = rcu_idle_gp_timer_func; + if (firsttime) { + unsigned int upj = jiffies_to_usecs(RCU_IDLE_GP_DELAY); + + rcu_idle_gp_wait = ns_to_ktime(upj * (u64)1000); + firsttime = 0; + } +} + +/* + * Clean up for exit from idle. Because we are exiting from idle, there + * is no longer any point to rcu_idle_gp_timer, so cancel it. This will + * do nothing if this timer is not active, so just cancel it unconditionally. + */ +static void rcu_cleanup_after_idle(int cpu) +{ + hrtimer_cancel(&per_cpu(rcu_idle_gp_timer, cpu)); +} + +/* + * Check to see if any RCU-related work can be done by the current CPU, + * and if so, schedule a softirq to get it done. This function is part + * of the RCU implementation; it is -not- an exported member of the RCU API. * - * Because we are not supporting preemptible RCU, attempt to accelerate - * any current grace periods so that RCU no longer needs this CPU, but - * only if all other CPUs are already in dynticks-idle mode. This will - * allow the CPU cores to be powered down immediately, as opposed to after - * waiting many milliseconds for grace periods to elapse. + * The idea is for the current CPU to clear out all work required by the + * RCU core for the current grace period, so that this CPU can be permitted + * to enter dyntick-idle mode. In some cases, it will need to be awakened + * at the end of the grace period by whatever CPU ends the grace period. + * This allows CPUs to go dyntick-idle more quickly, and to reduce the + * number of wakeups by a modest integer factor. * * Because it is not legal to invoke rcu_process_callbacks() with irqs * disabled, we do one pass of force_quiescent_state(), then do a * invoke_rcu_core() to cause rcu_process_callbacks() to be invoked * later. The per-cpu rcu_dyntick_drain variable controls the sequencing. + * + * The caller must have disabled interrupts. */ -int rcu_needs_cpu(int cpu) +static void rcu_prepare_for_idle(int cpu) { - int c = 0; - int snap; - int thatcpu; - - /* Check for being in the holdoff period. */ - if (per_cpu(rcu_dyntick_holdoff, cpu) == jiffies) - return rcu_needs_cpu_quick_check(cpu); - - /* Don't bother unless we are the last non-dyntick-idle CPU. */ - for_each_online_cpu(thatcpu) { - if (thatcpu == cpu) - continue; - snap = atomic_add_return(0, &per_cpu(rcu_dynticks, - thatcpu).dynticks); - smp_mb(); /* Order sampling of snap with end of grace period. */ - if ((snap & 0x1) != 0) { - per_cpu(rcu_dyntick_drain, cpu) = 0; - per_cpu(rcu_dyntick_holdoff, cpu) = jiffies - 1; - return rcu_needs_cpu_quick_check(cpu); - } + unsigned long flags; + + local_irq_save(flags); + + /* + * If there are no callbacks on this CPU, enter dyntick-idle mode. + * Also reset state to avoid prejudicing later attempts. + */ + if (!rcu_cpu_has_callbacks(cpu)) { + per_cpu(rcu_dyntick_holdoff, cpu) = jiffies - 1; + per_cpu(rcu_dyntick_drain, cpu) = 0; + local_irq_restore(flags); + trace_rcu_prep_idle("No callbacks"); + return; + } + + /* + * If in holdoff mode, just return. We will presumably have + * refrained from disabling the scheduling-clock tick. + */ + if (per_cpu(rcu_dyntick_holdoff, cpu) == jiffies) { + local_irq_restore(flags); + trace_rcu_prep_idle("In holdoff"); + return; } /* Check and update the rcu_dyntick_drain sequencing. */ if (per_cpu(rcu_dyntick_drain, cpu) <= 0) { /* First time through, initialize the counter. */ - per_cpu(rcu_dyntick_drain, cpu) = RCU_NEEDS_CPU_FLUSHES; + per_cpu(rcu_dyntick_drain, cpu) = RCU_IDLE_FLUSHES; + } else if (per_cpu(rcu_dyntick_drain, cpu) <= RCU_IDLE_OPT_FLUSHES && + !rcu_pending(cpu)) { + /* Can we go dyntick-idle despite still having callbacks? */ + trace_rcu_prep_idle("Dyntick with callbacks"); + per_cpu(rcu_dyntick_drain, cpu) = 0; + per_cpu(rcu_dyntick_holdoff, cpu) = jiffies - 1; + hrtimer_start(&per_cpu(rcu_idle_gp_timer, cpu), + rcu_idle_gp_wait, HRTIMER_MODE_REL); + return; /* Nothing more to do immediately. */ } else if (--per_cpu(rcu_dyntick_drain, cpu) <= 0) { /* We have hit the limit, so time to give up. */ per_cpu(rcu_dyntick_holdoff, cpu) = jiffies; - return rcu_needs_cpu_quick_check(cpu); + local_irq_restore(flags); + trace_rcu_prep_idle("Begin holdoff"); + invoke_rcu_core(); /* Force the CPU out of dyntick-idle. */ + return; } - /* Do one step pushing remaining RCU callbacks through. */ + /* + * Do one step of pushing the remaining RCU callbacks through + * the RCU core state machine. + */ +#ifdef CONFIG_TREE_PREEMPT_RCU + if (per_cpu(rcu_preempt_data, cpu).nxtlist) { + local_irq_restore(flags); + rcu_preempt_qs(cpu); + force_quiescent_state(&rcu_preempt_state, 0); + local_irq_save(flags); + } +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ if (per_cpu(rcu_sched_data, cpu).nxtlist) { + local_irq_restore(flags); rcu_sched_qs(cpu); force_quiescent_state(&rcu_sched_state, 0); - c = c || per_cpu(rcu_sched_data, cpu).nxtlist; + local_irq_save(flags); } if (per_cpu(rcu_bh_data, cpu).nxtlist) { + local_irq_restore(flags); rcu_bh_qs(cpu); force_quiescent_state(&rcu_bh_state, 0); - c = c || per_cpu(rcu_bh_data, cpu).nxtlist; + local_irq_save(flags); } - /* If RCU callbacks are still pending, RCU still needs this CPU. */ - if (c) + /* + * If RCU callbacks are still pending, RCU still needs this CPU. + * So try forcing the callbacks through the grace period. + */ + if (rcu_cpu_has_callbacks(cpu)) { + local_irq_restore(flags); + trace_rcu_prep_idle("More callbacks"); invoke_rcu_core(); - return c; + } else { + local_irq_restore(flags); + trace_rcu_prep_idle("Callbacks drained"); + } } #endif /* #else #if !defined(CONFIG_RCU_FAST_NO_HZ) */ diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c index 9feffa4..654cfe6 100644 --- a/kernel/rcutree_trace.c +++ b/kernel/rcutree_trace.c @@ -67,13 +67,11 @@ static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp) rdp->completed, rdp->gpnum, rdp->passed_quiesce, rdp->passed_quiesce_gpnum, rdp->qs_pending); -#ifdef CONFIG_NO_HZ - seq_printf(m, " dt=%d/%d/%d df=%lu", + seq_printf(m, " dt=%d/%llx/%d df=%lu", atomic_read(&rdp->dynticks->dynticks), rdp->dynticks->dynticks_nesting, rdp->dynticks->dynticks_nmi_nesting, rdp->dynticks_fqs); -#endif /* #ifdef CONFIG_NO_HZ */ seq_printf(m, " of=%lu ri=%lu", rdp->offline_fqs, rdp->resched_ipi); seq_printf(m, " ql=%ld qs=%c%c%c%c", rdp->qlen, @@ -141,13 +139,11 @@ static void print_one_rcu_data_csv(struct seq_file *m, struct rcu_data *rdp) rdp->completed, rdp->gpnum, rdp->passed_quiesce, rdp->passed_quiesce_gpnum, rdp->qs_pending); -#ifdef CONFIG_NO_HZ - seq_printf(m, ",%d,%d,%d,%lu", + seq_printf(m, ",%d,%llx,%d,%lu", atomic_read(&rdp->dynticks->dynticks), rdp->dynticks->dynticks_nesting, rdp->dynticks->dynticks_nmi_nesting, rdp->dynticks_fqs); -#endif /* #ifdef CONFIG_NO_HZ */ seq_printf(m, ",%lu,%lu", rdp->offline_fqs, rdp->resched_ipi); seq_printf(m, ",%ld,\"%c%c%c%c\"", rdp->qlen, ".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] != @@ -171,9 +167,7 @@ static void print_one_rcu_data_csv(struct seq_file *m, struct rcu_data *rdp) static int show_rcudata_csv(struct seq_file *m, void *unused) { seq_puts(m, "\"CPU\",\"Online?\",\"c\",\"g\",\"pq\",\"pgp\",\"pq\","); -#ifdef CONFIG_NO_HZ seq_puts(m, "\"dt\",\"dt nesting\",\"dt NMI nesting\",\"df\","); -#endif /* #ifdef CONFIG_NO_HZ */ seq_puts(m, "\"of\",\"ri\",\"ql\",\"qs\""); #ifdef CONFIG_RCU_BOOST seq_puts(m, "\"kt\",\"ktl\""); @@ -278,7 +272,7 @@ static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp) gpnum = rsp->gpnum; seq_printf(m, "c=%lu g=%lu s=%d jfq=%ld j=%x " "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu\n", - rsp->completed, gpnum, rsp->signaled, + rsp->completed, gpnum, rsp->fqs_state, (long)(rsp->jiffies_force_qs - jiffies), (int)(jiffies & 0xffff), rsp->n_force_qs, rsp->n_force_qs_ngp, diff --git a/kernel/relay.c b/kernel/relay.c index 226fade..4335e1d 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -302,7 +302,7 @@ static void buf_unmapped_default_callback(struct rchan_buf *buf, */ static struct dentry *create_buf_file_default_callback(const char *filename, struct dentry *parent, - int mode, + umode_t mode, struct rchan_buf *buf, int *is_global) { diff --git a/kernel/res_counter.c b/kernel/res_counter.c index 34683ef..6d269cc 100644 --- a/kernel/res_counter.c +++ b/kernel/res_counter.c @@ -159,8 +159,7 @@ int res_counter_memparse_write_strategy(const char *buf, return 0; } - /* FIXME - make memparse() take const char* args */ - *res = memparse((char *)buf, &end); + *res = memparse(buf, &end); if (*end != '\0') return -EINVAL; diff --git a/kernel/rtmutex-debug.c b/kernel/rtmutex-debug.c index 8eafd1b..16502d3 100644 --- a/kernel/rtmutex-debug.c +++ b/kernel/rtmutex-debug.c @@ -101,6 +101,7 @@ void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter) printk("\n============================================\n"); printk( "[ BUG: circular locking deadlock detected! ]\n"); + printk("%s\n", print_tainted()); printk( "--------------------------------------------\n"); printk("%s/%d is deadlocking current task %s/%d\n\n", task->comm, task_pid_nr(task), diff --git a/kernel/rtmutex-tester.c b/kernel/rtmutex-tester.c index 3d9f31c..98ec494 100644 --- a/kernel/rtmutex-tester.c +++ b/kernel/rtmutex-tester.c @@ -6,11 +6,11 @@ * Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com> * */ +#include <linux/device.h> #include <linux/kthread.h> #include <linux/export.h> #include <linux/sched.h> #include <linux/spinlock.h> -#include <linux/sysdev.h> #include <linux/timer.h> #include <linux/freezer.h> @@ -27,7 +27,7 @@ struct test_thread_data { int opdata; int mutexes[MAX_RT_TEST_MUTEXES]; int event; - struct sys_device sysdev; + struct device dev; }; static struct test_thread_data thread_data[MAX_RT_TEST_THREADS]; @@ -271,7 +271,7 @@ static int test_func(void *data) * * opcode:data */ -static ssize_t sysfs_test_command(struct sys_device *dev, struct sysdev_attribute *attr, +static ssize_t sysfs_test_command(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct sched_param schedpar; @@ -279,8 +279,8 @@ static ssize_t sysfs_test_command(struct sys_device *dev, struct sysdev_attribut char cmdbuf[32]; int op, dat, tid, ret; - td = container_of(dev, struct test_thread_data, sysdev); - tid = td->sysdev.id; + td = container_of(dev, struct test_thread_data, dev); + tid = td->dev.id; /* strings from sysfs write are not 0 terminated! */ if (count >= sizeof(cmdbuf)) @@ -334,7 +334,7 @@ static ssize_t sysfs_test_command(struct sys_device *dev, struct sysdev_attribut * @dev: thread to query * @buf: char buffer to be filled with thread status info */ -static ssize_t sysfs_test_status(struct sys_device *dev, struct sysdev_attribute *attr, +static ssize_t sysfs_test_status(struct device *dev, struct device_attribute *attr, char *buf) { struct test_thread_data *td; @@ -342,8 +342,8 @@ static ssize_t sysfs_test_status(struct sys_device *dev, struct sysdev_attribute char *curr = buf; int i; - td = container_of(dev, struct test_thread_data, sysdev); - tsk = threads[td->sysdev.id]; + td = container_of(dev, struct test_thread_data, dev); + tsk = threads[td->dev.id]; spin_lock(&rttest_lock); @@ -360,28 +360,29 @@ static ssize_t sysfs_test_status(struct sys_device *dev, struct sysdev_attribute spin_unlock(&rttest_lock); curr += sprintf(curr, ", T: %p, R: %p\n", tsk, - mutexes[td->sysdev.id].owner); + mutexes[td->dev.id].owner); return curr - buf; } -static SYSDEV_ATTR(status, 0600, sysfs_test_status, NULL); -static SYSDEV_ATTR(command, 0600, NULL, sysfs_test_command); +static DEVICE_ATTR(status, 0600, sysfs_test_status, NULL); +static DEVICE_ATTR(command, 0600, NULL, sysfs_test_command); -static struct sysdev_class rttest_sysclass = { +static struct bus_type rttest_subsys = { .name = "rttest", + .dev_name = "rttest", }; static int init_test_thread(int id) { - thread_data[id].sysdev.cls = &rttest_sysclass; - thread_data[id].sysdev.id = id; + thread_data[id].dev.bus = &rttest_subsys; + thread_data[id].dev.id = id; threads[id] = kthread_run(test_func, &thread_data[id], "rt-test-%d", id); if (IS_ERR(threads[id])) return PTR_ERR(threads[id]); - return sysdev_register(&thread_data[id].sysdev); + return device_register(&thread_data[id].dev); } static int init_rttest(void) @@ -393,7 +394,7 @@ static int init_rttest(void) for (i = 0; i < MAX_RT_TEST_MUTEXES; i++) rt_mutex_init(&mutexes[i]); - ret = sysdev_class_register(&rttest_sysclass); + ret = subsys_system_register(&rttest_subsys, NULL); if (ret) return ret; @@ -401,10 +402,10 @@ static int init_rttest(void) ret = init_test_thread(i); if (ret) break; - ret = sysdev_create_file(&thread_data[i].sysdev, &attr_status); + ret = device_create_file(&thread_data[i].dev, &dev_attr_status); if (ret) break; - ret = sysdev_create_file(&thread_data[i].sysdev, &attr_command); + ret = device_create_file(&thread_data[i].dev, &dev_attr_command); if (ret) break; } diff --git a/kernel/rtmutex.c b/kernel/rtmutex.c index f9d8482..a242e69 100644 --- a/kernel/rtmutex.c +++ b/kernel/rtmutex.c @@ -579,7 +579,6 @@ __rt_mutex_slowlock(struct rt_mutex *lock, int state, struct rt_mutex_waiter *waiter) { int ret = 0; - int was_disabled; for (;;) { /* Try to acquire the lock: */ @@ -602,17 +601,10 @@ __rt_mutex_slowlock(struct rt_mutex *lock, int state, raw_spin_unlock(&lock->wait_lock); - was_disabled = irqs_disabled(); - if (was_disabled) - local_irq_enable(); - debug_rt_mutex_print_deadlock(waiter); schedule_rt_mutex(lock); - if (was_disabled) - local_irq_disable(); - raw_spin_lock(&lock->wait_lock); set_current_state(state); } diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile new file mode 100644 index 0000000..9a7dd35 --- /dev/null +++ b/kernel/sched/Makefile @@ -0,0 +1,20 @@ +ifdef CONFIG_FUNCTION_TRACER +CFLAGS_REMOVE_clock.o = -pg +endif + +ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER),y) +# According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is +# needed for x86 only. Why this used to be enabled for all architectures is beyond +# me. I suspect most platforms don't need this, but until we know that for sure +# I turn this off for IA-64 only. Andreas Schwab says it's also needed on m68k +# to get a correct value for the wait-channel (WCHAN in ps). --davidm +CFLAGS_core.o := $(PROFILING) -fno-omit-frame-pointer +endif + +obj-y += core.o clock.o idle_task.o fair.o rt.o stop_task.o +obj-$(CONFIG_SMP) += cpupri.o +obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o +obj-$(CONFIG_SCHEDSTATS) += stats.o +obj-$(CONFIG_SCHED_DEBUG) += debug.o + + diff --git a/kernel/sched_autogroup.c b/kernel/sched/auto_group.c index 429242f..e8a1f83 100644 --- a/kernel/sched_autogroup.c +++ b/kernel/sched/auto_group.c @@ -1,15 +1,19 @@ #ifdef CONFIG_SCHED_AUTOGROUP +#include "sched.h" + #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/kallsyms.h> #include <linux/utsname.h> +#include <linux/security.h> +#include <linux/export.h> unsigned int __read_mostly sysctl_sched_autogroup_enabled = 1; static struct autogroup autogroup_default; static atomic_t autogroup_seq_nr; -static void __init autogroup_init(struct task_struct *init_task) +void __init autogroup_init(struct task_struct *init_task) { autogroup_default.tg = &root_task_group; kref_init(&autogroup_default.kref); @@ -17,7 +21,7 @@ static void __init autogroup_init(struct task_struct *init_task) init_task->signal->autogroup = &autogroup_default; } -static inline void autogroup_free(struct task_group *tg) +void autogroup_free(struct task_group *tg) { kfree(tg->autogroup); } @@ -59,10 +63,6 @@ static inline struct autogroup *autogroup_task_get(struct task_struct *p) return ag; } -#ifdef CONFIG_RT_GROUP_SCHED -static void free_rt_sched_group(struct task_group *tg); -#endif - static inline struct autogroup *autogroup_create(void) { struct autogroup *ag = kzalloc(sizeof(*ag), GFP_KERNEL); @@ -108,8 +108,7 @@ out_fail: return autogroup_kref_get(&autogroup_default); } -static inline bool -task_wants_autogroup(struct task_struct *p, struct task_group *tg) +bool task_wants_autogroup(struct task_struct *p, struct task_group *tg) { if (tg != &root_task_group) return false; @@ -127,22 +126,6 @@ task_wants_autogroup(struct task_struct *p, struct task_group *tg) return true; } -static inline bool task_group_is_autogroup(struct task_group *tg) -{ - return !!tg->autogroup; -} - -static inline struct task_group * -autogroup_task_group(struct task_struct *p, struct task_group *tg) -{ - int enabled = ACCESS_ONCE(sysctl_sched_autogroup_enabled); - - if (enabled && task_wants_autogroup(p, tg)) - return p->signal->autogroup->tg; - - return tg; -} - static void autogroup_move_group(struct task_struct *p, struct autogroup *ag) { @@ -263,7 +246,7 @@ out: #endif /* CONFIG_PROC_FS */ #ifdef CONFIG_SCHED_DEBUG -static inline int autogroup_path(struct task_group *tg, char *buf, int buflen) +int autogroup_path(struct task_group *tg, char *buf, int buflen) { if (!task_group_is_autogroup(tg)) return 0; diff --git a/kernel/sched_autogroup.h b/kernel/sched/auto_group.h index c2f0e72..8bd0471 100644 --- a/kernel/sched_autogroup.h +++ b/kernel/sched/auto_group.h @@ -1,5 +1,8 @@ #ifdef CONFIG_SCHED_AUTOGROUP +#include <linux/kref.h> +#include <linux/rwsem.h> + struct autogroup { /* * reference doesn't mean how many thread attach to this @@ -13,9 +16,28 @@ struct autogroup { int nice; }; -static inline bool task_group_is_autogroup(struct task_group *tg); +extern void autogroup_init(struct task_struct *init_task); +extern void autogroup_free(struct task_group *tg); + +static inline bool task_group_is_autogroup(struct task_group *tg) +{ + return !!tg->autogroup; +} + +extern bool task_wants_autogroup(struct task_struct *p, struct task_group *tg); + static inline struct task_group * -autogroup_task_group(struct task_struct *p, struct task_group *tg); +autogroup_task_group(struct task_struct *p, struct task_group *tg) +{ + int enabled = ACCESS_ONCE(sysctl_sched_autogroup_enabled); + + if (enabled && task_wants_autogroup(p, tg)) + return p->signal->autogroup->tg; + + return tg; +} + +extern int autogroup_path(struct task_group *tg, char *buf, int buflen); #else /* !CONFIG_SCHED_AUTOGROUP */ diff --git a/kernel/sched_clock.c b/kernel/sched/clock.c index c685e31..c685e31 100644 --- a/kernel/sched_clock.c +++ b/kernel/sched/clock.c diff --git a/kernel/sched.c b/kernel/sched/core.c index d6b149c..df00cb0 100644 --- a/kernel/sched.c +++ b/kernel/sched/core.c @@ -1,5 +1,5 @@ /* - * kernel/sched.c + * kernel/sched/core.c * * Kernel scheduler and related syscalls * @@ -56,7 +56,6 @@ #include <linux/percpu.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> -#include <linux/stop_machine.h> #include <linux/sysctl.h> #include <linux/syscalls.h> #include <linux/times.h> @@ -75,129 +74,17 @@ #include <asm/tlb.h> #include <asm/irq_regs.h> -#include <asm/mutex.h> #ifdef CONFIG_PARAVIRT #include <asm/paravirt.h> #endif -#include "sched_cpupri.h" -#include "workqueue_sched.h" -#include "sched_autogroup.h" +#include "sched.h" +#include "../workqueue_sched.h" #define CREATE_TRACE_POINTS #include <trace/events/sched.h> -/* - * Convert user-nice values [ -20 ... 0 ... 19 ] - * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ], - * and back. - */ -#define NICE_TO_PRIO(nice) (MAX_RT_PRIO + (nice) + 20) -#define PRIO_TO_NICE(prio) ((prio) - MAX_RT_PRIO - 20) -#define TASK_NICE(p) PRIO_TO_NICE((p)->static_prio) - -/* - * 'User priority' is the nice value converted to something we - * can work with better when scaling various scheduler parameters, - * it's a [ 0 ... 39 ] range. - */ -#define USER_PRIO(p) ((p)-MAX_RT_PRIO) -#define TASK_USER_PRIO(p) USER_PRIO((p)->static_prio) -#define MAX_USER_PRIO (USER_PRIO(MAX_PRIO)) - -/* - * Helpers for converting nanosecond timing to jiffy resolution - */ -#define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ)) - -#define NICE_0_LOAD SCHED_LOAD_SCALE -#define NICE_0_SHIFT SCHED_LOAD_SHIFT - -/* - * These are the 'tuning knobs' of the scheduler: - * - * default timeslice is 100 msecs (used only for SCHED_RR tasks). - * Timeslices get refilled after they expire. - */ -#define DEF_TIMESLICE (100 * HZ / 1000) - -/* - * single value that denotes runtime == period, ie unlimited time. - */ -#define RUNTIME_INF ((u64)~0ULL) - -static inline int rt_policy(int policy) -{ - if (policy == SCHED_FIFO || policy == SCHED_RR) - return 1; - return 0; -} - -static inline int task_has_rt_policy(struct task_struct *p) -{ - return rt_policy(p->policy); -} - -/* - * This is the priority-queue data structure of the RT scheduling class: - */ -struct rt_prio_array { - DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */ - struct list_head queue[MAX_RT_PRIO]; -}; - -struct rt_bandwidth { - /* nests inside the rq lock: */ - raw_spinlock_t rt_runtime_lock; - ktime_t rt_period; - u64 rt_runtime; - struct hrtimer rt_period_timer; -}; - -static struct rt_bandwidth def_rt_bandwidth; - -static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun); - -static enum hrtimer_restart sched_rt_period_timer(struct hrtimer *timer) -{ - struct rt_bandwidth *rt_b = - container_of(timer, struct rt_bandwidth, rt_period_timer); - ktime_t now; - int overrun; - int idle = 0; - - for (;;) { - now = hrtimer_cb_get_time(timer); - overrun = hrtimer_forward(timer, now, rt_b->rt_period); - - if (!overrun) - break; - - idle = do_sched_rt_period_timer(rt_b, overrun); - } - - return idle ? HRTIMER_NORESTART : HRTIMER_RESTART; -} - -static -void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime) -{ - rt_b->rt_period = ns_to_ktime(period); - rt_b->rt_runtime = runtime; - - raw_spin_lock_init(&rt_b->rt_runtime_lock); - - hrtimer_init(&rt_b->rt_period_timer, - CLOCK_MONOTONIC, HRTIMER_MODE_REL); - rt_b->rt_period_timer.function = sched_rt_period_timer; -} - -static inline int rt_bandwidth_enabled(void) -{ - return sysctl_sched_rt_runtime >= 0; -} - -static void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period) +void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period) { unsigned long delta; ktime_t soft, hard, now; @@ -217,580 +104,12 @@ static void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period) } } -static void start_rt_bandwidth(struct rt_bandwidth *rt_b) -{ - if (!rt_bandwidth_enabled() || rt_b->rt_runtime == RUNTIME_INF) - return; - - if (hrtimer_active(&rt_b->rt_period_timer)) - return; - - raw_spin_lock(&rt_b->rt_runtime_lock); - start_bandwidth_timer(&rt_b->rt_period_timer, rt_b->rt_period); - raw_spin_unlock(&rt_b->rt_runtime_lock); -} - -#ifdef CONFIG_RT_GROUP_SCHED -static void destroy_rt_bandwidth(struct rt_bandwidth *rt_b) -{ - hrtimer_cancel(&rt_b->rt_period_timer); -} -#endif - -/* - * sched_domains_mutex serializes calls to init_sched_domains, - * detach_destroy_domains and partition_sched_domains. - */ -static DEFINE_MUTEX(sched_domains_mutex); - -#ifdef CONFIG_CGROUP_SCHED - -#include <linux/cgroup.h> - -struct cfs_rq; - -static LIST_HEAD(task_groups); - -struct cfs_bandwidth { -#ifdef CONFIG_CFS_BANDWIDTH - raw_spinlock_t lock; - ktime_t period; - u64 quota, runtime; - s64 hierarchal_quota; - u64 runtime_expires; - - int idle, timer_active; - struct hrtimer period_timer, slack_timer; - struct list_head throttled_cfs_rq; - - /* statistics */ - int nr_periods, nr_throttled; - u64 throttled_time; -#endif -}; - -/* task group related information */ -struct task_group { - struct cgroup_subsys_state css; - -#ifdef CONFIG_FAIR_GROUP_SCHED - /* schedulable entities of this group on each cpu */ - struct sched_entity **se; - /* runqueue "owned" by this group on each cpu */ - struct cfs_rq **cfs_rq; - unsigned long shares; - - atomic_t load_weight; -#endif - -#ifdef CONFIG_RT_GROUP_SCHED - struct sched_rt_entity **rt_se; - struct rt_rq **rt_rq; - - struct rt_bandwidth rt_bandwidth; -#endif - - struct rcu_head rcu; - struct list_head list; - - struct task_group *parent; - struct list_head siblings; - struct list_head children; - -#ifdef CONFIG_SCHED_AUTOGROUP - struct autogroup *autogroup; -#endif - - struct cfs_bandwidth cfs_bandwidth; -}; - -/* task_group_lock serializes the addition/removal of task groups */ -static DEFINE_SPINLOCK(task_group_lock); - -#ifdef CONFIG_FAIR_GROUP_SCHED - -# define ROOT_TASK_GROUP_LOAD NICE_0_LOAD - -/* - * A weight of 0 or 1 can cause arithmetics problems. - * A weight of a cfs_rq is the sum of weights of which entities - * are queued on this cfs_rq, so a weight of a entity should not be - * too large, so as the shares value of a task group. - * (The default weight is 1024 - so there's no practical - * limitation from this.) - */ -#define MIN_SHARES (1UL << 1) -#define MAX_SHARES (1UL << 18) - -static int root_task_group_load = ROOT_TASK_GROUP_LOAD; -#endif - -/* Default task group. - * Every task in system belong to this group at bootup. - */ -struct task_group root_task_group; - -#endif /* CONFIG_CGROUP_SCHED */ - -/* CFS-related fields in a runqueue */ -struct cfs_rq { - struct load_weight load; - unsigned long nr_running, h_nr_running; - - u64 exec_clock; - u64 min_vruntime; -#ifndef CONFIG_64BIT - u64 min_vruntime_copy; -#endif - - struct rb_root tasks_timeline; - struct rb_node *rb_leftmost; - - struct list_head tasks; - struct list_head *balance_iterator; - - /* - * 'curr' points to currently running entity on this cfs_rq. - * It is set to NULL otherwise (i.e when none are currently running). - */ - struct sched_entity *curr, *next, *last, *skip; - -#ifdef CONFIG_SCHED_DEBUG - unsigned int nr_spread_over; -#endif - -#ifdef CONFIG_FAIR_GROUP_SCHED - struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */ - - /* - * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in - * a hierarchy). Non-leaf lrqs hold other higher schedulable entities - * (like users, containers etc.) - * - * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This - * list is used during load balance. - */ - int on_list; - struct list_head leaf_cfs_rq_list; - struct task_group *tg; /* group that "owns" this runqueue */ - -#ifdef CONFIG_SMP - /* - * the part of load.weight contributed by tasks - */ - unsigned long task_weight; - - /* - * h_load = weight * f(tg) - * - * Where f(tg) is the recursive weight fraction assigned to - * this group. - */ - unsigned long h_load; - - /* - * Maintaining per-cpu shares distribution for group scheduling - * - * load_stamp is the last time we updated the load average - * load_last is the last time we updated the load average and saw load - * load_unacc_exec_time is currently unaccounted execution time - */ - u64 load_avg; - u64 load_period; - u64 load_stamp, load_last, load_unacc_exec_time; - - unsigned long load_contribution; -#endif -#ifdef CONFIG_CFS_BANDWIDTH - int runtime_enabled; - u64 runtime_expires; - s64 runtime_remaining; - - u64 throttled_timestamp; - int throttled, throttle_count; - struct list_head throttled_list; -#endif -#endif -}; - -#ifdef CONFIG_FAIR_GROUP_SCHED -#ifdef CONFIG_CFS_BANDWIDTH -static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg) -{ - return &tg->cfs_bandwidth; -} - -static inline u64 default_cfs_period(void); -static int do_sched_cfs_period_timer(struct cfs_bandwidth *cfs_b, int overrun); -static void