Merge branch '3.0/pm-3' into 3.0/snapshot-mackerel-3.3-rc2
diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 26c5b11..b7dddbb 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -2456,8 +2456,9 @@
u32 poll_mask, event_mask;
unsigned int si, so;
unsigned long t;
- unsigned int change_detector, must_reset;
+ unsigned int change_detector;
unsigned int poll_freq;
+ bool was_frozen;
mutex_lock(&hotkey_thread_mutex);
@@ -2488,14 +2489,14 @@
t = 100; /* should never happen... */
}
t = msleep_interruptible(t);
- if (unlikely(kthread_should_stop()))
+ if (unlikely(kthread_freezable_should_stop(&was_frozen)))
break;
- must_reset = try_to_freeze();
- if (t > 0 && !must_reset)
+
+ if (t > 0 && !was_frozen)
continue;
mutex_lock(&hotkey_thread_data_mutex);
- if (must_reset || hotkey_config_change != change_detector) {
+ if (was_frozen || hotkey_config_change != change_detector) {
/* forget old state on thaw or config change */
si = so;
t = 0;
@@ -2528,10 +2529,6 @@
static void hotkey_poll_stop_sync(void)
{
if (tpacpi_hotkey_task) {
- if (frozen(tpacpi_hotkey_task) ||
- freezing(tpacpi_hotkey_task))
- thaw_process(tpacpi_hotkey_task);
-
kthread_stop(tpacpi_hotkey_task);
tpacpi_hotkey_task = NULL;
mutex_lock(&hotkey_thread_mutex);
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 0f015a0..41b02b3 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -903,7 +903,7 @@
trace_writeback_thread_start(bdi);
- while (!kthread_should_stop()) {
+ while (!kthread_freezable_should_stop(NULL)) {
/*
* Remove own delayed wake-up timer, since we are already awake
* and we'll take care of the preriodic write-back.
@@ -933,8 +933,6 @@
*/
schedule();
}
-
- try_to_freeze();
}
/* Flush any work that raced with us exiting */
diff --git a/include/linux/freezer.h b/include/linux/freezer.h
index eb9c977..05231b7 100644
--- a/include/linux/freezer.h
+++ b/include/linux/freezer.h
@@ -5,8 +5,13 @@
#include <linux/sched.h>
#include <linux/wait.h>
+#include <linux/atomic.h>
#ifdef CONFIG_FREEZER
+extern atomic_t system_freezing_cnt; /* nr of freezing conds in effect */
+extern bool pm_freezing; /* PM freezing in effect */
+extern bool pm_nosig_freezing; /* PM nosig freezing in effect */
+
/*
* Check if a process has been frozen
*/
@@ -15,28 +20,16 @@
return p->flags & PF_FROZEN;
}
+extern bool freezing_slow_path(struct task_struct *p);
+
/*
* Check if there is a request to freeze a process
*/
-static inline int freezing(struct task_struct *p)
+static inline bool freezing(struct task_struct *p)
{
- return test_tsk_thread_flag(p, TIF_FREEZE);
-}
-
-/*
- * Request that a process be frozen
- */
-static inline void set_freeze_flag(struct task_struct *p)
-{
- set_tsk_thread_flag(p, TIF_FREEZE);
-}
-
-/*
- * Sometimes we may need to cancel the previous 'freeze' request
- */
-static inline void clear_freeze_flag(struct task_struct *p)
-{
- clear_tsk_thread_flag(p, TIF_FREEZE);
+ if (likely(!atomic_read(&system_freezing_cnt)))
+ return false;
+ return freezing_slow_path(p);
}
static inline bool should_send_signal(struct task_struct *p)
@@ -45,30 +38,30 @@
}
/* Takes and releases task alloc lock using task_lock() */
-extern int thaw_process(struct task_struct *p);
+extern void __thaw_task(struct task_struct *t);
-extern bool __refrigerator(void);
+extern bool __refrigerator(bool check_kthr_stop);
extern int freeze_processes(void);
extern int freeze_kernel_threads(void);
extern void thaw_processes(void);
+extern void thaw_kernel_threads(void);
static inline bool try_to_freeze(void)
{
might_sleep();
if (likely(!freezing(current)))
return false;
- return __refrigerator();
+ return __refrigerator(false);
}
extern bool freeze_task(struct task_struct *p, bool sig_only);
-extern void cancel_freezing(struct task_struct *p);
#ifdef CONFIG_CGROUP_FREEZER
-extern int cgroup_freezing_or_frozen(struct task_struct *task);
+extern bool cgroup_freezing(struct task_struct *task);
#else /* !CONFIG_CGROUP_FREEZER */
-static inline int cgroup_freezing_or_frozen(struct task_struct *task)
