diff options
author | Ingo Molnar <mingo@elte.hu> | 2009-01-11 03:41:39 +0100 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2009-01-11 03:41:39 +0100 |
commit | abede81c4fb2e3b85d8760f25e3da39d2c69a134 (patch) | |
tree | 26c893ec108d837eb9171d678c55a1cea7b22af4 /kernel | |
parent | c9d557c19f94df42db78d4a5de4d25feee694bad (diff) | |
parent | c59765042f53a79a7a65585042ff463b69cb248c (diff) | |
download | op-kernel-dev-abede81c4fb2e3b85d8760f25e3da39d2c69a134.zip op-kernel-dev-abede81c4fb2e3b85d8760f25e3da39d2c69a134.tar.gz |
Merge commit 'v2.6.29-rc1' into core/urgent
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/Makefile | 3 | ||||
-rw-r--r-- | kernel/async.c | 335 | ||||
-rw-r--r-- | kernel/cgroup.c | 276 | ||||
-rw-r--r-- | kernel/cpuset.c | 251 | ||||
-rw-r--r-- | kernel/cred.c | 5 | ||||
-rw-r--r-- | kernel/fork.c | 8 | ||||
-rw-r--r-- | kernel/irq/autoprobe.c | 5 | ||||
-rw-r--r-- | kernel/module.c | 2 | ||||
-rw-r--r-- | kernel/ns_cgroup.c | 2 | ||||
-rw-r--r-- | kernel/pid.c | 6 | ||||
-rw-r--r-- | kernel/power/disk.c | 6 | ||||
-rw-r--r-- | kernel/power/snapshot.c | 370 | ||||
-rw-r--r-- | kernel/power/swsusp.c | 122 | ||||
-rw-r--r-- | kernel/res_counter.c | 44 | ||||
-rw-r--r-- | kernel/resource.c | 61 | ||||
-rw-r--r-- | kernel/sched.c | 5 | ||||
-rw-r--r-- | kernel/sched_fair.c | 2 | ||||
-rw-r--r-- | kernel/sysctl.c | 14 | ||||
-rw-r--r-- | kernel/trace/ring_buffer.c | 8 |
19 files changed, 1129 insertions, 396 deletions
diff --git a/kernel/Makefile b/kernel/Makefile index e1c5bf3..2921d90 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -9,7 +9,8 @@ obj-y = sched.o fork.o exec_domain.o panic.o printk.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 pm_qos_params.o sched_clock.o cred.o + notifier.o ksysfs.o pm_qos_params.o sched_clock.o cred.o \ + async.o ifdef CONFIG_FUNCTION_TRACER # Do not trace debug files and internal ftrace files diff --git a/kernel/async.c b/kernel/async.c new file mode 100644 index 0000000..f286e9f --- /dev/null +++ b/kernel/async.c @@ -0,0 +1,335 @@ +/* + * async.c: Asynchronous function calls for boot performance + * + * (C) Copyright 2009 Intel Corporation + * Author: Arjan van de Ven <arjan@linux.intel.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; version 2 + * of the License. + */ + + +/* + +Goals and Theory of Operation + +The primary goal of this feature is to reduce the kernel boot time, +by doing various independent hardware delays and discovery operations +decoupled and not strictly serialized. + +More specifically, the asynchronous function call concept allows +certain operations (primarily during system boot) to happen +asynchronously, out of order, while these operations still +have their externally visible parts happen sequentially and in-order. +(not unlike how out-of-order CPUs retire their instructions in order) + +Key to the asynchronous function call implementation is the concept of +a "sequence cookie" (which, although it has an abstracted type, can be +thought of as a monotonically incrementing number). + +The async core will assign each scheduled event such a sequence cookie and +pass this to the called functions. + +The asynchronously called function should before doing a globally visible +operation, such as registering device numbers, call the +async_synchronize_cookie() function and pass in its own cookie. The +async_synchronize_cookie() function will make sure that all asynchronous +operations that were scheduled prior to the operation corresponding with the +cookie have completed. + +Subsystem/driver initialization code that scheduled asynchronous probe +functions, but which shares global resources with other drivers/subsystems +that do not use the asynchronous call feature, need to do a full +synchronization with the async_synchronize_full() function, before returning +from their init function. This is to maintain strict ordering between the +asynchronous and synchronous parts of the kernel. + +*/ + +#include <linux/async.h> +#include <linux/module.h> +#include <linux/wait.h> +#include <linux/sched.h> +#include <linux/init.h> +#include <linux/kthread.h> +#include <asm/atomic.h> + +static async_cookie_t next_cookie = 1; + +#define MAX_THREADS 256 +#define MAX_WORK 32768 + +static LIST_HEAD(async_pending); +static LIST_HEAD(async_running); +static DEFINE_SPINLOCK(async_lock); + +static int async_enabled = 0; + +struct async_entry { + struct list_head list; + async_cookie_t cookie; + async_func_ptr *func; + void *data; + struct list_head *running; +}; + +static DECLARE_WAIT_QUEUE_HEAD(async_done); +static DECLARE_WAIT_QUEUE_HEAD(async_new); + +static atomic_t entry_count; +static atomic_t thread_count; + +extern int initcall_debug; + + +/* + * MUST be called with the lock held! + */ +static async_cookie_t __lowest_in_progress(struct list_head *running) +{ + struct async_entry *entry; + if (!list_empty(&async_pending)) { + entry = list_first_entry(&async_pending, + struct async_entry, list); + return entry->cookie; + } else if (!list_empty(running)) { + entry = list_first_entry(running, + struct async_entry, list); + return entry->cookie; + } else { + /* nothing in progress... next_cookie is "infinity" */ + return next_cookie; + } + +} +/* + * pick the first pending entry and run it + */ +static void run_one_entry(void) +{ + unsigned long flags; + struct async_entry *entry; + ktime_t calltime, delta, rettime; + + /* 1) pick one task from the pending queue */ + + spin_lock_irqsave(&async_lock, flags); + if (list_empty(&async_pending)) + goto out; + entry = list_first_entry(&async_pending, struct async_entry, list); + + /* 2) move it to the running queue */ + list_del(&entry->list); + list_add_tail(&entry->list, &async_running); + spin_unlock_irqrestore(&async_lock, flags); + + /* 3) run it (and print duration)*/ + if (initcall_debug && system_state == SYSTEM_BOOTING) { + printk("calling %lli_%pF @ %i\n", entry->cookie, entry->func, task_pid_nr(current)); + calltime = ktime_get(); + } + entry->func(entry->data, entry->cookie); + if (initcall_debug && system_state == SYSTEM_BOOTING) { + rettime = ktime_get(); + delta = ktime_sub(rettime, calltime); + printk("initcall %lli_%pF returned 0 after %lld usecs\n", entry->cookie, + entry->func, ktime_to_ns(delta) >> 10); + } + + /* 4) remove it from the running queue */ + spin_lock_irqsave(&async_lock, flags); + list_del(&entry->list); + + /* 5) free the entry */ + kfree(entry); + atomic_dec(&entry_count); + + spin_unlock_irqrestore(&async_lock, flags); + + /* 6) wake up any waiters. */ + wake_up(&async_done); + return; + +out: + spin_unlock_irqrestore(&async_lock, flags); +} + + +static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct list_head *running) +{ + struct async_entry *entry; + unsigned long flags; + async_cookie_t newcookie; + + + /* allow irq-off callers */ + entry = kzalloc(sizeof(struct async_entry), GFP_ATOMIC); + + /* + * If we're out of memory or if there's too much work + * pending already, we execute synchronously. + */ + if (!async_enabled || !entry || atomic_read(&entry_count) > MAX_WORK) { + kfree(entry); + spin_lock_irqsave(&async_lock, flags); + newcookie = next_cookie++; + spin_unlock_irqrestore(&async_lock, flags); + + /* low on memory.. run synchronously */ + ptr(data, newcookie); + return newcookie; + } + entry->func = ptr; + entry->data = data; + entry->running = running; + + spin_lock_irqsave(&async_lock, flags); + newcookie = entry->cookie = next_cookie++; + list_add_tail(&entry->list, &async_pending); + atomic_inc(&entry_count); + spin_unlock_irqrestore(&async_lock, flags); + wake_up(&async_new); + return newcookie; +} + +async_cookie_t async_schedule(async_func_ptr *ptr, void *data) +{ + return __async_schedule(ptr, data, &async_pending); +} +EXPORT_SYMBOL_GPL(async_schedule); + +async_cookie_t async_schedule_special(async_func_ptr *ptr, void *data, struct list_head *running) +{ + return __async_schedule(ptr, data, running); +} +EXPORT_SYMBOL_GPL(async_schedule_special); + +void async_synchronize_full(void) +{ + do { + async_synchronize_cookie(next_cookie); + } while (!list_empty(&async_running) || !list_empty(&async_pending)); +} +EXPORT_SYMBOL_GPL(async_synchronize_full); + +void async_synchronize_full_special(struct list_head *list) +{ + async_synchronize_cookie_special(next_cookie, list); +} +EXPORT_SYMBOL_GPL(async_synchronize_full_special); + +void async_synchronize_cookie_special(async_cookie_t cookie, struct list_head *running) +{ + ktime_t starttime, delta, endtime; + + if (initcall_debug && system_state == SYSTEM_BOOTING) { + printk("async_waiting @ %i\n", task_pid_nr(current)); + starttime = ktime_get(); + } + + wait_event(async_done, __lowest_in_progress(running) >= cookie); + + if (initcall_debug && system_state == SYSTEM_BOOTING) { + endtime = ktime_get(); + delta = ktime_sub(endtime, starttime); + + printk("async_continuing @ %i after %lli usec\n", + task_pid_nr(current), ktime_to_ns(delta) >> 10); + } +} +EXPORT_SYMBOL_GPL(async_synchronize_cookie_special); + +void async_synchronize_cookie(async_cookie_t cookie) +{ + async_synchronize_cookie_special(cookie, &async_running); +} +EXPORT_SYMBOL_GPL(async_synchronize_cookie); + + +static int async_thread(void *unused) +{ + DECLARE_WAITQUEUE(wq, current); + add_wait_queue(&async_new, &wq); + + while (!kthread_should_stop()) { + int ret = HZ; + set_current_state(TASK_INTERRUPTIBLE); + /* + * check the list head without lock.. false positives + * are dealt with inside run_one_entry() while holding + * the lock. + */ + rmb(); + if (!list_empty(&async_pending)) + run_one_entry(); + else + ret = schedule_timeout(HZ); + + if (ret == 0) { + /* + * we timed out, this means we as thread are redundant. + * we sign off and die, but we to avoid any races there + * is a last-straw check to see if work snuck in. + */ + atomic_dec(&thread_count); + wmb(); /* manager must see our departure first */ + if (list_empty(&async_pending)) + break; + /* + * woops work came in between us timing out and us + * signing off; we need to stay alive and keep working. + */ + atomic_inc(&thread_count); + } + } + remove_wait_queue(&async_new, &wq); + + return 0; +} + +static int async_manager_thread(void *unused) +{ + DECLARE_WAITQUEUE(wq, current); + add_wait_queue(&async_new, &wq); + + while (!kthread_should_stop()) { + int tc, ec; + + set_current_state(TASK_INTERRUPTIBLE); + + tc = atomic_read(&thread_count); + rmb(); + ec = atomic_read(&entry_count); + + while (tc < ec && tc < MAX_THREADS) { + kthread_run(async_thread, NULL, "async/%i", tc); + atomic_inc(&thread_count); + tc++; + } + + schedule(); + } + remove_wait_queue(&async_new, &wq); + + return 0; +} + +static int __init async_init(void) +{ + if (async_enabled) + kthread_run(async_manager_thread, NULL, "async/mgr"); + return 0; +} + +static int __init setup_async(char *str) +{ + async_enabled = 1; + return 1; +} + +__setup("fastboot", setup_async); + + +core_initcall(async_init); diff --git a/kernel/cgroup.c b/kernel/cgroup.c index f221446..c298310 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -84,7 +84,7 @@ struct cgroupfs_root { /* Tracks how many cgroups are currently defined in hierarchy.