do_sched_cfs_slack_timer(struct cfs_bandwidth *cfs_b); - -static enum hrtimer_restart sched_cfs_slack_timer(struct hrtimer *timer) -{ - struct cfs_bandwidth *cfs_b = - container_of(timer, struct cfs_bandwidth, slack_timer); - do_sched_cfs_slack_timer(cfs_b); - - return HRTIMER_NORESTART; -} - -static enum hrtimer_restart sched_cfs_period_timer(struct hrtimer *timer) -{ - struct cfs_bandwidth *cfs_b = - container_of(timer, struct cfs_bandwidth, period_timer); - ktime_t now; - int overrun; - int idle = 0; - - for (;;) { - now = hrtimer_cb_get_time(timer); - overrun = hrtimer_forward(timer, now, cfs_b->period); - - if (!overrun) - break; - - idle = do_sched_cfs_period_timer(cfs_b, overrun); - } - - return idle ? HRTIMER_NORESTART : HRTIMER_RESTART; -} - -static void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b) -{ - raw_spin_lock_init(&cfs_b->lock); - cfs_b->runtime = 0; - cfs_b->quota = RUNTIME_INF; - cfs_b->period = ns_to_ktime(default_cfs_period()); - - INIT_LIST_HEAD(&cfs_b->throttled_cfs_rq); - hrtimer_init(&cfs_b->period_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - cfs_b->period_timer.function = sched_cfs_period_timer; - hrtimer_init(&cfs_b->slack_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - cfs_b->slack_timer.function = sched_cfs_slack_timer; -} - -static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq) -{ - cfs_rq->runtime_enabled = 0; - INIT_LIST_HEAD(&cfs_rq->throttled_list); -} - -/* requires cfs_b->lock, may release to reprogram timer */ -static void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b) -{ - /* - * The timer may be active because we're trying to set a new bandwidth - * period or because we're racing with the tear-down path - * (timer_active==0 becomes visible before the hrtimer call-back - * terminates). In either case we ensure that it's re-programmed - */ - while (unlikely(hrtimer_active(&cfs_b->period_timer))) { - raw_spin_unlock(&cfs_b->lock); - /* ensure cfs_b->lock is available while we wait */ - hrtimer_cancel(&cfs_b->period_timer); - - raw_spin_lock(&cfs_b->lock); - /* if someone else restarted the timer then we're done */ - if (cfs_b->timer_active) - return; - } - - cfs_b->timer_active = 1; - start_bandwidth_timer(&cfs_b->period_timer, cfs_b->period); -} - -static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b) -{ - hrtimer_cancel(&cfs_b->period_timer); - hrtimer_cancel(&cfs_b->slack_timer); -} -#else -static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq) {} -static void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {} -static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {} - -static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg) -{ - return NULL; -} -#endif /* CONFIG_CFS_BANDWIDTH */ -#endif /* CONFIG_FAIR_GROUP_SCHED */ - -/* Real-Time classes' related field in a runqueue: */ -struct rt_rq { - struct rt_prio_array active; - unsigned long rt_nr_running; -#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED - struct { - int curr; /* highest queued rt task prio */ -#ifdef CONFIG_SMP - int next; /* next highest */ -#endif - } highest_prio; -#endif -#ifdef CONFIG_SMP - unsigned long rt_nr_migratory; - unsigned long rt_nr_total; - int overloaded; - struct plist_head pushable_tasks; -#endif - int rt_throttled; - u64 rt_time; - u64 rt_runtime; - /* Nests inside the rq lock: */ - raw_spinlock_t rt_runtime_lock; - -#ifdef CONFIG_RT_GROUP_SCHED - unsigned long rt_nr_boosted; - - struct rq *rq; - struct list_head leaf_rt_rq_list; - struct task_group *tg; -#endif -}; - -#ifdef CONFIG_SMP - -/* - * We add the notion of a root-domain which will be used to define per-domain - * variables. Each exclusive cpuset essentially defines an island domain by - * fully partitioning the member cpus from any other cpuset. Whenever a new - * exclusive cpuset is created, we also create and attach a new root-domain - * object. - * - */ -struct root_domain { - atomic_t refcount; - atomic_t rto_count; - struct rcu_head rcu; - cpumask_var_t span; - cpumask_var_t online; - - /* - * The "RT overload" flag: it gets set if a CPU has more than - * one runnable RT task. - */ - cpumask_var_t rto_mask; - struct cpupri cpupri; -}; - -/* - * By default the system creates a single root-domain with all cpus as - * members (mimicking the global state we have today). - */ -static struct root_domain def_root_domain; - -#endif /* CONFIG_SMP */ - -/* - * This is the main, per-CPU runqueue data structure. - * - * Locking rule: those places that want to lock multiple runqueues - * (such as the load balancing or the thread migration code), lock - * acquire operations must be ordered by ascending &runqueue. - */ -struct rq { - /* runqueue lock: */ - raw_spinlock_t lock; - - /* - * nr_running and cpu_load should be in the same cacheline because - * remote CPUs use both these fields when doing load calculation. - */ - unsigned long nr_running; - #define CPU_LOAD_IDX_MAX 5 - unsigned long cpu_load[CPU_LOAD_IDX_MAX]; - unsigned long last_load_update_tick; -#ifdef CONFIG_NO_HZ - u64 nohz_stamp; - unsigned char nohz_balance_kick; -#endif - int skip_clock_update; - - /* capture load from *all* tasks on this cpu: */ - struct load_weight load; - unsigned long nr_load_updates; - u64 nr_switches; - - struct cfs_rq cfs; - struct rt_rq rt; - -#ifdef CONFIG_FAIR_GROUP_SCHED - /* list of leaf cfs_rq on this cpu: */ - struct list_head leaf_cfs_rq_list; -#endif -#ifdef CONFIG_RT_GROUP_SCHED - struct list_head leaf_rt_rq_list; -#endif - - /* - * This is part of a global counter where only the total sum - * over all CPUs matters. A task can increase this counter on - * one CPU and if it got migrated afterwards it may decrease - * it on another CPU. Always updated under the runqueue lock: - */ - unsigned long nr_uninterruptible; - - struct task_struct *curr, *idle, *stop; - unsigned long next_balance; - struct mm_struct *prev_mm; - - u64 clock; - u64 clock_task; - - atomic_t nr_iowait; - -#ifdef CONFIG_SMP - struct root_domain *rd; - struct sched_domain *sd; - - unsigned long cpu_power; - - unsigned char idle_balance; - /* For active balancing */ - int post_schedule; - int active_balance; - int push_cpu; - struct cpu_stop_work active_balance_work; - /* cpu of this runqueue: */ - int cpu; - int online; - - u64 rt_avg; - u64 age_stamp; - u64 idle_stamp; - u64 avg_idle; -#endif - -#ifdef CONFIG_IRQ_TIME_ACCOUNTING - u64 prev_irq_time; -#endif -#ifdef CONFIG_PARAVIRT - u64 prev_steal_time; -#endif -#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING - u64 prev_steal_time_rq; -#endif - - /* calc_load related fields */ - unsigned long calc_load_update; - long calc_load_active; - -#ifdef CONFIG_SCHED_HRTICK -#ifdef CONFIG_SMP - int hrtick_csd_pending; - struct call_single_data hrtick_csd; -#endif - struct hrtimer hrtick_timer; -#endif - -#ifdef CONFIG_SCHEDSTATS - /* latency stats */ - struct sched_info rq_sched_info; - unsigned long long rq_cpu_time; - /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */ - - /* sys_sched_yield() stats */ - unsigned int yld_count; - - /* schedule() stats */ - unsigned int sched_switch; - unsigned int sched_count; - unsigned int sched_goidle; - - /* try_to_wake_up() stats */ - unsigned int ttwu_count; - unsigned int ttwu_local; -#endif - -#ifdef CONFIG_SMP - struct llist_head wake_list; -#endif -}; - -static DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); - - -static void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags); - -static inline int cpu_of(struct rq *rq) -{ -#ifdef CONFIG_SMP - return rq->cpu; -#else - return 0; -#endif -} - -#define rcu_dereference_check_sched_domain(p) \ - rcu_dereference_check((p), \ - lockdep_is_held(&sched_domains_mutex)) - -/* - * The domain tree (rq->sd) is protected by RCU's quiescent state transition. - * See detach_destroy_domains: synchronize_sched for details. - * - * The domain tree of any CPU may only be accessed from within - * preempt-disabled sections. - */ -#define for_each_domain(cpu, __sd) \ - for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); __sd; __sd = __sd->parent) - -#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) -#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)) - -#ifdef CONFIG_CGROUP_SCHED - -/* - * Return the group to which this tasks belongs. - * - * We use task_subsys_state_check() and extend the RCU verification with - * pi->lock and rq->lock because cpu_cgroup_attach() holds those locks for each - * task it moves into the cgroup. Therefore by holding either of those locks, - * we pin the task to the current cgroup. - */ -static inline struct task_group *task_group(struct task_struct *p) -{ - struct task_group *tg; - struct cgroup_subsys_state *css; - - css = task_subsys_state_check(p, cpu_cgroup_subsys_id, - lockdep_is_held(&p->pi_lock) || - lockdep_is_held(&task_rq(p)->lock)); - tg = container_of(css, struct task_group, css); - - return autogroup_task_group(p, tg); -} - -/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ -static inline void set_task_rq(struct task_struct *p, unsigned int cpu) -{ -#ifdef CONFIG_FAIR_GROUP_SCHED - p->se.cfs_rq = task_group(p)->cfs_rq[cpu]; - p->se.parent = task_group(p)->se[cpu]; -#endif - -#ifdef CONFIG_RT_GROUP_SCHED - p->rt.rt_rq = task_group(p)->rt_rq[cpu]; - p->rt.parent = task_group(p)->rt_se[cpu]; -#endif -} - -#else /* CONFIG_CGROUP_SCHED */ - -static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } -static inline struct task_group *task_group(struct task_struct *p) -{ - return NULL; -} - -#endif /* CONFIG_CGROUP_SCHED */ +DEFINE_MUTEX(sched_domains_mutex); +DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); static void update_rq_clock_task(struct rq *rq, s64 delta); -static void update_rq_clock(struct rq *rq) +void update_rq_clock(struct rq *rq) { s64 delta; @@ -803,44 +122,14 @@ static void update_rq_clock(struct rq *rq) } /* - * Tunables that become constants when CONFIG_SCHED_DEBUG is off: - */ -#ifdef CONFIG_SCHED_DEBUG -# define const_debug __read_mostly -#else -# define const_debug static const -#endif - -/** - * runqueue_is_locked - Returns true if the current cpu runqueue is locked - * @cpu: the processor in question. - * - * 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(int cpu) -{ - return raw_spin_is_locked(&cpu_rq(cpu)->lock); -} - -/* * Debugging: various feature bits */ #define SCHED_FEAT(name, enabled) \ - __SCHED_FEAT_##name , - -enum { -#include "sched_features.h" -}; - -#undef SCHED_FEAT - -#define SCHED_FEAT(name, enabled) \ (1UL << __SCHED_FEAT_##name) * enabled | const_debug unsigned int sysctl_sched_features = -#include "sched_features.h" +#include "features.h" 0; #undef SCHED_FEAT @@ -850,7 +139,7 @@ const_debug unsigned int sysctl_sched_features = #name , static __read_mostly char *sched_feat_names[] = { -#include "sched_features.h" +#include "features.h" NULL }; @@ -860,7 +149,7 @@ static int sched_feat_show(struct seq_file *m, void *v) { int i; - for (i = 0; sched_feat_names[i]; i++) { + for (i = 0; i < __SCHED_FEAT_NR; i++) { if (!(sysctl_sched_features & (1UL << i))) seq_puts(m, "NO_"); seq_printf(m, "%s ", sched_feat_names[i]); @@ -870,6 +159,36 @@ static int sched_feat_show(struct seq_file *m, void *v) return 0; } +#ifdef HAVE_JUMP_LABEL + +#define jump_label_key__true jump_label_key_enabled +#define jump_label_key__false jump_label_key_disabled + +#define SCHED_FEAT(name, enabled) \ + jump_label_key__##enabled , + +struct jump_label_key sched_feat_keys[__SCHED_FEAT_NR] = { +#include "features.h" +}; + +#undef SCHED_FEAT + +static void sched_feat_disable(int i) +{ + if (jump_label_enabled(&sched_feat_keys[i])) + jump_label_dec(&sched_feat_keys[i]); +} + +static void sched_feat_enable(int i) +{ + if (!jump_label_enabled(&sched_feat_keys[i])) + jump_label_inc(&sched_feat_keys[i]); +} +#else +static void sched_feat_disable(int i) { }; +static void sched_feat_enable(int i) { }; +#endif /* HAVE_JUMP_LABEL */ + static ssize_t sched_feat_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) @@ -893,17 +212,20 @@ sched_feat_write(struct file *filp, const char __user *ubuf, cmp += 3; } - for (i = 0; sched_feat_names[i]; i++) { + for (i = 0; i < __SCHED_FEAT_NR; i++) { if (strcmp(cmp, sched_feat_names[i]) == 0) { - if (neg) + if (neg) { sysctl_sched_features &= ~(1UL << i); - else + sched_feat_disable(i); + } else { sysctl_sched_features |= (1UL << i); + sched_feat_enable(i); + } break; } } - if (!sched_feat_names[i]) + if (i == __SCHED_FEAT_NR) return -EINVAL; *ppos += cnt; @@ -932,10 +254,7 @@ static __init int sched_init_debug(void) return 0; } late_initcall(sched_init_debug); - -#endif - -#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) +#endif /* CONFIG_SCHED_DEBUG */ /* * Number of tasks to iterate in a single balance run. @@ -957,7 +276,7 @@ const_debug unsigned int sysctl_sched_time_avg = MSEC_PER_SEC; */ unsigned int sysctl_sched_rt_period = 1000000; -static __read_mostly int scheduler_running; +__read_mostly int scheduler_running; /* * part of the period that we allow rt tasks to run in us. @@ -965,112 +284,7 @@ static __read_mostly int scheduler_running; */ int sysctl_sched_rt_runtime = 950000; -static inline u64 global_rt_period(void) -{ - return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; -} - -static inline u64 global_rt_runtime(void) -{ - if (sysctl_sched_rt_runtime < 0) - return RUNTIME_INF; - return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; -} - -#ifndef prepare_arch_switch -# define prepare_arch_switch(next) do { } while (0) -#endif -#ifndef finish_arch_switch -# define finish_arch_switch(prev) do { } while (0) -#endif - -static inline int task_current(struct rq *rq, struct task_struct *p) -{ - return rq->curr == p; -} - -static inline int task_running(struct rq *rq, struct task_struct *p) -{ -#ifdef CONFIG_SMP - return p->on_cpu; -#else - return task_current(rq, p); -#endif -} - -#ifndef __ARCH_WANT_UNLOCKED_CTXSW -static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) -{ -#ifdef CONFIG_SMP - /* - * We can optimise this out completely for !SMP, because the - * SMP rebalancing from interrupt is the only thing that cares - * here. - */ - next->on_cpu = 1; -#endif -} - -static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) -{ -#ifdef CONFIG_SMP - /* - * After ->on_cpu is cleared, the task can be moved to a different CPU. - * We must ensure this doesn't happen until the switch is completely - * finished. - */ - smp_wmb(); - prev->on_cpu = 0; -#endif -#ifdef CONFIG_DEBUG_SPINLOCK - /* this is a valid case when another task releases the spinlock */ - rq->lock.owner = current; -#endif - /* - * If we are tracking spinlock dependencies then we have to - * fix up the runqueue lock - which gets 'carried over' from - * prev into current: - */ - spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_); - - raw_spin_unlock_irq(&rq->lock); -} - -#else /* __ARCH_WANT_UNLOCKED_CTXSW */ -static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) -{ -#ifdef CONFIG_SMP - /* - * We can optimise this out completely for !SMP, because the - * SMP rebalancing from interrupt is the only thing that cares - * here. - */ - next->on_cpu = 1; -#endif -#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW - raw_spin_unlock_irq(&rq->lock); -#else - raw_spin_unlock(&rq->lock); -#endif -} - -static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) -{ -#ifdef CONFIG_SMP - /* - * After ->on_cpu is cleared, the task can be moved to a different CPU. - * We must ensure this doesn't happen until the switch is completely - * finished. - */ - smp_wmb(); - prev->on_cpu = 0; -#endif -#ifndef __ARCH_WANT_INTERRUPTS_ON_CTXSW - local_irq_enable(); -#endif -} -#endif /* __ARCH_WANT_UNLOCKED_CTXSW */ /* * __task_rq_lock - lock the rq @p resides on. @@ -1153,20 +367,6 @@ static struct rq *this_rq_lock(void) * rq->lock. */ -/* - * Use hrtick when: - * - enabled by features - * - hrtimer is actually high res - */ -static inline int hrtick_enabled(struct rq *rq) -{ - if (!sched_feat(HRTICK)) - return 0; - if (!cpu_active(cpu_of(rq))) - return 0; - return hrtimer_is_hres_active(&rq->hrtick_timer); -} - static void hrtick_clear(struct rq *rq) { if (hrtimer_active(&rq->hrtick_timer)) @@ -1210,7 +410,7 @@ static void __hrtick_start(void *arg) * * called with rq->lock held and irqs disabled */ -static void hrtick_start(struct rq *rq, u64 delay) +void hrtick_start(struct rq *rq, u64 delay) { struct hrtimer *timer = &rq->hrtick_timer; ktime_t time = ktime_add_ns(timer->base->get_time(), delay); @@ -1254,7 +454,7 @@ static __init void init_hrtick(void) * * called with rq->lock held and irqs disabled */ -static void hrtick_start(struct rq *rq, u64 delay) +void hrtick_start(struct rq *rq, u64 delay) { __hrtimer_start_range_ns(&rq->hrtick_timer, ns_to_ktime(delay), 0, HRTIMER_MODE_REL_PINNED, 0); @@ -1305,7 +505,7 @@ static inline void init_hrtick(void) #define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG) #endif -static void resched_task(struct task_struct *p) +void resched_task(struct task_struct *p) { int cpu; @@ -1326,7 +526,7 @@ static void resched_task(struct task_struct *p) smp_send_reschedule(cpu); } -static void resched_cpu(int cpu) +void resched_cpu(int cpu) { struct rq *rq = cpu_rq(cpu); unsigned long flags; @@ -1407,7 +607,8 @@ void wake_up_idle_cpu(int cpu) static inline bool got_nohz_idle_kick(void) { - return idle_cpu(smp_processor_id()) && this_rq()->nohz_balance_kick; + int cpu = smp_processor_id(); + return idle_cpu(cpu) && test_bit(NOHZ_BALANCE_KICK, nohz_flags(cpu)); } #else /* CONFIG_NO_HZ */ @@ -1419,12 +620,7 @@ static inline bool got_nohz_idle_kick(void) #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) +void sched_avg_update(struct rq *rq) { s64 period = sched_avg_period(); @@ -1440,193 +636,23 @@ static void sched_avg_update(struct rq *rq) } } -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) +void resched_task(struct task_struct *p) { assert_raw_spin_locked(&task_rq(p)->lock); set_tsk_need_resched(p); } - -static void sched_rt_avg_update(struct rq *rq, u64 rt_delta) -{ -} - -static void sched_avg_update(struct rq *rq) -{ -} #endif /* CONFIG_SMP */ -#if BITS_PER_LONG == 32 -# define WMULT_CONST (~0UL) -#else -# define WMULT_CONST (1UL << 32) -#endif - -#define WMULT_SHIFT 32 - -/* - * Shift right and round: - */ -#define SRR(x, y) (((x) + (1UL << ((y) - 1))) >> (y)) - -/* - * delta *= weight / lw - */ -static unsigned long -calc_delta_mine(unsigned long delta_exec, unsigned long weight, - struct load_weight *lw) -{ - u64 tmp; - - /* - * weight can be less than 2^SCHED_LOAD_RESOLUTION for task group sched - * entities since MIN_SHARES = 2. Treat weight as 1 if less than - * 2^SCHED_LOAD_RESOLUTION. - */ - if (likely(weight > (1UL << SCHED_LOAD_RESOLUTION))) - tmp = (u64)delta_exec * scale_load_down(weight); - else - tmp = (u64)delta_exec; - - if (!lw->inv_weight) { - unsigned long w = scale_load_down(lw->weight); - - if (BITS_PER_LONG > 32 && unlikely(w >= WMULT_CONST)) - lw->inv_weight = 1; - else if (unlikely(!w)) - lw->inv_weight = WMULT_CONST; - else - lw->inv_weight = WMULT_CONST / w; - } - - /* - * Check whether we'd overflow the 64-bit multiplication: - */ - if (unlikely(tmp > WMULT_CONST)) - tmp = SRR(SRR(tmp, WMULT_SHIFT/2) * lw->inv_weight, - WMULT_SHIFT/2); - else - tmp = SRR(tmp * lw->inv_weight, WMULT_SHIFT); - - return (unsigned long)min(tmp, (u64)(unsigned long)LONG_MAX); -} - -static inline void update_load_add(struct load_weight *lw, unsigned long inc) -{ - lw->weight += inc; - lw->inv_weight = 0; -} - -static inline void update_load_sub(struct load_weight *lw, unsigned long dec) -{ - lw->weight -= dec; - lw->inv_weight = 0; -} - -static inline void update_load_set(struct load_weight *lw, unsigned long w) -{ - lw->weight = w; - lw->inv_weight = 0; -} - -/* - * To aid in avoiding the subversion of "niceness" due to uneven distribution - * of tasks with abnormal "nice" values across CPUs the contribution that - * each task makes to its run queue's load is weighted according to its - * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a - * scaled version of the new time slice allocation that they receive on time - * slice expiry etc. - */ - -#define WEIGHT_IDLEPRIO 3 -#define WMULT_IDLEPRIO 1431655765 - -/* - * Nice levels are multiplicative, with a gentle 10% change for every - * nice level changed. I.e. when a CPU-bound task goes from nice 0 to - * nice 1, it will get ~10% less CPU time than another CPU-bound task - * that remained on nice 0. - * - * The "10% effect" is relative and cumulative: from _any_ nice level, - * if you go up 1 level, it's -10% CPU usage, if you go down 1 level - * it's +10% CPU usage. (to achieve that we use a multiplier of 1.25. - * If a task goes up by ~10% and another task goes down by ~10% then - * the relative distance between them is ~25%.) - */ -static const int prio_to_weight[40] = { - /* -20 */ 88761, 71755, 56483, 46273, 36291, - /* -15 */ 29154, 23254, 18705, 14949, 11916, - /* -10 */ 9548, 7620, 6100, 4904, 3906, - /* -5 */ 3121, 2501, 1991, 1586, 1277, - /* 0 */ 1024, 820, 655, 526, 423, - /* 5 */ 335, 272, 215, 172, 137, - /* 10 */ 110, 87, 70, 56, 45, - /* 15 */ 36, 29, 23, 18, 15, -}; - -/* - * Inverse (2^32/x) values of the prio_to_weight[] array, precalculated. - * - * In cases where the weight does not change often, we can use the - * precalculated inverse to speed up arithmetics by turning divisions - * into multiplications: - */ -static const u32 prio_to_wmult[40] = { - /* -20 */ 48388, 59856, 76040, 92818, 118348, - /* -15 */ 147320, 184698, 229616, 287308, 360437, - /* -10 */ 449829, 563644, 704093, 875809, 1099582, - /* -5 */ 1376151, 1717300, 2157191, 2708050, 3363326, - /* 0 */ 4194304, 5237765, 6557202, 8165337, 10153587, - /* 5 */ 12820798, 15790321, 19976592, 24970740, 31350126, - /* 10 */ 39045157, 49367440, 61356676, 76695844, 95443717, - /* 15 */ 119304647, 148102320, 186737708, 238609294, 286331153, -}; - -/* Time spent by the tasks of the cpu accounting group executing in ... */ -enum cpuacct_stat_index { - CPUACCT_STAT_USER, /* ... user mode */ - CPUACCT_STAT_SYSTEM, /* ... kernel mode */ - - CPUACCT_STAT_NSTATS, -}; - -#ifdef CONFIG_CGROUP_CPUACCT -static void cpuacct_charge(struct task_struct *tsk, u64 cputime); -static void cpuacct_update_stats(struct task_struct *tsk, - enum cpuacct_stat_index idx, cputime_t val); -#else -static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {} -static inline void cpuacct_update_stats(struct task_struct *tsk, - enum cpuacct_stat_index idx, cputime_t val) {} -#endif - -static inline void inc_cpu_load(struct rq *rq, unsigned long load) -{ - update_load_add(&rq->load, load); -} - -static inline void dec_cpu_load(struct rq *rq, unsigned long load) -{ - update_load_sub(&rq->load, load); -} - #if defined(CONFIG_RT_GROUP_SCHED) || (defined(CONFIG_FAIR_GROUP_SCHED) && \ (defined(CONFIG_SMP) || defined(CONFIG_CFS_BANDWIDTH))) -typedef int (*tg_visitor)(struct task_group *, void *); - /* * Iterate task_group tree rooted at *from, calling @down when first entering a * node and @up when leaving it for the final time. * * Caller must hold rcu_lock or sufficient equivalent. */ -static int walk_tg_tree_from(struct task_group *from, +int walk_tg_tree_from(struct task_group *from, tg_visitor down, tg_visitor up, void *data) { struct task_group *parent, *child; @@ -1657,270 +683,13 @@ out: return ret; } -/* - * Iterate the full tree, calling @down when first entering a node and @up when - * leaving it for the final time. - * - * Caller must hold rcu_lock or sufficient equivalent. - */ - -static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data) -{ - return walk_tg_tree_from(&root_task_group, down, up, data); -} - -static int tg_nop(struct task_group *tg, void *data) +int tg_nop(struct task_group *tg, void *data) { return 0; } #endif -#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; -} - -/* - * 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 unsigned long power_of(int cpu) -{ - return cpu_rq(cpu)->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) -{ - struct rq *rq = cpu_rq(cpu); - unsigned long nr_running = ACCESS_ONCE(rq->nr_running); - - if (nr_running) - return rq->load.weight / nr_running; - - return 0; -} - -#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 - * invocations. This assures that the double_lock is acquired using the - * same underlying policy as the spinlock_t on this architecture, which - * reduces latency compared to the unfair variant below. However, it - * also adds more overhead and therefore may reduce throughput. - */ -static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) - __releases(this_rq->lock) - __acquires(busiest->lock) - __acquires(this_rq->lock) -{ - raw_spin_unlock(&this_rq->lock); - double_rq_lock(this_rq, busiest); - - return 1; -} - -#else -/* - * Unfair double_lock_balance: Optimizes throughput at the expense of - * latency by eliminating extra atomic operations when the locks are - * already in proper order on entry. This favors lower cpu-ids and will - * grant the double lock to lower cpus over higher ids under contention, - * regardless of entry order into the function. - */ -static int _double_lock_balance(struct rq *this_rq, struct rq *busiest) - __releases(this_rq->lock) - __acquires(busiest->lock) - __acquires(this_rq->lock) -{ - int ret = 0; - - if (unlikely(!raw_spin_trylock(&busiest->lock))) { - if (busiest < this_rq) { - raw_spin_unlock(&this_rq->lock); - raw_spin_lock(&busiest->lock); - raw_spin_lock_nested(&this_rq->lock, - SINGLE_DEPTH_NESTING); - ret = 1; - } else - raw_spin_lock_nested(&busiest->lock, - SINGLE_DEPTH_NESTING); - } - return ret; -} - -#endif /* CONFIG_PREEMPT */ - -/* - * double_lock_balance - lock the busiest runqueue, this_rq is locked already. - */ -static int double_lock_balance(struct rq *this_rq, struct rq *busiest) -{ - if (unlikely(!irqs_disabled())) { - /* printk() doesn't work good under rq->lock */ - raw_spin_unlock(&this_rq->lock); - BUG_ON(1); - } - - return _double_lock_balance(this_rq, busiest); -} - -static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) - __releases(busiest->lock) -{ - raw_spin_unlock(&busiest->lock); - lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_); -} - -/* - * double_rq_lock - safely lock two runqueues - * - * Note this does not disable interrupts like task_rq_lock, - * you need to do so manually before calling. - */ -static void double_rq_lock(struct rq *rq1, struct rq *rq2) - __acquires(rq1->lock) - __acquires(rq2->lock) -{ - BUG_ON(!irqs_disabled()); - if (rq1 == rq2) { - raw_spin_lock(&rq1->lock); - __acquire(rq2->lock); /* Fake it out ;) */ - } else { - if (rq1 < rq2) { - raw_spin_lock(&rq1->lock); - raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING); - } else { - raw_spin_lock(&rq2->lock); - raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING); - } - } -} - -/* - * double_rq_unlock - safely unlock two runqueues - * - * Note this does not restore interrupts like task_rq_unlock, - * you need to do so manually after calling. - */ -static void