+static inline bool cgroup_freezing(struct task_struct *task)
{
- return 0;
+ return false;
}
#endif /* !CONFIG_CGROUP_FREEZER */
@@ -165,15 +158,13 @@
})
#else /* !CONFIG_FREEZER */
static inline int frozen(struct task_struct *p) { return 0; }
-static inline int freezing(struct task_struct *p) { return 0; }
-static inline void set_freeze_flag(struct task_struct *p) {}
-static inline void clear_freeze_flag(struct task_struct *p) {}
-static inline int thaw_process(struct task_struct *p) { return 1; }
+static inline bool freezing(struct task_struct *p) { return false; }
-static inline bool __refrigerator(void) { return false; }
+static inline bool __refrigerator(bool check_kthr_stop) { return false; }
static inline int freeze_processes(void) { return -ENOSYS; }
static inline int freeze_kernel_threads(void) { return -ENOSYS; }
static inline void thaw_processes(void) {}
+static inline void thaw_kernel_threads(void) {}
static inline bool try_to_freeze(void) { return false; }
diff --git a/include/linux/kthread.h b/include/linux/kthread.h
index 1e923e5..6c1903d 100644
--- a/include/linux/kthread.h
+++ b/include/linux/kthread.h
@@ -35,6 +35,7 @@
void kthread_bind(struct task_struct *k, unsigned int cpu);
int kthread_stop(struct task_struct *k);
int kthread_should_stop(void);
+bool kthread_freezable_should_stop(bool *was_frozen);
void *kthread_data(struct task_struct *k);
int kthreadd(void *unused);
diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c
index e691818..5f45423 100644
--- a/kernel/cgroup_freezer.c
+++ b/kernel/cgroup_freezer.c
@@ -48,19 +48,17 @@
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 @@
* 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 @@
* 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 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);
}
/*
@@ -177,13 +176,7 @@
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;
+ return cgroup_freezing(tsk) ? -EBUSY : 0;
}
static void freezer_fork(struct cgroup_subsys *ss, struct task_struct *task)
@@ -231,7 +224,7 @@
cgroup_iter_start(cgroup, &it);
while ((task = cgroup_iter_next(cgroup, &it))) {
ntotal++;
- if (frozen(task))
+ if (freezing(task) && frozen(task))
nfrozen++;
}
@@ -279,7 +272,6 @@
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))
@@ -300,12 +292,9 @@
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,
@@ -319,20 +308,24 @@
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;
diff --git a/kernel/exit.c b/kernel/exit.c
index f2b321b..46c334e 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -693,8 +693,6 @@
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);
if (tsk->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
atomic_dec(&mm->oom_disable_count);
task_unlock(tsk);
@@ -1051,6 +1049,7 @@
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". */
diff --git a/kernel/fork.c b/kernel/fork.c
index 7517a53..b7a25b8 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -999,7 +999,6 @@
new_flags |= PF_FORKNOEXEC;
new_flags |= PF_STARTING;
p->flags = new_flags;
- clear_freeze_flag(p);
}
SYSCALL_DEFINE1(set_tid_address, int __user *, tidptr)
diff --git a/kernel/freezer.c b/kernel/freezer.c
index 4d59904..8bf25f4 100644
--- a/kernel/freezer.c
+++ b/kernel/freezer.c
@@ -9,35 +9,60 @@
#include <linux/module.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_FREEZER_NOSIG))
+ return true;
+
+ return false;
}
+EXPORT_SYMBOL(freezing_slow_path);
/* Refrigerator is place where frozen processes are stored :-). */
-bool __refrigerator(void)
+bool __refrigerator(bool check_kthr_stop)
{
/* Hmm, should we be allowed to suspend when there are realtime
processes around? */
bool was_frozen = false;
long save;
- task_lock(current);
- if (freezing(current)) {
- frozen_process();
- task_unlock(current);
- } else {
- task_unlock(current);
- return was_frozen;
- }
+ /*
+ * No point in checking freezing() again - the caller already did.
+ * Proceed to enter FROZEN.