*/ int number_of_cgroups; - /* A list running through the mounted hierarchies */ + /* A list running through the active hierarchies */ struct list_head root_list; /* Hierarchy-specific flags */ @@ -148,8 +148,8 @@ static int notify_on_release(const struct cgroup *cgrp) #define for_each_subsys(_root, _ss) \ list_for_each_entry(_ss, &_root->subsys_list, sibling) -/* for_each_root() allows you to iterate across the active hierarchies */ -#define for_each_root(_root) \ +/* for_each_active_root() allows you to iterate across the active hierarchies */ +#define for_each_active_root(_root) \ list_for_each_entry(_root, &roots, root_list) /* the list of cgroups eligible for automatic release. Protected by @@ -271,7 +271,7 @@ static void __put_css_set(struct css_set *cg, int taskexit) rcu_read_lock(); for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) { - struct cgroup *cgrp = cg->subsys[i]->cgroup; + struct cgroup *cgrp = rcu_dereference(cg->subsys[i]->cgroup); if (atomic_dec_and_test(&cgrp->count) && notify_on_release(cgrp)) { if (taskexit) @@ -384,6 +384,25 @@ static int allocate_cg_links(int count, struct list_head *tmp) return 0; } +/** + * link_css_set - a helper function to link a css_set to a cgroup + * @tmp_cg_links: cg_cgroup_link objects allocated by allocate_cg_links() + * @cg: the css_set to be linked + * @cgrp: the destination cgroup + */ +static void link_css_set(struct list_head *tmp_cg_links, + struct css_set *cg, struct cgroup *cgrp) +{ + struct cg_cgroup_link *link; + + BUG_ON(list_empty(tmp_cg_links)); + link = list_first_entry(tmp_cg_links, struct cg_cgroup_link, + cgrp_link_list); + link->cg = cg; + list_move(&link->cgrp_link_list, &cgrp->css_sets); + list_add(&link->cg_link_list, &cg->cg_links); +} + /* * find_css_set() takes an existing cgroup group and a * cgroup object, and returns a css_set object that's @@ -399,7 +418,6 @@ static struct css_set *find_css_set( int i; struct list_head tmp_cg_links; - struct cg_cgroup_link *link; struct hlist_head *hhead; @@ -444,26 +462,11 @@ static struct css_set *find_css_set( * only do it for the first subsystem in each * hierarchy */ - if (ss->root->subsys_list.next == &ss->sibling) { - BUG_ON(list_empty(&tmp_cg_links)); - link = list_entry(tmp_cg_links.next, - struct cg_cgroup_link, - cgrp_link_list); - list_del(&link->cgrp_link_list); - list_add(&link->cgrp_link_list, &cgrp->css_sets); - link->cg = res; - list_add(&link->cg_link_list, &res->cg_links); - } - } - if (list_empty(&rootnode.subsys_list)) { - link = list_entry(tmp_cg_links.next, - struct cg_cgroup_link, - cgrp_link_list); - list_del(&link->cgrp_link_list); - list_add(&link->cgrp_link_list, &dummytop->css_sets); - link->cg = res; - list_add(&link->cg_link_list, &res->cg_links); + if (ss->root->subsys_list.next == &ss->sibling) + link_css_set(&tmp_cg_links, res, cgrp); } + if (list_empty(&rootnode.subsys_list)) + link_css_set(&tmp_cg_links, res, dummytop); BUG_ON(!list_empty(&tmp_cg_links)); @@ -586,11 +589,18 @@ static void cgroup_call_pre_destroy(struct cgroup *cgrp) { struct cgroup_subsys *ss; for_each_subsys(cgrp->root, ss) - if (ss->pre_destroy && cgrp->subsys[ss->subsys_id]) + if (ss->pre_destroy) ss->pre_destroy(ss, cgrp); return; } +static void free_cgroup_rcu(struct rcu_head *obj) +{ + struct cgroup *cgrp = container_of(obj, struct cgroup, rcu_head); + + kfree(cgrp); +} + static void cgroup_diput(struct dentry *dentry, struct inode *inode) { /* is dentry a directory ? if so, kfree() associated cgroup */ @@ -610,19 +620,19 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode) /* * Release the subsystem state objects. */ - for_each_subsys(cgrp->root, ss) { - if (cgrp->subsys[ss->subsys_id]) - ss->destroy(ss, cgrp); - } + for_each_subsys(cgrp->root, ss) + ss->destroy(ss, cgrp); cgrp->root->number_of_cgroups--; mutex_unlock(&cgroup_mutex); - /* Drop the active superblock reference that we took when we - * created the cgroup */ + /* + * Drop the active superblock reference that we took when we + * created the cgroup + */ deactivate_super(cgrp->root->sb); - kfree(cgrp); + call_rcu(&cgrp->rcu_head, free_cgroup_rcu); } iput(inode); } @@ -712,23 +722,26 @@ static int rebind_subsystems(struct cgroupfs_root *root, BUG_ON(cgrp->subsys[i]); BUG_ON(!dummytop->subsys[i]); BUG_ON(dummytop->subsys[i]->cgroup != dummytop); + mutex_lock(&ss->hierarchy_mutex); cgrp->subsys[i] = dummytop->subsys[i]; cgrp->subsys[i]->cgroup = cgrp; - list_add(&ss->sibling, &root->subsys_list); - rcu_assign_pointer(ss->root, root); + list_move(&ss->sibling, &root->subsys_list); + ss->root = root; if (ss->bind) ss->bind(ss, cgrp); - + mutex_unlock(&ss->hierarchy_mutex); } else if (bit & removed_bits) { /* We're removing this subsystem */ BUG_ON(cgrp->subsys[i] != dummytop->subsys[i]); BUG_ON(cgrp->subsys[i]->cgroup != cgrp); + mutex_lock(&ss->hierarchy_mutex); if (ss->bind) ss->bind(ss, dummytop); dummytop->subsys[i]->cgroup = dummytop; cgrp->subsys[i] = NULL; - rcu_assign_pointer(subsys[i]->root, &rootnode); - list_del(&ss->sibling); + subsys[i]->root = &rootnode; + list_move(&ss->sibling, &rootnode.subsys_list); + mutex_unlock(&ss->hierarchy_mutex); } else if (bit & final_bits) { /* Subsystem state should already exist */ BUG_ON(!cgrp->subsys[i]); @@ -990,7 +1003,7 @@ static int cgroup_get_sb(struct file_system_type *fs_type, root = NULL; } else { /* New superblock */ - struct cgroup *cgrp = &root->top_cgroup; + struct cgroup *root_cgrp = &root->top_cgroup; struct inode *inode; int i; @@ -1031,7 +1044,7 @@ static int cgroup_get_sb(struct file_system_type *fs_type, list_add(&root->root_list, &roots); root_count++; - sb->s_root->d_fsdata = &root->top_cgroup; + sb->s_root->d_fsdata = root_cgrp; root->top_cgroup.dentry = sb->s_root; /* Link the top cgroup in this hierarchy into all @@ -1042,29 +1055,18 @@ static int cgroup_get_sb(struct file_system_type *fs_type, struct hlist_node *node; struct css_set *cg; - hlist_for_each_entry(cg, node, hhead, hlist) { - struct cg_cgroup_link *link; - - BUG_ON(list_empty(&tmp_cg_links)); - link = list_entry(tmp_cg_links.next, - struct cg_cgroup_link, - cgrp_link_list); - list_del(&link->cgrp_link_list); - link->cg = cg; - list_add(&link->cgrp_link_list, - &root->top_cgroup.css_sets); - list_add(&link->cg_link_list, &cg->cg_links); - } + hlist_for_each_entry(cg, node, hhead, hlist) + link_css_set(&tmp_cg_links, cg, root_cgrp); } write_unlock(&css_set_lock); free_cg_links(&tmp_cg_links); - BUG_ON(!list_empty(&cgrp->sibling)); - BUG_ON(!list_empty(&cgrp->children)); + BUG_ON(!list_empty(&root_cgrp->sibling)); + BUG_ON(!list_empty(&root_cgrp->children)); BUG_ON(root->number_of_cgroups != 1); - cgroup_populate_dir(cgrp); + cgroup_populate_dir(root_cgrp); mutex_unlock(&inode->i_mutex); mutex_unlock(&cgroup_mutex); } @@ -1113,10 +1115,9 @@ static void cgroup_kill_sb(struct super_block *sb) { } write_unlock(&css_set_lock); - if (!list_empty(&root->root_list)) { - list_del(&root->root_list); - root_count--; - } + list_del(&root->root_list); + root_count--; + mutex_unlock(&cgroup_mutex); kfree(root); @@ -1145,14 +1146,16 @@ static inline struct cftype *__d_cft(struct dentry *dentry) * @buf: the buffer to write the path into * @buflen: the length of the buffer * - * Called with cgroup_mutex held. Writes path of cgroup into buf. - * Returns 0 on success, -errno on error. + * Called with cgroup_mutex held or else with an RCU-protected cgroup + * reference. Writes path of cgroup into buf. Returns 0 on success, + * -errno on error. */ int cgroup_path(const struct cgroup *cgrp, char *buf, int buflen) { char *start; + struct dentry *dentry = rcu_dereference(cgrp->dentry); - if (cgrp == dummytop) { + if (!dentry || cgrp == dummytop) { /* * Inactive subsystems have no dentry for their root * cgroup @@ -1165,13 +1168,14 @@ int cgroup_path(const struct cgroup *cgrp, char *buf, int buflen) *--start = '\0'; for (;;) { - int len = cgrp->dentry->d_name.len; + int len = dentry->d_name.len; if ((start -= len) < buf) return -ENAMETOOLONG; memcpy(start, cgrp->dentry->d_name.name, len); cgrp = cgrp->parent; if (!cgrp) break; + dentry = rcu_dereference(cgrp->dentry); if (!cgrp->parent) continue; if (--start < buf) @@ -1216,7 +1220,7 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk) int retval = 0; struct cgroup_subsys *ss; struct cgroup *oldcgrp; - struct css_set *cg = tsk->cgroups; + struct css_set *cg; struct css_set *newcg; struct cgroupfs_root *root = cgrp->root; int subsys_id; @@ -1236,11 +1240,16 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk) } } + task_lock(tsk); + cg = tsk->cgroups; + get_css_set(cg); + task_unlock(tsk); /* * Locate or allocate a new css_set for this task, * based on its final set of cgroups */ newcg = find_css_set(cg, cgrp); + put_css_set(cg); if (!newcg) return -ENOMEM; @@ -1445,7 +1454,7 @@ static ssize_t cgroup_file_write(struct file *file, const char __user *buf, struct cftype *cft = __d_cft(file->f_dentry); struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent); - if (!cft || cgroup_is_removed(cgrp)) + if (cgroup_is_removed(cgrp)) return -ENODEV; if (cft->write) return cft->write(cgrp, cft, file, buf, nbytes, ppos); @@ -1490,7 +1499,7 @@ static ssize_t cgroup_file_read(struct file *file, char __user *buf, struct cftype *cft = __d_cft(file->f_dentry); struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent); - if (!cft || cgroup_is_removed(cgrp)) + if (cgroup_is_removed(cgrp)) return -ENODEV; if (cft->read) @@ -1554,10 +1563,8 @@ static int cgroup_file_open(struct inode *inode, struct