double_rq_unlock(struct rq *rq1, struct rq *rq2) - __releases(rq1->lock) - __releases(rq2->lock) -{ - raw_spin_unlock(&rq1->lock); - if (rq1 != rq2) - raw_spin_unlock(&rq2->lock); - else - __release(rq2->lock); -} - -#else /* CONFIG_SMP */ - -/* - * double_rq_lock - safely lock two runqueues - * - * Note this does not disable interrupts like task_rq_lock, - * you need to do so manually before calling. - */ -static void double_rq_lock(struct rq *rq1, struct rq *rq2) - __acquires(rq1->lock) - __acquires(rq2->lock) -{ - BUG_ON(!irqs_disabled()); - BUG_ON(rq1 != rq2); - raw_spin_lock(&rq1->lock); - __acquire(rq2->lock); /* Fake it out ;) */ -} - -/* - * double_rq_unlock - safely unlock two runqueues - * - * Note this does not restore interrupts like task_rq_unlock, - * you need to do so manually after calling. - */ -static void double_rq_unlock(struct rq *rq1, struct rq *rq2) - __releases(rq1->lock) - __releases(rq2->lock) -{ - BUG_ON(rq1 != rq2); - raw_spin_unlock(&rq1->lock); - __release(rq2->lock); -} - -#endif - -static void calc_load_account_idle(struct rq *this_rq); -static void update_sysctl(void); -static int get_update_sysctl_factor(void); -static void update_cpu_load(struct rq *this_rq); - -static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) -{ - set_task_rq(p, cpu); -#ifdef CONFIG_SMP - /* - * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be - * successfully executed on another CPU. We must ensure that updates of - * per-task data have been completed by this moment. - */ - smp_wmb(); - task_thread_info(p)->cpu = cpu; -#endif -} - -static const struct sched_class rt_sched_class; - -#define sched_class_highest (&stop_sched_class) -#define for_each_class(class) \ - for (class = sched_class_highest; class; class = class->next) - -#include "sched_stats.h" - -static void inc_nr_running(struct rq *rq) -{ - rq->nr_running++; -} - -static void dec_nr_running(struct rq *rq) -{ - rq->nr_running--; -} +void update_cpu_load(struct rq *this_rq); static void set_load_weight(struct task_struct *p) { @@ -1957,7 +726,7 @@ static void dequeue_task(struct rq *rq, struct task_struct *p, int flags) /* * activate_task - move a task to the runqueue. */ -static void activate_task(struct rq *rq, struct task_struct *p, int flags) +void activate_task(struct rq *rq, struct task_struct *p, int flags) { if (task_contributes_to_load(p)) rq->nr_uninterruptible--; @@ -1968,7 +737,7 @@ static void activate_task(struct rq *rq, struct task_struct *p, int flags) /* * deactivate_task - remove a task from the runqueue. */ -static void deactivate_task(struct rq *rq, struct task_struct *p, int flags) +void deactivate_task(struct rq *rq, struct task_struct *p, int flags) { if (task_contributes_to_load(p)) rq->nr_uninterruptible++; @@ -2159,14 +928,14 @@ static void update_rq_clock_task(struct rq *rq, s64 delta) #ifdef CONFIG_IRQ_TIME_ACCOUNTING static int irqtime_account_hi_update(void) { - struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat; + u64 *cpustat = kcpustat_this_cpu->cpustat; unsigned long flags; u64 latest_ns; int ret = 0; local_irq_save(flags); latest_ns = this_cpu_read(cpu_hardirq_time); - if (cputime64_gt(nsecs_to_cputime64(latest_ns), cpustat->irq)) + if (nsecs_to_cputime64(latest_ns) > cpustat[CPUTIME_IRQ]) ret = 1; local_irq_restore(flags); return ret; @@ -2174,14 +943,14 @@ static int irqtime_account_hi_update(void) static int irqtime_account_si_update(void) { - struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat; + u64 *cpustat = kcpustat_this_cpu->cpustat; unsigned long flags; u64 latest_ns; int ret = 0; local_irq_save(flags); latest_ns = this_cpu_read(cpu_softirq_time); - if (cputime64_gt(nsecs_to_cputime64(latest_ns), cpustat->softirq)) + if (nsecs_to_cputime64(latest_ns) > cpustat[CPUTIME_SOFTIRQ]) ret = 1; local_irq_restore(flags); return ret; @@ -2193,15 +962,6 @@ static int irqtime_account_si_update(void) #endif -#include "sched_idletask.c" -#include "sched_fair.c" -#include "sched_rt.c" -#include "sched_autogroup.c" -#include "sched_stoptask.c" -#ifdef CONFIG_SCHED_DEBUG -# include "sched_debug.c" -#endif - void sched_set_stop_task(int cpu, struct task_struct *stop) { struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 }; @@ -2299,7 +1059,7 @@ static inline void check_class_changed(struct rq *rq, struct task_struct *p, p->sched_class->prio_changed(rq, p, oldprio); } -static void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags) +void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags) { const struct sched_class *class; @@ -2325,38 +1085,6 @@ static void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags) } #ifdef CONFIG_SMP -/* - * Is this task likely cache-hot: - */ -static int -task_hot(struct task_struct *p, u64 now, struct sched_domain *sd) -{ - s64 delta; - - if (p->sched_class != &fair_sched_class) - return 0; - - if (unlikely(p->policy == SCHED_IDLE)) - return 0; - - /* - * Buddy candidates are cache hot: - */ - if (sched_feat(CACHE_HOT_BUDDY) && this_rq()->nr_running && - (&p->se == cfs_rq_of(&p->se)->next || - &p->se == cfs_rq_of(&p->se)->last)) - return 1; - - if (sysctl_sched_migration_cost == -1) - return 1; - if (sysctl_sched_migration_cost == 0) - return 0; - - delta = now - p->se.exec_start; - - return delta < (s64)sysctl_sched_migration_cost; -} - void set_task_cpu(struct task_struct *p, unsigned int new_cpu) { #ifdef CONFIG_SCHED_DEBUG @@ -2783,6 +1511,11 @@ static int ttwu_activate_remote(struct task_struct *p, int wake_flags) } #endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */ + +static inline int ttwu_share_cache(int this_cpu, int that_cpu) +{ + return per_cpu(sd_llc_id, this_cpu) == per_cpu(sd_llc_id, that_cpu); +} #endif /* CONFIG_SMP */ static void ttwu_queue(struct task_struct *p, int cpu) @@ -2790,7 +1523,7 @@ static void ttwu_queue(struct task_struct *p, int cpu) struct rq *rq = cpu_rq(cpu); #if defined(CONFIG_SMP) - if (sched_feat(TTWU_QUEUE) && cpu != smp_processor_id()) { + if (sched_feat(TTWU_QUEUE) && !ttwu_share_cache(smp_processor_id(), cpu)) { sched_clock_cpu(cpu); /* sync clocks x-cpu */ ttwu_queue_remote(p, cpu); return; @@ -3204,6 +1937,7 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev) local_irq_enable(); #endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */ finish_lock_switch(rq, prev); + trace_sched_stat_sleeptime(current, rq->clock); fire_sched_in_preempt_notifiers(current); if (mm) @@ -3439,7 +2173,7 @@ calc_load(unsigned long load, unsigned long exp, unsigned long active) */ static atomic_long_t calc_load_tasks_idle; -static void calc_load_account_idle(struct rq *this_rq) +void calc_load_account_idle(struct rq *this_rq) { long delta; @@ -3583,7 +2317,7 @@ static void calc_global_nohz(unsigned long ticks) */ } #else -static void calc_load_account_idle(struct rq *this_rq) +void calc_load_account_idle(struct rq *this_rq) { } @@ -3726,7 +2460,7 @@ decay_load_missed(unsigned long load, unsigned long missed_updates, int idx) * scheduler tick (TICK_NSEC). With tickless idle this will not be called * every tick. We fix it up based on jiffies. */ -static void update_cpu_load(struct rq *this_rq) +void update_cpu_load(struct rq *this_rq) { unsigned long this_load = this_rq->load.weight; unsigned long curr_jiffies = jiffies; @@ -3804,8 +2538,10 @@ unlock: #endif DEFINE_PER_CPU(struct kernel_stat, kstat); +DEFINE_PER_CPU(struct kernel_cpustat, kernel_cpustat); EXPORT_PER_CPU_SYMBOL(kstat); +EXPORT_PER_CPU_SYMBOL(kernel_cpustat); /* * Return any ns on the sched_clock that have not yet been accounted in @@ -3858,6 +2594,42 @@ unsigned long long task_sched_runtime(struct task_struct *p) return ns; } +#ifdef CONFIG_CGROUP_CPUACCT +struct cgroup_subsys cpuacct_subsys; +struct cpuacct root_cpuacct; +#endif + +static inline void task_group_account_field(struct task_struct *p, int index, + u64 tmp) +{ +#ifdef CONFIG_CGROUP_CPUACCT + struct kernel_cpustat *kcpustat; + struct cpuacct *ca; +#endif + /* + * Since all updates are sure to touch the root cgroup, we + * get ourselves ahead and touch it first. If the root cgroup + * is the only cgroup, then nothing else should be necessary. + * + */ + __get_cpu_var(kernel_cpustat).cpustat[index] += tmp; + +#ifdef CONFIG_CGROUP_CPUACCT + if (unlikely(!cpuacct_subsys.active)) + return; + + rcu_read_lock(); + ca = task_ca(p); + while (ca && (ca != &root_cpuacct)) { + kcpustat = this_cpu_ptr(ca->cpustat); + kcpustat->cpustat[index] += tmp; + ca = parent_ca(ca); + } + rcu_read_unlock(); +#endif +} + + /* * Account user cpu time to a process. * @p: the process that the cpu time gets accounted to @@ -3867,22 +2639,18 @@ unsigned long long task_sched_runtime(struct task_struct *p) void account_user_time(struct task_struct *p, cputime_t cputime, cputime_t cputime_scaled) { - struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat; - cputime64_t tmp; + int index; /* Add user time to process. */ - p->utime = cputime_add(p->utime, cputime); - p->utimescaled = cputime_add(p->utimescaled, cputime_scaled); + p->utime += cputime; + p->utimescaled += cputime_scaled; account_group_user_time(p, cputime); + index = (TASK_NICE(p) > 0) ? CPUTIME_NICE : CPUTIME_USER; + /* Add user time to cpustat. */ - tmp = cputime_to_cputime64(cputime); - if (TASK_NICE(p) > 0) - cpustat->nice = cputime64_add(cpustat->nice, tmp); - else - cpustat->user = cputime64_add(cpustat->user, tmp); + task_group_account_field(p, index, (__force u64) cputime); - cpuacct_update_stats(p, CPUACCT_STAT_USER, cputime); /* Account for user time used */ acct_update_integrals(p); } @@ -3896,24 +2664,21 @@ void account_user_time(struct task_struct *p, cputime_t cputime, static void account_guest_time(struct task_struct *p, cputime_t cputime, cputime_t cputime_scaled) { - cputime64_t tmp; - struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat; - - tmp = cputime_to_cputime64(cputime); + u64 *cpustat = kcpustat_this_cpu->cpustat; /* Add guest time to process. */ - p->utime = cputime_add(p->utime, cputime); - p->utimescaled = cputime_add(p->utimescaled, cputime_scaled); + p->utime += cputime; + p->utimescaled += cputime_scaled; account_group_user_time(p, cputime); - p->gtime = cputime_add(p->gtime, cputime); + p->gtime += cputime; /* Add guest time to cpustat. */ if (TASK_NICE(p) > 0) { - cpustat->nice = cputime64_add(cpustat->nice, tmp); - cpustat->guest_nice = cputime64_add(cpustat->guest_nice, tmp); + cpustat[CPUTIME_NICE] += (__force u64) cputime; + cpustat[CPUTIME_GUEST_NICE] += (__force u64) cputime; } else { - cpustat->user = cputime64_add(cpustat->user, tmp); - cpustat->guest = cputime64_add(cpustat->guest, tmp); + cpustat[CPUTIME_USER] += (__force u64) cputime; + cpustat[CPUTIME_GUEST] += (__force u64) cputime; } } @@ -3926,18 +2691,15 @@ static void account_guest_time(struct task_struct *p, cputime_t cputime, */ static inline void __account_system_time(struct task_struct *p, cputime_t cputime, - cputime_t cputime_scaled, cputime64_t *target_cputime64) + cputime_t cputime_scaled, int index) { - cputime64_t tmp = cputime_to_cputime64(cputime); - /* Add system time to process. */ - p->stime = cputime_add(p->stime, cputime); - p->stimescaled = cputime_add(p->stimescaled, cputime_scaled); + p->stime += cputime; + p->stimescaled += cputime_scaled; account_group_system_time(p, cputime); /* Add system time to cpustat. */ - *target_cputime64 = cputime64_add(*target_cputime64, tmp); - cpuacct_update_stats(p, CPUACCT_STAT_SYSTEM, cputime); + task_group_account_field(p, index, (__force u64) cputime); /* Account for system time used */ acct_update_integrals(p); @@ -3953,8 +2715,7 @@ void __account_system_time(struct task_struct *p, cputime_t cputime, void account_system_time(struct task_struct *p, int hardirq_offset, cputime_t cputime, cputime_t cputime_scaled) { - struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat; - cputime64_t *target_cputime64; + int index; if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0)) { account_guest_time(p, cputime, cputime_scaled); @@ -3962,13 +2723,13 @@ void account_system_time(struct task_struct *p, int hardirq_offset, } if (hardirq_count() - hardirq_offset) - target_cputime64 = &cpustat->irq; + index = CPUTIME_IRQ; else if (in_serving_softirq()) - target_cputime64 = &cpustat->softirq; + index = CPUTIME_SOFTIRQ; else - target_cputime64 = &cpustat->system; + index = CPUTIME_SYSTEM; - __account_system_time(p, cputime, cputime_scaled, target_cputime64); + __account_system_time(p, cputime, cputime_scaled, index); } /* @@ -3977,10 +2738,9 @@ void account_system_time(struct task_struct *p, int hardirq_offset, */ void account_steal_time(cputime_t cputime) { - struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat; - cputime64_t cputime64 = cputime_to_cputime64(cputime); + u64 *cpustat = kcpustat_this_cpu->cpustat; - cpustat->steal = cputime64_add(cpustat->steal, cputime64); + cpustat[CPUTIME_STEAL] += (__force u64) cputime; } /* @@ -3989,14 +2749,13 @@ void account_steal_time(cputime_t cputime) */ void account_idle_time(cputime_t cputime) { - struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat; - cputime64_t cputime64 = cputime_to_cputime64(cputime); + u64 *cpustat = kcpustat_this_cpu->cpustat; struct rq *rq = this_rq(); if (atomic_read(&rq->nr_iowait) > 0) - cpustat->iowait = cputime64_add(cpustat->iowait, cputime64); + cpustat[CPUTIME_IOWAIT] += (__force u64) cputime; else - cpustat->idle = cputime64_add(cpustat->idle, cputime64); + cpustat[CPUTIME_IDLE] += (__force u64) cputime; } static __always_inline bool steal_account_process_tick(void) @@ -4046,16 +2805,15 @@ static void irqtime_account_process_tick(struct task_struct *p, int user_tick, struct rq *rq) { cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy); - cputime64_t tmp = cputime_to_cputime64(cputime_one_jiffy); - struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat; + u64 *cpustat = kcpustat_this_cpu->cpustat; if (steal_account_process_tick()) return; if (irqtime_account_hi_update()) { - cpustat->irq = cputime64_add(cpustat->irq, tmp); + cpustat[CPUTIME_IRQ] += (__force u64) cputime_one_jiffy; } else if (irqtime_account_si_update()) { - cpustat->softirq = cputime64_add(cpustat->softirq, tmp); + cpustat[CPUTIME_SOFTIRQ] += (__force u64) cputime_one_jiffy; } else if (this_cpu_ksoftirqd() == p) { /* * ksoftirqd time do not get accounted in cpu_softirq_time. @@ -4063,7 +2821,7 @@ static void irqtime_account_process_tick(struct task_struct *p, int user_tick, * Also, p->stime needs to be updated for ksoftirqd. */ __account_system_time(p, cputime_one_jiffy, one_jiffy_scaled, - &cpustat->softirq); + CPUTIME_SOFTIRQ); } else if (user_tick) { account_user_time(p, cputime_one_jiffy, one_jiffy_scaled); } else if (p == rq->idle) { @@ -4072,7 +2830,7 @@ static void irqtime_account_process_tick(struct task_struct *p, int user_tick, account_guest_time(p, cputime_one_jiffy, one_jiffy_scaled); } else { __account_system_time(p, cputime_one_jiffy, one_jiffy_scaled, - &cpustat->system); + CPUTIME_SYSTEM); } } @@ -4171,7 +2929,7 @@ void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st) void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st) { - cputime_t rtime, utime = p->utime, total = cputime_add(utime, p->stime); + cputime_t rtime, utime = p->utime, total = utime + p->stime; /* * Use CFS's precise accounting: @@ -4179,11 +2937,11 @@ void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st) rtime = nsecs_to_cputime(p->se.sum_exec_runtime); if (total) { - u64 temp = rtime; + u64 temp = (__force u64) rtime; - temp *= utime; - do_div(temp, total); - utime = (cputime_t)temp; + temp *= (__force u64) utime; + do_div(temp, (__force u32) total); + utime = (__force cputime_t) temp; } else utime = rtime; @@ -4191,7 +2949,7 @@ void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st) * Compare with previous values, to keep monotonicity: */ p->prev_utime = max(p->prev_utime, utime); - p->prev_stime = max(p->prev_stime, cputime_sub(rtime, p->prev_utime)); + p->prev_stime = max(p->prev_stime, rtime - p->prev_utime); *ut = p->prev_utime; *st = p->prev_stime; @@ -4208,21 +2966,20 @@ void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st) thread_group_cputime(p, &cputime); - total = cputime_add(cputime.utime, cputime.stime); + total = cputime.utime + cputime.stime; rtime = nsecs_to_cputime(cputime.sum_exec_runtime); if (total) { - u64 temp = rtime; + u64 temp = (__force u64) rtime; - temp *= cputime.utime; - do_div(temp, total); - utime = (cputime_t)temp; + temp *= (__force u64) cputime.utime; + do_div(temp, (__force u32) total); + utime = (__force cputime_t) temp; } else utime = rtime; sig->prev_utime = max(sig->prev_utime, utime); - sig->prev_stime = max(sig->prev_stime, - cputime_sub(rtime, sig->prev_utime)); + sig->prev_stime = max(sig->prev_stime, rtime - sig->prev_utime); *ut = sig->prev_utime; *st = sig->prev_stime; @@ -4321,6 +3078,9 @@ static noinline void __schedule_bug(struct task_struct *prev) { struct pt_regs *regs = get_irq_regs(); + if (oops_in_progress) + return; + printk(KERN_ERR "BUG: scheduling while atomic: %s/%d/0x%08x\n", prev->comm, prev->pid, preempt_count()); @@ -5570,7 +4330,7 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) goto out_free_cpus_allowed; } retval = -EPERM; - if (!check_same_owner(p) && !task_ns_capable(p, CAP_SYS_NICE)) + if (!check_same_owner(p) && !ns_capable(task_user_ns(p), CAP_SYS_NICE)) goto out_unlock; retval = security_task_setscheduler(p); @@ -5852,6 +4612,13 @@ again: */ if (preempt && rq != p_rq) resched_task(p_rq->curr); + } else { + /* + * We might have set it in task_yield_fair(), but are + * not going to schedule(), so don't want to skip + * the next update. + */ + rq->skip_clock_update = 0; } out: @@ -6019,7 +4786,7 @@ void sched_show_task(struct task_struct *p) free = stack_not_used(p); #endif printk(KERN_CONT "%5lu %5d %6d 0x%08lx\n", free, - task_pid_nr(p), task_pid_nr(p->real_parent), + task_pid_nr(p), task_pid_nr(rcu_dereference(p->real_parent)), (unsigned long)task_thread_info(p)->flags); show_stack(p, NULL); @@ -6118,53 +4885,6 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu) #endif } -/* - * Increase the granularity value when there are more CPUs, - * because with more CPUs the 'effective latency' as visible - * to users decreases. But the relationship is not linear, - * so pick a second-best guess by going with the log2 of the - * number of CPUs. - * - * This idea comes from the SD scheduler of Con Kolivas: - */ -static int get_update_sysctl_factor(void) -{ - unsigned int cpus = min_t(int, num_online_cpus(), 8); - unsigned int factor; - - switch (sysctl_sched_tunable_scaling) { - case SCHED_TUNABLESCALING_NONE: - factor = 1; - break; - case SCHED_TUNABLESCALING_LINEAR: - factor = cpus; - break; - case SCHED_TUNABLESCALING_LOG: - default: - factor = 1 + ilog2(cpus); - break; - } - - return factor; -} - -static void update_sysctl(void) -{ - unsigned int factor = get_update_sysctl_factor(); - -#define SET_SYSCTL(name) \ - (sysctl_##name = (factor) * normalized_sysctl_##name) - SET_SYSCTL(sched_min_granularity); - SET_SYSCTL(sched_latency); - SET_SYSCTL(sched_wakeup_granularity); -#undef SET_SYSCTL -} - -static inline void sched_init_granularity(void) -{ - update_sysctl(); -} - #ifdef CONFIG_SMP void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) { @@ -6351,30 +5071,6 @@ static void calc_global_load_remove(struct rq *rq) rq->calc_load_active = 0; } -#ifdef CONFIG_CFS_BANDWIDTH -static void unthrottle_offline_cfs_rqs(struct rq *rq) -{ - struct cfs_rq *cfs_rq; - - for_each_leaf_cfs_rq(rq, cfs_rq) { - struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg); - - if (!cfs_rq->runtime_enabled) - continue; - - /* - * clock_task is not advancing so we just need to make sure - * there's some valid quota amount - */ - cfs_rq->runtime_remaining = cfs_b->quota; - if (cfs_rq_throttled(cfs_rq)) - unthrottle_cfs_rq(cfs_rq); - } -} -#else -static void unthrottle_offline_cfs_rqs(struct rq *rq) {} -#endif - /* * Migrate all tasks from the rq, sleeping tasks will be migrated by * try_to_wake_up()->select_task_rq(). @@ -6480,7 +5176,7 @@ static void sd_free_ctl_entry(struct ctl_table **tablep) static void set_table_entry(struct ctl_table *entry, const char *procname, void *data, int maxlen, - mode_t mode, proc_handler *proc_handler) + umode_t mode, proc_handler *proc_handler) { entry->procname = procname; entry->data = data; @@ -6980,6 +5676,12 @@ out: return -ENOMEM; } +/* + * By default the system creates a single root-domain with all cpus as + * members (mimicking the global state we have today). + */ +struct root_domain def_root_domain; + static void init_defrootdomain(void) { init_rootdomain(&def_root_domain); @@ -7051,6 +5753,31 @@ static void destroy_sched_domains(struct sched_domain *sd, int cpu) } /* + * Keep a special pointer to the highest sched_domain that has + * SD_SHARE_PKG_RESOURCE set (Last Level Cache Domain) for this + * allows us to avoid some pointer chasing select_idle_sibling(). + * + * Also keep a unique ID per domain (we use the first cpu number in + * the cpumask of the domain), this allows us to quickly tell if + * two cpus are in the same cache domain, see ttwu_share_cache(). + */ +DEFINE_PER_CPU(struct sched_domain *, sd_llc); +DEFINE_PER_CPU(int, sd_llc_id); + +static void update_top_cache_domain(int cpu) +{ + struct sched_domain *sd; + int id = cpu; + + sd = highest_flag_domain(cpu, SD_SHARE_PKG_RESOURCES); + if (sd) + id = cpumask_first(sched_domain_span(sd)); + + rcu_assign_pointer(per_cpu(sd_llc, cpu), sd); + per_cpu(sd_llc_id, cpu) = id; +} + +/* * Attach the domain 'sd' to 'cpu' as its base domain. Callers must * hold the hotplug lock. */ @@ -7089,6 +5816,8 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) tmp = rq->sd; rcu_assign_pointer(rq->sd, sd); destroy_sched_domains(tmp, cpu); + + update_top_cache_domain(cpu); } /* cpus with isolated domains */ @@ -7248,7 +5977,7 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu) continue; sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(), - GFP_KERNEL, cpu_to_node(i)); + GFP_KERNEL, cpu_to_node(cpu)); if (!sg) goto fail; @@ -7386,6 +6115,12 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd) return; update_group_power(sd, cpu); + atomic_set(&sg->sgp->nr_busy_cpus, sg->group_weight); +} + +int __weak arch_sd_sibling_asym_packing(void) +{ + return 0*SD_ASYM_PACKING; } /* @@ -7940,54 +6675,52 @@ static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt) } #ifdef CONFIG_SCHED_MC -static ssize_t sched_mc_power_savings_show(struct sysdev_class *class, - struct sysdev_class_attribute *attr, - char *page) +static ssize_t sched_mc_power_savings_show(struct device *dev, + struct device_attribute *attr, + char *buf) { - return sprintf(page, "%u\n", sched_mc_power_savings); + return sprintf(buf, "%u\n", sched_mc_power_savings); } -static ssize_t sched_mc_power_savings_store(struct sysdev_class *class, - struct sysdev_class_attribute *attr, +static ssize_t sched_mc_power_savings_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) { return sched_power_savings_store(buf, count, 0); } -static SYSDEV_CLASS_ATTR(sched_mc_power_savings, 0644, - sched_mc_power_savings_show, - sched_mc_power_savings_store); +static DEVICE_ATTR(sched_mc_power_savings, 0644, + sched_mc_power_savings_show, + sched_mc_power_savings_store); #endif #ifdef CONFIG_SCHED_SMT -static ssize_t sched_smt_power_savings_show(struct sysdev_class *dev, - struct sysdev_class_attribute *attr, - char *page) +static ssize_t sched_smt_power_savings_show(struct device *dev, + struct device_attribute *attr, + char *buf) { - return sprintf(page, "%u\n", sched_smt_power_savings); + return sprintf(buf, "%u\n", sched_smt_power_savings); } -static ssize_t sched_smt_power_savings_store(struct sysdev_class *dev, - struct sysdev_class_attribute *attr, +static ssize_t sched_smt_power_savings_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) { return sched_power_savings_store(buf, count, 1); } -static SYSDEV_CLASS_ATTR(sched_smt_power_savings, 0644, +static DEVICE_ATTR(sched_smt_power_savings, 0644, sched_smt_power_savings_show, sched_smt_power_savings_store); #endif -int __init sched_create_sysfs_power_savings_entries(struct sysdev_class *cls) +int __init sched_create_sysfs_power_savings_entries(struct device *dev) { int err = 0; #ifdef CONFIG_SCHED_SMT if (smt_capable()) - err = sysfs_create_file(&cls->kset.kobj, - &attr_sched_smt_power_savings.attr); + err = device_create_file(dev, &dev_attr_sched_smt_power_savings); #endif #ifdef CONFIG_SCHED_MC if (!err && mc_capable()) - err = sysfs_create_file(&cls->kset.kobj, - &attr_sched_mc_power_savings.attr); + err = device_create_file(dev, &dev_attr_sched_mc_power_savings); #endif return err; } @@ -8023,29 +6756,6 @@ static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action, } } -static int update_runtime(struct notifier_block *nfb, - unsigned long action, void *hcpu) -{ - int cpu = (int)(long)hcpu; - - switch (action) { - case CPU_DOWN_PREPARE: - case CPU_DOWN_PREPARE_FROZEN: - disable_runtime(cpu_rq(cpu)); - return NOTIFY_OK; - - case CPU_DOWN_FAILED: - case CPU_DOWN_FAILED_FROZEN: - case CPU_ONLINE: - case CPU_ONLINE_FROZEN: - enable_runtime(cpu_rq(cpu)); - return NOTIFY_OK; - - default: - return NOTIFY_DONE; - } -} - void __init sched_init_smp(void) { cpumask_var_t non_isolated_cpus; @@ -8094,104 +6804,11 @@ int in_sched_functions(unsigned long addr) && addr < (unsigned long)__sched_text_end); } -static void init_cfs_rq(struct cfs_rq *cfs_rq) -{ - cfs_rq->tasks_timeline = RB_ROOT; - INIT_LIST_HEAD(&cfs_rq->tasks); - cfs_rq->min_vruntime = (u64)(-(1LL << 20)); -#ifndef CONFIG_64BIT - cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime; -#endif -} - -static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq) -{ - struct rt_prio_array *array; - int i; - - array = &rt_rq->active; - for (i = 0; i < MAX_RT_PRIO; i++) { - INIT_LIST_HEAD(array->queue + i); - __clear_bit(i, array->bitmap); - } - /* delimiter for bitsearch: */ - __set_bit(MAX_RT_PRIO, array->bitmap); - -#if defined CONFIG_SMP - rt_rq->highest_prio.curr = MAX_RT_PRIO; - rt_rq->highest_prio.next = MAX_RT_PRIO; - rt_rq->rt_nr_migratory = 0; - rt_rq->overloaded = 0; - plist_head_init(&rt_rq->pushable_tasks); -#endif - - rt_rq->rt_time = 0; - rt_rq->rt_throttled = 0; - rt_rq->rt_runtime = 0; - raw_spin_lock_init(&rt_rq->rt_runtime_lock); -} - -#ifdef CONFIG_FAIR_GROUP_SCHED -static void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, - struct sched_entity *se, int cpu, - struct sched_entity *parent) -{ - struct rq *rq = cpu_rq(cpu); - - cfs_rq->tg = tg; - cfs_rq->rq = rq; -#ifdef CONFIG_SMP - /* allow initial update_cfs_load() to truncate */ - cfs_rq->load_stamp = 1; -#endif - init_cfs_rq_runtime(cfs_rq); - - tg->cfs_rq[cpu] = cfs_rq; - tg->se[cpu] = se; - - /* se could be NULL for root_task_group */ - if (!se) - return; - - if (!parent) - se->cfs_rq = &rq->cfs; - else - se->cfs_rq = parent->my_q; - - se->my_q = cfs_rq; - update_load_set(&se->load, 0); - se->parent = parent; -} +#ifdef CONFIG_CGROUP_SCHED +struct