file *file) err = generic_file_open(inode, file); if (err) return err; - cft = __d_cft(file->f_dentry); - if (!cft) - return -ENODEV; + if (cft->read_map || cft->read_seq_string) { struct cgroup_seqfile_state *state = kzalloc(sizeof(*state), GFP_USER); @@ -1671,7 +1678,7 @@ static int cgroup_create_dir(struct cgroup *cgrp, struct dentry *dentry, if (!error) { dentry->d_fsdata = cgrp; inc_nlink(parent->d_inode); - cgrp->dentry = dentry; + rcu_assign_pointer(cgrp->dentry, dentry); dget(dentry); } dput(dentry); @@ -1812,6 +1819,7 @@ struct task_struct *cgroup_iter_next(struct cgroup *cgrp, { struct task_struct *res; struct list_head *l = it->task; + struct cg_cgroup_link *link; /* If the iterator cg is NULL, we have no tasks */ if (!it->cg_link) @@ -1819,7 +1827,8 @@ struct task_struct *cgroup_iter_next(struct cgroup *cgrp, res = list_entry(l, struct task_struct, cg_list); /* Advance iterator to find next entry */ l = l->next; - if (l == &res->cgroups->tasks) { + link = list_entry(it->cg_link, struct cg_cgroup_link, cgrp_link_list); + if (l == &link->cg->tasks) { /* We reached the end of this task list - move on to * the next cg_cgroup_link */ cgroup_advance_iter(cgrp, it); @@ -2013,14 +2022,16 @@ int cgroup_scan_tasks(struct cgroup_scanner *scan) */ static int pid_array_load(pid_t *pidarray, int npids, struct cgroup *cgrp) { - int n = 0; + int n = 0, pid; struct cgroup_iter it; struct task_struct *tsk; cgroup_iter_start(cgrp, &it); while ((tsk = cgroup_iter_next(cgrp, &it))) { if (unlikely(n == npids)) break; - pidarray[n++] = task_pid_vnr(tsk); + pid = task_pid_vnr(tsk); + if (pid > 0) + pidarray[n++] = pid; } cgroup_iter_end(cgrp, &it); return n; @@ -2052,7 +2063,6 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry) ret = 0; cgrp = dentry->d_fsdata; - rcu_read_lock(); cgroup_iter_start(cgrp, &it); while ((tsk = cgroup_iter_next(cgrp, &it))) { @@ -2077,7 +2087,6 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry) } cgroup_iter_end(cgrp, &it); - rcu_read_unlock(); err: return ret; } @@ -2324,7 +2333,7 @@ static void init_cgroup_css(struct cgroup_subsys_state *css, struct cgroup *cgrp) { css->cgroup = cgrp; - atomic_set(&css->refcnt, 0); + atomic_set(&css->refcnt, 1); css->flags = 0; if (cgrp == dummytop) set_bit(CSS_ROOT, &css->flags); @@ -2332,6 +2341,29 @@ static void init_cgroup_css(struct cgroup_subsys_state *css, cgrp->subsys[ss->subsys_id] = css; } +static void cgroup_lock_hierarchy(struct cgroupfs_root *root) +{ + /* We need to take each hierarchy_mutex in a consistent order */ + int i; + + for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) { + struct cgroup_subsys *ss = subsys[i]; + if (ss->root == root) + mutex_lock_nested(&ss->hierarchy_mutex, i); + } +} + +static void cgroup_unlock_hierarchy(struct cgroupfs_root *root) +{ + int i; + + for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) { + struct cgroup_subsys *ss = subsys[i]; + if (ss->root == root) + mutex_unlock(&ss->hierarchy_mutex); + } +} + /* * cgroup_create - create a cgroup * @parent: cgroup that will be parent of the new cgroup @@ -2380,7 +2412,9 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry, init_cgroup_css(css, ss, cgrp); } + cgroup_lock_hierarchy(root); list_add(&cgrp->sibling, &cgrp->parent->children); + cgroup_unlock_hierarchy(root); root->number_of_cgroups++; err = cgroup_create_dir(cgrp, dentry, mode); @@ -2431,7 +2465,7 @@ static int cgroup_has_css_refs(struct cgroup *cgrp) { /* Check the reference count on each subsystem. Since we * already established that there are no tasks in the - * cgroup, if the css refcount is also 0, then there should + * cgroup, if the css refcount is also 1, then there should * be no outstanding references, so the subsystem is safe to * destroy. We scan across all subsystems rather than using * the per-hierarchy linked list of mounted subsystems since @@ -2452,19 +2486,67 @@ static int cgroup_has_css_refs(struct cgroup *cgrp) * matter, since it can only happen if the cgroup * has been deleted and hence no longer needs the * release agent to be called anyway. */ - if (css && atomic_read(&css->refcnt)) + if (css && (atomic_read(&css->refcnt) > 1)) return 1; } return 0; } +/* + * Atomically mark all (or else none) of the cgroup's CSS objects as + * CSS_REMOVED. Return true on success, or false if the cgroup has + * busy subsystems. Call with cgroup_mutex held + */ + +static int cgroup_clear_css_refs(struct cgroup *cgrp) +{ + struct cgroup_subsys *ss; + unsigned long flags; + bool failed = false; + local_irq_save(flags); + for_each_subsys(cgrp->root, ss) { + struct cgroup_subsys_state *css = cgrp->subsys[ss->subsys_id]; + int refcnt; + do { + /* We can only remove a CSS with a refcnt==1 */ + refcnt = atomic_read(&css->refcnt); + if (refcnt > 1) { + failed = true; + goto done; + } + BUG_ON(!refcnt); + /* + * Drop the refcnt to 0 while we check other + * subsystems. This will cause any racing + * css_tryget() to spin until we set the + * CSS_REMOVED bits or abort + */ + } while (atomic_cmpxchg(&css->refcnt, refcnt, 0) != refcnt); + } + done: + for_each_subsys(cgrp->root, ss) { + struct cgroup_subsys_state *css = cgrp->subsys[ss->subsys_id]; + if (failed) { + /* + * Restore old refcnt if we previously managed + * to clear it from 1 to 0 + */ + if (!atomic_read(&css->refcnt)) + atomic_set(&css->refcnt, 1); + } else { + /* Commit the fact that the CSS is removed */ + set_bit(CSS_REMOVED, &css->flags); + } + } + local_irq_restore(flags); + return !failed; +} + static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry) { struct cgroup *cgrp = dentry->d_fsdata; struct dentry *d; struct cgroup *parent; - struct super_block *sb; - struct cgroupfs_root *root; /* the vfs holds both inode->i_mutex already */ @@ -2487,12 +2569,10 @@ static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry) mutex_lock(&cgroup_mutex); parent = cgrp->parent; - root = cgrp->root; - sb = root->sb; if (atomic_read(&cgrp->count) || !list_empty(&cgrp->children) - || cgroup_has_css_refs(cgrp)) { + || !cgroup_clear_css_refs(cgrp)) { mutex_unlock(&cgroup_mutex); return -EBUSY; } @@ -2502,8 +2582,12 @@ static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry) if (!list_empty(&cgrp->release_list)) list_del(&cgrp->release_list); spin_unlock(&release_list_lock); - /* delete my sibling from parent->children */ + + cgroup_lock_hierarchy(cgrp->root); + /* delete this cgroup from parent->children */ list_del(&cgrp->sibling); + cgroup_unlock_hierarchy(cgrp->root); + spin_lock(&cgrp->dentry->d_lock); d = dget(cgrp->dentry); spin_unlock(&d->d_lock); @@ -2525,6 +2609,7 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss) printk(KERN_INFO "Initializing cgroup subsys %s\n", ss->name); /* Create the top cgroup state for this subsystem */ + list_add(&ss->sibling, &rootnode.subsys_list); ss->root = &rootnode; css = ss->create(ss, dummytop); /* We don't handle early failures gracefully */ @@ -2544,6 +2629,7 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss) * need to invoke fork callbacks here. */ BUG_ON(!list_empty(&init_task.tasks)); + mutex_init(&ss->hierarchy_mutex); ss->active = 1; } @@ -2562,7 +2648,6 @@ int __init cgroup_init_early(void) INIT_HLIST_NODE(&init_css_set.hlist); css_set_count = 1; init_cgroup_root(&rootnode); - list_add(&rootnode.root_list, &roots); root_count = 1; init_task.cgroups = &init_css_set; @@ -2669,15 +2754,12 @@ static int proc_cgroup_show(struct seq_file *m, void *v) mutex_lock(&cgroup_mutex); - for_each_root(root) { + for_each_active_root(root) { struct cgroup_subsys *ss; struct cgroup *cgrp; int subsys_id; int count = 0; - /* Skip this hierarchy if it has no active subsystems */ - if (!root->actual_subsys_bits) - continue; seq_printf(m, "%lu:", root->subsys_bits); for_each_subsys(root, ss) seq_printf(m, "%s%s", count++ ? "," : "", ss->name); @@ -2800,8 +2882,10 @@ 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)) list_add(&child->cg_list, &child->cgroups->tasks); + task_unlock(child); write_unlock(&css_set_lock); } } @@ -2907,6 +2991,7 @@ int cgroup_clone(struct task_struct *tsk, struct cgroup_subsys *subsys, mutex_unlock(&cgroup_mutex); return 0; } + task_lock(tsk); cg = tsk->cgroups; parent = task_cgroup(tsk, subsys->subsys_id); @@ -2919,6 +3004,7 @@ int cgroup_clone(struct task_struct *tsk, struct cgroup_subsys *subsys, /* Keep the cgroup alive */ get_css_set(cg); + task_unlock(tsk); mutex_unlock(&cgroup_mutex); /* Now do the VFS work to create a cgroup */ @@ -2937,7 +3023,7 @@ int cgroup_clone(struct task_struct *tsk, struct cgroup_subsys *subsys, } /* Create the cgroup directory, which also creates the cgroup */ - ret = vfs_mkdir(inode, dentry, S_IFDIR | 0755); + ret = vfs_mkdir(inode, dentry, 0755); child = __d_cgrp(dentry); dput(dentry); if (ret) { @@ -2947,13 +3033,6 @@ int cgroup_clone(struct task_struct *tsk, struct cgroup_subsys *subsys, goto out_release; } - if (!child) { - printk(KERN_INFO - "Couldn't find new cgroup %s\n", nodename); - ret = -ENOMEM; - goto out_release; - } - /* The cgroup now exists. Retake cgroup_mutex and check * that we're still in the same state that we thought we * were. */ @@ -3049,7 +3128,8 @@ void __css_put(struct cgroup_subsys_state *css) { struct cgroup *cgrp = css->cgroup; rcu_read_lock(); - if (atomic_dec_and_test(&css->refcnt) && notify_on_release(cgrp)) { + if ((atomic_dec_return(&css->refcnt) == 1) && + notify_on_release(cgrp)) { set_bit(CGRP_RELEASABLE, &cgrp->flags); check_for_release(cgrp); } diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 345ace5..647c77a 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -84,7 +84,7 @@ struct cpuset { struct cgroup_subsys_state css; unsigned long flags; /* "unsigned long" so bitops work */ - cpumask_t cpus_allowed; /* CPUs allowed to tasks in cpuset */ + cpumask_var_t cpus_allowed; /* CPUs allowed to tasks in cpuset */ nodemask_t mems_allowed; /* Memory Nodes allowed to tasks */ struct cpuset *parent; /* my parent */ @@ -195,8 +195,6 @@ static int cpuset_mems_generation; static struct cpuset top_cpuset = { .flags = ((1 << CS_CPU_EXCLUSIVE) | (1 << CS_MEM_EXCLUSIVE)), - .cpus_allowed = CPU_MASK_ALL, - .mems_allowed = NODE_MASK_ALL, }; /* @@ -278,7 +276,7 @@ static struct file_system_type cpuset_fs_type = { }; /* - * Return in *pmask the portion of a cpusets's cpus_allowed that + * Return in pmask the portion of