task_group root_task_group; #endif -#ifdef CONFIG_RT_GROUP_SCHED -static void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, - struct sched_rt_entity *rt_se, int cpu, - struct sched_rt_entity *parent) -{ - struct rq *rq = cpu_rq(cpu); - - rt_rq->highest_prio.curr = MAX_RT_PRIO; - rt_rq->rt_nr_boosted = 0; - rt_rq->rq = rq; - rt_rq->tg = tg; - - tg->rt_rq[cpu] = rt_rq; - tg->rt_se[cpu] = rt_se; - - if (!rt_se) - return; - - if (!parent) - rt_se->rt_rq = &rq->rt; - else - rt_se->rt_rq = parent->my_q; - - rt_se->my_q = rt_rq; - rt_se->parent = parent; - INIT_LIST_HEAD(&rt_se->run_list); -} -#endif +DECLARE_PER_CPU(cpumask_var_t, load_balance_tmpmask); void __init sched_init(void) { @@ -8249,9 +6866,17 @@ void __init sched_init(void) #ifdef CONFIG_CGROUP_SCHED list_add(&root_task_group.list, &task_groups); INIT_LIST_HEAD(&root_task_group.children); + INIT_LIST_HEAD(&root_task_group.siblings); autogroup_init(&init_task); + #endif /* CONFIG_CGROUP_SCHED */ +#ifdef CONFIG_CGROUP_CPUACCT + root_cpuacct.cpustat = &kernel_cpustat; + root_cpuacct.cpuusage = alloc_percpu(u64); + /* Too early, not expected to fail */ + BUG_ON(!root_cpuacct.cpuusage); +#endif for_each_possible_cpu(i) { struct rq *rq; @@ -8263,7 +6888,7 @@ void __init sched_init(void) init_cfs_rq(&rq->cfs); init_rt_rq(&rq->rt, rq); #ifdef CONFIG_FAIR_GROUP_SCHED - root_task_group.shares = root_task_group_load; + root_task_group.shares = ROOT_TASK_GROUP_LOAD; INIT_LIST_HEAD(&rq->leaf_cfs_rq_list); /* * How much cpu bandwidth does root_task_group get? @@ -8313,7 +6938,7 @@ void __init sched_init(void) rq->avg_idle = 2*sysctl_sched_migration_cost; rq_attach_root(rq, &def_root_domain); #ifdef CONFIG_NO_HZ - rq->nohz_balance_kick = 0; + rq->nohz_flags = 0; #endif #endif init_rq_hrtick(rq); @@ -8326,10 +6951,6 @@ void __init sched_init(void) INIT_HLIST_HEAD(&init_task.preempt_notifiers); #endif -#ifdef CONFIG_SMP - open_softirq(SCHED_SOFTIRQ, run_rebalance_domains); -#endif - #ifdef CONFIG_RT_MUTEXES plist_head_init(&init_task.pi_waiters); #endif @@ -8357,17 +6978,11 @@ void __init sched_init(void) #ifdef CONFIG_SMP zalloc_cpumask_var(&sched_domains_tmpmask, GFP_NOWAIT); -#ifdef CONFIG_NO_HZ - zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT); - alloc_cpumask_var(&nohz.grp_idle_mask, GFP_NOWAIT); - atomic_set(&nohz.load_balancer, nr_cpu_ids); - atomic_set(&nohz.first_pick_cpu, nr_cpu_ids); - atomic_set(&nohz.second_pick_cpu, nr_cpu_ids); -#endif /* May be allocated at isolcpus cmdline parse time */ if (cpu_isolated_map == NULL) zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT); -#endif /* SMP */ +#endif + init_sched_fair_class(); scheduler_running = 1; } @@ -8519,169 +7134,10 @@ void set_curr_task(int cpu, struct task_struct *p) #endif -#ifdef CONFIG_FAIR_GROUP_SCHED -static void free_fair_sched_group(struct task_group *tg) -{ - int i; - - destroy_cfs_bandwidth(tg_cfs_bandwidth(tg)); - - for_each_possible_cpu(i) { - if (tg->cfs_rq) - kfree(tg->cfs_rq[i]); - if (tg->se) - kfree(tg->se[i]); - } - - kfree(tg->cfs_rq); - kfree(tg->se); -} - -static -int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) -{ - struct cfs_rq *cfs_rq; - struct sched_entity *se; - int i; - - tg->cfs_rq = kzalloc(sizeof(cfs_rq) * nr_cpu_ids, GFP_KERNEL); - if (!tg->cfs_rq) - goto err; - tg->se = kzalloc(sizeof(se) * nr_cpu_ids, GFP_KERNEL); - if (!tg->se) - goto err; - - tg->shares = NICE_0_LOAD; - - init_cfs_bandwidth(tg_cfs_bandwidth(tg)); - - for_each_possible_cpu(i) { - cfs_rq = kzalloc_node(sizeof(struct cfs_rq), - GFP_KERNEL, cpu_to_node(i)); - if (!cfs_rq) - goto err; - - se = kzalloc_node(sizeof(struct sched_entity), - GFP_KERNEL, cpu_to_node(i)); - if (!se) - goto err_free_rq; - - init_cfs_rq(cfs_rq); - init_tg_cfs_entry(tg, cfs_rq, se, i, parent->se[i]); - } - - return 1; - -err_free_rq: - kfree(cfs_rq); -err: - return 0; -} - -static inline void unregister_fair_sched_group(struct task_group *tg, int cpu) -{ - struct rq *rq = cpu_rq(cpu); - unsigned long flags; - - /* - * Only empty task groups can be destroyed; so we can speculatively - * check on_list without danger of it being re-added. - */ - if (!tg->cfs_rq[cpu]->on_list) - return; - - raw_spin_lock_irqsave(&rq->lock, flags); - list_del_leaf_cfs_rq(tg->cfs_rq[cpu]); - raw_spin_unlock_irqrestore(&rq->lock, flags); -} -#else /* !CONFIG_FAIR_GROUP_SCHED */ -static inline void free_fair_sched_group(struct task_group *tg) -{ -} - -static inline -int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) -{ - return 1; -} - -static inline void unregister_fair_sched_group(struct task_group *tg, int cpu) -{ -} -#endif /* CONFIG_FAIR_GROUP_SCHED */ - -#ifdef CONFIG_RT_GROUP_SCHED -static void free_rt_sched_group(struct task_group *tg) -{ - int i; - - if (tg->rt_se) - destroy_rt_bandwidth(&tg->rt_bandwidth); - - for_each_possible_cpu(i) { - if (tg->rt_rq) - kfree(tg->rt_rq[i]); - if (tg->rt_se) - kfree(tg->rt_se[i]); - } - - kfree(tg->rt_rq); - kfree(tg->rt_se); -} - -static -int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent) -{ - struct rt_rq *rt_rq; - struct sched_rt_entity *rt_se; - int i; - - tg->rt_rq = kzalloc(sizeof(rt_rq) * nr_cpu_ids, GFP_KERNEL); - if (!tg->rt_rq) - goto err; - tg->rt_se = kzalloc(sizeof(rt_se) * nr_cpu_ids, GFP_KERNEL); - if (!tg->rt_se) - goto err; - - init_rt_bandwidth(&tg->rt_bandwidth, - ktime_to_ns(def_rt_bandwidth.rt_period), 0); - - for_each_possible_cpu(i) { - rt_rq = kzalloc_node(sizeof(struct rt_rq), - GFP_KERNEL, cpu_to_node(i)); - if (!rt_rq) - goto err; - - rt_se = kzalloc_node(sizeof(struct sched_rt_entity), - GFP_KERNEL, cpu_to_node(i)); - if (!rt_se) - goto err_free_rq; - - init_rt_rq(rt_rq, cpu_rq(i)); - rt_rq->rt_runtime = tg->rt_bandwidth.rt_runtime; - init_tg_rt_entry(tg, rt_rq, rt_se, i, parent->rt_se[i]); - } - - return 1; - -err_free_rq: - kfree(rt_rq); -err: - return 0; -} -#else /* !CONFIG_RT_GROUP_SCHED */ -static inline void free_rt_sched_group(struct task_group *tg) -{ -} - -static inline -int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent) -{ - return 1; -} -#endif /* CONFIG_RT_GROUP_SCHED */ - #ifdef CONFIG_CGROUP_SCHED +/* task_group_lock serializes the addition/removal of task groups */ +static DEFINE_SPINLOCK(task_group_lock); + static void free_sched_group(struct task_group *tg) { free_fair_sched_group(tg); @@ -8786,50 +7242,6 @@ void sched_move_task(struct task_struct *tsk) } #endif /* CONFIG_CGROUP_SCHED */ -#ifdef CONFIG_FAIR_GROUP_SCHED -static DEFINE_MUTEX(shares_mutex); - -int sched_group_set_shares(struct task_group *tg, unsigned long shares) -{ - int i; - unsigned long flags; - - /* - * We can't change the weight of the root cgroup. - */ - if (!tg->se[0]) - return -EINVAL; - - shares = clamp(shares, scale_load(MIN_SHARES), scale_load(MAX_SHARES)); - - mutex_lock(&shares_mutex); - if (tg->shares == shares) - goto done; - - tg->shares = shares; - for_each_possible_cpu(i) { - struct rq *rq = cpu_rq(i); - struct sched_entity *se; - - se = tg->se[i]; - /* Propagate contribution to hierarchy */ - raw_spin_lock_irqsave(&rq->lock, flags); - for_each_sched_entity(se) - update_cfs_shares(group_cfs_rq(se)); - raw_spin_unlock_irqrestore(&rq->lock, flags); - } - -done: - mutex_unlock(&shares_mutex); - return 0; -} - -unsigned long sched_group_shares(struct task_group *tg) -{ - return tg->shares; -} -#endif - #if defined(CONFIG_RT_GROUP_SCHED) || defined(CONFIG_CFS_BANDWIDTH) static unsigned long to_ratio(u64 period, u64 runtime) { @@ -8852,7 +7264,7 @@ static inline int tg_has_rt_tasks(struct task_group *tg) struct task_struct *g, *p; do_each_thread(g, p) { - if (rt_task(p) && rt_rq_of_se(&p->rt)->tg == tg) + if (rt_task(p) && task_rq(p)->rt.tg == tg) return 1; } while_each_thread(g, p); @@ -9144,24 +7556,31 @@ cpu_cgroup_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp) sched_destroy_group(tg); } -static int -cpu_cgroup_can_attach_task(struct cgroup *cgrp, struct task_struct *tsk) +static int cpu_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, + struct cgroup_taskset *tset) { + struct task_struct *task; + + cgroup_taskset_for_each(task, cgrp, tset) { #ifdef CONFIG_RT_GROUP_SCHED - if (!sched_rt_can_attach(cgroup_tg(cgrp), tsk)) - return -EINVAL; + if (!sched_rt_can_attach(cgroup_tg(cgrp), task)) + return -EINVAL; #else - /* We don't support RT-tasks being in separate groups */ - if (tsk->sched_class != &fair_sched_class) - return -EINVAL; + /* We don't support RT-tasks being in separate groups */ + if (task->sched_class != &fair_sched_class) + return -EINVAL; #endif + } return 0; } -static void -cpu_cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk) +static void cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, + struct cgroup_taskset *tset) { - sched_move_task(tsk); + struct task_struct *task; + + cgroup_taskset_for_each(task, cgrp, tset) + sched_move_task(task); } static void @@ -9203,8 +7622,8 @@ static int __cfs_schedulable(struct task_group *tg, u64 period, u64 runtime); static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota) { - int i, ret = 0, runtime_enabled; - struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(tg); + int i, ret = 0, runtime_enabled, runtime_was_enabled; + struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth; if (tg == &root_task_group) return -EINVAL; @@ -9231,6 +7650,8 @@ static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota) goto out_unlock; runtime_enabled = quota != RUNTIME_INF; + runtime_was_enabled = cfs_b->quota != RUNTIME_INF; + account_cfs_bandwidth_used(runtime_enabled, runtime_was_enabled); raw_spin_lock_irq(&cfs_b->lock); cfs_b->period = ns_to_ktime(period); cfs_b->quota = quota; @@ -9246,13 +7667,13 @@ static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota) for_each_possible_cpu(i) { struct cfs_rq *cfs_rq = tg->cfs_rq[i]; - struct rq *rq = rq_of(cfs_rq); + struct rq *rq = cfs_rq->rq; raw_spin_lock_irq(&rq->lock); cfs_rq->runtime_enabled = runtime_enabled; cfs_rq->runtime_remaining = 0; - if (cfs_rq_throttled(cfs_rq)) + if (cfs_rq->throttled) unthrottle_cfs_rq(cfs_rq); raw_spin_unlock_irq(&rq->lock); } @@ -9266,7 +7687,7 @@ int tg_set_cfs_quota(struct task_group *tg, long cfs_quota_us) { u64 quota, period; - period = ktime_to_ns(tg_cfs_bandwidth(tg)->period); + period = ktime_to_ns(tg->cfs_bandwidth.period); if (cfs_quota_us < 0) quota = RUNTIME_INF; else @@ -9279,10 +7700,10 @@ long tg_get_cfs_quota(struct task_group *tg) { u64 quota_us; - if (tg_cfs_bandwidth(tg)->quota == RUNTIME_INF) + if (tg->cfs_bandwidth.quota == RUNTIME_INF) return -1; - quota_us = tg_cfs_bandwidth(tg)->quota; + quota_us = tg->cfs_bandwidth.quota; do_div(quota_us, NSEC_PER_USEC); return quota_us; @@ -9293,10 +7714,7 @@ int tg_set_cfs_period(struct task_group *tg, long cfs_period_us) u64 quota, period; period = (u64)cfs_period_us * NSEC_PER_USEC; - quota = tg_cfs_bandwidth(tg)->quota; - - if (period <= 0) - return -EINVAL; + quota = tg->cfs_bandwidth.quota; return tg_set_cfs_bandwidth(tg, period, quota); } @@ -9305,7 +7723,7 @@ long tg_get_cfs_period(struct task_group *tg) { u64 cfs_period_us; - cfs_period_us = ktime_to_ns(tg_cfs_bandwidth(tg)->period); + cfs_period_us = ktime_to_ns(tg->cfs_bandwidth.period); do_div(cfs_period_us, NSEC_PER_USEC); return cfs_period_us; @@ -9365,13 +7783,13 @@ static u64 normalize_cfs_quota(struct task_group *tg, static int tg_cfs_schedulable_down(struct task_group *tg, void *data) { struct cfs_schedulable_data *d = data; - struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(tg); + struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth; s64 quota = 0, parent_quota = -1; if (!tg->parent) { quota = RUNTIME_INF; } else { - struct cfs_bandwidth *parent_b = tg_cfs_bandwidth(tg->parent); + struct cfs_bandwidth *parent_b = &tg->parent->cfs_bandwidth; quota = normalize_cfs_quota(tg, d); parent_quota = parent_b->hierarchal_quota; @@ -9415,7 +7833,7 @@ static int cpu_stats_show(struct cgroup *cgrp, struct cftype *cft, struct cgroup_map_cb *cb) { struct task_group *tg = cgroup_tg(cgrp); - struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(tg); + struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth; cb->fill(cb, "nr_periods", cfs_b->nr_periods); cb->fill(cb, "nr_throttled", cfs_b->nr_throttled); @@ -9497,8 +7915,8 @@ struct cgroup_subsys cpu_cgroup_subsys = { .name = "cpu", .create = cpu_cgroup_create, .destroy = cpu_cgroup_destroy, - .can_attach_task = cpu_cgroup_can_attach_task, - .attach_task = cpu_cgroup_attach_task, + .can_attach = cpu_cgroup_can_attach, + .attach = cpu_cgroup_attach, .exit = cpu_cgroup_exit, .populate = cpu_cgroup_populate, .subsys_id = cpu_cgroup_subsys_id, @@ -9516,38 +7934,16 @@ struct cgroup_subsys cpu_cgroup_subsys = { * (balbir@in.ibm.com). */ -/* track cpu usage of a group of tasks and its child groups */ -struct cpuacct { - struct cgroup_subsys_state css; - /* cpuusage holds pointer to a u64-type object on every cpu */ - u64 __percpu *cpuusage; - struct percpu_counter cpustat[CPUACCT_STAT_NSTATS]; - struct cpuacct *parent; -}; - -struct cgroup_subsys cpuacct_subsys; - -/* return cpu accounting group corresponding to this container */ -static inline struct cpuacct *cgroup_ca(struct cgroup *cgrp) -{ - return container_of(cgroup_subsys_state(cgrp, cpuacct_subsys_id), - struct cpuacct, css); -} - -/* return cpu accounting group to which this task belongs */ -static inline struct cpuacct *task_ca(struct task_struct *tsk) -{ - return container_of(task_subsys_state(tsk, cpuacct_subsys_id), - struct cpuacct, css); -} - /* create a new cpu accounting group */ static struct cgroup_subsys_state *cpuacct_create( struct cgroup_subsys *ss, struct cgroup *cgrp) { - struct cpuacct *ca = kzalloc(sizeof(*ca), GFP_KERNEL); - int i; + struct cpuacct *ca; + + if (!cgrp->parent) + return &root_cpuacct.css; + ca = kzalloc(sizeof(*ca), GFP_KERNEL); if (!ca) goto out; @@ -9555,18 +7951,13 @@ static struct cgroup_subsys_state *cpuacct_create( if (!ca->cpuusage) goto out_free_ca; - for (i = 0; i < CPUACCT_STAT_NSTATS; i++) - if (percpu_counter_init(&ca->cpustat[i], 0)) - goto out_free_counters; - - if (cgrp->parent) - ca->parent = cgroup_ca(cgrp->parent); + ca->cpustat = alloc_percpu(struct kernel_cpustat); + if (!ca->cpustat) + goto out_free_cpuusage; return &ca->css; -out_free_counters: - while (--i >= 0) - percpu_counter_destroy(&ca->cpustat[i]); +out_free_cpuusage: free_percpu(ca->cpuusage); out_free_ca: kfree(ca); @@ -9579,10 +7970,8 @@ static void cpuacct_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp) { struct cpuacct *ca = cgroup_ca(cgrp); - int i; - for (i = 0; i < CPUACCT_STAT_NSTATS; i++) - percpu_counter_destroy(&ca->cpustat[i]); + free_percpu(ca->cpustat); free_percpu(ca->cpuusage); kfree(ca); } @@ -9675,16 +8064,31 @@ static const char *cpuacct_stat_desc[] = { }; static int cpuacct_stats_show(struct cgroup *cgrp, struct cftype *cft, - struct cgroup_map_cb *cb) + struct cgroup_map_cb *cb) { struct cpuacct *ca = cgroup_ca(cgrp); - int i; + int cpu; + s64 val = 0; - for (i = 0; i < CPUACCT_STAT_NSTATS; i++) { - s64 val = percpu_counter_read(&ca->cpustat[i]); - val = cputime64_to_clock_t(val); - cb->fill(cb, cpuacct_stat_desc[i], val); + for_each_online_cpu(cpu) { + struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu); + val += kcpustat->cpustat[CPUTIME_USER]; + val += kcpustat->cpustat[CPUTIME_NICE]; } + val = cputime64_to_clock_t(val); + cb->fill(cb, cpuacct_stat_desc[CPUACCT_STAT_USER], val); + + val = 0; + for_each_online_cpu(cpu) { + struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu); + val += kcpustat->cpustat[CPUTIME_SYSTEM]; + val += kcpustat->cpustat[CPUTIME_IRQ]; + val += kcpustat->cpustat[CPUTIME_SOFTIRQ]; + } + + val = cputime64_to_clock_t(val); + cb->fill(cb, cpuacct_stat_desc[CPUACCT_STAT_SYSTEM], val); + return 0; } @@ -9714,7 +8118,7 @@ static int cpuacct_populate(struct cgroup_subsys *ss, struct cgroup *cgrp) * * called with rq->lock held. */ -static void cpuacct_charge(struct task_struct *tsk, u64 cputime) +void cpuacct_charge(struct task_struct *tsk, u64 cputime) { struct cpuacct *ca; int cpu; @@ -9728,7 +8132,7 @@ static void cpuacct_charge(struct task_struct *tsk, u64 cputime) ca = task_ca(tsk); - for (; ca; ca = ca->parent) { + for (; ca; ca = parent_ca(ca)) { u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); *cpuusage += cputime; } @@ -9736,45 +8140,6 @@ static void cpuacct_charge(struct task_struct *tsk, u64 cputime) rcu_read_unlock(); } -/* - * When CONFIG_VIRT_CPU_ACCOUNTING is enabled one jiffy can be very large - * in cputime_t units. As a result, cpuacct_update_stats calls - * percpu_counter_add with values large enough to always overflow the - * per cpu batch limit causing bad SMP scalability. - * - * To fix this we scale percpu_counter_batch by cputime_one_jiffy so we - * batch the same amount of time with CONFIG_VIRT_CPU_ACCOUNTING disabled - * and enabled. We cap it at INT_MAX which is the largest allowed batch value. - */ -#ifdef CONFIG_SMP -#define CPUACCT_BATCH \ - min_t(long, percpu_counter_batch * cputime_one_jiffy, INT_MAX) -#else -#define CPUACCT_BATCH 0 -#endif - -/* - * Charge the system/user time to the task's accounting group. - */ -static void cpuacct_update_stats(struct task_struct *tsk, - enum cpuacct_stat_index idx, cputime_t val) -{ - struct cpuacct *ca; - int batch = CPUACCT_BATCH; - - if (unlikely(!cpuacct_subsys.active)) - return; - - rcu_read_lock(); - ca = task_ca(tsk); - - do { - __percpu_counter_add(&ca->cpustat[idx], val, batch); - ca = ca->parent; - } while (ca); - rcu_read_unlock(); -} - struct cgroup_subsys cpuacct_subsys = { .name = "cpuacct", .create = cpuacct_create, diff --git a/kernel/sched_cpupri.c b/kernel/sched/cpupri.c index a86cf9d..b0d798e 100644 --- a/kernel/sched_cpupri.c +++ b/kernel/sched/cpupri.c @@ -1,5 +1,5 @@ /* - * kernel/sched_cpupri.c + * kernel/sched/cpupri.c * * CPU priority management * @@ -28,7 +28,7 @@ */ #include <linux/gfp.h> -#include "sched_cpupri.h" +#include "cpupri.h" /* Convert between a 140 based task->prio, and our 102 based cpupri */ static int convert_prio(int prio) diff --git a/kernel/sched_cpupri.h b/kernel/sched/cpupri.h index f6d7561..f6d7561 100644 --- a/kernel/sched_cpupri.h +++ b/kernel/sched/cpupri.h diff --git a/kernel/sched_debug.c b/kernel/sched/debug.c index a6710a1..2a075e1 100644 --- a/kernel/sched_debug.c +++ b/kernel/sched/debug.c @@ -1,5 +1,5 @@ /* - * kernel/time/sched_debug.c + * kernel/sched/debug.c * * Print the CFS rbtree * @@ -16,6 +16,8 @@ #include <linux/kallsyms.h> #include <linux/utsname.h> +#include "sched.h" + static DEFINE_SPINLOCK(sched_debug_lock); /* @@ -373,7 +375,7 @@ static int sched_debug_show(struct seq_file *m, void *v) return 0; } -static void sysrq_sched_debug_show(void) +void sysrq_sched_debug_show(void) { sched_debug_show(NULL, NULL); } diff --git a/kernel/sched_fair.c b/kernel/sched/fair.c index 8a39fa3..84adb2d 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched/fair.c @@ -23,6 +23,13 @@ #include <linux/latencytop.h> #include <linux/sched.h> #include <linux/cpumask.h> +#include <linux/slab.h> +#include <linux/profile.h> +#include <linux/interrupt.h> + +#include <trace/events/sched.h> + +#include "sched.h" /* * Targeted preemption latency for CPU-bound tasks: @@ -103,7 +110,110 @@ unsigned int __read_mostly sysctl_sched_shares_window = 10000000UL; unsigned int sysctl_sched_cfs_bandwidth_slice = 5000UL; #endif -static const struct sched_class fair_sched_class; +/* + * Increase the granularity value when there are more CPUs, + * because with more CPUs the 'effective latency' as visible + * to users decreases. But the relationship is not linear, + * so pick a second-best guess by going with the log2 of the + * number of CPUs. + * + * This idea comes from the SD scheduler of Con Kolivas: + */ +static int get_update_sysctl_factor(void) +{ + unsigned int cpus = min_t(int, num_online_cpus(), 8); + unsigned int factor; + + switch (sysctl_sched_tunable_scaling) { + case SCHED_TUNABLESCALING_NONE: + factor = 1; + break; + case SCHED_TUNABLESCALING_LINEAR: + factor = cpus; + break; + case SCHED_TUNABLESCALING_LOG: + default: + factor = 1 + ilog2(cpus); + break; + } + + return factor; +} + +static void update_sysctl(void) +{ + unsigned int factor = get_update_sysctl_factor(); + +#define SET_SYSCTL(name) \ + (sysctl_##name = (factor) * normalized_sysctl_##name) + SET_SYSCTL(sched_min_granularity); + SET_SYSCTL(sched_latency); + SET_SYSCTL(sched_wakeup_granularity); +#undef SET_SYSCTL +} + +void sched_init_granularity(void) +{ + update_sysctl(); +} + +#if BITS_PER_LONG == 32 +# define WMULT_CONST (~0UL) +#else +# define WMULT_CONST (1UL << 32) +#endif + +#define WMULT_SHIFT 32 + +/* + * Shift right and round: + */ +#define SRR(x, y) (((x) + (1UL << ((y) - 1))) >> (y)) + +/* + * delta *= weight / lw + */ +static unsigned long +calc_delta_mine(unsigned long delta_exec, unsigned long weight, + struct load_weight *lw) +{ + u64 tmp; + + /* + * weight can be less than 2^SCHED_LOAD_RESOLUTION for task group sched + * entities since MIN_SHARES = 2. Treat weight as 1 if less than + * 2^SCHED_LOAD_RESOLUTION. + */ + if (likely(weight > (1UL << SCHED_LOAD_RESOLUTION))) + tmp = (u64)delta_exec * scale_load_down(weight); + else + tmp = (u64)delta_exec; + + if (!lw->inv_weight) { + unsigned long w = scale_load_down(lw->weight); + + if (BITS_PER_LONG > 32 && unlikely(w >= WMULT_CONST)) + lw->inv_weight = 1; + else if (unlikely(!w)) + lw->inv_weight = WMULT_CONST; + else + lw->inv_weight = WMULT_CONST / w; + } + + /* + * Check whether we'd overflow the 64-bit multiplication: + */ + if (unlikely(tmp > WMULT_CONST)) + tmp = SRR(SRR(tmp, WMULT_SHIFT/2) * lw->inv_weight, + WMULT_SHIFT/2); + else + tmp = SRR(tmp * lw->inv_weight, WMULT_SHIFT); + + return (unsigned long)min(tmp, (u64)(unsigned long)LONG_MAX); +} + + +const struct sched_class fair_sched_class; /************************************************************** * CFS operations on generic schedulable entities: @@ -413,7 +523,7 @@ static void __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) rb_erase(&se->run_node, &cfs_rq->tasks_timeline); } -static struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq) +struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq) { struct rb_node *left = cfs_rq->rb_leftmost; @@ -434,7 +544,7 @@ static struct sched_entity *__pick_next_entity(struct sched_entity *se) } #ifdef CONFIG_SCHED_DEBUG -static struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq) +struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq) { struct rb_node *last = rb_last(&cfs_rq->tasks_timeline); @@ -684,7 +794,7 @@ account_entity_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se) { update_load_add(&cfs_rq->load, se->load.weight); if (!parent_entity(se)) - inc_cpu_load(rq_of(cfs_rq), se->load.weight); + update_load_add(&rq_of(cfs_rq)->load, se->load.weight); if (entity_is_task(se)) { add_cfs_task_weight(cfs_rq, se->load.weight); list_add(&se->group_node, &cfs_rq->tasks); @@ -697,7 +807,7 @@ account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se) { update_load_sub(&cfs_rq->load, se->load.weight); if (!parent_entity(se)) - dec_cpu_load(rq_of(cfs_rq), se->load.weight); + update_load_sub(&rq_of(cfs_rq)->load, se->load.weight); if (entity_is_task(se)) { add_cfs_task_weight(cfs_rq, -se->load.weight); list_del_init(&se->group_node); @@ -893,7 +1003,6 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se) if (unlikely(delta > se->statistics.sleep_max)) se->statistics.sleep_max = delta; - se->statistics.sleep_start = 0; se->statistics.sum_sleep_runtime += delta; if (tsk) { @@ -910,7 +1019,6 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se) if (unlikely(delta > se->statistics.block_max)) se->statistics.block_max = delta; - se->statistics.block_start = 0; se->statistics.sum_sleep_runtime += delta; if (tsk) { @@ -920,6 +1028,8 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se) trace_sched_stat_iowait(tsk, delta); } + trace_sched_stat_blocked(tsk, delta); + /* * Blocking time is in units of nanosecs, so shift by * 20 to get a milliseconds-range estimation of the @@ -1287,6 +1397,32 @@ entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued) */ #ifdef CONFIG_CFS_BANDWIDTH + +#ifdef HAVE_JUMP_LABEL +static struct jump_label_key __cfs_bandwidth_used; + +static inline bool cfs_bandwidth_used(void) +{ + return static_branch(&__cfs_bandwidth_used); +} + +void account_cfs_bandwidth_used(int enabled, int was_enabled) +{ + /* only need to count groups transitioning between enabled/!enabled */ + if (enabled && !was_enabled) + jump_label_inc(&__cfs_bandwidth_used); + else if (!enabled && was_enabled) + jump_label_dec(&__cfs_bandwidth_used); +} +#else /* HAVE_JUMP_LABEL */ +static bool cfs_bandwidth_used(void) +{ + return true; +} + +void account_cfs_bandwidth_used(int enabled, int was_enabled) {} +#endif /* HAVE_JUMP_LABEL */ + /* * default period for cfs group bandwidth. * default: 0.1s, units: nanoseconds @@ -1308,7 +1444,7 @@ static inline u64 sched_cfs_bandwidth_slice(void) * * requires cfs_b->lock */ -static void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b) +void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b) { u64 now; @@ -1320,6 +1456,11 @@ static void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b) cfs_b->runtime_expires = now + ktime_to_ns(cfs_b->period); } +static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg) +{ + return &tg->cfs_bandwidth; +} + /* returns 0 on failure to allocate runtime */ static int assign_cfs_rq_runtime(struct cfs_rq *cfs_rq) { @@ -1421,7 +1562,7 @@ static void __account_cfs_rq_runtime(struct cfs_rq *cfs_rq, static __always_inline void account_cfs_rq_runtime(struct cfs_rq *cfs_rq, unsigned long delta_exec) { - if (!cfs_rq->runtime_enabled) + if (!cfs_bandwidth_used() || !cfs_rq->runtime_enabled) return; __account_cfs_rq_runtime(cfs_rq, delta_exec); @@ -1429,13 +1570,13 @@ static __always_inline void account_cfs_rq_runtime(struct cfs_rq *cfs_rq, static inline int cfs_rq_throttled(struct cfs_rq *cfs_rq) { - return cfs_rq->throttled; + return cfs_bandwidth_used() && cfs_rq->throttled; } /* check whether cfs_rq, or any parent, is throttled */ static inline int throttled_hierarchy(struct cfs_rq *cfs_rq) { - return cfs_rq->throttle_count; + return cfs_bandwidth_used() && cfs_rq->throttle_count; } /* @@ -1530,7 +1671,7 @@ static void throttle_cfs_rq(struct cfs_rq *cfs_rq) raw_spin_unlock(&cfs_b->lock); } -static void unthrottle_cfs_rq(struct cfs_rq *cfs_rq) +void unthrottle_cfs_rq(struct cfs_rq *cfs_rq) { struct rq *rq = rq_of(cfs_rq); struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg); @@ -1756,6 +1897,9 @@ static void __return_cfs_rq_runtime(struct cfs_rq *cfs_rq) static __always_inline void return_cfs_rq_runtime(struct cfs_rq *cfs_rq) { + if (!cfs_bandwidth_used()) + return; + if (!cfs_rq->runtime_enabled || cfs_rq->nr_running) return; @@ -1801,6 +1945,9 @@ static void do_sched_cfs_slack_timer(struct cfs_bandwidth *cfs_b) */ static void check_enqueue_throttle(struct cfs_rq *cfs_rq) { + if (!cfs_bandwidth_used()) + return; + /* an active group must be handled by the update_curr()->put() path */ if (!cfs_rq->runtime_enabled || cfs_rq->curr) return; @@ -1818,6 +1965,9 @@ static void check_enqueue_throttle(struct cfs_rq *cfs_rq) /* conditionally throttle active cfs_rq's from put_prev_entity() */ static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq) { + if (!cfs_bandwidth_used()) + return; + if (likely(!cfs_rq->runtime_enabled || cfs_rq->runtime_remaining > 0)) return; @@ -1830,7 +1980,112 @@ static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq) throttle_cfs_rq(cfs_rq); } -#else + +static inline u64 default_cfs_period(void); +static int do_sched_cfs_period_timer(struct cfs_bandwidth *cfs_b, int overrun); +static void do_sched_cfs_slack_timer(struct cfs_bandwidth *cfs_b); + +static enum hrtimer_restart sched_cfs_slack_timer(struct hrtimer *timer) +{ + struct cfs_bandwidth *cfs_b = + container_of(timer, struct cfs_bandwidth, slack_timer); + do_sched_cfs_slack_timer(cfs_b); + + return HRTIMER_NORESTART; +} + +static enum hrtimer_restart sched_cfs_period_timer(struct hrtimer *timer) +{ + struct cfs_bandwidth *cfs_b = + container_of(timer, struct cfs_bandwidth, period_timer); + ktime_t now; + int overrun; + int idle = 0; + + for (;;) { + now = hrtimer_cb_get_time(timer); + overrun = hrtimer_forward(timer, now, cfs_b->period); + + if (!overrun) + break; + + idle = do_sched_cfs_period_timer(cfs_b, overrun); + } + + return idle ? HRTIMER_NORESTART : HRTIMER_RESTART; +} + +void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b) +{ + raw_spin_lock_init(&cfs_b->lock); + cfs_b->runtime = 0; + cfs_b->quota = RUNTIME_INF; + cfs_b->period = ns_to_ktime(default_cfs_period()); + + INIT_LIST_HEAD(&cfs_b->throttled_cfs_rq); + hrtimer_init(&cfs_b->period_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + cfs_b->period_timer.function = sched_cfs_period_timer; + hrtimer_init(&cfs_b->slack_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + cfs_b->slack_timer.function = sched_cfs_slack_timer; +} + +static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq) +{ + cfs_rq->runtime_enabled = 0; + INIT_LIST_HEAD(&cfs_rq->throttled_list); +} + +/* requires cfs_b->lock, may release to reprogram timer */ +void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b) +{ + /* + * The timer may be active because we're trying to set a new bandwidth + * period or because we're racing with the tear-down path + * (timer_active==0 becomes visible before the hrtimer call-back + * terminates). In either case we ensure that it's re-programmed + */ + while (unlikely(hrtimer_active(&cfs_b->period_timer))) { + raw_spin_unlock(&cfs_b->lock); + /* ensure cfs_b->lock is available while we wait */ + hrtimer_cancel(&cfs_b->period_timer); + + raw_spin_lock(&cfs_b->lock); + /* if someone else restarted the timer then we're done */ + if (cfs_b->timer_active) + return; + } + + cfs_b->timer_active = 1; + start_bandwidth_timer(&cfs_b->period_timer, cfs_b->period); +} + +static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b) +{ + hrtimer_cancel(&cfs_b->period_timer); + hrtimer_cancel(&cfs_b->slack_timer); +} + +void unthrottle_offline_cfs_rqs(struct rq *rq) +{ + struct cfs_rq *cfs_rq; + + for_each_leaf_cfs_rq(rq, cfs_rq) { + struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg); + + if (!cfs_rq->runtime_enabled) + continue; + + /* + * clock_task is not advancing so we just need to make sure + * there's some valid quota amount + */ + cfs_rq->runtime_remaining = cfs_b->quota; + if (cfs_rq_throttled(cfs_rq)) + unthrottle_cfs_rq(cfs_rq); + } +} + +#else /* CONFIG_CFS_BANDWIDTH */ static void account_cfs_rq_runtime(struct cfs_rq *cfs_rq, unsigned long delta_exec) {} static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq) {} @@ -1852,8 +2107,22 @@ static inline int throttled_lb_pair(struct task_group *tg, { return 0; } + +void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {} + +#ifdef CONFIG_FAIR_GROUP_SCHED +static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq) {} #endif +static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg) +{ + return NULL; +} +static inline void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {} +void unthrottle_offline_cfs_rqs(struct rq *rq) {} + +#endif /* CONFIG_CFS_BANDWIDTH */ + /************************************************** * CFS operations on tasks: */ @@ -1866,7 +2135,7 @@ static void hrtick_start_fair(struct rq *rq, struct task_struct *p) WARN_ON(task_rq(p) != rq); - if (hrtick_enabled(rq) && cfs_rq->nr_running > 1) { + if (cfs_rq->nr_running > 1) { u64 slice = sched_slice(cfs_rq, se); u64 ran = se->sum_exec_runtime - se->prev_sum_exec_runtime; s64 delta = slice - ran; @@ -1897,7 +2166,7 @@ static void hrtick_update(struct rq *rq) { struct task_struct *curr = rq->curr; - if (curr->sched_class != &fair_sched_class) + if (!hrtick_enabled(rq) || curr->sched_class != &fair_sched_class) return; if (cfs_rq_of(&curr->se)->nr_running < sched_nr_latency) @@ -2020,6 +2289,61 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags) } #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; +} + +/* + * 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 unsigned long power_of(int cpu) +{ + return cpu_rq(cpu)->cpu_power; +} + +static unsigned long cpu_avg_load_per_task(int cpu) +{ + struct rq *rq = cpu_rq(cpu); + unsigned long nr_running = ACCESS_ONCE(rq->nr_running); + + if (nr_running) + return rq->load.weight / nr_running; + + return 0; +} + static void task_waking_fair(struct task_struct *p) { @@ -2327,7 +2651,7 @@ static int select_idle_sibling(struct task_struct *p, int target) int prev_cpu = task_cpu(p); struct sched_domain *sd; struct sched_group *sg; - int i, smt = 0; + int i; /* * If the task is going to be woken-up on this cpu and if it is @@ -2347,17 +2671,9 @@ static int select_idle_sibling(struct task_struct *p, int target) * Otherwise, iterate the domains and find an elegible idle cpu. */ rcu_read_lock(); -again: - for_each_domain(target, sd) { - if (!smt && (sd->flags & SD_SHARE_CPUPOWER)) - continue; - - if (smt && !(sd->flags & SD_SHARE_CPUPOWER)) - break; - - if (!(sd->flags & SD_SHARE_PKG_RESOURCES)) - break; + sd = rcu_dereference(per_cpu(sd_llc, target)); + for_each_lower_domain(sd) { sg = sd->groups; do { if (!cpumask_intersects(sched_group_cpus(sg), @@ -2376,10 +2692,6 @@ next: sg = sg->next; } while (sg != sd->groups); } - if (!smt) { - smt = 1; - goto again; - } done: rcu_read_unlock(); @@ -2408,6 +2720,9 @@ select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flags) int want_sd = 1; int sync = wake_flags & WF_SYNC; + if (p->rt.nr_cpus_allowed == 1) + return prev_cpu; + if (sd_flag & SD_BALANCE_WAKE) { if (cpumask_test_cpu(cpu, tsk_cpus_allowed(p))) want_affine = 1; @@ -2692,7 +3007,8 @@ static struct task_struct *pick_next_task_fair(struct rq *rq) } while (cfs_rq); p = task_of(se); - hrtick_start_fair(rq, p); + if (hrtick_enabled(rq)) + hrtick_start_fair(rq, p); return p; } @@ -2736,6 +3052,12 @@ static void yield_task_fair(struct rq *rq) * Update run-time statistics of the 'current'. */ update_curr(cfs_rq); + /* + * Tell update_rq_clock() that we've just updated, + * so we don't do microscopic update in schedule() + * and double the fastpath cost. + */ + rq->skip_clock_update = 1; } set_skip_buddy(se); @@ -2776,12 +3098,50 @@ static void pull_task(struct rq *src_rq, struct task_struct *p, } /* + * Is this task likely cache-hot: + */ +static int +task_hot(struct task_struct *p, u64 now, struct sched_domain *sd) +{ + s64 delta; + + if (p->sched_class != &fair_sched_class) + return 0; + + if (unlikely(p->policy == SCHED_IDLE)) + return 0; + + /* + * Buddy candidates are cache hot: + */ + if (sched_feat(CACHE_HOT_BUDDY) && this_rq()->nr_running && + (&p->se == cfs_rq_of(&p->se)->next || + &p->se == cfs_rq_of(&p->se)->last)) + return 1; + + if (sysctl_sched_migration_cost == -1) + return 1; + if (sysctl_sched_migration_cost == 0) + return 0; + + delta = now - p->se.exec_start; + + return delta < (s64)sysctl_sched_migration_cost; +} + +#define LBF_ALL_PINNED 0x01 +#define LBF_NEED_BREAK 0x02 /* clears into HAD_BREAK */ +#define LBF_HAD_BREAK 0x04 +#define LBF_HAD_BREAKS 0x0C /* count HAD_BREAKs overflows into ABORT */ +#define LBF_ABORT 0x10 + +/* * can_migrate_task - may task p from runqueue rq be migrated to this_cpu? */ static int can_migrate_task(struct task_struct *p, struct rq *rq, int this_cpu, struct sched_domain *sd, enum cpu_idle_type idle, - int *all_pinned) + int *lb_flags) { int tsk_cache_hot = 0; /* @@ -2794,7 +3154,7 @@ int can_migrate_task(struct task_struct *p, struct rq *rq, int this_cpu, schedstat_inc(p, se.statistics.nr_failed_migrations_affine); return 0; } - *all_pinned = 0; + *lb_flags &= ~LBF_ALL_PINNED; if (task_running(rq, p)) { schedstat_inc(p, se.statistics.nr_failed_migrations_running); @@ -2868,7 +3228,7 @@ move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest, static unsigned long balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_load_move, struct sched_domain *sd, - enum cpu_idle_type idle, int *all_pinned, + enum cpu_idle_type idle, int *lb_flags, struct cfs_rq *busiest_cfs_rq) { int loops = 0, pulled = 0; @@ -2879,12 +3239,14 @@ balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, goto out; list_for_each_entry_safe(p, n, &busiest_cfs_rq->tasks, se.group_node) { - if (loops++ > sysctl_sched_nr_migrate) + if (loops++ > sysctl_sched_nr_migrate) { + *lb_flags |= LBF_NEED_BREAK; break; + } if ((p->se.load.weight >> 1) > rem_load_move || !can_migrate_task(p, busiest, this_cpu, sd, idle, - all_pinned)) + lb_flags)) continue; pull_task(busiest, p, this_rq, this_cpu); @@ -2897,8 +3259,10 @@ balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, * kernels will stop after the first task is pulled to minimize * the critical section. */ - if (idle == CPU_NEWLY_IDLE) + if (idle == CPU_NEWLY_IDLE) { + *lb_flags |= LBF_ABORT; break; + } #endif /* @@ -3003,7 +3367,7 @@ static unsigned long load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, - int *all_pinned) + int *lb_flags) { long rem_load_move = max_load_move; struct cfs_rq *busiest_cfs_rq; @@ -3016,6 +3380,9 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long busiest_weight = busiest_cfs_rq->load.weight; u64 rem_load, moved_load; + if (*lb_flags & (LBF_NEED_BREAK|LBF_ABORT)) + break; + /* * empty group or part of a throttled hierarchy */ @@ -3027,7 +3394,7 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, rem_load = div_u64(rem_load, busiest_h_load + 1); moved_load = balance_tasks(this_rq, this_cpu, busiest, - rem_load, sd, idle, all_pinned, + rem_load, sd, idle, lb_flags, busiest_cfs_rq); if (!moved_load) @@ -3053,10 +3420,10 @@ static unsigned long load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, - int *all_pinned) + int *lb_flags) { return balance_tasks(this_rq, this_cpu, busiest, - max_load_move, sd, idle, all_pinned, + max_load_move, sd, idle, lb_flags, &busiest->cfs); } #endif @@ -3071,29 +3438,30 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, static int move_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, - int *all_pinned) + int *lb_flags) { unsigned long total_load_moved = 0, load_moved; do { load_moved = load_balance_fair(this_rq, this_cpu, busiest, max_load_move - total_load_moved, - sd, idle, all_pinned); + sd, idle, lb_flags); total_load_moved += load_moved; + if (*lb_flags & (LBF_NEED_BREAK|LBF_ABORT)) + break; + #ifdef CONFIG_PREEMPT /* * NEWIDLE balancing is a source of latency, so preemptible * kernels will stop after the first task is pulled to minimize * the critical section. */ - if (idle == CPU_NEWLY_IDLE && this_rq->nr_running) - break; - - if (raw_spin_is_contended(&this_rq->lock) || - raw_spin_is_contended(&busiest->lock)) + if (idle == CPU_NEWLY_IDLE && this_rq->nr_running) { + *lb_flags |= LBF_ABORT; break; + } #endif } while (load_moved && max_load_move > total_load_moved); @@ -3155,15 +3523,6 @@ struct sg_lb_stats { }; /** - * group_first_cpu - Returns the first cpu in the cpumask of a sched_group. - * @group: The group whose first cpu is to be returned. - */ -static inline unsigned int group_first_cpu(struct sched_group *group) -{ - return cpumask_first(sched_group_cpus(group)); -} - -/** * get_sd_load_idx - Obtain the load index for a given sched domain. * @sd: The sched_domain whose load_idx is to be obtained. * @idle: The Idle status of the CPU for whose sd load_icx is obtained. @@ -3412,7 +3771,7 @@ static void update_cpu_power(struct sched_domain *sd, int cpu) sdg->sgp->power = power; } -static void update_group_power(struct sched_domain *sd, int cpu) +void update_group_power(struct sched_domain *sd, int cpu) { struct sched_domain *child = sd->child; struct sched_group *group, *sdg = sd->groups; @@ -3678,11 +4037,6 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu, } while (sg != sd->groups); } -int __weak arch_sd_sibling_asym_packing(void) -{ - return 0*SD_ASYM_PACKING; -} - /** * check_asym_packing - Check to see if the group is packed into the * sched doman. @@ -4046,7 +4400,7 @@ find_busiest_queue(struct sched_domain *sd, struct sched_group *group, #define MAX_PINNED_INTERVAL 512 /* Working cpumask for load_balance and load_balance_newidle. */ -static DEFINE_PER_CPU(cpumask_var_t, load_balance_tmpmask); +DEFINE_PER_CPU(cpumask_var_t, load_balance_tmpmask); static int need_active_balance(struct sched_domain *sd, int idle, int busiest_cpu, int this_cpu) @@ -4097,7 +4451,7 @@ static int load_balance(int this_cpu, struct rq *this_rq, struct sched_domain *sd, enum cpu_idle_type idle, int *balance) { - int ld_moved, all_pinned = 0, active_balance = 0; + int ld_moved, lb_flags = 0, active_balance = 0; struct sched_group *group; unsigned long imbalance; struct rq *busiest; @@ -4138,11 +4492,11 @@ redo: * still unbalanced. ld_moved simply stays zero, so it is * correctly treated as an imbalance. */ - all_pinned = 1; + lb_flags |= LBF_ALL_PINNED; local_irq_save(flags); double_rq_lock(this_rq, busiest); ld_moved = move_tasks(this_rq, this_cpu, busiest, - imbalance, sd, idle, &all_pinned); + imbalance, sd, idle, &lb_flags); double_rq_unlock(this_rq, busiest); local_irq_restore(flags); @@ -4152,8 +4506,18 @@ redo: if (ld_moved && this_cpu != smp_processor_id()) resched_cpu(this_cpu); + if (lb_flags & LBF_ABORT) + goto out_balanced; + + if (lb_flags & LBF_NEED_BREAK) { + lb_flags += LBF_HAD_BREAK - LBF_NEED_BREAK; + if (lb_flags & LBF_ABORT) + goto out_balanced; + goto redo; + } + /* All tasks on this runqueue were pinned by CPU affinity */ - if (unlikely(all_pinned)) { + if (unlikely(lb_flags & LBF_ALL_PINNED)) { cpumask_clear_cpu(cpu_of(busiest), cpus); if (!cpumask_empty(cpus)) goto redo; @@ -4183,7 +4547,7 @@ redo: tsk_cpus_allowed(busiest->curr))) { raw_spin_unlock_irqrestore(&busiest->lock, flags); - all_pinned = 1; + lb_flags |= LBF_ALL_PINNED; goto out_one_pinned; } @@ -4236,7 +4600,8 @@ out_balanced: out_one_pinned: /* tune up the balancing interval */ - if ((all_pinned && sd->balance_interval < MAX_PINNED_INTERVAL) || + if (((lb_flags & LBF_ALL_PINNED) && + sd->balance_interval < MAX_PINNED_INTERVAL) || (sd->balance_interval < sd->max_interval)) sd->balance_interval *= 2; @@ -4249,7 +4614,7 @@ out: * idle_balance is called by schedule() if this_cpu is about to become * idle. Attempts to pull tasks from other CPUs. */ -static void idle_balance(int this_cpu, struct rq *this_rq) +void idle_balance(int this_cpu, struct rq *this_rq) { struct sched_domain *sd; int pulled_task = 0; @@ -4364,28 +4729,16 @@ out_unlock: #ifdef CONFIG_NO_HZ /* * idle load balancing details - * - One of the idle CPUs nominates itself as idle load_balancer, while - * entering idle. - * - This idle load balancer CPU will also go into tickless mode when - * it is idle, just like all other idle CPUs * - When one of the busy CPUs notice that there may be an idle rebalancing * needed, they will kick the idle load balancer, which then does idle * load balancing for all the idle CPUs. */ static struct { - atomic_t load_balancer; - atomic_t first_pick_cpu; - atomic_t second_pick_cpu; cpumask_var_t idle_cpus_mask; - cpumask_var_t grp_idle_mask; + atomic_t nr_cpus; unsigned long next_balance; /* in jiffy units */ } nohz ____cacheline_aligned; -int get_nohz_load_balancer(void) -{ - return atomic_read(&nohz.load_balancer); -} - #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) /** * lowest_flag_domain - Return lowest sched_domain containing flag. @@ -4422,33 +4775,6 @@ static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) (sd && (sd->flags & flag)); sd = sd->parent) /** - * is_semi_idle_group - Checks if the given sched_group is semi-idle. - * @ilb_group: group to be checked for semi-idleness - * - * Returns: 1 if the group is semi-idle. 0 otherwise. - * - * We define a sched_group to be semi idle if it has atleast one idle-CPU - * and atleast one non-idle CPU. This helper function checks if the given - * sched_group is semi-idle or not. - */ -static inline int is_semi_idle_group(struct sched_group *ilb_group) -{ - cpumask_and(nohz.grp_idle_mask, nohz.idle_cpus_mask, - sched_group_cpus(ilb_group)); - - /* - * A sched_group is semi-idle when it has atleast one busy cpu - * and atleast one idle cpu. - */ - if (cpumask_empty(nohz.grp_idle_mask)) - return 0; - - if (cpumask_equal(nohz.grp_idle_mask, sched_group_cpus(ilb_group))) - return 0; - - return 1; -} -/** * find_new_ilb - Finds the optimum idle load balancer for nomination. * @cpu: The cpu which is nominating a new idle_load_balancer. * @@ -4462,9 +4788,9 @@ static inline int is_semi_idle_group(struct sched_group *ilb_group) */ static int find_new_ilb(int cpu) { + int ilb = cpumask_first(nohz.idle_cpus_mask); + struct sched_group *ilbg; struct sched_domain *sd; - struct sched_group *ilb_group; - int ilb = nr_cpu_ids; /* * Have idle load balancer selection from semi-idle packages only @@ -4482,23 +4808,28 @@ static int find_new_ilb(int cpu) rcu_read_lock(); for_each_flag_domain(cpu, sd, SD_POWERSAVINGS_BALANCE) { - ilb_group = sd->groups; + ilbg = sd->groups; do { - if (is_semi_idle_group(ilb_group)) { - ilb = cpumask_first(nohz.grp_idle_mask); + if (ilbg->group_weight != + atomic_read(&ilbg->sgp->nr_busy_cpus)) { + ilb = cpumask_first_and(nohz.idle_cpus_mask, + sched_group_cpus(ilbg)); goto unlock; } - ilb_group = ilb_group->next; + ilbg = ilbg->next; - } while (ilb_group != sd->groups); + } while (ilbg != sd->groups); } unlock: rcu_read_unlock(); out_done: - return ilb; + if (ilb < nr_cpu_ids && idle_cpu(ilb)) + return ilb; + + return nr_cpu_ids; } #else /* (CONFIG_SCHED_MC || CONFIG_SCHED_SMT) */ static inline int find_new_ilb(int call_cpu) @@ -4518,99 +4849,68 @@ static void nohz_balancer_kick(int cpu) nohz.next_balance++; - ilb_cpu = get_nohz_load_balancer(); - - if (ilb_cpu >= nr_cpu_ids) { - ilb_cpu = cpumask_first(nohz.idle_cpus_mask); - if (ilb_cpu >= nr_cpu_ids) - return; - } + ilb_cpu = find_new_ilb(cpu); - if (!cpu_rq(ilb_cpu)->nohz_balance_kick) { - cpu_rq(ilb_cpu)->nohz_balance_kick = 1; + if (ilb_cpu >= nr_cpu_ids) + return; - smp_mb(); - /* - * Use smp_send_reschedule() instead of resched_cpu(). - * This way we generate a sched IPI on the target cpu which - * is idle. And the softirq performing nohz idle load balance - * will be run before returning from the IPI. - */ - smp_send_reschedule(ilb_cpu); - } + if (test_and_set_bit(NOHZ_BALANCE_KICK, nohz_flags(ilb_cpu))) + return; + /* + * Use smp_send_reschedule() instead of resched_cpu(). + * This way we generate a sched IPI on the target cpu which + * is idle. And the softirq performing nohz idle load balance + * will be run before returning from the IPI. + */ + smp_send_reschedule(ilb_cpu); return; } -/* - * This routine will try to nominate the ilb (idle load balancing) - * owner among the cpus whose ticks are stopped. ilb owner will do the idle - * load balancing on behalf of all those cpus. - * - * When the ilb owner becomes busy, we will not have new ilb owner until some - * idle CPU wakes up and goes back to idle or some busy CPU tries to kick - * idle load balancing by kicking one of the idle CPUs. - * - * Ticks are stopped for the ilb owner as well, with busy CPU kicking this - * ilb owner CPU in future (when there is a need for idle load balancing on - * behalf of all idle CPUs). - */ -void select_nohz_load_balancer(int stop_tick) +static inline void set_cpu_sd_state_busy(void) { + struct sched_domain *sd; int cpu = smp_processor_id(); - if (stop_tick) { - if (!cpu_active(cpu)) { - if (atomic_read(&nohz.load_balancer) != cpu) - return; - - /* - * If we are going offline and still the leader, - * give up! - */ - if (atomic_cmpxchg(&nohz.load_balancer, cpu, - nr_cpu_ids) != cpu) - BUG(); + if (!test_bit(NOHZ_IDLE, nohz_flags(cpu))) + return; + clear_bit(NOHZ_IDLE, nohz_flags(cpu)); - return; - } + rcu_read_lock(); + for_each_domain(cpu, sd) + atomic_inc(&sd->groups->sgp->nr_busy_cpus); + rcu_read_unlock(); +} - cpumask_set_cpu(cpu, nohz.idle_cpus_mask); +void set_cpu_sd_state_idle(void) +{ + struct sched_domain *sd; + int cpu = smp_processor_id(); - if (atomic_read(&nohz.first_pick_cpu) == cpu) - atomic_cmpxchg(&nohz.first_pick_cpu, cpu, nr_cpu_ids); - if (atomic_read(&nohz.second_pick_cpu) == cpu) - atomic_cmpxchg(&nohz.second_pick_cpu, cpu, nr_cpu_ids); + if (test_bit(NOHZ_IDLE, nohz_flags(cpu))) + return; + set_bit(NOHZ_IDLE, nohz_flags(cpu)); - if (atomic_read(&nohz.load_balancer) >= nr_cpu_ids) { - int new_ilb; + rcu_read_lock(); + for_each_domain(cpu, sd) + atomic_dec(&sd->groups->sgp->nr_busy_cpus); + rcu_read_unlock(); +} - /* make me the ilb owner */ - if (atomic_cmpxchg(&nohz.load_balancer, nr_cpu_ids, - cpu) != nr_cpu_ids) - return; +/* + * This routine will record that this cpu is going idle with tick stopped. + * This info will be used in performing idle load balancing in the future. + */ +void select_nohz_load_balancer(int stop_tick) +{ + int cpu = smp_processor_id(); - /* - * Check to see if there is a more power-efficient - * ilb. - */ - new_ilb = find_new_ilb(cpu); - if (new_ilb < nr_cpu_ids && new_ilb != cpu) { - atomic_set(&nohz.load_balancer, nr_cpu_ids); - resched_cpu(new_ilb); - return; - } - return; - } - } else { - if (!cpumask_test_cpu(cpu, nohz.idle_cpus_mask)) + if (stop_tick) { + if (test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu))) return; - cpumask_clear_cpu(cpu, nohz.idle_cpus_mask); - - if (atomic_read(&nohz.load_balancer) == cpu) - if (atomic_cmpxchg(&nohz.load_balancer, cpu, - nr_cpu_ids) != cpu) - BUG(); + cpumask_set_cpu(cpu, nohz.idle_cpus_mask); + atomic_inc(&nohz.nr_cpus); + set_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)); } return; } @@ -4624,7 +4924,7 @@ static unsigned long __read_mostly max_load_balance_interval = HZ/10; * Scale the max load_balance interval with the number of CPUs in the system. * This trades load-balance latency on larger machines for less cross talk. */ -static void update_max_interval(void) +void update_max_interval(void) { max_load_balance_interval = HZ*num_online_cpus()/10; } @@ -4716,11 +5016,12 @@ static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle) struct rq *rq; int balance_cpu; - if (idle != CPU_IDLE || !this_rq->nohz_balance_kick) - return; + if (idle != CPU_IDLE || + !test_bit(NOHZ_BALANCE_KICK, nohz_flags(this_cpu))) + goto end; for_each_cpu(balance_cpu, nohz.idle_cpus_mask) { - if (balance_cpu == this_cpu) + if (balance_cpu == this_cpu || !idle_cpu(balance_cpu)) continue; /* @@ -4728,10 +5029,8 @@ static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle) * work being done for other cpus. Next load * balancing owner will pick it up. */ - if (need_resched()) { - this_rq->nohz_balance_kick = 0; + if (need_resched()) break; - } raw_spin_lock_irq(&this_rq->lock); update_rq_clock(this_rq); @@ -4745,53 +5044,75 @@ static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle) this_rq->next_balance = rq->next_balance; } nohz.next_balance = this_rq->next_balance; - this_rq->nohz_balance_kick = 0; +end: + clear_bit(NOHZ_BALANCE_KICK, nohz_flags(this_cpu)); } /* - * Current heuristic for kicking the idle load balancer - * - first_pick_cpu is the one of the busy CPUs. It will kick - * idle load balancer when it has more than one process active. This - * eliminates the need for idle load balancing altogether when we have - * only one running process in the system (common case). - * - If there are more than one busy CPU, idle load balancer may have - * to run for active_load_balance to happen (i.e., two busy CPUs are - * SMT or core siblings and can run better if they move to different - * physical CPUs). So, second_pick_cpu is the second of the busy CPUs - * which will kick idle load balancer as soon as it has any load. + * Current heuristic for kicking the idle load balancer in the presence + * of an idle cpu is the system. + * - This rq has more than one task. + * - At any scheduler domain level, this cpu's scheduler group has multiple + * busy cpu's exceeding the group's power. + * - For SD_ASYM_PACKING, if the lower numbered cpu's in the scheduler + * domain span are idle. */ static inline int nohz_kick_needed(struct rq *rq, int cpu) { unsigned long now = jiffies; - int ret; - int first_pick_cpu, second_pick_cpu; + struct sched_domain *sd; - if (time_before(now, nohz.next_balance)) + if (unlikely(idle_cpu(cpu))) return 0; - if (idle_cpu(cpu)) - return 0; + /* + * We may be recently in ticked or tickless idle mode. At the first + * busy tick after returning from idle, we will update the busy stats. + */ + set_cpu_sd_state_busy(); + if (unlikely(test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))) { + clear_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)); + cpumask_clear_cpu(cpu, nohz.idle_cpus_mask); + atomic_dec(&nohz.nr_cpus); + } - first_pick_cpu = atomic_read(&nohz.first_pick_cpu); - second_pick_cpu = atomic_read(&nohz.second_pick_cpu); + /* + * None are in tickless mode and hence no need for NOHZ idle load + * balancing. + */ + if (likely(!atomic_read(&nohz.nr_cpus))) + return 0; - if (first_pick_cpu < nr_cpu_ids && first_pick_cpu != cpu && - second_pick_cpu < nr_cpu_ids && second_pick_cpu != cpu) + if (time_before(now, nohz.next_balance)) return 0; - ret = atomic_cmpxchg(&nohz.first_pick_cpu, nr_cpu_ids, cpu); - if (ret == nr_cpu_ids || ret == cpu) { - atomic_cmpxchg(&nohz.second_pick_cpu, cpu, nr_cpu_ids); - if (rq->nr_running > 1) - return 1; - } else { - ret = atomic_cmpxchg(&nohz.second_pick_cpu, nr_cpu_ids, cpu); - if (ret == nr_cpu_ids || ret == cpu) { - if (rq->nr_running) - return 1; - } + if (rq->nr_running >= 2) + goto need_kick; + + rcu_read_lock(); + for_each_domain(cpu, sd) { + struct sched_group *sg = sd->groups; + struct sched_group_power *sgp = sg->sgp; + int nr_busy = atomic_read(&sgp->nr_busy_cpus); + + if (sd->flags & SD_SHARE_PKG_RESOURCES && nr_busy > 1) + goto need_kick_unlock; + + if (sd->flags & SD_ASYM_PACKING && nr_busy != sg->group_weight + && (cpumask_first_and(nohz.idle_cpus_mask, + sched_domain_span(sd)) < cpu)) + goto need_kick_unlock; + + if (!