a cpusets's cpus_allowed that * are online. If none are online, walk up the cpuset hierarchy * until we find one that does have some online cpus. If we get * all the way to the top and still haven't found any online cpus, @@ -291,15 +289,16 @@ static struct file_system_type cpuset_fs_type = { * Call with callback_mutex held. */ -static void guarantee_online_cpus(const struct cpuset *cs, cpumask_t *pmask) +static void guarantee_online_cpus(const struct cpuset *cs, + struct cpumask *pmask) { - while (cs && !cpus_intersects(cs->cpus_allowed, cpu_online_map)) + while (cs && !cpumask_intersects(cs->cpus_allowed, cpu_online_mask)) cs = cs->parent; if (cs) - cpus_and(*pmask, cs->cpus_allowed, cpu_online_map); + cpumask_and(pmask, cs->cpus_allowed, cpu_online_mask); else - *pmask = cpu_online_map; - BUG_ON(!cpus_intersects(*pmask, cpu_online_map)); + cpumask_copy(pmask, cpu_online_mask); + BUG_ON(!cpumask_intersects(pmask, cpu_online_mask)); } /* @@ -375,14 +374,9 @@ void cpuset_update_task_memory_state(void) struct task_struct *tsk = current; struct cpuset *cs; - if (task_cs(tsk) == &top_cpuset) { - /* Don't need rcu for top_cpuset. It's never freed. */ - my_cpusets_mem_gen = top_cpuset.mems_generation; - } else { - rcu_read_lock(); - my_cpusets_mem_gen = task_cs(tsk)->mems_generation; - rcu_read_unlock(); - } + rcu_read_lock(); + my_cpusets_mem_gen = task_cs(tsk)->mems_generation; + rcu_read_unlock(); if (my_cpusets_mem_gen != tsk->cpuset_mems_generation) { mutex_lock(&callback_mutex); @@ -414,12 +408,43 @@ void cpuset_update_task_memory_state(void) static int is_cpuset_subset(const struct cpuset *p, const struct cpuset *q) { - return cpus_subset(p->cpus_allowed, q->cpus_allowed) && + return cpumask_subset(p->cpus_allowed, q->cpus_allowed) && nodes_subset(p->mems_allowed, q->mems_allowed) && is_cpu_exclusive(p) <= is_cpu_exclusive(q) && is_mem_exclusive(p) <= is_mem_exclusive(q); } +/** + * alloc_trial_cpuset - allocate a trial cpuset + * @cs: the cpuset that the trial cpuset duplicates + */ +static struct cpuset *alloc_trial_cpuset(const struct cpuset *cs) +{ + struct cpuset *trial; + + trial = kmemdup(cs, sizeof(*cs), GFP_KERNEL); + if (!trial) + return NULL; + + if (!alloc_cpumask_var(&trial->cpus_allowed, GFP_KERNEL)) { + kfree(trial); + return NULL; + } + cpumask_copy(trial->cpus_allowed, cs->cpus_allowed); + + return trial; +} + +/** + * free_trial_cpuset - free the trial cpuset + * @trial: the trial cpuset to be freed + */ +static void free_trial_cpuset(struct cpuset *trial) +{ + free_cpumask_var(trial->cpus_allowed); + kfree(trial); +} + /* * validate_change() - Used to validate that any proposed cpuset change * follows the structural rules for cpusets. @@ -469,7 +494,7 @@ static int validate_change(const struct cpuset *cur, const struct cpuset *trial) c = cgroup_cs(cont); if ((is_cpu_exclusive(trial) || is_cpu_exclusive(c)) && c != cur && - cpus_intersects(trial->cpus_allowed, c->cpus_allowed)) + cpumask_intersects(trial->cpus_allowed, c->cpus_allowed)) return -EINVAL; if ((is_mem_exclusive(trial) || is_mem_exclusive(c)) && c != cur && @@ -479,7 +504,7 @@ static int validate_change(const struct cpuset *cur, const struct cpuset *trial) /* Cpusets with tasks can't have empty cpus_allowed or mems_allowed */ if (cgroup_task_count(cur->css.cgroup)) { - if (cpus_empty(trial->cpus_allowed) || + if (cpumask_empty(trial->cpus_allowed) || nodes_empty(trial->mems_allowed)) { return -ENOSPC; } @@ -494,7 +519,7 @@ static int validate_change(const struct cpuset *cur, const struct cpuset *trial) */ static int cpusets_overlap(struct cpuset *a, struct cpuset *b) { - return cpus_intersects(a->cpus_allowed, b->cpus_allowed); + return cpumask_intersects(a->cpus_allowed, b->cpus_allowed); } static void @@ -519,7 +544,7 @@ update_domain_attr_tree(struct sched_domain_attr *dattr, struct cpuset *c) cp = list_first_entry(&q, struct cpuset, stack_list); list_del(q.next); - if (cpus_empty(cp->cpus_allowed)) + if (cpumask_empty(cp->cpus_allowed)) continue; if (is_sched_load_balance(cp)) @@ -586,7 +611,8 @@ update_domain_attr_tree(struct sched_domain_attr *dattr, struct cpuset *c) * element of the partition (one sched domain) to be passed to * partition_sched_domains(). */ -static int generate_sched_domains(cpumask_t **domains, +/* FIXME: see the FIXME in partition_sched_domains() */ +static int generate_sched_domains(struct cpumask **domains, struct sched_domain_attr **attributes) { LIST_HEAD(q); /* queue of cpusets to be scanned */ @@ -594,10 +620,10 @@ static int generate_sched_domains(cpumask_t **domains, struct cpuset **csa; /* array of all cpuset ptrs */ int csn; /* how many cpuset ptrs in csa so far */ int i, j, k; /* indices for partition finding loops */ - cpumask_t *doms; /* resulting partition; i.e. sched domains */ + struct cpumask *doms; /* resulting partition; i.e. sched domains */ struct sched_domain_attr *dattr; /* attributes for custom domains */ int ndoms = 0; /* number of sched domains in result */ - int nslot; /* next empty doms[] cpumask_t slot */ + int nslot; /* next empty doms[] struct cpumask slot */ doms = NULL; dattr = NULL; @@ -605,7 +631,7 @@ static int generate_sched_domains(cpumask_t **domains, /* Special case for the 99% of systems with one, full, sched domain */ if (is_sched_load_balance(&top_cpuset)) { - doms = kmalloc(sizeof(cpumask_t), GFP_KERNEL); + doms = kmalloc(cpumask_size(), GFP_KERNEL); if (!doms) goto done; @@ -614,7 +640,7 @@ static int generate_sched_domains(cpumask_t **domains, *dattr = SD_ATTR_INIT; update_domain_attr_tree(dattr, &top_cpuset); } - *doms = top_cpuset.cpus_allowed; + cpumask_copy(doms, top_cpuset.cpus_allowed); ndoms = 1; goto done; @@ -633,7 +659,7 @@ static int generate_sched_domains(cpumask_t **domains, cp = list_first_entry(&q, struct cpuset, stack_list); list_del(q.next); - if (cpus_empty(cp->cpus_allowed)) + if (cpumask_empty(cp->cpus_allowed)) continue; /* @@ -684,7 +710,7 @@ restart: * Now we know how many domains to create. * Convert <csn, csa> to <ndoms, doms> and populate cpu masks. */ - doms = kmalloc(ndoms * sizeof(cpumask_t), GFP_KERNEL); + doms = kmalloc(ndoms * cpumask_size(), GFP_KERNEL); if (!doms) goto done; @@ -696,7 +722,7 @@ restart: for (nslot = 0, i = 0; i < csn; i++) { struct cpuset *a = csa[i]; - cpumask_t *dp; + struct cpumask *dp; int apn = a->pn; if (apn < 0) { @@ -719,14 +745,14 @@ restart: continue; } - cpus_clear(*dp); + cpumask_clear(dp); if (dattr) *(dattr + nslot) = SD_ATTR_INIT; for (j = i; j < csn; j++) { struct cpuset *b = csa[j]; if (apn == b->pn) { - cpus_or(*dp, *dp, b->cpus_allowed); + cpumask_or(dp, dp, b->cpus_allowed); if (dattr) update_domain_attr_tree(dattr + nslot, b); @@ -766,7 +792,7 @@ done: static void do_rebuild_sched_domains(struct work_struct *unused) { struct sched_domain_attr *attr; - cpumask_t *doms; + struct cpumask *doms; int ndoms; get_online_cpus(); @@ -835,7 +861,7 @@ void rebuild_sched_domains(void) static int cpuset_test_cpumask(struct task_struct *tsk, struct cgroup_scanner *scan) { - return !cpus_equal(tsk->cpus_allowed, + return !cpumask_equal(&tsk->cpus_allowed, (cgroup_cs(scan->cg))->cpus_allowed); } @@ -853,7 +879,7 @@ static int cpuset_test_cpumask(struct task_struct *tsk, static void cpuset_change_cpumask(struct task_struct *tsk, struct cgroup_scanner *scan) { - set_cpus_allowed_ptr(tsk, &((cgroup_cs(scan->cg))->cpus_allowed)); + set_cpus_allowed_ptr(tsk, ((cgroup_cs(scan->cg))->cpus_allowed)); } /** @@ -885,10 +911,10 @@ static void update_tasks_cpumask(struct cpuset *cs, struct ptr_heap *heap) * @cs: the cpuset to consider * @buf: buffer of cpu numbers written to this cpuset */ -static int update_cpumask(struct cpuset *cs, const char *buf) +static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, + const char *buf) { struct ptr_heap heap; - struct cpuset trialcs; int retval; int is_load_balanced; @@ -896,8 +922,6 @@ static int update_cpumask(struct cpuset *cs, const char *buf) if (cs == &top_cpuset) return -EACCES; - trialcs = *cs; - /* * An empty cpus_allowed is ok only if the cpuset has no tasks. * Since cpulist_parse() fails on an empty mask, we special case @@ -905,31 +929,31 @@ static int update_cpumask(struct cpuset *cs, const char *buf) * with tasks have cpus. */ if (!*buf) { - cpus_clear(trialcs.cpus_allowed); + cpumask_clear(trialcs->cpus_allowed); } else { - retval = cpulist_parse(buf, &trialcs.cpus_allowed); + retval = cpulist_parse(buf, trialcs->cpus_allowed); if (retval < 0) return retval; - if (!cpus_subset(trialcs.cpus_allowed, cpu_online_map)) + if (!cpumask_subset(trialcs->cpus_allowed, cpu_online_mask)) return -EINVAL; } - retval = validate_change(cs, &trialcs); + retval = validate_change(cs, trialcs); if (retval < 0) return retval; /* Nothing to do if the cpus didn't change */ - if (cpus_equal(cs->cpus_allowed, trialcs.cpus_allowed)) + if (cpumask_equal(cs->cpus_allowed, trialcs->cpus_allowed)) return 0; retval = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL); if (retval) return retval; - is_load_balanced = is_sched_load_balance(&trialcs); + is_load_balanced = is_sched_load_balance(trialcs); mutex_lock(&callback_mutex); - cs->cpus_allowed = trialcs.cpus_allowed; + cpumask_copy(cs->cpus_allowed, trialcs->cpus_allowed); mutex_unlock(&callback_mutex); /* @@ -1017,7 +1041,7 @@ static int update_tasks_nodemask(struct cpuset *cs, const nodemask_t *oldmem) cpuset_being_rebound = cs; /* causes mpol_dup() rebind */ fudge = 10; /* spare mmarray[] slots */ - fudge += cpus_weight(cs->cpus_allowed); /* imagine one fork-bomb/cpu */ + fudge += cpumask_weight(cs->cpus_allowed);/* imagine 1 fork-bomb/cpu */ retval = -ENOMEM; /* @@ -1104,9 +1128,9 @@ done: * lock each such tasks mm->mmap_sem, scan its vma's and rebind * their mempolicies to the cpusets new mems_allowed. */ -static int update_nodemask(struct cpuset *cs, const char *buf) +static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs, + const char *buf) { - struct cpuset trialcs; nodemask_t oldmem; int retval; @@ -1117,8 +1141,6 @@ static int update_nodemask(struct cpuset *cs, const char *buf) if (cs == &top_cpuset) return -EACCES; - trialcs = *cs; - /* * An empty mems_allowed is ok iff there are no tasks in the cpuset. * Since nodelist_parse() fails on an empty mask, we special case @@ -1126,27 +1148,27 @@ static int update_nodemask(struct cpuset *cs, const char *buf) * with tasks have memory. */ if (!