(sd->flags & (SD_SHARE_PKG_RESOURCES | SD_ASYM_PACKING))) + break; } + rcu_read_unlock(); return 0; + +need_kick_unlock: + rcu_read_unlock(); +need_kick: + return 1; } #else static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle) { } @@ -4826,14 +5147,14 @@ static inline int on_null_domain(int cpu) /* * Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing. */ -static inline void trigger_load_balance(struct rq *rq, int cpu) +void trigger_load_balance(struct rq *rq, int cpu) { /* Don't need to rebalance while attached to NULL domain */ if (time_after_eq(jiffies, rq->next_balance) && likely(!on_null_domain(cpu))) raise_softirq(SCHED_SOFTIRQ); #ifdef CONFIG_NO_HZ - else if (nohz_kick_needed(rq, cpu) && likely(!on_null_domain(cpu))) + if (nohz_kick_needed(rq, cpu) && likely(!on_null_domain(cpu))) nohz_balancer_kick(cpu); #endif } @@ -4848,15 +5169,6 @@ static void rq_offline_fair(struct rq *rq) update_sysctl(); } -#else /* CONFIG_SMP */ - -/* - * on UP we do not need to balance between CPUs: - */ -static inline void idle_balance(int cpu, struct rq *rq) -{ -} - #endif /* CONFIG_SMP */ /* @@ -4880,8 +5192,8 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued) */ static void task_fork_fair(struct task_struct *p) { - struct cfs_rq *cfs_rq = task_cfs_rq(current); - struct sched_entity *se = &p->se, *curr = cfs_rq->curr; + struct cfs_rq *cfs_rq; + struct sched_entity *se = &p->se, *curr; int this_cpu = smp_processor_id(); struct rq *rq = this_rq(); unsigned long flags; @@ -4890,6 +5202,9 @@ static void task_fork_fair(struct task_struct *p) update_rq_clock(rq); + cfs_rq = task_cfs_rq(current); + curr = cfs_rq->curr; + if (unlikely(task_cpu(p) != this_cpu)) { rcu_read_lock(); __set_task_cpu(p, this_cpu); @@ -4999,6 +5314,16 @@ static void set_curr_task_fair(struct rq *rq) } } +void init_cfs_rq(struct cfs_rq *cfs_rq) +{ + cfs_rq->tasks_timeline = RB_ROOT; + INIT_LIST_HEAD(&cfs_rq->tasks); + cfs_rq->min_vruntime = (u64)(-(1LL << 20)); +#ifndef CONFIG_64BIT + cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime; +#endif +} + #ifdef CONFIG_FAIR_GROUP_SCHED static void task_move_group_fair(struct task_struct *p, int on_rq) { @@ -5015,13 +5340,182 @@ static void task_move_group_fair(struct task_struct *p, int on_rq) * to another cgroup's rq. This does somewhat interfere with the * fair sleeper stuff for the first placement, but who cares. */ + /* + * When !on_rq, vruntime of the task has usually NOT been normalized. + * But there are some cases where it has already been normalized: + * + * - Moving a forked child which is waiting for being woken up by + * wake_up_new_task(). + * - Moving a task which has been woken up by try_to_wake_up() and + * waiting for actually being woken up by sched_ttwu_pending(). + * + * To prevent boost or penalty in the new cfs_rq caused by delta + * min_vruntime between the two cfs_rqs, we skip vruntime adjustment. + */ + if (!on_rq && (!p->se.sum_exec_runtime || p->state == TASK_WAKING)) + on_rq = 1; + if (!on_rq) p->se.vruntime -= cfs_rq_of(&p->se)->min_vruntime; set_task_rq(p, task_cpu(p)); if (!on_rq) p->se.vruntime += cfs_rq_of(&p->se)->min_vruntime; } + +void free_fair_sched_group(struct task_group *tg) +{ + int i; + + destroy_cfs_bandwidth(tg_cfs_bandwidth(tg)); + + for_each_possible_cpu(i) { + if (tg->cfs_rq) + kfree(tg->cfs_rq[i]); + if (tg->se) + kfree(tg->se[i]); + } + + kfree(tg->cfs_rq); + kfree(tg->se); +} + +int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) +{ + struct cfs_rq *cfs_rq; + struct sched_entity *se; + int i; + + tg->cfs_rq = kzalloc(sizeof(cfs_rq) * nr_cpu_ids, GFP_KERNEL); + if (!tg->cfs_rq) + goto err; + tg->se = kzalloc(sizeof(se) * nr_cpu_ids, GFP_KERNEL); + if (!tg->se) + goto err; + + tg->shares = NICE_0_LOAD; + + init_cfs_bandwidth(tg_cfs_bandwidth(tg)); + + for_each_possible_cpu(i) { + cfs_rq = kzalloc_node(sizeof(struct cfs_rq), + GFP_KERNEL, cpu_to_node(i)); + if (!cfs_rq) + goto err; + + se = kzalloc_node(sizeof(struct sched_entity), + GFP_KERNEL, cpu_to_node(i)); + if (!se) + goto err_free_rq; + + init_cfs_rq(cfs_rq); + init_tg_cfs_entry(tg, cfs_rq, se, i, parent->se[i]); + } + + return 1; + +err_free_rq: + kfree(cfs_rq); +err: + return 0; +} + +void unregister_fair_sched_group(struct task_group *tg, int cpu) +{ + struct rq *rq = cpu_rq(cpu); + unsigned long flags; + + /* + * Only empty task groups can be destroyed; so we can speculatively + * check on_list without danger of it being re-added. + */ + if (!tg->cfs_rq[cpu]->on_list) + return; + + raw_spin_lock_irqsave(&rq->lock, flags); + list_del_leaf_cfs_rq(tg->cfs_rq[cpu]); + raw_spin_unlock_irqrestore(&rq->lock, flags); +} + +void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, + struct sched_entity *se, int cpu, + struct sched_entity *parent) +{ + struct rq *rq = cpu_rq(cpu); + + cfs_rq->tg = tg; + cfs_rq->rq = rq; +#ifdef CONFIG_SMP + /* allow initial update_cfs_load() to truncate */ + cfs_rq->load_stamp = 1; #endif + init_cfs_rq_runtime(cfs_rq); + + tg->cfs_rq[cpu] = cfs_rq; + tg->se[cpu] = se; + + /* se could be NULL for root_task_group */ + if (!se) + return; + + if (!parent) + se->cfs_rq = &rq->cfs; + else + se->cfs_rq = parent->my_q; + + se->my_q = cfs_rq; + update_load_set(&se->load, 0); + se->parent = parent; +} + +static DEFINE_MUTEX(shares_mutex); + +int sched_group_set_shares(struct task_group *tg, unsigned long shares) +{ + int i; + unsigned long flags; + + /* + * We can't change the weight of the root cgroup. + */ + if (!tg->se[0]) + return -EINVAL; + + shares = clamp(shares, scale_load(MIN_SHARES), scale_load(MAX_SHARES)); + + mutex_lock(&shares_mutex); + if (tg->shares == shares) + goto done; + + tg->shares = shares; + for_each_possible_cpu(i) { + struct rq *rq = cpu_rq(i); + struct sched_entity *se; + + se = tg->se[i]; + /* Propagate contribution to hierarchy */ + raw_spin_lock_irqsave(&rq->lock, flags); + for_each_sched_entity(se) + update_cfs_shares(group_cfs_rq(se)); + raw_spin_unlock_irqrestore(&rq->lock, flags); + } + +done: + mutex_unlock(&shares_mutex); + return 0; +} +#else /* CONFIG_FAIR_GROUP_SCHED */ + +void free_fair_sched_group(struct task_group *tg) { } + +int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) +{ + return 1; +} + +void unregister_fair_sched_group(struct task_group *tg, int cpu) { } + +#endif /* CONFIG_FAIR_GROUP_SCHED */ + static unsigned int get_rr_interval_fair(struct rq *rq, struct task_struct *task) { @@ -5041,7 +5535,7 @@ static unsigned int get_rr_interval_fair(struct rq *rq, struct task_struct *task /* * All the scheduling class methods: */ -static const struct sched_class fair_sched_class = { +const struct sched_class fair_sched_class = { .next = &idle_sched_class, .enqueue_task = enqueue_task_fair, .dequeue_task = dequeue_task_fair, @@ -5078,7 +5572,7 @@ static const struct sched_class fair_sched_class = { }; #ifdef CONFIG_SCHED_DEBUG -static void print_cfs_stats(struct seq_file *m, int cpu) +void print_cfs_stats(struct seq_file *m, int cpu) { struct cfs_rq *cfs_rq; @@ -5088,3 +5582,15 @@ static void print_cfs_stats(struct seq_file *m, int cpu) rcu_read_unlock(); } #endif + +__init void init_sched_fair_class(void) +{ +#ifdef CONFIG_SMP + open_softirq(SCHED_SOFTIRQ, run_rebalance_domains); + +#ifdef CONFIG_NO_HZ + zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT); +#endif +#endif /* SMP */ + +} diff --git a/kernel/sched_features.h b/kernel/sched/features.h index 8480224..e61fd73 100644 --- a/kernel/sched_features.h +++ b/kernel/sched/features.h @@ -3,13 +3,13 @@ * them to run sooner, but does not allow tons of sleepers to * rip the spread apart. */ -SCHED_FEAT(GENTLE_FAIR_SLEEPERS, 1) +SCHED_FEAT(GENTLE_FAIR_SLEEPERS, true) /* * Place new tasks ahead so that they do not starve already running * tasks */ -SCHED_FEAT(START_DEBIT, 1) +SCHED_FEAT(START_DEBIT, true) /* * Based on load and program behaviour, see if it makes sense to place @@ -17,54 +17,54 @@ SCHED_FEAT(START_DEBIT, 1) * improve cache locality. Typically used with SYNC wakeups as * generated by pipes and the like, see also SYNC_WAKEUPS. */ -SCHED_FEAT(AFFINE_WAKEUPS, 1) +SCHED_FEAT(AFFINE_WAKEUPS, true) /* * 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) +SCHED_FEAT(NEXT_BUDDY, false) /* * 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) +SCHED_FEAT(LAST_BUDDY, true) /* * 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(CACHE_HOT_BUDDY, true) /* * Use arch dependent cpu power functions */ -SCHED_FEAT(ARCH_POWER, 0) +SCHED_FEAT(ARCH_POWER, false) -SCHED_FEAT(HRTICK, 0) -SCHED_FEAT(DOUBLE_TICK, 0) -SCHED_FEAT(LB_BIAS, 1) +SCHED_FEAT(HRTICK, false) +SCHED_FEAT(DOUBLE_TICK, false) +SCHED_FEAT(LB_BIAS, true) /* * 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) +SCHED_FEAT(OWNER_SPIN, true) /* * Decrement CPU power based on time not spent running tasks */ -SCHED_FEAT(NONTASK_POWER, 1) +SCHED_FEAT(NONTASK_POWER, true) /* * Queue remote wakeups on the target CPU and process them * using the scheduler IPI. Reduces rq->lock contention/bounces. */ -SCHED_FEAT(TTWU_QUEUE, 1) +SCHED_FEAT(TTWU_QUEUE, true) -SCHED_FEAT(FORCE_SD_OVERLAP, 0) -SCHED_FEAT(RT_RUNTIME_SHARE, 1) +SCHED_FEAT(FORCE_SD_OVERLAP, false) +SCHED_FEAT(RT_RUNTIME_SHARE, true) diff --git a/kernel/sched_idletask.c b/kernel/sched/idle_task.c index 0a51882..91b4c95 100644 --- a/kernel/sched_idletask.c +++ b/kernel/sched/idle_task.c @@ -1,3 +1,5 @@ +#include "sched.h" + /* * idle-task scheduling class. * @@ -71,7 +73,7 @@ static unsigned int get_rr_interval_idle(struct rq *rq, struct task_struct *task /* * Simple, special scheduling class for the per-CPU idle tasks: */ -static const struct sched_class idle_sched_class = { +const struct sched_class idle_sched_class = { /* .next is NULL */ /* no enqueue/yield_task for idle tasks */ diff --git a/kernel/sched_rt.c b/kernel/sched/rt.c index 583a136..3640ebb 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched/rt.c @@ -3,7 +3,92 @@ * policies) */ +#include "sched.h" + +#include <linux/slab.h> + +static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun); + +struct rt_bandwidth def_rt_bandwidth; + +static enum hrtimer_restart sched_rt_period_timer(struct hrtimer *timer) +{ + struct rt_bandwidth *rt_b = + container_of(timer, struct rt_bandwidth, rt_period_timer); + ktime_t now; + int overrun; + int idle = 0; + + for (;;) { + now = hrtimer_cb_get_time(timer); + overrun = hrtimer_forward(timer, now, rt_b->rt_period); + + if (!overrun) + break; + + idle = do_sched_rt_period_timer(rt_b, overrun); + } + + return idle ? HRTIMER_NORESTART : HRTIMER_RESTART; +} + +void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime) +{ + rt_b->rt_period = ns_to_ktime(period); + rt_b->rt_runtime = runtime; + + raw_spin_lock_init(&rt_b->rt_runtime_lock); + + hrtimer_init(&rt_b->rt_period_timer, + CLOCK_MONOTONIC, HRTIMER_MODE_REL); + rt_b->rt_period_timer.function = sched_rt_period_timer; +} + +static void start_rt_bandwidth(struct rt_bandwidth *rt_b) +{ + if (!rt_bandwidth_enabled() || rt_b->rt_runtime == RUNTIME_INF) + return; + + if (hrtimer_active(&rt_b->rt_period_timer)) + return; + + raw_spin_lock(&rt_b->rt_runtime_lock); + start_bandwidth_timer(&rt_b->rt_period_timer, rt_b->rt_period); + raw_spin_unlock(&rt_b->rt_runtime_lock); +} + +void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq) +{ + struct rt_prio_array *array; + int i; + + array = &rt_rq->active; + for (i = 0; i < MAX_RT_PRIO; i++) { + INIT_LIST_HEAD(array->queue + i); + __clear_bit(i, array->bitmap); + } + /* delimiter for bitsearch: */ + __set_bit(MAX_RT_PRIO, array->bitmap); + +#if defined CONFIG_SMP + rt_rq->highest_prio.curr = MAX_RT_PRIO; + rt_rq->highest_prio.next = MAX_RT_PRIO; + rt_rq->rt_nr_migratory = 0; + rt_rq->overloaded = 0; + plist_head_init(&rt_rq->pushable_tasks); +#endif + + rt_rq->rt_time = 0; + rt_rq->rt_throttled = 0; + rt_rq->rt_runtime = 0; + raw_spin_lock_init(&rt_rq->rt_runtime_lock); +} + #ifdef CONFIG_RT_GROUP_SCHED +static void destroy_rt_bandwidth(struct rt_bandwidth *rt_b) +{ + hrtimer_cancel(&rt_b->rt_period_timer); +} #define rt_entity_is_task(rt_se) (!(rt_se)->my_q) @@ -25,6 +110,91 @@ static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se) return rt_se->rt_rq; } +void free_rt_sched_group(struct task_group *tg) +{ + int i; + + if (tg->rt_se) + destroy_rt_bandwidth(&tg->rt_bandwidth); + + for_each_possible_cpu(i) { + if (tg->rt_rq) + kfree(tg->rt_rq[i]); + if (tg->rt_se) + kfree(tg->rt_se[i]); + } + + kfree(tg->rt_rq); + kfree(tg->rt_se); +} + +void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, + struct sched_rt_entity *rt_se, int cpu, + struct sched_rt_entity *parent) +{ + struct rq *rq = cpu_rq(cpu); + + rt_rq->highest_prio.curr = MAX_RT_PRIO; + rt_rq->rt_nr_boosted = 0; + rt_rq->rq = rq; + rt_rq->tg = tg; + + tg->rt_rq[cpu] = rt_rq; + tg->rt_se[cpu] = rt_se; + + if (!rt_se) + return; + + if (!parent) + rt_se->rt_rq = &rq->rt; + else + rt_se->rt_rq = parent->my_q; + + rt_se->my_q = rt_rq; + rt_se->parent = parent; + INIT_LIST_HEAD(&rt_se->run_list); +} + +int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent) +{ + struct rt_rq *rt_rq; + struct sched_rt_entity *rt_se; + int i; + + tg->rt_rq = kzalloc(sizeof(rt_rq) * nr_cpu_ids, GFP_KERNEL); + if (!tg->rt_rq) + goto err; + tg->rt_se = kzalloc(sizeof(rt_se) * nr_cpu_ids, GFP_KERNEL); + if (!tg->rt_se) + goto err; + + init_rt_bandwidth(&tg->rt_bandwidth, + ktime_to_ns(def_rt_bandwidth.rt_period), 0); + + for_each_possible_cpu(i) { + rt_rq = kzalloc_node(sizeof(struct rt_rq), + GFP_KERNEL, cpu_to_node(i)); + if (!rt_rq) + goto err; + + rt_se = kzalloc_node(sizeof(struct sched_rt_entity), + GFP_KERNEL, cpu_to_node(i)); + if (!rt_se) + goto err_free_rq; + + init_rt_rq(rt_rq, cpu_rq(i)); + rt_rq->rt_runtime = tg->rt_bandwidth.rt_runtime; + init_tg_rt_entry(tg, rt_rq, rt_se, i, parent->rt_se[i]); + } + + return 1; + +err_free_rq: + kfree(rt_rq); +err: + return 0; +} + #else /* CONFIG_RT_GROUP_SCHED */ #define rt_entity_is_task(rt_se) (1) @@ -47,6 +217,12 @@ static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se) return &rq->rt; } +void free_rt_sched_group(struct task_group *tg) { } + +int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent) +{ + return 1; +} #endif /* CONFIG_RT_GROUP_SCHED */ #ifdef CONFIG_SMP @@ -556,6 +732,28 @@ static void enable_runtime(struct rq *rq) raw_spin_unlock_irqrestore(&rq->lock, flags); } +int update_runtime(struct notifier_block *nfb, unsigned long action, void *hcpu) +{ + int cpu = (int)(long)hcpu; + + switch (action) { + case CPU_DOWN_PREPARE: + case CPU_DOWN_PREPARE_FROZEN: + disable_runtime(cpu_rq(cpu)); + return NOTIFY_OK; + + case CPU_DOWN_FAILED: + case CPU_DOWN_FAILED_FROZEN: + case CPU_ONLINE: + case CPU_ONLINE_FROZEN: + enable_runtime(cpu_rq(cpu)); + return NOTIFY_OK; + + default: + return NOTIFY_DONE; + } +} + static int balance_runtime(struct rt_rq *rt_rq) { int more = 0; @@ -648,7 +846,7 @@ static int sched_rt_runtime_exceeded(struct rt_rq *rt_rq) if (rt_rq->rt_throttled) return rt_rq_throttled(rt_rq); - if (sched_rt_runtime(rt_rq) >= sched_rt_period(rt_rq)) + if (runtime >= sched_rt_period(rt_rq)) return 0; balance_runtime(rt_rq); @@ -957,8 +1155,8 @@ static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int flags) } /* - * Put task to the end of the run list without the overhead of dequeue - * followed by enqueue. + * Put task to the head or the end of the run list without the overhead of + * dequeue followed by enqueue. */ static void requeue_rt_entity(struct rt_rq *rt_rq, struct sched_rt_entity *rt_se, int head) @@ -1002,6 +1200,9 @@ select_task_rq_rt(struct task_struct *p, int sd_flag, int flags) cpu = task_cpu(p); + if (p->rt.nr_cpus_allowed == 1) + goto out; + /* For anything but wake ups, just return the task_cpu */ if (sd_flag != SD_BALANCE_WAKE && sd_flag != SD_BALANCE_FORK) goto out; @@ -1178,8 +1379,6 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p) /* Only try algorithms three times */ #define RT_MAX_TRIES 3 -static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep); - static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu) { if (!task_running(rq, p) && @@ -1653,13 +1852,14 @@ static void switched_from_rt(struct rq *rq, struct task_struct *p) pull_rt_task(rq); } -static inline void init_sched_rt_class(void) +void init_sched_rt_class(void) { unsigned int i; - for_each_possible_cpu(i) + for_each_possible_cpu(i) { zalloc_cpumask_var_node(&per_cpu(local_cpu_mask, i), GFP_KERNEL, cpu_to_node(i)); + } } #endif /* CONFIG_SMP */ @@ -1800,7 +2000,7 @@ static unsigned int get_rr_interval_rt(struct rq *rq, struct task_struct *task) return 0; } -static const struct sched_class rt_sched_class = { +const struct sched_class rt_sched_class = { .next = &fair_sched_class, .enqueue_task = enqueue_task_rt, .dequeue_task = dequeue_task_rt, @@ -1835,7 +2035,7 @@ static const struct sched_class rt_sched_class = { #ifdef CONFIG_SCHED_DEBUG extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); -static void print_rt_stats(struct seq_file *m, int cpu) +void print_rt_stats(struct seq_file *m, int cpu) { rt_rq_iter_t iter; struct rt_rq *rt_rq; diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h new file mode 100644 index 0000000..98c0c26 --- /dev/null +++ b/kernel/sched/sched.h @@ -0,0 +1,1166 @@ + +#include <linux/sched.h> +#include <linux/mutex.h> +#include <linux/spinlock.h> +#include <linux/stop_machine.h> + +#include "cpupri.h" + +extern __read_mostly int scheduler_running; + +/* + * Convert user-nice values [ -20 ... 0 ... 19 ] + * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ], + * and back. + */ +#define NICE_TO_PRIO(nice) (MAX_RT_PRIO + (nice) + 20) +#define PRIO_TO_NICE(prio) ((prio) - MAX_RT_PRIO - 20) +#define TASK_NICE(p) PRIO_TO_NICE((p)->static_prio) + +/* + * 'User priority' is the nice value converted to something we + * can work with better when scaling various scheduler parameters, + * it's a [ 0 ... 39 ] range. + */ +#define USER_PRIO(p) ((p)-MAX_RT_PRIO) +#define TASK_USER_PRIO(p) USER_PRIO((p)->static_prio) +#define MAX_USER_PRIO (USER_PRIO(MAX_PRIO)) + +/* + * Helpers for converting nanosecond timing to jiffy resolution + */ +#define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ)) + +#define NICE_0_LOAD SCHED_LOAD_SCALE +#define NICE_0_SHIFT SCHED_LOAD_SHIFT + +/* + * These are the 'tuning knobs' of the scheduler: + * + * default timeslice is 100 msecs (used only for SCHED_RR tasks). + * Timeslices get refilled after they expire. + */ +#define DEF_TIMESLICE (100 * HZ / 1000) + +/* + * single value that denotes runtime == period, ie unlimited time. + */ +#define RUNTIME_INF ((u64)~0ULL) + +static inline int rt_policy(int policy) +{ + if (policy == SCHED_FIFO || policy == SCHED_RR) + return 1; + return 0; +} + +static inline int task_has_rt_policy(struct task_struct *p) +{ + return rt_policy(p->policy); +} + +/* + * This is the priority-queue data structure of the RT scheduling class: + */ +struct rt_prio_array { + DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */ + struct list_head queue[MAX_RT_PRIO]; +}; + +struct rt_bandwidth { + /* nests inside the rq lock: */ + raw_spinlock_t rt_runtime_lock; + ktime_t rt_period; + u64 rt_runtime; + struct hrtimer rt_period_timer; +}; + +extern struct mutex sched_domains_mutex; + +#ifdef CONFIG_CGROUP_SCHED + +#include <linux/cgroup.h> + +struct cfs_rq; +struct rt_rq; + +static LIST_HEAD(task_groups); + +struct cfs_bandwidth { +#ifdef CONFIG_CFS_BANDWIDTH + raw_spinlock_t lock; + ktime_t period; + u64 quota, runtime; + s64 hierarchal_quota; + u64 runtime_expires; + + int idle, timer_active; + struct hrtimer period_timer, slack_timer; + struct list_head throttled_cfs_rq; + + /* statistics */ + int nr_periods, nr_throttled; + u64 throttled_time; +#endif +}; + +/* task group related information */ +struct task_group { + struct cgroup_subsys_state css; + +#ifdef CONFIG_FAIR_GROUP_SCHED + /* schedulable entities of this group on each cpu */ + struct sched_entity **se; + /* runqueue "owned" by this group on each cpu */ + struct cfs_rq **cfs_rq; + unsigned long shares; + + atomic_t load_weight; +#endif + +#ifdef CONFIG_RT_GROUP_SCHED + struct sched_rt_entity **rt_se; + struct rt_rq **rt_rq; + + struct rt_bandwidth rt_bandwidth; +#endif + + struct rcu_head rcu; + struct list_head list; + + struct task_group *parent; + struct list_head siblings; + struct list_head children; + +#ifdef CONFIG_SCHED_AUTOGROUP + struct autogroup *autogroup; +#endif + + struct cfs_bandwidth cfs_bandwidth; +}; + +#ifdef CONFIG_FAIR_GROUP_SCHED +#define ROOT_TASK_GROUP_LOAD NICE_0_LOAD + +/* + * A weight of 0 or 1 can cause arithmetics problems. + * A weight of a cfs_rq is the sum of weights of which entities + * are queued on this cfs_rq, so a weight of a entity should not be + * too large, so as the shares value of a task group. + * (The default weight is 1024 - so there's no practical + * limitation from this.) + */ +#define MIN_SHARES (1UL << 1) +#define MAX_SHARES (1UL << 18) +#endif + +/* Default task group. + * Every task in system belong to this group at bootup. + */ +extern struct task_group root_task_group; + +typedef int (*tg_visitor)(struct task_group *, void *); + +extern int walk_tg_tree_from(struct task_group *from, + tg_visitor down, tg_visitor up, void *data); + +/* + * Iterate the full tree, calling @down when first entering a node and @up when + * leaving it for the final time. + * + * Caller must hold rcu_lock or sufficient equivalent. + */ +static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data) +{ + return walk_tg_tree_from(&root_task_group, down, up, data); +} + +extern int tg_nop(struct task_group *tg, void *data); + +extern void free_fair_sched_group(struct task_group *tg); +extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent); +extern void unregister_fair_sched_group(struct task_group *tg, int cpu); +extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, + struct sched_entity *se, int cpu, + struct sched_entity *parent); +extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b); +extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); + +extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b); +extern void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b); +extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq); + +extern void free_rt_sched_group(struct task_group *tg); +extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent); +extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, + struct sched_rt_entity *rt_se, int cpu, + struct sched_rt_entity *parent); + +#else /* CONFIG_CGROUP_SCHED */ + +struct cfs_bandwidth { }; + +#endif /* CONFIG_CGROUP_SCHED */ + +/* CFS-related fields in a runqueue */ +struct cfs_rq { + struct load_weight load; + unsigned long nr_running, h_nr_running; + + u64 exec_clock; + u64 min_vruntime; +#ifndef CONFIG_64BIT + u64 min_vruntime_copy; +#endif + + struct rb_root tasks_timeline; + struct rb_node *rb_leftmost; + + struct list_head tasks; + struct list_head *balance_iterator; + + /* + * 'curr' points to currently running entity on this cfs_rq. + * It is set to NULL otherwise (i.e when none are currently running). + */ + struct sched_entity *curr, *next, *last, *skip; + +#ifdef CONFIG_SCHED_DEBUG + unsigned int nr_spread_over; +#endif + +#ifdef CONFIG_FAIR_GROUP_SCHED + struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */ + + /* + * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in + * a hierarchy). Non-leaf lrqs hold other higher schedulable entities + * (like users, containers etc.) + * + * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This + * list is used during load balance. + */ + int on_list; + struct list_head leaf_cfs_rq_list; + struct task_group *tg; /* group that "owns" this runqueue */ + +#ifdef CONFIG_SMP + /* + * the part of load.weight contributed by tasks + */ + unsigned long task_weight; + + /* + * h_load = weight * f(tg) + * + * Where f(tg) is the recursive weight fraction assigned to + * this group. + */ + unsigned long h_load; + + /* + * Maintaining per-cpu shares distribution for group scheduling + * + * load_stamp is the last time we updated the load average + * load_last is the last time we updated the load average and saw load + * load_unacc_exec_time is currently unaccounted execution time + */ + u64 load_avg; + u64 load_period; + u64 load_stamp, load_last, load_unacc_exec_time; + + unsigned long load_contribution; +#endif /* CONFIG_SMP */ +#ifdef CONFIG_CFS_BANDWIDTH + int runtime_enabled; + u64 runtime_expires; + s64 runtime_remaining; + + u64 throttled_timestamp; + int throttled, throttle_count; + struct list_head throttled_list; +#endif /* CONFIG_CFS_BANDWIDTH */ +#endif /* CONFIG_FAIR_GROUP_SCHED */ +}; + +static inline int rt_bandwidth_enabled(void) +{ + return sysctl_sched_rt_runtime >= 0; +} + +/* Real-Time classes' related field in a runqueue: */ +struct rt_rq { + struct rt_prio_array active; + unsigned long rt_nr_running; +#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED + struct { + int curr; /* highest queued rt task prio */ +#ifdef CONFIG_SMP + int next; /* next highest */ +#endif + } highest_prio; +#endif +#ifdef CONFIG_SMP + unsigned long rt_nr_migratory; + unsigned long rt_nr_total; + int overloaded; + struct plist_head pushable_tasks; +#endif + int rt_throttled; + u64 rt_time; + u64 rt_runtime; + /* Nests inside the rq lock: */ + raw_spinlock_t rt_runtime_lock; + +#ifdef CONFIG_RT_GROUP_SCHED + unsigned long rt_nr_boosted; + + struct rq *rq; + struct list_head leaf_rt_rq_list; + struct task_group *tg; +#endif +}; + +#ifdef CONFIG_SMP + +/* + * We add the notion of a root-domain which will be used to define per-domain + * variables. Each exclusive cpuset essentially defines an island domain by + * fully partitioning the member cpus from any other cpuset. Whenever a new + * exclusive cpuset is created, we also create and attach a new root-domain + * object. + * + */ +struct root_domain { + atomic_t refcount; + atomic_t rto_count; + struct rcu_head rcu; + cpumask_var_t span; + cpumask_var_t online; + + /* + * The "RT overload" flag: it gets set if a CPU has more than + * one runnable RT task. + */ + cpumask_var_t rto_mask; + struct cpupri cpupri; +}; + +extern struct root_domain def_root_domain; + +#endif /* CONFIG_SMP */ + +/* + * This is the main, per-CPU runqueue data structure. + * + * Locking rule: those places that want to lock multiple runqueues + * (such as the load balancing or the thread migration code), lock + * acquire operations must be ordered by ascending &runqueue. + */ +struct rq { + /* runqueue lock: */ + raw_spinlock_t lock; + + /* + * nr_running and cpu_load should be in the same cacheline because + * remote CPUs use both these fields when doing load calculation. + */ + unsigned long nr_running; + #define CPU_LOAD_IDX_MAX 5 + unsigned long cpu_load[CPU_LOAD_IDX_MAX]; + unsigned long last_load_update_tick; +#ifdef CONFIG_NO_HZ + u64 nohz_stamp; + unsigned long nohz_flags; +#endif + int skip_clock_update; + + /* capture load from *all* tasks on this cpu: */ + struct load_weight load; + unsigned long nr_load_updates; + u64 nr_switches; + + struct cfs_rq cfs; + struct rt_rq rt; + +#ifdef CONFIG_FAIR_GROUP_SCHED + /* list of leaf cfs_rq on this cpu: */ + struct list_head leaf_cfs_rq_list; +#endif +#ifdef CONFIG_RT_GROUP_SCHED + struct list_head leaf_rt_rq_list; +#endif + + /* + * This is part of a global counter where only the total sum + * over all CPUs matters. A task can increase this counter on + * one CPU and if it got migrated afterwards it may decrease + * it on another CPU. Always updated under the runqueue lock: + */ + unsigned long nr_uninterruptible; + + struct task_struct *curr, *idle, *stop; + unsigned long next_balance; + struct mm_struct *prev_mm; + + u64 clock; + u64 clock_task; + + atomic_t nr_iowait; + +#ifdef CONFIG_SMP + struct root_domain *rd; + struct sched_domain *sd; + + unsigned long cpu_power; + + unsigned char idle_balance; + /* For active balancing */ + int post_schedule; + int active_balance; + int push_cpu; + struct cpu_stop_work active_balance_work; + /* cpu of this runqueue: */ + int cpu; + int online; + + u64 rt_avg; + u64 age_stamp; + u64 idle_stamp; + u64 avg_idle; +#endif + +#ifdef CONFIG_IRQ_TIME_ACCOUNTING + u64 prev_irq_time; +#endif +#ifdef CONFIG_PARAVIRT + u64 prev_steal_time; +#endif +#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING + u64 prev_steal_time_rq; +#endif + + /* calc_load related fields */ + unsigned long calc_load_update; + long calc_load_active; + +#ifdef CONFIG_SCHED_HRTICK +#ifdef CONFIG_SMP + int hrtick_csd_pending; + struct call_single_data hrtick_csd; +#endif + struct hrtimer hrtick_timer; +#endif + +#ifdef CONFIG_SCHEDSTATS + /* latency stats */ + struct sched_info rq_sched_info; + unsigned long long rq_cpu_time; + /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */ + + /* sys_sched_yield() stats */ + unsigned int yld_count; + + /* schedule() stats */ + unsigned int sched_switch; + unsigned int sched_count; + unsigned int sched_goidle; + + /* try_to_wake_up() stats */ + unsigned int ttwu_count; + unsigned int ttwu_local; +#endif + +#ifdef CONFIG_SMP + struct llist_head wake_list; +#endif +}; + +static inline int cpu_of(struct rq *rq) +{ +#ifdef CONFIG_SMP + return rq->cpu; +#else + return 0; +#endif +} + +DECLARE_PER_CPU(struct rq, runqueues); + +#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) +#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)) + +#ifdef CONFIG_SMP + +#define rcu_dereference_check_sched_domain(p) \ + rcu_dereference_check((p), \ + lockdep_is_held(&sched_domains_mutex)) + +/* + * The domain tree (rq->sd) is protected by RCU's quiescent state transition. + * See detach_destroy_domains: synchronize_sched for details. + * + * The domain tree of any CPU may only be accessed from within + * preempt-disabled sections. + */ +#define for_each_domain(cpu, __sd) \ + for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \ + __sd; __sd = __sd->parent) + +#define for_each_lower_domain(sd) for (; sd; sd = sd->child) + +/** + * highest_flag_domain - Return highest sched_domain containing flag. + * @cpu: The cpu whose highest level of sched domain is to + * be returned. + * @flag: The flag to check for the highest sched_domain + * for the given cpu. + * + * Returns the highest sched_domain of a cpu which contains the given flag. + */ +static inline struct sched_domain *highest_flag_domain(int cpu, int flag) +{ + struct sched_domain *sd, *hsd = NULL; + + for_each_domain(cpu, sd) { + if (!(sd->flags & flag)) + break; + hsd = sd; + } + + return hsd; +} + +DECLARE_PER_CPU(struct sched_domain *, sd_llc); +DECLARE_PER_CPU(int, sd_llc_id); + +#endif /* CONFIG_SMP */ + +#include "stats.h" +#include "auto_group.h" + +#ifdef CONFIG_CGROUP_SCHED + +/* + * Return the group to which this tasks belongs. + * + * We use task_subsys_state_check() and extend the RCU verification with + * pi->lock and rq->lock because cpu_cgroup_attach() holds those locks for each + * task it moves into the cgroup. Therefore by holding either of those locks, + * we pin the task to the current cgroup. + */ +static inline struct task_group *task_group(struct task_struct *p) +{ + struct task_group *tg; + struct cgroup_subsys_state *css; + + css = task_subsys_state_check(p, cpu_cgroup_subsys_id, + lockdep_is_held(&p->pi_lock) || + lockdep_is_held(&task_rq(p)->lock)); + tg = container_of(css, struct task_group, css); + + return autogroup_task_group(p, tg); +} + +/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ +static inline void set_task_rq(struct task_struct *p, unsigned int cpu) +{ +#if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) + struct task_group *tg = task_group(p); +#endif + +#ifdef CONFIG_FAIR_GROUP_SCHED + p->se.cfs_rq = tg->cfs_rq[cpu]; + p->se.parent = tg->se[cpu]; +#endif + +#ifdef CONFIG_RT_GROUP_SCHED + p->rt.rt_rq = tg->rt_rq[cpu]; + p->rt.parent = tg->rt_se[cpu]; +#endif +} + +#else /* CONFIG_CGROUP_SCHED */ + +static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } +static inline struct task_group *task_group(struct task_struct *p) +{ + return NULL; +} + +#endif /* CONFIG_CGROUP_SCHED */ + +static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) +{ + set_task_rq(p, cpu); +#ifdef CONFIG_SMP + /* + * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be + * successfuly executed on another CPU. We must ensure that updates of + * per-task data have been completed by this moment. + */ + smp_wmb(); + task_thread_info(p)->cpu = cpu; +#endif +} + +/* + * Tunables that become constants when CONFIG_SCHED_DEBUG is off: + */ +#ifdef CONFIG_SCHED_DEBUG +# include <linux/jump_label.h> +# define const_debug __read_mostly +#else +# define const_debug const +#endif + +extern const_debug unsigned int sysctl_sched_features; + +#define SCHED_FEAT(name, enabled) \ + __SCHED_FEAT_##name , + +enum { +#include "features.h" + __SCHED_FEAT_NR, +}; + +#undef SCHED_FEAT + +#if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL) +static __always_inline bool static_branch__true(struct jump_label_key *key) +{ + return likely(static_branch(key)); /* Not out of line branch. */ +} + +static __always_inline bool static_branch__false(struct jump_label_key *key) +{ + return unlikely(static_branch(key)); /* Out of line branch. */ +} + +#define SCHED_FEAT(name, enabled) \ +static __always_inline bool static_branch_##name(struct jump_label_key *key) \ +{ \ + return static_branch__##enabled(key); \ +} + +#include "features.h" + +#undef SCHED_FEAT + +extern struct jump_label_key sched_feat_keys[__SCHED_FEAT_NR]; +#define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x])) +#else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */ +#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) +#endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */ + +static inline u64 global_rt_period(void) +{ + return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; +} + +static inline u64 global_rt_runtime(void) +{ + if (sysctl_sched_rt_runtime < 0) + return RUNTIME_INF; + + return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; +} + + + +static inline int task_current(struct rq *rq, struct task_struct *p) +{ + return rq->curr == p; +} + +static inline int task_running(struct rq *rq, struct task_struct *p) +{ +#ifdef CONFIG_SMP + return p->on_cpu; +#else + return task_current(rq, p); +#endif +} + + +#ifndef prepare_arch_switch +# define prepare_arch_switch(next) do { } while (0) +#endif +#ifndef finish_arch_switch +# define finish_arch_switch(prev) do { } while (0) +#endif + +#ifndef __ARCH_WANT_UNLOCKED_CTXSW +static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) +{ +#ifdef CONFIG_SMP + /* + * We can optimise this out completely for !SMP, because the + * SMP rebalancing from interrupt is the only thing that cares + * here. + */ + next->on_cpu = 1; +#endif +} + +static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) +{ +#ifdef CONFIG_SMP + /* + * After ->on_cpu is cleared, the task can be moved to a different CPU. + * We must ensure this doesn't happen until the switch is completely + * finished. + */ + smp_wmb(); + prev->on_cpu = 0; +#endif +#ifdef CONFIG_DEBUG_SPINLOCK + /* this is a valid case when another task releases the spinlock */ + rq->lock.owner = current; +#endif + /* + * If we are tracking spinlock dependencies then we have to + * fix up the runqueue lock - which gets 'carried over' from + * prev into current: + */ + spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_); + + raw_spin_unlock_irq(&rq->lock); +} + +#else /* __ARCH_WANT_UNLOCKED_CTXSW */ +static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) +{ +#ifdef CONFIG_SMP + /* + * We can optimise this out completely for !SMP, because the + * SMP rebalancing from interrupt is the only thing that cares + * here. + */ + next->on_cpu = 1; +#endif +#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW + raw_spin_unlock_irq(&rq->lock); +#else + raw_spin_unlock(&rq->lock); +#endif +} + +static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) +{ +#ifdef CONFIG_SMP + /* + * After ->on_cpu is cleared, the task can be moved to a different CPU. + * We must ensure this doesn't happen until the switch is completely + * finished. + */ + smp_wmb(); + prev->on_cpu = 0; +#endif +#ifndef __ARCH_WANT_INTERRUPTS_ON_CTXSW + local_irq_enable(); +#endif +} +#endif /* __ARCH_WANT_UNLOCKED_CTXSW */ + + +static inline void update_load_add(struct load_weight *lw, unsigned long inc) +{ + lw->weight += inc; + lw->inv_weight = 0; +} + +static inline void update_load_sub(struct load_weight *lw, unsigned long dec) +{ + lw->weight -= dec; + lw->inv_weight = 0; +} + +static inline void update_load_set(struct load_weight *lw, unsigned long w) +{ + lw->weight = w; + lw->inv_weight = 0; +} + +/* + * To aid in avoiding the subversion of "niceness" due to uneven distribution + * of tasks with abnormal "nice" values across CPUs the contribution that + * each task makes to its run queue's load is weighted according to its + * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a + * scaled version of the new time slice allocation that they receive on time + * slice expiry etc. + */ + +#define WEIGHT_IDLEPRIO 3 +#define WMULT_IDLEPRIO 1431655765 + +/* + * Nice levels are multiplicative, with a gentle 10% change for every + * nice level changed. I.e. when a CPU-bound task goes from nice 0 to + * nice 1, it will get ~10% less CPU time than another CPU-bound task + * that remained on nice 0. + * + * The "10% effect" is relative and cumulative: from _any_ nice level, + * if you go up 1 level, it's -10% CPU usage, if you go down 1 level + * it's +10% CPU usage. (to achieve that we use a multiplier of 1.25. + * If a task goes up by ~10% and another task goes down by ~10% then + * the relative distance between them is ~25%.) + */ +static const int prio_to_weight[40] = { + /* -20 */ 88761, 71755, 56483, 46273, 36291, + /* -15 */ 29154, 23254, 18705, 14949, 11916, + /* -10 */ 9548, 7620, 6100, 4904, 3906, + /* -5 */ 3121, 2501, 1991, 1586, 1277, + /* 0 */ 1024, 820, 655, 526, 423, + /* 5 */ 335, 272, 215, 172, 137, + /* 10 */ 110, 87, 70, 56, 45, + /* 15 */ 36, 29, 23, 18, 15, +}; + +/* + * Inverse (2^32/x) values of the prio_to_weight[] array, precalculated. + * + * In cases where the weight does not change often, we can use the + * precalculated inverse to speed up arithmetics by turning divisions + * into multiplications: + */ +static const u32 prio_to_wmult[40] = { + /* -20 */ 48388, 59856, 76040, 92818, 118348, + /* -15 */ 147320, 184698, 229616, 287308, 360437, + /* -10 */ 449829, 563644, 704093, 875809, 1099582, + /* -5 */ 1376151, 1717300, 2157191, 2708050, 3363326, + /* 0 */ 4194304, 5237765, 6557202, 8165337, 10153587, + /* 5 */ 12820798, 15790321, 19976592, 24970740, 31350126, + /* 10 */ 39045157, 49367440, 61356676, 76695844, 95443717, + /* 15 */ 119304647, 148102320, 186737708, 238609294, 286331153, +}; + +/* Time spent by the tasks of the cpu accounting group executing in ... */ +enum cpuacct_stat_index { + CPUACCT_STAT_USER, /* ... user mode */ + CPUACCT_STAT_SYSTEM, /* ... kernel mode */ + + CPUACCT_STAT_NSTATS, +}; + + +#define sched_class_highest (&stop_sched_class) +#define for_each_class(class) \ + for (class = sched_class_highest; class; class = class->next) + +extern const struct sched_class stop_sched_class; +extern const struct sched_class rt_sched_class; +extern const struct sched_class fair_sched_class; +extern const struct sched_class idle_sched_class; + + +#ifdef CONFIG_SMP + +extern void trigger_load_balance(struct rq *rq, int cpu); +extern void idle_balance(int this_cpu, struct rq *this_rq); + +#else /* CONFIG_SMP */ + +static inline void idle_balance(int cpu, struct rq *rq) +{ +} + +#endif + +extern void sysrq_sched_debug_show(void); +extern void sched_init_granularity(void); +extern void update_max_interval(void); +extern void update_group_power(struct sched_domain *sd, int cpu); +extern int update_runtime(struct notifier_block *nfb, unsigned long action, void *hcpu); +extern void init_sched_rt_class(void); +extern void init_sched_fair_class(void); + +extern void resched_task(struct task_struct *p); +extern void resched_cpu(int cpu); + +extern struct rt_bandwidth def_rt_bandwidth; +extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); + +extern void update_cpu_load(struct rq *this_rq); + +#ifdef CONFIG_CGROUP_CPUACCT +#include <linux/cgroup.h> +/* track cpu usage of a group of tasks and its child groups */ +struct cpuacct { + struct cgroup_subsys_state css; + /* cpuusage holds pointer to a u64-type object on every cpu */ + u64 __percpu *cpuusage; + struct kernel_cpustat __percpu *cpustat; +}; + +/* return cpu accounting group corresponding to this container */ +static inline struct cpuacct *cgroup_ca(struct cgroup *cgrp) +{ + return container_of(cgroup_subsys_state(cgrp, cpuacct_subsys_id), + struct cpuacct, css); +} + +/* return cpu accounting group to which this task belongs */ +static inline struct cpuacct *task_ca(struct task_struct *tsk) +{ + return container_of(task_subsys_state(tsk, cpuacct_subsys_id), + struct cpuacct, css); +} + +static inline struct cpuacct *parent_ca(struct cpuacct *ca) +{ + if (!ca || !ca->css.cgroup->parent) + return NULL; + return cgroup_ca(ca->css.cgroup->parent); +} + +extern void cpuacct_charge(struct task_struct *tsk, u64 cputime); +#else +static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {} +#endif + +static inline void inc_nr_running(struct rq *rq) +{ + rq->nr_running++; +} + +static inline void dec_nr_running(struct rq *rq) +{ + rq->nr_running--; +} + +extern void update_rq_clock(struct rq *rq); + +extern void activate_task(struct rq *rq, struct task_struct *p, int flags); +extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); + +extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags); + +extern const_debug unsigned int sysctl_sched_time_avg; +extern const_debug unsigned int sysctl_sched_nr_migrate; +extern const_debug unsigned int sysctl_sched_migration_cost; + +static inline u64 sched_avg_period(void) +{ + return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2; +} + +void calc_load_account_idle(struct rq *this_rq); + +#ifdef CONFIG_SCHED_HRTICK + +/* + * Use hrtick when: + * - enabled by features + * - hrtimer is actually high res + */ +static inline int hrtick_enabled(struct rq *rq) +{ + if (!sched_feat(HRTICK)) + return 0; + if (!cpu_active(cpu_of(rq))) + return 0; + return hrtimer_is_hres_active(&rq->hrtick_timer); +} + +void hrtick_start(struct rq *rq, u64 delay); + +#else + +static inline int hrtick_enabled(struct rq *rq) +{ + return 0; +} + +#endif /* CONFIG_SCHED_HRTICK */ + +#ifdef CONFIG_SMP +extern void sched_avg_update(struct rq *rq); +static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) +{ + rq->rt_avg += rt_delta; + sched_avg_update(rq); +} +#else +static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { } +static inline void sched_avg_update(struct rq *rq) { } +#endif + +extern void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period); + +#ifdef CONFIG_SMP +#ifdef CONFIG_PREEMPT + +static inline 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 + * invocations. This assures that the double_lock is acquired using the + * same underlying policy as the spinlock_t on this architecture, which + * reduces latency compared to the unfair variant below. However, it + * also adds more overhead and therefore may reduce throughput. + */ +static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) + __releases(this_rq->lock) + __acquires(busiest->lock) + __acquires(this_rq->lock) +{ + raw_spin_unlock(&this_rq->lock); + double_rq_lock(this_rq, busiest); + + return 1; +} + +#else +/* + * Unfair double_lock_balance: Optimizes throughput at the expense of + * latency by eliminating extra atomic operations when the locks are + * already in proper order on entry. This favors lower cpu-ids and will + * grant the double lock to lower cpus over higher ids under contention, + * regardless of entry order into the function. + */ +static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) + __releases(this_rq->lock) + __acquires(busiest->lock) + __acquires(this_rq->lock) +{ + int ret = 0; + + if (unlikely(!raw_spin_trylock(&busiest->lock))) { + if (busiest < this_rq) { + raw_spin_unlock(&this_rq->lock); + raw_spin_lock(&busiest->lock); + raw_spin_lock_nested(&this_rq->lock, + SINGLE_DEPTH_NESTING); + ret = 1; + } else + raw_spin_lock_nested(&busiest->lock, + SINGLE_DEPTH_NESTING); + } + return ret; +} + +#endif /* CONFIG_PREEMPT */ + +/* + * double_lock_balance - lock the busiest runqueue, this_rq is locked already. + */ +static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) +{ + if (unlikely(!irqs_disabled())) { + /* printk() doesn't work good under rq->lock */ + raw_spin_unlock(&this_rq->lock); + BUG_ON(1); + } + + return _double_lock_balance(this_rq, busiest); +} + +static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) + __releases(busiest->lock) +{ + raw_spin_unlock(&busiest->lock); + lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_); +} + +/* + * double_rq_lock - safely lock two runqueues + * + * Note this does not disable interrupts like task_rq_lock, + * you need to do so manually before calling. + */ +static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) + __acquires(rq1->lock) + __acquires(rq2->lock) +{ + BUG_ON(!irqs_disabled()); + if (rq1 == rq2) { + raw_spin_lock(&rq1->lock); + __acquire(rq2->lock); /* Fake it out ;) */ + } else { + if (rq1 < rq2) { + raw_spin_lock(&rq1->lock); + raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING); + } else { + raw_spin_lock(&rq2->lock); + raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING); + } + } +} + +/* + * double_rq_unlock - safely unlock two runqueues + * + * Note this does not restore interrupts like task_rq_unlock, + * you need to do so manually after calling. + */ +static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) + __releases(rq1->lock) + __releases(rq2->lock) +{ + raw_spin_unlock(&rq1->lock); + if (rq1 != rq2) + raw_spin_unlock(&rq2->lock); + else + __release(rq2->lock); +} + +#else /* CONFIG_SMP */ + +/* + * double_rq_lock - safely lock two runqueues + * + * Note this does not disable interrupts like task_rq_lock, + * you need to do so manually before calling. + */ +static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) + __acquires(rq1->lock) + __acquires(rq2->lock) +{ + BUG_ON(!irqs_disabled()); + BUG_ON(rq1 != rq2); + raw_spin_lock(&rq1->lock); + __acquire(rq2->lock); /* Fake it out ;) */ +} + +/* + * double_rq_unlock - safely unlock two runqueues + * + * Note this does not restore interrupts like task_rq_unlock, + * you need to do so manually after calling. + */ +static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) + __releases(rq1->lock) + __releases(rq2->lock) +{ + BUG_ON(rq1 != rq2); + raw_spin_unlock(&rq1->lock); + __release(rq2->lock); +} + +#endif + +extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); +extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq); +extern void print_cfs_stats(struct seq_file *m, int cpu); +extern void print_rt_stats(struct seq_file *m, int cpu); + +extern void init_cfs_rq(struct cfs_rq *cfs_rq); +extern void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq); +extern void unthrottle_offline_cfs_rqs(struct rq *rq); + +extern void account_cfs_bandwidth_used(int enabled, int was_enabled); + +#ifdef CONFIG_NO_HZ +enum rq_nohz_flag_bits { + NOHZ_TICK_STOPPED, + NOHZ_BALANCE_KICK, + NOHZ_IDLE, +}; + +#define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags) +#endif diff --git a/kernel/sched/stats.c b/kernel/sched/stats.c new file mode 100644 index 0000000..2a581ba --- /dev/null +++ b/kernel/sched/stats.c @@ -0,0 +1,111 @@ + +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/seq_file.h> +#include <linux/proc_fs.h> + +#include "sched.h" + +/* + * bump this up when changing the output format or the meaning of an existing + * format, so that tools can adapt (or abort) + */ +#define SCHEDSTAT_VERSION 15 + +static int show_schedstat(struct seq_file *seq, void *v) +{ + int cpu; + int mask_len = DIV_ROUND_UP(NR_CPUS, 32) * 9; + char *mask_str = kmalloc(mask_len, GFP_KERNEL); + + if (mask_str == NULL) + return -ENOMEM; + + seq_printf(seq, "version %d\n", SCHEDSTAT_VERSION); + seq_printf(seq, "timestamp %lu\n", jiffies); + for_each_online_cpu(cpu) { + struct rq *rq = cpu_rq(cpu); +#ifdef CONFIG_SMP + struct sched_domain *sd; + int dcount = 0; +#endif + + /* runqueue-specific stats */ + seq_printf(seq, + "cpu%d %u %u %u %u %u %u %llu %llu %lu", + cpu, rq->yld_count, + rq->sched_switch, rq->sched_count, rq->sched_goidle, + rq->ttwu_count, rq->ttwu_local, + rq->rq_cpu_time, + rq->rq_sched_info.run_delay, rq->rq_sched_info.pcount); + + seq_printf(seq, "\n"); + +#ifdef CONFIG_SMP + /* domain-specific stats */ + rcu_read_lock(); + for_each_domain(cpu, sd) { + enum cpu_idle_type itype; + + cpumask_scnprintf(mask_str, mask_len, + sched_domain_span(sd)); + seq_printf(seq, "domain%d %s", dcount++, mask_str); + for (itype = CPU_IDLE; itype < CPU_MAX_IDLE_TYPES; + itype++) { + seq_printf(seq, " %u %u %u %u %u %u %u %u", + sd->lb_count[itype], + sd->lb_balanced[itype], + sd->lb_failed[itype], + sd->lb_imbalance[itype], + sd->lb_gained[itype], + sd->lb_hot_gained[itype], + sd->lb_nobusyq[itype], + sd->lb_nobusyg[itype]); + } + seq_printf(seq, + " %u %u %u %u %u %u %u %u %u %u %u %u\n", + sd->alb_count, sd->alb_failed, sd->alb_pushed, + sd->sbe_count, sd->sbe_balanced, sd->sbe_pushed, + sd->sbf_count, sd->sbf_balanced, sd->sbf_pushed, + sd->ttwu_wake_remote, sd->ttwu_move_affine, + sd->ttwu_move_balance); + } + rcu_read_unlock(); +#endif + } + kfree(mask_str); + return 0; +} + +static int schedstat_open(struct inode *inode, struct file *file) +{ + unsigned int size = PAGE_SIZE * (1 + num_online_cpus() / 32); + char *buf = kmalloc(size, GFP_KERNEL); + struct seq_file *m; + int res; + + if (!buf) + return -ENOMEM; + res = single_open(file, show_schedstat, NULL); + if (!res) { + m = file->private_data; + m->buf = buf; + m->size = size; + } else + kfree(buf); + return res; +} + +static const struct file_operations proc_schedstat_operations = { + .open = schedstat_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static int __init proc_schedstat_init(void) +{ + proc_create("schedstat", 0, NULL, &proc_schedstat_operations); + return 0; +} +module_init(proc_schedstat_init); diff --git a/kernel/sched_stats.h b/kernel/sched/stats.h index 87f9e36..2ef90a5 100644 --- a/kernel/sched_stats.h +++ b/kernel/sched/stats.h @@ -1,108 +1,5 @@ #ifdef CONFIG_SCHEDSTATS -/* - * bump this up when changing the output format or the meaning of an existing - * format, so that tools can adapt (or abort) - */ -#define SCHEDSTAT_VERSION 15 - -static int show_schedstat(struct seq_file *seq, void *v) -{ - int cpu; - int mask_len = DIV_ROUND_UP(NR_CPUS, 32) * 9; - char *mask_str = kmalloc(mask_len, GFP_KERNEL); - - if (mask_str == NULL) - return -ENOMEM; - - seq_printf(seq, "version %d\n", SCHEDSTAT_VERSION); - seq_printf(seq, "timestamp %lu\n", jiffies); - for_each_online_cpu(cpu) { - struct rq *rq = cpu_rq(cpu); -#ifdef CONFIG_SMP - struct sched_domain *sd; - int dcount = 0; -#endif - - /* runqueue-specific stats */ - seq_printf(seq, - "cpu%d %u %u %u %u %u %u %llu %llu %lu", - cpu, rq->yld_count, - rq->sched_switch, rq->sched_count, rq->sched_goidle, - rq->ttwu_count, rq->ttwu_local, - rq->rq_cpu_time, - rq->rq_sched_info.run_delay, rq->rq_sched_info.pcount); - - seq_printf(seq, "\n"); - -#ifdef CONFIG_SMP - /* domain-specific stats */ - rcu_read_lock(); - for_each_domain(cpu, sd) { - enum cpu_idle_type itype; - - cpumask_scnprintf(mask_str, mask_len, - sched_domain_span(sd)); - seq_printf(seq, "domain%d %s", dcount++, mask_str); - for (itype = CPU_IDLE; itype < CPU_MAX_IDLE_TYPES; - itype++) { - seq_printf(seq, " %u %u %u %u %u %u %u %u", - sd->lb_count[itype], - sd->lb_balanced[itype], - sd->lb_failed[itype], - sd->lb_imbalance[itype], - sd->lb_gained[itype], - sd->lb_hot_gained[itype], - sd->lb_nobusyq[itype], - sd->lb_nobusyg[itype]); - } - seq_printf(seq, - " %u %u %u %u %u %u %u %u %u %u %u %u\n", - sd->alb_count, sd->alb_failed, sd->alb_pushed, - sd->sbe_count, sd->sbe_balanced, sd->sbe_pushed, - sd->sbf_count, sd->sbf_balanced, sd->sbf_pushed, - sd->ttwu_wake_remote, sd->ttwu_move_affine, - sd->ttwu_move_balance); - } - rcu_read_unlock(); -#endif - } - kfree(mask_str); - return 0; -} - -static int schedstat_open(struct inode *inode, struct file *file) -{ - unsigned int size = PAGE_SIZE * (1 + num_online_cpus() / 32); - char *buf = kmalloc(size, GFP_KERNEL); - struct seq_file *m; - int res; - - if (!buf) - return -ENOMEM; - res = single_open(file, show_schedstat, NULL); - if (!res) { - m = file->private_data; - m->buf = buf; - m->size = size; - } else - kfree(buf); - return res; -} - -static const struct file_operations proc_schedstat_operations = { - .open = schedstat_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; - -static int __init proc_schedstat_init(void) -{ - proc_create("schedstat", 0, NULL, &proc_schedstat_operations); - return 0; -} -module_init(proc_schedstat_init); /* * Expects runqueue lock to be held for atomicity of update @@ -283,8 +180,7 @@ static inline void account_group_user_time(struct task_struct *tsk, return; raw_spin_lock(&cputimer->lock); - cputimer->cputime.utime = - cputime_add(cputimer->cputime.utime, cputime); + cputimer->cputime.utime += cputime; raw_spin_unlock(&cputimer->lock); } @@ -307,8 +203,7 @@ static inline void account_group_system_time(struct task_struct *tsk, return; raw_spin_lock(&cputimer->lock); - cputimer->cputime.stime = - cputime_add(cputimer->cputime.stime, cputime); + cputimer->cputime.stime += cputime; raw_spin_unlock(&cputimer->lock); } diff --git a/kernel/sched_stoptask.c b/kernel/sched/stop_task.c index 8b44e7f..7b386e8 100644 --- a/kernel/sched_stoptask.c +++ b/kernel/sched/stop_task.c @@ -1,3 +1,5 @@ +#include "sched.h" + /* * stop-task scheduling class. * @@ -80,7 +82,7 @@ get_rr_interval_stop(struct rq *rq, struct task_struct *task) /* * Simple, special scheduling class for the per-CPU stop tasks: */ -static const struct sched_class stop_sched_class = { +const struct sched_class stop_sched_class = { .next = &rt_sched_class, .enqueue_task = enqueue_task_stop, diff --git a/kernel/signal.c b/kernel/signal.c index 2065515..c73c428 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -28,6 +28,7 @@ #include <linux/freezer.h> #include <linux/pid_namespace.h> #include <linux/nsproxy.h> +#include <linux/user_namespace.h> #define CREATE_TRACE_POINTS #include <trace/events/signal.h> @@ -1019,6 +1020,34 @@ static inline int legacy_queue(struct sigpending *signals, int sig) return (sig < SIGRTMIN) && sigismember(&signals->signal, sig); } +/* + * map the uid in struct cred into user namespace *ns + */ +static inline uid_t map_cred_ns(const struct cred *cred, + struct user_namespace *ns) +{ + return user_ns_map_uid(ns, cred, cred->uid); +} + +#ifdef CONFIG_USER_NS +static inline void userns_fixup_signal_uid(struct siginfo *info, struct task_struct *t) +{ + if (current_user_ns() == task_cred_xxx(t, user_ns)) + return; + + if (SI_FROMKERNEL(info)) + return; + + info->si_uid = user_ns_map_uid(task_cred_xxx(t, user_ns), + current_cred(), info->si_uid); +} +#else +static inline void userns_fixup_signal_uid(struct siginfo *info, struct task_struct *t) +{ + return; +} +#endif + static int __send_signal(int sig, struct siginfo *info, struct task_struct *t, int group, int from_ancestor_ns) { @@ -1088,6 +1117,9 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t, q->info.si_pid = 0; break; } + + userns_fixup_signal_uid(&q->info, t); + } else if (!is_si_special(info)) { if (sig >= SIGRTMIN && info->si_code != SI_USER) { /* @@ -1626,13 +1658,12 @@ bool do_notify_parent(struct task_struct *tsk, int sig) */ rcu_read_lock(); info.si_pid = task_pid_nr_ns(tsk, tsk->parent->nsproxy->pid_ns); - info.si_uid = __task_cred(tsk)->uid; + info.si_uid = map_cred_ns(__task_cred(tsk), + task_cred_xxx(tsk->parent, user_ns)); rcu_read_unlock(); - info.si_utime = cputime_to_clock_t(cputime_add(tsk->utime, - tsk->signal->utime)); - info.si_stime = cputime_to_clock_t(cputime_add(tsk->stime, - tsk->signal->stime)); + info.si_utime = cputime_to_clock_t(tsk->utime + tsk->signal->utime); + info.si_stime = cputime_to_clock_t(tsk->stime + tsk->signal->stime); info.si_status = tsk->exit_code & 0x7f; if (tsk->exit_code & 0x80) @@ -1711,7 +1742,8 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, */ rcu_read_lock(); info.si_pid = task_pid_nr_ns(tsk, parent->nsproxy->pid_ns); - info.si_uid = __task_cred(tsk)->uid; + info.si_uid = map_cred_ns(__task_cred(tsk), + task_cred_xxx(parent, user_ns)); rcu_read_unlock(); info.si_utime = cputime_to_clock_t(tsk->utime); @@ -2127,8 +2159,11 @@ static int ptrace_signal(int signr, siginfo_t *info, info->si_signo = signr; info->si_errno = 0; info->si_code = SI_USER; + rcu_read_lock(); info->si_pid = task_pid_vnr(current->parent); - info->si_uid = task_uid(current->parent); + info->si_uid = map_cred_ns(__task_cred(current->parent), + current_user_ns()); + rcu_read_unlock(); } /* If the (new) signal is now blocked, requeue it. */ @@ -2320,6 +2355,27 @@ relock: return signr; } +/** + * block_sigmask - add @ka's signal mask to current->blocked + * @ka: action for @signr + * @signr: signal that has been successfully delivered + * + * This function should be called when a signal has succesfully been + * delivered. It adds the mask of signals for @ka to current->blocked + * so that they are blocked during the execution of the signal + * handler. In addition, @signr will be blocked unless %SA_NODEFER is + * set in @ka->sa.sa_flags. + */ +void block_sigmask(struct k_sigaction *ka, int signr) +{ + sigset_t blocked; + + sigorsets(&blocked, ¤t->blocked, &ka->sa.sa_mask); + if (!