*buf) { - nodes_clear(trialcs.mems_allowed); + nodes_clear(trialcs->mems_allowed); } else { - retval = nodelist_parse(buf, trialcs.mems_allowed); + retval = nodelist_parse(buf, trialcs->mems_allowed); if (retval < 0) goto done; - if (!nodes_subset(trialcs.mems_allowed, + if (!nodes_subset(trialcs->mems_allowed, node_states[N_HIGH_MEMORY])) return -EINVAL; } oldmem = cs->mems_allowed; - if (nodes_equal(oldmem, trialcs.mems_allowed)) { + if (nodes_equal(oldmem, trialcs->mems_allowed)) { retval = 0; /* Too easy - nothing to do */ goto done; } - retval = validate_change(cs, &trialcs); + retval = validate_change(cs, trialcs); if (retval < 0) goto done; mutex_lock(&callback_mutex); - cs->mems_allowed = trialcs.mems_allowed; + cs->mems_allowed = trialcs->mems_allowed; cs->mems_generation = cpuset_mems_generation++; mutex_unlock(&callback_mutex); @@ -1167,7 +1189,8 @@ static int update_relax_domain_level(struct cpuset *cs, s64 val) if (val != cs->relax_domain_level) { cs->relax_domain_level = val; - if (!cpus_empty(cs->cpus_allowed) && is_sched_load_balance(cs)) + if (!cpumask_empty(cs->cpus_allowed) && + is_sched_load_balance(cs)) async_rebuild_sched_domains(); } @@ -1186,31 +1209,36 @@ static int update_relax_domain_level(struct cpuset *cs, s64 val) static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs, int turning_on) { - struct cpuset trialcs; + struct cpuset *trialcs; int err; int balance_flag_changed; - trialcs = *cs; + trialcs = alloc_trial_cpuset(cs); + if (!trialcs) + return -ENOMEM; + if (turning_on) - set_bit(bit, &trialcs.flags); + set_bit(bit, &trialcs->flags); else - clear_bit(bit, &trialcs.flags); + clear_bit(bit, &trialcs->flags); - err = validate_change(cs, &trialcs); + err = validate_change(cs, trialcs); if (err < 0) - return err; + goto out; balance_flag_changed = (is_sched_load_balance(cs) != - is_sched_load_balance(&trialcs)); + is_sched_load_balance(trialcs)); mutex_lock(&callback_mutex); - cs->flags = trialcs.flags; + cs->flags = trialcs->flags; mutex_unlock(&callback_mutex); - if (!cpus_empty(trialcs.cpus_allowed) && balance_flag_changed) + if (!cpumask_empty(trialcs->cpus_allowed) && balance_flag_changed) async_rebuild_sched_domains(); - return 0; +out: + free_trial_cpuset(trialcs); + return err; } /* @@ -1311,42 +1339,47 @@ static int fmeter_getrate(struct fmeter *fmp) return val; } +/* Protected by cgroup_lock */ +static cpumask_var_t cpus_attach; + /* 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); + int ret = 0; - if (cpus_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)) + if (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)) return -ENOSPC; - if (tsk->flags & PF_THREAD_BOUND) { - cpumask_t mask; + if (tsk->flags & PF_THREAD_BOUND) { mutex_lock(&callback_mutex); - mask = cs->cpus_allowed; + if (!cpumask_equal(&tsk->cpus_allowed, cs->cpus_allowed)) + ret = -EINVAL; mutex_unlock(&callback_mutex); - if (!cpus_equal(tsk->cpus_allowed, mask)) - return -EINVAL; } - return security_task_setscheduler(tsk, 0, NULL); + return ret < 0 ? ret : security_task_setscheduler(tsk, 0, NULL); } static void cpuset_attach(struct cgroup_subsys *ss, struct cgroup *cont, struct cgroup *oldcont, struct task_struct *tsk) { - cpumask_t cpus; nodemask_t from, to; struct mm_struct *mm; struct cpuset *cs = cgroup_cs(cont); struct cpuset *oldcs = cgroup_cs(oldcont); int err; - mutex_lock(&callback_mutex); - guarantee_online_cpus(cs, &cpus); - err = set_cpus_allowed_ptr(tsk, &cpus); - mutex_unlock(&callback_mutex); + if (cs == &top_cpuset) { + cpumask_copy(cpus_attach, cpu_possible_mask); + } else { + mutex_lock(&callback_mutex); + guarantee_online_cpus(cs, cpus_attach); + mutex_unlock(&callback_mutex); + } + err = set_cpus_allowed_ptr(tsk, cpus_attach); if (err) return; @@ -1359,7 +1392,6 @@ static void cpuset_attach(struct cgroup_subsys *ss, cpuset_migrate_mm(mm, &from, &to); mmput(mm); } - } /* The various types of files and directories in a cpuset file system */ @@ -1454,21 +1486,29 @@ static int cpuset_write_resmask(struct cgroup *cgrp, struct cftype *cft, const char *buf) { int retval = 0; + struct cpuset *cs = cgroup_cs(cgrp); + struct cpuset *trialcs; if (!cgroup_lock_live_group(cgrp)) return -ENODEV; + trialcs = alloc_trial_cpuset(cs); + if (!trialcs) + return -ENOMEM; + switch (cft->private) { case FILE_CPULIST: - retval = update_cpumask(cgroup_cs(cgrp), buf); + retval = update_cpumask(cs, trialcs, buf); break; case FILE_MEMLIST: - retval = update_nodemask(cgroup_cs(cgrp), buf); + retval = update_nodemask(cs, trialcs, buf); break; default: retval = -EINVAL; break; } + + free_trial_cpuset(trialcs); cgroup_unlock(); return retval; } @@ -1487,13 +1527,13 @@ static int cpuset_write_resmask(struct cgroup *cgrp, struct cftype *cft, static int cpuset_sprintf_cpulist(char *page, struct cpuset *cs) { - cpumask_t mask; + int ret; mutex_lock(&callback_mutex); - mask = cs->cpus_allowed; + ret = cpulist_scnprintf(page, PAGE_SIZE, cs->cpus_allowed); mutex_unlock(&callback_mutex); - return cpulist_scnprintf(page, PAGE_SIZE, &mask); + return ret; } static int cpuset_sprintf_memlist(char *page, struct cpuset *cs) @@ -1729,7 +1769,7 @@ static void cpuset_post_clone(struct cgroup_subsys *ss, parent_cs = cgroup_cs(parent); cs->mems_allowed = parent_cs->mems_allowed; - cs->cpus_allowed = parent_cs->cpus_allowed; + cpumask_copy(cs->cpus_allowed, parent_cs->cpus_allowed); return; } @@ -1755,6 +1795,10 @@ static struct cgroup_subsys_state *cpuset_create( cs = kmalloc(sizeof(*cs), GFP_KERNEL); if (!cs) return ERR_PTR(-ENOMEM); + if (!alloc_cpumask_var(&cs->cpus_allowed, GFP_KERNEL)) { + kfree(cs); + return ERR_PTR(-ENOMEM); + } cpuset_update_task_memory_state(); cs->flags = 0; @@ -1763,7 +1807,7 @@ static struct cgroup_subsys_state *cpuset_create( if (is_spread_slab(parent)) set_bit(CS_SPREAD_SLAB, &cs->flags); set_bit(CS_SCHED_LOAD_BALANCE, &cs->flags); - cpus_clear(cs->cpus_allowed); + cpumask_clear(cs->cpus_allowed); nodes_clear(cs->mems_allowed); cs->mems_generation = cpuset_mems_generation++; fmeter_init(&cs->fmeter); @@ -1790,6 +1834,7 @@ static void cpuset_destroy(struct cgroup_subsys *ss, struct cgroup *cont) update_flag(CS_SCHED_LOAD_BALANCE, cs, 0); number_of_cpusets--; + free_cpumask_var(cs->cpus_allowed); kfree(cs); } @@ -1813,6 +1858,8 @@ struct cgroup_subsys cpuset_subsys = { int __init cpuset_init_early(void) { + alloc_bootmem_cpumask_var(&top_cpuset.cpus_allowed); + top_cpuset.mems_generation = cpuset_mems_generation++; return 0; } @@ -1828,7 +1875,7 @@ int __init cpuset_init(void) { int err = 0; - cpus_setall(top_cpuset.cpus_allowed); + cpumask_setall(top_cpuset.cpus_allowed); nodes_setall(top_cpuset.mems_allowed); fmeter_init(&top_cpuset.fmeter); @@ -1840,6 +1887,9 @@ int __init cpuset_init(void) if (err < 0) return err; + if (!alloc_cpumask_var(&cpus_attach, GFP_KERNEL)) + BUG(); + number_of_cpusets = 1; return 0; } @@ -1914,7 +1964,7 @@ static void remove_tasks_in_empty_cpuset(struct cpuset *cs) * has online cpus, so can't be empty). */ parent = cs->parent; - while (cpus_empty(parent->cpus_allowed) || + while (cpumask_empty(parent->cpus_allowed) || nodes_empty(parent->mems_allowed)) parent = parent->parent; @@ -1955,7 +2005,7 @@ static void scan_for_empty_cpusets(struct cpuset *root) } /* Continue past cpusets with all cpus, mems online */ - if (cpus_subset(cp->cpus_allowed, cpu_online_map) && + if (cpumask_subset(cp->cpus_allowed, cpu_online_mask) && nodes_subset(cp->mems_allowed, node_states[N_HIGH_MEMORY])) continue; @@ -1963,13 +2013,14 @@ static void scan_for_empty_cpusets(struct cpuset *root) /* Remove offline cpus and mems from this cpuset. */ mutex_lock(&callback_mutex); - cpus_and(cp->cpus_allowed, cp->cpus_allowed, cpu_online_map); + cpumask_and(cp->cpus_allowed, cp->cpus_allowed, + cpu_online_mask); nodes_and(cp->mems_allowed, cp->mems_allowed, node_states[N_HIGH_MEMORY]); mutex_unlock(&callback_mutex); /* Move tasks from the empty cpuset to a parent */ - if (cpus_empty(cp->cpus_allowed) || + if (cpumask_empty(cp->cpus_allowed) || nodes_empty(cp->mems_allowed)) remove_tasks_in_empty_cpuset(cp); else { @@ -1995,7 +2046,7 @@ static int cpuset_track_online_cpus(struct notifier_block *unused_nb, unsigned long phase, void *unused_cpu) { struct sched_domain_attr *attr; - cpumask_t *doms; + struct cpumask *doms; int ndoms; switch (phase) { @@ -2010,7 +2061,7 @@ static int cpuset_track_online_cpus(struct notifier_block *unused_nb, } cgroup_lock(); - top_cpuset.cpus_allowed = cpu_online_map; + cpumask_copy(top_cpuset.cpus_allowed, cpu_online_mask); scan_for_empty_cpusets(&top_cpuset); ndoms = generate_sched_domains(&doms, &attr); cgroup_unlock(); @@ -2055,7 +2106,7 @@ static int cpuset_track_online_nodes(struct notifier_block *self, void __init cpuset_init_smp(void) { - top_cpuset.cpus_allowed = cpu_online_map; + cpumask_copy(top_cpuset.cpus_allowed, cpu_online_mask); top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY]; hotcpu_notifier(cpuset_track_online_cpus, 0); @@ -2065,15 +2116,15 @@ void __init cpuset_init_smp(void) /** * cpuset_cpus_allowed - return cpus_allowed mask from a tasks cpuset. * @tsk: pointer to task_struct from which to obtain cpuset->cpus_allowed. - * @pmask: pointer to cpumask_t variable to receive cpus_allowed set. + * @pmask: pointer to struct cpumask variable to receive cpus_allowed set. * - * Description: Returns the cpumask_t cpus_allowed of the cpuset + * Description: Returns the cpumask_var_t cpus_allowed of the cpuset * attached to the specified @tsk. Guaranteed to return some non-empty * subset of cpu_online_map, even if this means going outside the * tasks cpuset. **/ -void cpuset_cpus_allowed(struct task_struct *tsk, cpumask_t *pmask) +void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask) { mutex_lock(&callback_mutex); cpuset_cpus_allowed_locked(tsk, pmask); @@ -2084,7 +2135,7 @@ void cpuset_cpus_allowed(struct task_struct *tsk, cpumask_t *pmask) * cpuset_cpus_allowed_locked - return cpus_allowed mask from a tasks cpuset. * Must be called with callback_mutex held. **/ -void cpuset_cpus_allowed_locked(struct task_struct *tsk, cpumask_t *pmask) +void cpuset_cpus_allowed_locked(struct task_struct *tsk, struct cpumask *pmask) { task_lock(tsk); guarantee_online_cpus(task_cs(tsk), pmask); diff --git a/kernel/cred.c b/kernel/cred.c index