(ka->sa.sa_flags & SA_NODEFER)) + sigaddset(&blocked, signr); + set_current_blocked(&blocked); +} + /* * It could be that complete_signal() picked us to notify about the * group-wide signal. Other threads should be notified now to take @@ -2357,8 +2413,15 @@ void exit_signals(struct task_struct *tsk) int group_stop = 0; sigset_t unblocked; + /* + * @tsk is about to have PF_EXITING set - lock out users which + * expect stable threadgroup. + */ + threadgroup_change_begin(tsk); + if (thread_group_empty(tsk) || signal_group_exit(tsk->signal)) { tsk->flags |= PF_EXITING; + threadgroup_change_end(tsk); return; } @@ -2368,6 +2431,9 @@ void exit_signals(struct task_struct *tsk) * see wants_signal(), do_signal_stop(). */ tsk->flags |= PF_EXITING; + + threadgroup_change_end(tsk); + if (!signal_pending(tsk)) goto out; diff --git a/kernel/softirq.c b/kernel/softirq.c index 2c71d91..4eb3a0f 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -347,12 +347,12 @@ void irq_exit(void) if (!in_interrupt() && local_softirq_pending()) invoke_softirq(); - rcu_irq_exit(); #ifdef CONFIG_NO_HZ /* Make sure that timer wheel updates are propagated */ if (idle_cpu(smp_processor_id()) && !in_interrupt() && !need_resched()) - tick_nohz_stop_sched_tick(0); + tick_nohz_irq_exit(); #endif + rcu_irq_exit(); preempt_enable_no_resched(); } diff --git a/kernel/sys.c b/kernel/sys.c index 481611f..4070153 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1605,7 +1605,7 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r) unsigned long maxrss = 0; memset((char *) r, 0, sizeof *r); - utime = stime = cputime_zero; + utime = stime = 0; if (who == RUSAGE_THREAD) { task_times(current, &utime, &stime); @@ -1635,8 +1635,8 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r) case RUSAGE_SELF: thread_group_times(p, &tgutime, &tgstime); - utime = cputime_add(utime, tgutime); - stime = cputime_add(stime, tgstime); + utime += tgutime; + stime += tgstime; r->ru_nvcsw += p->signal->nvcsw; r->ru_nivcsw += p->signal->nivcsw; r->ru_minflt += p->signal->min_flt; @@ -1692,6 +1692,124 @@ SYSCALL_DEFINE1(umask, int, mask) return mask; } +#ifdef CONFIG_CHECKPOINT_RESTORE +static int prctl_set_mm(int opt, unsigned long addr, + unsigned long arg4, unsigned long arg5) +{ + unsigned long rlim = rlimit(RLIMIT_DATA); + unsigned long vm_req_flags; + unsigned long vm_bad_flags; + struct vm_area_struct *vma; + int error = 0; + struct mm_struct *mm = current->mm; + + if (arg4 | arg5) + return -EINVAL; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (addr >= TASK_SIZE) + return -EINVAL; + + down_read(&mm->mmap_sem); + vma = find_vma(mm, addr); + + if (opt != PR_SET_MM_START_BRK && opt != PR_SET_MM_BRK) { + /* It must be existing VMA */ + if (!vma || vma->vm_start > addr) + goto out; + } + + error = -EINVAL; + switch (opt) { + case PR_SET_MM_START_CODE: + case PR_SET_MM_END_CODE: + vm_req_flags = VM_READ | VM_EXEC; + vm_bad_flags = VM_WRITE | VM_MAYSHARE; + + if ((vma->vm_flags & vm_req_flags) != vm_req_flags || + (vma->vm_flags & vm_bad_flags)) + goto out; + + if (opt == PR_SET_MM_START_CODE) + mm->start_code = addr; + else + mm->end_code = addr; + break; + + case PR_SET_MM_START_DATA: + case PR_SET_MM_END_DATA: + vm_req_flags = VM_READ | VM_WRITE; + vm_bad_flags = VM_EXEC | VM_MAYSHARE; + + if ((vma->vm_flags & vm_req_flags) != vm_req_flags || + (vma->vm_flags & vm_bad_flags)) + goto out; + + if (opt == PR_SET_MM_START_DATA) + mm->start_data = addr; + else + mm->end_data = addr; + break; + + case PR_SET_MM_START_STACK: + +#ifdef CONFIG_STACK_GROWSUP + vm_req_flags = VM_READ | VM_WRITE | VM_GROWSUP; +#else + vm_req_flags = VM_READ | VM_WRITE | VM_GROWSDOWN; +#endif + if ((vma->vm_flags & vm_req_flags) != vm_req_flags) + goto out; + + mm->start_stack = addr; + break; + + case PR_SET_MM_START_BRK: + if (addr <= mm->end_data) + goto out; + + if (rlim < RLIM_INFINITY && + (mm->brk - addr) + + (mm->end_data - mm->start_data) > rlim) + goto out; + + mm->start_brk = addr; + break; + + case PR_SET_MM_BRK: + if (addr <= mm->end_data) + goto out; + + if (rlim < RLIM_INFINITY && + (addr - mm->start_brk) + + (mm->end_data - mm->start_data) > rlim) + goto out; + + mm->brk = addr; + break; + + default: + error = -EINVAL; + goto out; + } + + error = 0; + +out: + up_read(&mm->mmap_sem); + + return error; +} +#else /* CONFIG_CHECKPOINT_RESTORE */ +static int prctl_set_mm(int opt, unsigned long addr, + unsigned long arg4, unsigned long arg5) +{ + return -EINVAL; +} +#endif + SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, unsigned long, arg4, unsigned long, arg5) { @@ -1841,6 +1959,9 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, else error = PR_MCE_KILL_DEFAULT; break; + case PR_SET_MM: + error = prctl_set_mm(arg2, arg3, arg4, arg5); + break; default: error = -EINVAL; break; diff --git a/kernel/sysctl.c b/kernel/sysctl.c index ae27196..f487f25 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -803,6 +803,15 @@ static struct ctl_table kern_table[] = { .mode = 0644, .proc_handler = proc_dointvec, }, +#ifdef CONFIG_DEBUG_STACKOVERFLOW + { + .procname = "panic_on_stackoverflow", + .data = &sysctl_panic_on_stackoverflow, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, +#endif { .procname = "bootloader_type", .data = &bootloader_type, diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig index b26c2228..2cf9cc7 100644 --- a/kernel/time/Kconfig +++ b/kernel/time/Kconfig @@ -25,7 +25,7 @@ config HIGH_RES_TIMERS config GENERIC_CLOCKEVENTS_BUILD bool default y - depends on GENERIC_CLOCKEVENTS || GENERIC_CLOCKEVENTS_MIGR + depends on GENERIC_CLOCKEVENTS config GENERIC_CLOCKEVENTS_MIN_ADJUST bool diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index 1ecd6ba..9cd928f 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -17,7 +17,6 @@ #include <linux/module.h> #include <linux/notifier.h> #include <linux/smp.h> -#include <linux/sysdev.h> #include "tick-internal.h" diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index d3ad022..a45ca16 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -23,8 +23,8 @@ * o Allow clocksource drivers to be unregistered */ +#include <linux/device.h> #include <linux/clocksource.h> -#include <linux/sysdev.h> #include <linux/init.h> #include <linux/module.h> #include <linux/sched.h> /* for spin_unlock_irq() using preempt_count() m68k */ @@ -796,8 +796,8 @@ EXPORT_SYMBOL(clocksource_unregister); * Provides sysfs interface for listing current clocksource. */ static ssize_t -sysfs_show_current_clocksources(struct sys_device *dev, - struct sysdev_attribute *attr, char *buf) +sysfs_show_current_clocksources(struct device *dev, + struct device_attribute *attr, char *buf) { ssize_t count = 0; @@ -818,8 +818,8 @@ sysfs_show_current_clocksources(struct sys_device *dev, * Takes input from sysfs interface for manually overriding the default * clocksource selection. */ -static ssize_t sysfs_override_clocksource(struct sys_device *dev, - struct sysdev_attribute *attr, +static ssize_t sysfs_override_clocksource(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) { size_t ret = count; @@ -853,8 +853,8 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev, * Provides sysfs interface for listing registered clocksources */ static ssize_t -sysfs_show_available_clocksources(struct sys_device *dev, - struct sysdev_attribute *attr, +sysfs_show_available_clocksources(struct device *dev, + struct device_attribute *attr, char *buf) { struct clocksource *src; @@ -883,35 +883,36 @@ sysfs_show_available_clocksources(struct sys_device *dev, /* * Sysfs setup bits: */ -static SYSDEV_ATTR(current_clocksource, 0644, sysfs_show_current_clocksources, +static DEVICE_ATTR(current_clocksource, 0644, sysfs_show_current_clocksources, sysfs_override_clocksource); -static SYSDEV_ATTR(available_clocksource, 0444, +static DEVICE_ATTR(available_clocksource, 0444, sysfs_show_available_clocksources, NULL); -static struct sysdev_class clocksource_sysclass = { +static struct bus_type clocksource_subsys = { .name = "clocksource", + .dev_name = "clocksource", }; -static struct sys_device device_clocksource = { +static struct device device_clocksource = { .id = 0, - .cls = &clocksource_sysclass, + .bus = &clocksource_subsys, }; static int __init init_clocksource_sysfs(void) { - int error = sysdev_class_register(&clocksource_sysclass); + int error = subsys_system_register(&clocksource_subsys, NULL); if (!error) - error = sysdev_register(&device_clocksource); + error = device_register(&device_clocksource); if (!error) - error = sysdev_create_file( + error = device_create_file( &device_clocksource, - &attr_current_clocksource); + &dev_attr_current_clocksource); if (!error) - error = sysdev_create_file( + error = device_create_file( &device_clocksource, - &attr_available_clocksource); + &dev_attr_available_clocksource); return error; } diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 4042064..7656642 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -275,42 +275,17 @@ u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time) } EXPORT_SYMBOL_GPL(get_cpu_iowait_time_us); -/** - * tick_nohz_stop_sched_tick - stop the idle tick from the idle task - * - * When the next event is more than a tick into the future, stop the idle tick - * Called either from the idle loop or from irq_exit() when an idle period was - * just interrupted by an interrupt which did not cause a reschedule. - */ -void tick_nohz_stop_sched_tick(int inidle) +static void tick_nohz_stop_sched_tick(struct tick_sched *ts) { - unsigned long seq, last_jiffies, next_jiffies, delta_jiffies, flags; - struct tick_sched *ts; + unsigned long seq, last_jiffies, next_jiffies, delta_jiffies; ktime_t last_update, expires, now; struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev; u64 time_delta; int cpu; - local_irq_save(flags); - cpu = smp_processor_id(); ts = &per_cpu(tick_cpu_sched, cpu); - /* - * Call to tick_nohz_start_idle stops the last_update_time from being - * updated. Thus, it must not be called in the event we are called from - * irq_exit() with the prior state different than idle. - */ - if (!inidle && !ts->inidle) - goto end; - - /* - * Set ts->inidle unconditionally. Even if the system did not - * switch to NOHZ mode the cpu frequency governers rely on the - * update of the idle time accounting in tick_nohz_start_idle(). - */ - ts->inidle = 1; - now = tick_nohz_start_idle(cpu, ts); /* @@ -326,10 +301,10 @@ void tick_nohz_stop_sched_tick(int inidle) } if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE)) - goto end; + return; if (need_resched()) - goto end; + return; if (unlikely(local_softirq_pending() && cpu_online(cpu))) { static int ratelimit; @@ -339,7 +314,7 @@ void tick_nohz_stop_sched_tick(int inidle) (unsigned int) local_softirq_pending()); ratelimit++; } - goto end; + return; } ts->idle_calls++; @@ -434,7 +409,6 @@ void tick_nohz_stop_sched_tick(int inidle) ts->idle_tick = hrtimer_get_expires(&ts->sched_timer); ts->tick_stopped = 1; ts->idle_jiffies = last_jiffies; - rcu_enter_nohz(); } ts->idle_sleeps++; @@ -472,8 +446,64 @@ out: ts->next_jiffies = next_jiffies; ts->last_jiffies = last_jiffies; ts->sleep_length = ktime_sub(dev->next_event, now); -end: - local_irq_restore(flags); +} + +/** + * tick_nohz_idle_enter - stop the idle tick from the idle task + * + * When the next event is more than a tick into the future, stop the idle tick + * Called when we start the idle loop. + * + * The arch is responsible of calling: + * + * - rcu_idle_enter() after its last use of RCU before the CPU is put + * to sleep. + * - rcu_idle_exit() before the first use of RCU after the CPU is woken up. + */ +void tick_nohz_idle_enter(void) +{ + struct tick_sched *ts; + + WARN_ON_ONCE(irqs_disabled()); + + /* + * Update the idle state in the scheduler domain hierarchy + * when tick_nohz_stop_sched_tick() is called from the idle loop. + * State will be updated to busy during the first busy tick after + * exiting idle. + */ + set_cpu_sd_state_idle(); + + local_irq_disable(); + + ts = &__get_cpu_var(tick_cpu_sched); + /* + * set ts->inidle unconditionally. even if the system did not + * switch to nohz mode the cpu frequency governers rely on the + * update of the idle time accounting in tick_nohz_start_idle(). + */ + ts->inidle = 1; + tick_nohz_stop_sched_tick(ts); + + local_irq_enable(); +} + +/** + * tick_nohz_irq_exit - update next tick event from interrupt exit + * + * When an interrupt fires while we are idle and it doesn't cause + * a reschedule, it may still add, modify or delete a timer, enqueue + * an RCU callback, etc... + * So we need to re-calculate and reprogram the next tick event. + */ +void tick_nohz_irq_exit(void) +{ + struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched); + + if (!ts->inidle) + return; + + tick_nohz_stop_sched_tick(ts); } /** @@ -515,11 +545,13 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now) } /** - * tick_nohz_restart_sched_tick - restart the idle tick from the idle task + * tick_nohz_idle_exit - restart the idle tick from the idle task * * Restart the idle tick when the CPU is woken up from idle + * This also exit the RCU extended quiescent state. The CPU + * can use RCU again after this function is called. */ -void tick_nohz_restart_sched_tick(void) +void tick_nohz_idle_exit(void) { int cpu = smp_processor_id(); struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); @@ -529,6 +561,7 @@ void tick_nohz_restart_sched_tick(void) ktime_t now; local_irq_disable(); + if (ts->idle_active || (ts->inidle && ts->tick_stopped)) now = ktime_get(); @@ -543,8 +576,6 @@ void tick_nohz_restart_sched_tick(void) ts->inidle = 0; - rcu_exit_nohz(); - /* Update jiffies first */ select_nohz_load_balancer(0); tick_do_update_jiffies64(now); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 2378413..0c63581 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -131,7 +131,7 @@ static inline s64 timekeeping_get_ns_raw(void) /* 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 delta convert to nanoseconds. */ return clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift); } @@ -813,11 +813,11 @@ static void timekeeping_adjust(s64 offset) * First we shift it down from NTP_SHIFT to clocksource->shifted nsecs. * * Note we subtract one in the shift, so that error is really error*2. - * This "saves" dividing(shifting) intererval twice, but keeps the - * (error > interval) comparision as still measuring if error is + * This "saves" dividing(shifting) interval twice, but keeps the + * (error > interval) comparison as still measuring if error is * larger then half an interval. * - * Note: It does not "save" on aggrivation when reading the code. + * Note: It does not "save" on aggravation when reading the code. */ error = timekeeper.ntp_error >> (timekeeper.ntp_error_shift - 1); if (error > interval) { @@ -833,7 +833,7 @@ static void timekeeping_adjust(s64 offset) * nanosecond, and store the amount rounded up into * the error. This causes the likely below to be unlikely. * - * The properfix is to avoid rounding up by using + * The proper fix is to avoid rounding up by using * the high precision timekeeper.xtime_nsec instead of * xtime.tv_nsec everywhere. Fixing this will take some * time. diff --git a/kernel/timer.c b/kernel/timer.c index 9c3c62b..a297ffc 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -427,6 +427,12 @@ static int timer_fixup_init(void *addr, enum debug_obj_state state) } } +/* Stub timer callback for improperly used timers. */ +static void stub_timer(unsigned long data) +{ + WARN_ON(1); +} + /* * fixup_activate is called when: * - an active object is activated @@ -450,7 +456,8 @@ static int timer_fixup_activate(void *addr, enum debug_obj_state state) debug_object_activate(timer, &timer_debug_descr); return 0; } else { - WARN_ON_ONCE(1); + setup_timer(timer, stub_timer, 0); + return 1; } return 0; @@ -480,12 +487,40 @@ static int timer_fixup_free(void *addr, enum debug_obj_state state) } } +/* + * fixup_assert_init is called when: + * - an untracked/uninit-ed object is found + */ +static int timer_fixup_assert_init(void *addr, enum debug_obj_state state) +{ + struct timer_list *timer = addr; + + switch (state) { + case ODEBUG_STATE_NOTAVAILABLE: + if (timer->entry.prev == TIMER_ENTRY_STATIC) { + /* + * This is not really a fixup. The timer was + * statically initialized. We just make sure that it + * is tracked in the object tracker. + */ + debug_object_init(timer, &timer_debug_descr); + return 0; + } else { + setup_timer(timer, stub_timer, 0); + return 1; + } + default: + return 0; + } +} + static struct debug_obj_descr timer_debug_descr = { - .name = "timer_list", - .debug_hint = timer_debug_hint, - .fixup_init = timer_fixup_init, - .fixup_activate = timer_fixup_activate, - .fixup_free = timer_fixup_free, + .name = "timer_list", + .debug_hint = timer_debug_hint, + .fixup_init = timer_fixup_init, + .fixup_activate = timer_fixup_activate, + .fixup_free = timer_fixup_free, + .fixup_assert_init = timer_fixup_assert_init, }; static inline void debug_timer_init(struct timer_list *timer) @@ -508,6 +543,11 @@ static inline void debug_timer_free(struct timer_list *timer) debug_object_free(timer, &timer_debug_descr); } +static inline void debug_timer_assert_init(struct timer_list *timer) +{ + debug_object_assert_init(timer, &timer_debug_descr); +} + static void __init_timer(struct timer_list *timer, const char *name, struct lock_class_key *key); @@ -531,6 +571,7 @@ EXPORT_SYMBOL_GPL(destroy_timer_on_stack); static inline void debug_timer_init(struct timer_list *timer) { } static inline void debug_timer_activate(struct timer_list *timer) { } static inline void debug_timer_deactivate(struct timer_list *timer) { } +static inline void debug_timer_assert_init(struct timer_list *timer) { } #endif static inline void debug_init(struct timer_list *timer) @@ -552,6 +593,11 @@ static inline void debug_deactivate(struct timer_list *timer) trace_timer_cancel(timer); } +static inline void debug_assert_init(struct timer_list *timer) +{ + debug_timer_assert_init(timer); +} + static void __init_timer(struct timer_list *timer, const char *name, struct lock_class_key *key) @@ -902,6 +948,8 @@ int del_timer(struct timer_list *timer) unsigned long flags; int ret = 0; + debug_assert_init(timer); + timer_stats_timer_clear_start_info(timer); if (timer_pending(timer)) { base = lock_timer_base(timer, &flags); @@ -932,6 +980,8 @@ int try_to_del_timer_sync(struct timer_list *timer) unsigned long flags; int ret = -1; + debug_assert_init(timer); + base = lock_timer_base(timer, &flags); if (base->running_timer == timer) diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index 16fc34a..cdea7b5 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -402,7 +402,7 @@ static int blk_remove_buf_file_callback(struct dentry *dentry) static struct dentry *blk_create_buf_file_callback(const char *filename, struct dentry *parent, - int mode, + umode_t mode, struct rchan_buf *buf, int *is_global) { diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 7392070..a3f1bc5 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4438,7 +4438,7 @@ static const struct file_operations trace_options_core_fops = { }; struct dentry *trace_create_file(const char *name, - mode_t mode, + umode_t mode, struct dentry *parent, void *data, const struct file_operations *fops) @@ -4828,6 +4828,7 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { __ftrace_dump(true, oops_dump_mode); } +EXPORT_SYMBOL_GPL(ftrace_dump); __init static int tracer_alloc_buffers(void) { diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 2c26574..b93ecba 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -312,7 +312,7 @@ void tracing_reset_current(int cpu); void tracing_reset_current_online_cpus(void); int tracing_open_generic(struct inode *inode, struct file *filp); struct dentry *trace_create_file(const char *name, - mode_t mode, + umode_t mode, struct dentry *parent, void *data, const struct file_operations *fops); diff --git a/kernel/tsacct.c b/kernel/tsacct.c index 5bbfac8..23b4d78 100644 --- a/kernel/tsacct.c +++ b/kernel/tsacct.c @@ -127,7 +127,7 @@ void acct_update_integrals(struct task_struct *tsk) local_irq_save(flags); time = tsk->stime + tsk->utime; - dtime = cputime_sub(time, tsk->acct_timexpd); + dtime = time - tsk->acct_timexpd; jiffies_to_timeval(cputime_to_jiffies(dtime), &value); delta = value.tv_sec; delta = delta * USEC_PER_SEC + value.tv_usec; diff --git a/kernel/wait.c b/kernel/wait.c index 26fa779..7fdd9ea 100644 --- a/kernel/wait.c +++ b/kernel/wait.c @@ -10,10 +10,10 @@ #include <linux/wait.h> #include <linux/hash.h> -void __init_waitqueue_head(wait_queue_head_t *q, struct lock_class_key *key) +void __init_waitqueue_head(wait_queue_head_t *q, const char *name, struct lock_class_key *key) { spin_lock_init(&q->lock); - lockdep_set_class(&q->lock, key); + lockdep_set_class_and_name(&q->lock, key, name); INIT_LIST_HEAD(&q->task_list); } diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 42fa9ad..bec7b5b 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -242,10 +242,10 @@ struct workqueue_struct { int nr_drainers; /* W: drain in progress */ int saved_max_active; /* W: saved cwq max_active */ - const char *name; /* I: workqueue name */ #ifdef CONFIG_LOCKDEP struct lockdep_map lockdep_map; #endif + char name[]; /* I: workqueue name */ }; struct workqueue_struct *system_wq __read_mostly; @@ -2954,14 +2954,29 @@ static int wq_clamp_max_active(int max_active, unsigned int flags, return clamp_val(max_active, 1, lim); } -struct workqueue_struct *__alloc_workqueue_key(const char *name, +struct workqueue_struct *__alloc_workqueue_key(const char *fmt, unsigned int flags, int max_active, struct lock_class_key *key, - const char *lock_name) + const char *lock_name, ...) { + va_list args, args1; struct workqueue_struct *wq; unsigned int cpu; + size_t namelen; + + /* determine namelen, allocate wq and format name */ + va_start(args, lock_name); + va_copy(args1, args); + namelen = vsnprintf(NULL, 0, fmt, args) + 1; + + wq = kzalloc(sizeof(*wq) + namelen, GFP_KERNEL); + if (!wq) + goto err; + + vsnprintf(wq->name, namelen, fmt, args1); + va_end(args); + va_end(args1); /* * Workqueues which may be used during memory reclaim should @@ -2978,12 +2993,9 @@ struct workqueue_struct *__alloc_workqueue_key(const char *name, flags |= WQ_HIGHPRI; max_active = max_active ?: WQ_DFL_ACTIVE; - max_active = wq_clamp_max_active(max_active, flags, name); - - wq = kzalloc(sizeof(*wq), GFP_KERNEL); - if (!wq) - goto err; + max_active = wq_clamp_max_active(max_active, flags, wq->name); + /* init wq */ wq->flags = flags; wq->saved_max_active = max_active; mutex_init(&wq->flush_mutex); @@ -2991,7 +3003,6 @@ struct workqueue_struct *__alloc_workqueue_key(const char *name, INIT_LIST_HEAD(&wq->flusher_queue); INIT_LIST_HEAD(&wq->flusher_overflow); - wq->name = name; lockdep_init_map(&wq->lockdep_map, lock_name, key, 0); INIT_LIST_HEAD(&wq->list); @@ -3020,7 +3031,8 @@ struct workqueue_struct *__alloc_workqueue_key(const char *name, if (!rescuer) goto err; - rescuer->task = kthread_create(rescuer_thread, wq, "%s", name); + rescuer->task = kthread_create(rescuer_thread, wq, "%s", + wq->name); if (IS_ERR(rescuer->task)) goto err; |