ff7bc07..3a03918 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -372,7 +372,8 @@ int commit_creds(struct cred *new) old->fsuid != new->fsuid || old->fsgid != new->fsgid || !cap_issubset(new->cap_permitted, old->cap_permitted)) { - set_dumpable(task->mm, suid_dumpable); + if (task->mm) + set_dumpable(task->mm, suid_dumpable); task->pdeath_signal = 0; smp_wmb(); } @@ -506,6 +507,7 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon) else old = get_cred(&init_cred); + *new = *old; get_uid(new->user); get_group_info(new->group_info); @@ -529,6 +531,7 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon) error: put_cred(new); + put_cred(old); return NULL; } EXPORT_SYMBOL(prepare_kernel_cred); diff --git a/kernel/fork.c b/kernel/fork.c index 7b8f2a7..1d68f12 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1126,12 +1126,12 @@ static struct task_struct *copy_process(unsigned long clone_flags, if (pid != &init_struct_pid) { retval = -ENOMEM; - pid = alloc_pid(task_active_pid_ns(p)); + pid = alloc_pid(p->nsproxy->pid_ns); if (!pid) goto bad_fork_cleanup_io; if (clone_flags & CLONE_NEWPID) { - retval = pid_ns_prepare_proc(task_active_pid_ns(p)); + retval = pid_ns_prepare_proc(p->nsproxy->pid_ns); if (retval < 0) goto bad_fork_free_pid; } @@ -1481,12 +1481,10 @@ void __init proc_caches_init(void) fs_cachep = kmem_cache_create("fs_cache", sizeof(struct fs_struct), 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); - vm_area_cachep = kmem_cache_create("vm_area_struct", - sizeof(struct vm_area_struct), 0, - SLAB_PANIC, NULL); mm_cachep = kmem_cache_create("mm_struct", sizeof(struct mm_struct), ARCH_MIN_MMSTRUCT_ALIGN, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); + mmap_init(); } /* diff --git a/kernel/irq/autoprobe.c b/kernel/irq/autoprobe.c index cc0f732..1de9700 100644 --- a/kernel/irq/autoprobe.c +++ b/kernel/irq/autoprobe.c @@ -10,6 +10,7 @@ #include <linux/module.h> #include <linux/interrupt.h> #include <linux/delay.h> +#include <linux/async.h> #include "internals.h" @@ -34,6 +35,10 @@ unsigned long probe_irq_on(void) unsigned int status; int i; + /* + * quiesce the kernel, or at least the asynchronous portion + */ + async_synchronize_full(); mutex_lock(&probing_active); /* * something may have generated an irq long ago and we want to diff --git a/kernel/module.c b/kernel/module.c index 496dcb5..c9332c9 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -50,6 +50,7 @@ #include <asm/sections.h> #include <linux/tracepoint.h> #include <linux/ftrace.h> +#include <linux/async.h> #if 0 #define DEBUGP printk @@ -816,6 +817,7 @@ sys_delete_module(const char __user *name_user, unsigned int flags) mod->exit(); blocking_notifier_call_chain(&module_notify_list, MODULE_STATE_GOING, mod); + async_synchronize_full(); mutex_lock(&module_mutex); /* Store the name of the last unloaded module for diagnostic purposes */ strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); diff --git a/kernel/ns_cgroup.c b/kernel/ns_cgroup.c index 43c2111..78bc3fd 100644 --- a/kernel/ns_cgroup.c +++ b/kernel/ns_cgroup.c @@ -13,7 +13,6 @@ struct ns_cgroup { struct cgroup_subsys_state css; - spinlock_t lock; }; struct cgroup_subsys ns_subsys; @@ -84,7 +83,6 @@ static struct cgroup_subsys_state *ns_create(struct cgroup_subsys *ss, ns_cgroup = kzalloc(sizeof(*ns_cgroup), GFP_KERNEL); if (!ns_cgroup) return ERR_PTR(-ENOMEM); - spin_lock_init(&ns_cgroup->lock); return &ns_cgroup->css; } diff --git a/kernel/pid.c b/kernel/pid.c index af9224c..1b3586f 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -474,6 +474,12 @@ pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) } EXPORT_SYMBOL(task_session_nr_ns); +struct pid_namespace *task_active_pid_ns(struct task_struct *tsk) +{ + return ns_of_pid(task_pid(tsk)); +} +EXPORT_SYMBOL_GPL(task_active_pid_ns); + /* * Used by proc to find the first pid that is greater than or equal to nr. * diff --git a/kernel/power/disk.c b/kernel/power/disk.c index f77d381..45e8541 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -258,12 +258,12 @@ int hibernation_snapshot(int platform_mode) { int error; - /* Free memory before shutting down devices. */ - error = swsusp_shrink_memory(); + error = platform_begin(platform_mode); if (error) return error; - error = platform_begin(platform_mode); + /* Free memory before shutting down devices. */ + error = swsusp_shrink_memory(); if (error) goto Close; diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 5d2ab83..f5fc2d7 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -25,6 +25,7 @@ #include <linux/syscalls.h> #include <linux/console.h> #include <linux/highmem.h> +#include <linux/list.h> #include <asm/uaccess.h> #include <asm/mmu_context.h> @@ -192,12 +193,6 @@ static void *chain_alloc(struct chain_allocator *ca, unsigned int size) return ret; } -static void chain_free(struct chain_allocator *ca, int clear_page_nosave) -{ - free_list_of_pages(ca->chain, clear_page_nosave); - memset(ca, 0, sizeof(struct chain_allocator)); -} - /** * Data types related to memory bitmaps. * @@ -233,7 +228,7 @@ static void chain_free(struct chain_allocator *ca, int clear_page_nosave) #define BM_BITS_PER_BLOCK (PAGE_SIZE << 3) struct bm_block { - struct bm_block *next; /* next element of the list */ + struct list_head hook; /* hook into a list of bitmap blocks */ unsigned long start_pfn; /* pfn represented by the first bit */ unsigned long end_pfn; /* pfn represented by the last bit plus 1 */ unsigned long *data; /* bitmap representing pages */ @@ -244,24 +239,15 @@ static inline unsigned long bm_block_bits(struct bm_block *bb) return bb->end_pfn - bb->start_pfn; } -struct zone_bitmap { - struct zone_bitmap *next; /* next element of the list */ - unsigned long start_pfn; /* minimal pfn in this zone */ - unsigned long end_pfn; /* maximal pfn in this zone plus 1 */ - struct bm_block *bm_blocks; /* list of bitmap blocks */ - struct bm_block *cur_block; /* recently used bitmap block */ -}; - /* strcut bm_position is used for browsing memory bitmaps */ struct bm_position { - struct zone_bitmap *zone_bm; struct bm_block *block; int bit; }; struct memory_bitmap { - struct zone_bitmap *zone_bm_list; /* list of zone bitmaps */ + struct list_head blocks; /* list of bitmap blocks */ struct linked_page *p_list; /* list of pages used to store zone * bitmap objects and bitmap block * objects @@ -273,11 +259,7 @@ struct memory_bitmap { static void memory_bm_position_reset(struct memory_bitmap *bm) { - struct zone_bitmap *zone_bm; - - zone_bm = bm->zone_bm_list; - bm->cur.zone_bm = zone_bm; - bm->cur.block = zone_bm->bm_blocks; + bm->cur.block = list_entry(bm->blocks.next, struct bm_block, hook); bm->cur.bit = 0; } @@ -285,151 +267,184 @@ static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free); /** * create_bm_block_list - create a list of block bitmap objects + * @nr_blocks - number of blocks to allocate + * @list - list to put the allocated blocks into + * @ca - chain allocator to be used for allocating memory */ - -static inline struct bm_block * -create_bm_block_list(unsigned int nr_blocks, struct chain_allocator *ca) +static int create_bm_block_list(unsigned long pages, + struct list_head *list, + struct chain_allocator *ca) { - struct bm_block *bblist = NULL; + unsigned int nr_blocks = DIV_ROUND_UP(pages, BM_BITS_PER_BLOCK); while (nr_blocks-- > 0) { struct bm_block *bb; bb = chain_alloc(ca, sizeof(struct bm_block)); if (!bb) - return NULL; - - bb->next = bblist; - bblist = bb; + return -ENOMEM; + list_add(&bb->hook, list); } - return bblist; + + return 0; } +struct mem_extent { + struct list_head hook; + unsigned long start; + unsigned long end; +}; + /** - * create_zone_bm_list - create a list of zone bitmap objects + * free_mem_extents - free a list of memory extents + * @list - list of extents to empty */ +static void free_mem_extents(struct list_head *list) +{ + struct mem_extent *ext, *aux; -static inline struct zone_bitmap * -create_zone_bm_list(unsigned int nr_zones, struct chain_allocator *ca) + list_for_each_entry_safe(ext, aux, list, hook) { + list_del(&ext->hook); + kfree(ext); + } +} + +/** + * create_mem_extents - create a list of memory extents representing + * contiguous ranges of PFNs + * @list - list to put the extents into + * @gfp_mask - mask to use for memory allocations + */ +static int create_mem_extents(struct list_head *list, gfp_t gfp_mask) { - struct zone_bitmap *zbmlist = NULL; + struct zone *zone; - while (nr_zones-- > 0) { - struct zone_bitmap *zbm; + INIT_LIST_HEAD(list); - zbm = chain_alloc(ca, sizeof(struct zone_bitmap)); - if (!zbm) - return NULL; + for_each_zone(zone) { + unsigned long zone_start, zone_end; + struct mem_extent *ext, *cur, *aux; + + if (!populated_zone(zone)) + continue; - zbm->next = zbmlist; - zbmlist = zbm; + zone_start = zone->zone_start_pfn; + zone_end = zone->zone_start_pfn + zone->spanned_pages; + + list_for_each_entry(ext, list, hook) + if (zone_start <= ext->end) + break; + + if (&ext->hook == list || zone_end < ext->start) { + /* New extent is necessary */ + struct mem_extent *new_ext; + + new_ext = kzalloc(sizeof(struct mem_extent), gfp_mask); + if (!new_ext) { + free_mem_extents(list); + return -ENOMEM; + } + new_ext->start = zone_start; + new_ext->end = zone_end; + list_add_tail(&new_ext->hook, &ext->hook); + continue; + } + + /* Merge this zone's range of PFNs with the existing one */ + if (zone_start < ext->start) + ext->start = zone_start; + if (zone_end > ext->end) + ext->end = zone_end; + + /* More merging may be possible */ + cur = ext; + list_for_each_entry_safe_continue(cur, aux, list, hook) { + if (zone_end < cur->start) + break; + if (zone_end < cur->end) + ext->end = cur->end; + list_del(&cur->hook); + kfree(cur); + } } - return zbmlist; + + return 0; } /** * memory_bm_create - allocate memory for a memory bitmap */ - static int memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask, int safe_needed) { struct chain_allocator ca; - struct zone *zone; - struct zone_bitmap *zone_bm; - struct bm_block *bb; - unsigned int nr; + struct list_head mem_extents; + struct mem_extent *ext; + int error; chain_init(&ca, gfp_mask, safe_needed); + INIT_LIST_HEAD(&bm->blocks); - /* Compute the number of zones */ - nr = 0; - for_each_zone(zone) - if (populated_zone(zone)) - nr++; - - /* Allocate the list of zones bitmap objects */ - zone_bm = create_zone_bm_list(nr, &ca); - bm->zone_bm_list = zone_bm; - if (!zone_bm) { - chain_free(&ca, PG_UNSAFE_CLEAR); - return -ENOMEM; - } - - /* Initialize the zone bitmap objects */ - for_each_zone(zone) { - unsigned long pfn; + error = create_mem_extents(&mem_extents, gfp_mask); + if (error) + return error; - if (!populated_zone(zone)) - continue; + list_for_each_entry(ext, &mem_extents, hook) { + struct bm_block *bb; + unsigned long pfn = ext->start; + unsigned long pages = ext->end - ext->start; - zone_bm->start_pfn = zone->zone_start_pfn; - zone_bm->end_pfn = zone->zone_start_pfn + zone->spanned_pages; - /* Allocate the list of bitmap block objects */ - nr = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK); - bb = create_bm_block_list(nr, &ca); - zone_bm->bm_blocks = bb; - zone_bm->cur_block = bb; - if (!bb) - goto Free; + bb = list_entry(bm->blocks.prev, struct bm_block, hook); - nr = zone->spanned_pages; - pfn = zone->zone_start_pfn; - /* Initialize the bitmap block objects */ - while (bb) { - unsigned long *ptr; + error = create_bm_block_list(pages, bm->blocks.prev, &ca); + if (error) + goto Error; - ptr = get_image_page(gfp_mask, safe_needed); - bb->data = ptr; - if (!ptr) - goto Free; + list_for_each_entry_continue(bb, &bm->blocks, hook) { + bb->data = get_image_page(gfp_mask, safe_needed); + if (!bb->data) { + error = -ENOMEM; + goto Error; + } bb->start_pfn = pfn; - if (nr >= BM_BITS_PER_BLOCK) { + if (pages >= BM_BITS_PER_BLOCK) { pfn += BM_BITS_PER_BLOCK; - nr -= BM_BITS_PER_BLOCK; + pages -= BM_BITS_PER_BLOCK; } else { /* This is executed only once in the loop */ - pfn += nr; + pfn += pages; } bb->end_pfn = pfn; - bb = bb->next; } - zone_bm = zone_bm->next; } + bm->p_list = ca.chain; memory_bm_position_reset(bm); - return 0; + Exit: + free_mem_extents(&mem_extents); + return error; - Free: + Error: bm->p_list = ca.chain; memory_bm_free(bm, PG_UNSAFE_CLEAR); - return -ENOMEM; + goto Exit; } /** * memory_bm_free - free memory occupied by the memory bitmap @bm */ - static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free) { - struct zone_bitmap *zone_bm; + struct bm_block *bb; - /* Free the list of bit blocks for each zone_bitmap object */ - zone_bm = bm->zone_bm_list; - while (zone_bm) { - struct bm_block *bb; + list_for_each_entry(bb, &bm->blocks, hook) + if (bb->data) + free_image_page(bb->data, clear_nosave_free); - bb = zone_bm->bm_blocks; - while (bb) { - if (bb->data) - free_image_page(bb->data, clear_nosave_free); - bb = bb->next; - } - zone_bm = zone_bm->next; - } free_list_of_pages(bm->p_list, clear_nosave_free); - bm->zone_bm_list = NULL; + + INIT_LIST_HEAD(&bm->blocks); } /** @@ -437,38 +452,33 @@ static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free) * to given pfn. The cur_zone_bm member of @bm and the cur_block member * of @bm->cur_zone_bm are updated. */ - static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn, void **addr, unsigned int *bit_nr) { - struct zone_bitmap *zone_bm; struct bm_block *bb; - /* Check if the pfn is from the current zone */ - zone_bm = bm->cur.zone_bm; - if (pfn < zone_bm->start_pfn || pfn >= zone_bm->end_pfn) { - zone_bm = bm->zone_bm_list; - /* We don't assume that the zones are sorted by pfns */ - while (pfn < zone_bm->start_pfn || pfn >= zone_bm->end_pfn) { - zone_bm = zone_bm->next; - - if (!zone_bm) - return -EFAULT; - } - bm->cur.zone_bm = zone_bm; - } - /* Check if the pfn corresponds to the current bitmap block */ - bb = zone_bm->cur_block; + /* + * Check if the pfn corresponds to the current bitmap block and find + * the block where it fits if this is not the case. + */ + bb = bm->cur.block; if (pfn < bb->start_pfn) - bb = zone_bm->bm_blocks; + list_for_each_entry_continue_reverse(bb, &bm->blocks, hook) + if (pfn >= bb->start_pfn) + break; - while (pfn >= bb->end_pfn) { - bb = bb->next; + if (pfn >= bb->end_pfn) + list_for_each_entry_continue(bb, &bm->blocks, hook) + if (pfn >= bb->start_pfn && pfn < bb->end_pfn) + break; - BUG_ON(!bb); - } - zone_bm->cur_block = bb; + if (&bb->hook == &bm->blocks) + return -EFAULT; + + /* The block has been found */ + bm->cur.block = bb; pfn -= bb->start_pfn; + bm->cur.bit = pfn + 1; *bit_nr = pfn; *addr = bb->data; return 0; @@ -519,6 +529,14 @@ static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn) return test_bit(bit, addr); } +static bool memory_bm_pfn_present(struct memory_bitmap *bm, unsigned long pfn) +{ + void *addr; + unsigned int bit; + + return !memory_bm_find_bit(bm, pfn, &addr, &bit); +} + /** * memory_bm_next_pfn - find the pfn that corresponds to the next set bit * in the bitmap @bm. If the pfn cannot be found, BM_END_OF_MAP is @@ -530,29 +548,21 @@ static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn) static unsigned long memory_bm_next_pfn(struct memory_bitmap *bm) { - struct zone_bitmap *zone_bm; struct bm_block *bb; int bit; + bb = bm->cur.block; do { - bb = bm->cur.block; - do { - bit = bm->cur.bit; - bit = find_next_bit(bb->data, bm_block_bits(bb), bit); - if (bit < bm_block_bits(bb)) - goto Return_pfn; - - bb = bb->next; - bm->cur.block = bb; - bm->cur.bit = 0; - } while (bb); - zone_bm = bm->cur.zone_bm->next; - if (zone_bm) { - bm->cur.zone_bm = zone_bm; - bm->cur.block = zone_bm->bm_blocks; - bm->cur.bit = 0; - } - } while (zone_bm); + bit = bm->cur.bit; + bit = find_next_bit(bb->data, bm_block_bits(bb), bit); + if (bit < bm_block_bits(bb)) + goto Return_pfn; + + bb = list_entry(bb->hook.next, struct bm_block, hook); + bm->cur.block = bb; + bm->cur.bit = 0; + } while (&bb->hook != &bm->blocks); + memory_bm_position_reset(bm); return BM_END_OF_MAP; @@ -808,8 +818,7 @@ static unsigned int count_free_highmem_pages(void) * We should save the page if it isn't Nosave or NosaveFree, or Reserved, * and it isn't a part of a free chunk of pages. */ - -static struct page *saveable_highmem_page(unsigned long pfn) +static struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn) { struct page *page; @@ -817,6 +826,8 @@ static struct page *saveable_highmem_page(unsigned long pfn) return NULL; page = pfn_to_page(pfn); + if (page_zone(page) != zone) + return NULL; BUG_ON(!PageHighMem(page)); @@ -846,13 +857,16 @@ unsigned int count_highmem_pages(void) mark_free_pages(zone); max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) - if (saveable_highmem_page(pfn)) + if (saveable_highmem_page(zone, pfn)) n++; } return n; } #else -static inline void *saveable_highmem_page(unsigned long pfn) { return NULL; } +static inline void *saveable_highmem_page(struct zone *z, unsigned long p) +{ + return NULL; +} #endif /* CONFIG_HIGHMEM */ /** @@ -863,8 +877,7 @@ static inline void *saveable_highmem_page(unsigned long pfn) { return NULL; } * of pages statically defined as 'unsaveable', and it isn't a part of * a free chunk of pages. */ - -static struct page *saveable_page(unsigned long pfn) +static struct page *saveable_page(struct zone *zone, unsigned long pfn) { struct page *page; @@ -872,6 +885,8 @@ static struct page *saveable_page(unsigned long pfn) return NULL; page = pfn_to_page(pfn); + if (page_zone(page) != zone) + return NULL; BUG_ON(PageHighMem(page)); @@ -903,7 +918,7 @@ unsigned int count_data_pages(void) mark_free_pages(zone); max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) - if(saveable_page(pfn)) + if (saveable_page(zone, pfn)) n++; } return n; @@ -944,7 +959,7 @@ static inline struct page * page_is_saveable(struct zone *zone, unsigned long pfn) { return is_highmem(zone) ? - saveable_highmem_page(pfn) : saveable_page(pfn); + saveable_highmem_page(zone, pfn) : saveable_page(zone, pfn); } static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) @@ -966,7 +981,7 @@ static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) * data modified by kmap_atomic() */ safe_copy_page(buffer, s_page); - dst = kmap_atomic(pfn_to_page(dst_pfn), KM_USER0); + dst = kmap_atomic(d_page, KM_USER0); memcpy(dst, buffer, PAGE_SIZE); kunmap_atomic(dst, KM_USER0); } else { @@ -975,7 +990,7 @@ static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) } } #else -#define page_is_saveable(zone, pfn) saveable_page(pfn) +#define page_is_saveable(zone, pfn) saveable_page(zone, pfn) static inline void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) { @@ -1459,9 +1474,7 @@ load_header(struct swsusp_info *info) * unpack_orig_pfns - for each element of @buf[] (1 page at a time) set * the corresponding bit in the memory bitmap @bm */ - -static inline void -unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm) +static int unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm) { int j; @@ -1469,8 +1482,13 @@ unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm) if (unlikely(buf[j] == BM_END_OF_MAP)) break; - memory_bm_set_bit(bm, buf[j]); + if (memory_bm_pfn_present(bm, buf[j])) + memory_bm_set_bit(bm, buf[j]); + else + return -EFAULT; } + + return 0; } /* List of "safe" pages that may be used to store data loaded from the suspend @@ -1608,7 +1626,7 @@ get_highmem_page_buffer(struct page *page, struct chain_allocator *ca) pbe = chain_alloc(ca, sizeof(struct highmem_pbe)); if (!pbe) { swsusp_free(); - return NULL; + return ERR_PTR(-ENOMEM); } pbe->orig_page = page; if (safe_highmem_pages > 0) { @@ -1677,7 +1695,7 @@ prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p) static inline void * get_highmem_page_buffer(struct page *page, struct chain_allocator *ca) { - return NULL; + return ERR_PTR(-EINVAL); } static inline void copy_last_highmem_page(void) {} @@ -1788,8 +1806,13 @@ prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca) { struct pbe *pbe; - struct page *page = pfn_to_page(memory_bm_next_pfn(bm)); + struct page *page; + unsigned long pfn = memory_bm_next_pfn(bm); + if (pfn == BM_END_OF_MAP) + return ERR_PTR(-EFAULT); + + page = pfn_to_page(pfn); if (PageHighMem(page)) return get_highmem_page_buffer(page, ca); @@ -1805,7 +1828,7 @@ static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca) pbe = chain_alloc(ca, sizeof(struct pbe)); if (!pbe) { swsusp_free(); - return NULL; + return ERR_PTR(-ENOMEM); } pbe->orig_address = page_address(page); pbe->address = safe_pages_list; @@ -1868,7 +1891,10 @@ int snapshot_write_next(struct snapshot_handle *handle, size_t count) return error; } else if (handle->prev <= nr_meta_pages) { - unpack_orig_pfns(buffer, ©_bm); + error = unpack_orig_pfns(buffer, ©_bm); + if (error) + return error; + if (handle->prev == nr_meta_pages) { error = prepare_image(&orig_bm, ©_bm); if (error) @@ -1879,12 +1905,14 @@ int snapshot_write_next(struct snapshot_handle *handle, size_t count) restore_pblist = NULL; handle->buffer = get_buffer(&orig_bm, &ca); handle->sync_read = 0; - if (!handle->buffer) - return -ENOMEM; + if (IS_ERR(handle->buffer)) + return PTR_ERR(handle->buffer); } } else { copy_last_highmem_page(); handle->buffer = get_buffer(&orig_bm, &ca); + if (IS_ERR(handle->buffer)) + return PTR_ERR(handle->buffer); if (handle->buffer != buffer) handle->sync_read = 0; } diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c index 023ff2a..a92c914 100644 --- a/kernel/power/swsusp.c +++ b/kernel/power/swsusp.c @@ -262,3 +262,125 @@ int swsusp_shrink_memory(void) return 0; } + +/* + * Platforms, like ACPI, may want us to save some memory used by them during + * hibernation and to restore the contents of this memory during the subsequent + * resume. The code below implements a mechanism allowing us to do that. + */ + +struct nvs_page { + unsigned long phys_start; + unsigned int size; + void *kaddr; + void *data; + struct list_head node; +}; + +static LIST_HEAD(nvs_list); + +/** + * hibernate_nvs_register - register platform NVS memory region to save + * @start - physical address of the region + * @size - size of the region + * + * The NVS region need not be page-aligned (both ends) and we arrange + * things so that the data from page-aligned addresses in this region will + * be copied into separate RAM pages. + */ +int hibernate_nvs_register(unsigned long start, unsigned long size) +{ + struct nvs_page *entry, *next; + + while (size > 0) { + unsigned int nr_bytes; + + entry = kzalloc(sizeof(struct nvs_page), GFP_KERNEL); + if (!entry) + goto Error; + + list_add_tail(&entry->node, &nvs_list); + entry->phys_start = start; + nr_bytes = PAGE_SIZE - (start & ~PAGE_MASK); + entry->size = (size < nr_bytes) ? size : nr_bytes; + + start += entry->size; + size -= entry->size; + } + return 0; + + Error: + list_for_each_entry_safe(entry, next, &nvs_list, node) { + list_del(&entry->node); + kfree(entry); + } + return -ENOMEM; +} + +/** + * hibernate_nvs_free - free data pages allocated for saving NVS regions + */ +void hibernate_nvs_free(void) +{ + struct nvs_page *entry; + + list_for_each_entry(entry, &nvs_list, node) + if (entry->data) { + free_page((unsigned long)entry->data); + entry->data = NULL; + if (entry->kaddr) { + iounmap(entry->kaddr); + entry->kaddr = NULL; + } + } +} + +/** + * hibernate_nvs_alloc - allocate memory necessary for saving NVS regions + */ +int hibernate_nvs_alloc(void) +{ + struct nvs_page *entry; + + list_for_each_entry(entry, &nvs_list, node) { + entry->data = (void *)__get_free_page(GFP_KERNEL); + if (!entry->data) { + hibernate_nvs_free(); + return -ENOMEM; + } + } + return 0; +} + +/** + * hibernate_nvs_save - save NVS memory regions + */ +void hibernate_nvs_save(void) +{ + struct nvs_page *entry; + + printk(KERN_INFO "PM: Saving platform NVS memory\n"); + + list_for_each_entry(entry, &nvs_list, node) + if (entry->data) { + entry->kaddr = ioremap(entry->phys_start, entry->size); + memcpy(entry->data, entry->kaddr, entry->size); + } +} + +/** + * hibernate_nvs_restore - restore NVS memory regions + * + * This function is going to be called with interrupts disabled, so it + * cannot iounmap the virtual addresses used to access the NVS region. + */ +void hibernate_nvs_restore(void) +{ + struct nvs_page *entry; + + printk(KERN_INFO "PM: Restoring platform NVS memory\n"); + + list_for_each_entry(entry, &nvs_list, node) + if (entry->data) + memcpy(entry->kaddr, entry->data, entry->size); +} diff --git a/kernel/res_counter.c b/kernel/res_counter.c index f275c8e..bf8e753 100644 --- a/kernel/res_counter.c +++ b/kernel/res_counter.c @@ -15,10 +15,11 @@ #include <linux/uaccess.h> #include <linux/mm.h> -void res_counter_init(struct res_counter *counter) +void res_counter_init(struct res_counter *counter, struct res_counter *parent) { spin_lock_init(&counter->lock); counter->limit = (unsigned long long)LLONG_MAX; + counter->parent = parent; } int res_counter_charge_locked(struct res_counter *counter, unsigned long val) @@ -34,14 +35,34 @@ int res_counter_charge_locked(struct res_counter *counter, unsigned long val) return 0; } -int res_counter_charge(struct res_counter *counter, unsigned long val) +int res_counter_charge(struct res_counter *counter, unsigned long val, + struct res_counter **limit_fail_at) { int ret; unsigned long flags; - - spin_lock_irqsave(&counter->lock, flags); - ret = res_counter_charge_locked(counter, val); - spin_unlock_irqrestore(&counter->lock, flags); + struct res_counter *c, *u; + + *limit_fail_at = NULL; + local_irq_save(flags); + for (c = counter; c != NULL; c = c->parent) { + spin_lock(&c->lock); + ret = res_counter_charge_locked(c, val); + spin_unlock(&c->lock); + if (ret < 0) { + *limit_fail_at = c; + goto undo; + } + } + ret = 0; + goto done; +undo: + for (u = counter; u != c; u = u->parent) { + spin_lock(&u->lock); + res_counter_uncharge_locked(u, val); + spin_unlock(&u->lock); + } +done: + local_irq_restore(flags); return ret; } @@ -56,10 +77,15 @@ void res_counter_uncharge_locked(struct res_counter *counter, unsigned long val) void res_counter_uncharge(struct res_counter *counter, unsigned long val) { unsigned long flags; + struct res_counter *c; - spin_lock_irqsave(&counter->lock, flags); - res_counter_uncharge_locked(counter, val); - spin_unlock_irqrestore(&counter->lock, flags); + local_irq_save(flags); + for (c = counter; c != NULL; c = c->parent) { + spin_lock(&c->lock); + res_counter_uncharge_locked(c, val); + spin_unlock(&c->lock); + } + local_irq_restore(flags); } diff --git a/kernel/resource.c b/kernel/resource.c index e633106..ca6a153 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -623,7 +623,7 @@ resource_size_t resource_alignment(struct resource *res) */ struct resource * __request_region(struct resource *parent, resource_size_t start, resource_size_t n, - const char *name) + const char *name, int flags) { struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL); @@ -634,6 +634,7 @@ struct resource * __request_region(struct resource *parent, res->start = start; res->end = start + n - 1; res->flags = IORESOURCE_BUSY; + res->flags |= flags; write_lock(&resource_lock); @@ -679,7 +680,7 @@ int __check_region(struct resource *parent, resource_size_t start, { struct resource * res; - res = __request_region(parent, start, n, "check-region"); + res = __request_region(parent, start, n, "check-region", 0); if (!res) return -EBUSY; @@ -776,7 +777,7 @@ struct resource * __devm_request_region(struct device *dev, dr->start = start; dr->n = n; - res = __request_region(parent, start, n, name); + res = __request_region(parent, start, n, name, 0); if (res) devres_add(dev, dr); else @@ -876,3 +877,57 @@ int iomem_map_sanity_check(resource_size_t addr, unsigned long size) return err; } + +#ifdef CONFIG_STRICT_DEVMEM +static int strict_iomem_checks = 1; +#else +static int strict_iomem_checks; +#endif + +/* + * check if an address is reserved in the iomem resource tree + * returns 1 if reserved, 0 if not reserved. + */ +int iomem_is_exclusive(u64 addr) +{ + struct resource *p = &iomem_resource; + int err = 0; + loff_t l; + int size = PAGE_SIZE; + + if (!strict_iomem_checks) + return 0; + + addr = addr & PAGE_MASK; + + read_lock(&resource_lock); + for (p = p->child; p ; p = r_next(NULL, p, &l)) { + /* + * We can probably skip the resources without + * IORESOURCE_IO attribute? + */ + if (p->start >= addr + size) + break; + if (p->end < addr) + continue; + if (p->flags & IORESOURCE_BUSY && + p->flags & IORESOURCE_EXCLUSIVE) { + err = 1; + break; + } + } + read_unlock(&resource_lock); + + return err; +} + +static int __init strict_iomem(char *str) +{ + if (strstr(str, "relaxed")) + strict_iomem_checks = 0; + if (strstr(str, "strict")) + strict_iomem_checks = 1; + return 1; +} + +__setup("iomem=", strict_iomem); diff --git a/kernel/sched.c b/kernel/sched.c index 2e3545f..deb5ac8 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -3728,8 +3728,13 @@ redo: } double_unlock_balance(this_rq, busiest); + /* + * Should not call ttwu while holding a rq->lock + */ + spin_unlock(&this_rq->lock); if (active_balance) wake_up_process(busiest->migration_thread); + spin_lock(&this_rq->lock); } else sd->nr_balance_failed = 0; diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index e0c0b4b..8e1352c 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -1617,8 +1617,6 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued) } } -#define swap(a, b) do { typeof(a) tmp = (a); (a) = (b); (b) = tmp; } while (0) - /* * Share the fairness runtime between parent and child, thus the * total amount of pressure for CPU stays equal - new tasks diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 92f6e5b..89d7443 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -82,6 +82,9 @@ extern int percpu_pagelist_fraction; extern int compat_log; extern int latencytop_enabled; extern int sysctl_nr_open_min, sysctl_nr_open_max; +#ifndef CONFIG_MMU +extern int sysctl_nr_trim_pages; +#endif #ifdef CONFIG_RCU_TORTURE_TEST extern int rcutorture_runnable; #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */ @@ -1102,6 +1105,17 @@ static struct ctl_table vm_table[] = { .mode = 0644, .proc_handler = &proc_dointvec }, +#else + { + .ctl_name = CTL_UNNUMBERED, + .procname = "nr_trim_pages", + .data = &sysctl_nr_trim_pages, + .maxlen = sizeof(sysctl_nr_trim_pages), + .mode = 0644, + .proc_handler = &proc_dointvec_minmax, + .strategy = &sysctl_intvec, + .extra1 = &zero, + }, #endif { .ctl_name = VM_LAPTOP_MODE, diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index a9d9760..8b0daf0 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -168,7 +168,13 @@ rb_event_length(struct ring_buffer_event *event) */ unsigned ring_buffer_event_length(struct ring_buffer_event *event) { - return rb_event_length(event); + unsigned length = rb_event_length(event); + if (event->type != RINGBUF_TYPE_DATA) + return length; + length -= RB_EVNT_HDR_SIZE; + if (length > RB_MAX_SMALL_DATA + sizeof(event->array[0])) + length -= sizeof(event->array[0]); + return length; } EXPORT_SYMBOL_GPL(ring_buffer_event_length); |