+ */
+ spin_lock_irq(&freezer_lock);
+repeat:
+ current->flags |= PF_FROZEN;
+ spin_unlock_irq(&freezer_lock);
+
save = current->state;
pr_debug("%s entered refrigerator\n", current->comm);
@@ -50,7 +75,8 @@
for (;;) {
set_current_state(TASK_UNINTERRUPTIBLE);
- if (!frozen(current))
+ if (!freezing(current) ||
+ (check_kthr_stop && kthread_should_stop()))
break;
was_frozen = true;
schedule();
@@ -59,6 +85,13 @@
/* Remove the accounting blocker */
current->flags &= ~PF_FREEZING;
+ /* leave FROZEN */
+ spin_lock_irq(&freezer_lock);
+ if (freezing(current))
+ goto repeat;
+ current->flags &= ~PF_FROZEN;
+ spin_unlock_irq(&freezer_lock);
+
pr_debug("%s left refrigerator\n", current->comm);
/*
@@ -97,20 +130,12 @@
*/
bool freeze_task(struct task_struct *p, bool sig_only)
{
- /*
- * 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;
+ unsigned long flags;
- if (!sig_only || should_send_signal(p))
- set_freeze_flag(p);
- else
- return false;
+ spin_lock_irqsave(&freezer_lock, flags);
+ if (!freezing(p) || frozen(p)) {
+ spin_unlock_irqrestore(&freezer_lock, flags);
+ return false;
}
if (should_send_signal(p)) {
@@ -121,56 +146,34 @@
* 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)
-{
+ /*
+ * 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.
+ *
+ * If !FROZEN, @p hasn't reached refrigerator, recalc sigpending to
+ * avoid leaving dangling TIF_SIGPENDING behind.
+ */
+ spin_lock_irqsave(&freezer_lock, flags);
if (frozen(p)) {
- p->flags &= ~PF_FROZEN;
- return 1;
- }
- clear_freeze_flag(p);
- return 0;
-}
-
-/*
- * Wake up a frozen process
- *
- * 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.
- */
-int thaw_process(struct task_struct *p)
-{
- task_lock(p);
- if (__thaw_process(p) == 1) {
- task_unlock(p);
wake_up_process(p);
- return 1;
+ } else {
+ spin_lock(&p->sighand->siglock);
+ recalc_sigpending_and_wake(p);
+ spin_unlock(&p->sighand->siglock);
}
- task_unlock(p);
- return 0;
+ spin_unlock_irqrestore(&freezer_lock, flags);
}
-EXPORT_SYMBOL(thaw_process);
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 4ba7ccc..a6cbeea 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -59,6 +59,31 @@
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
*
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 3a20466..3e51ae4 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -590,17 +590,6 @@
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.
*/
@@ -633,7 +622,7 @@
sys_sync();
printk("done.\n");
- error = prepare_processes();
+ error = freeze_processes();
if (error)
goto Finish;
@@ -780,7 +769,7 @@
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;
diff --git a/kernel/power/process.c b/kernel/power/process.c
index addbbe5..de80222 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -22,15 +22,6 @@
*/
#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)
{
struct task_struct *g, *p;
@@ -53,10 +44,7 @@
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, sig_only))
continue;
/*
@@ -103,11 +91,6 @@
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 @@
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 @@
/**
* 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 @@
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.");
@@ -168,38 +158,52 @@
printk("\n");
BUG_ON(in_atomic());
+ if (error)
+ thaw_processes();
return error;
}
-static void thaw_tasks(bool nosig_only)
-{
- struct task_struct *g, *p;
-
- read_lock(&tasklist_lock);
- do_each_thread(g, p) {
- if (!freezable(p))
- continue;
-
- if (nosig_only && should_send_signal(p))
- continue;
-
- if (cgroup_freezing_or_frozen(p))
- continue;
-
- thaw_process(p);
- } while_each_thread(g, p);
- read_unlock(&tasklist_lock);
-}
-
void thaw_processes(void)
{
+ struct task_struct *g, *p;
+
+ if (pm_freezing)
+ atomic_dec(&system_freezing_cnt);
+ pm_freezing = false;
+ pm_nosig_freezing = false;
+
oom_killer_enable();
printk("Restarting tasks ... ");
+
thaw_workqueues();
- thaw_tasks(true);
- thaw_tasks(false);
+
+ read_lock(&tasklist_lock);
+ do_each_thread(g, p) {
+ __thaw_task(p);
+ } while_each_thread(g, p);
+ read_unlock(&tasklist_lock);
+
schedule();
printk("done.\n");
}
+void thaw_kernel_threads(void)
+{
+ struct task_struct *g, *p;
+
+ pm_nosig_freezing = false;
+ printk("Restarting kernel threads ... ");
+
+ thaw_workqueues();
+
+ read_lock(&tasklist_lock);
+ do_each_thread(g, p) {
+ if (p->flags & (PF_KTHREAD | PF_WQ_WORKER))
+ __thaw_task(p);
+ } while_each_thread(g, p);
+ read_unlock(&tasklist_lock);
+
+ schedule();
+ printk("done.\n");
+}
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 06efa54..2e1184d 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -812,7 +812,8 @@
unsigned int res;
res = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK);
- res += DIV_ROUND_UP(res * sizeof(struct bm_block), PAGE_SIZE);
+ res += DIV_ROUND_UP(res * sizeof(struct bm_block),
+ LINKED_PAGE_DATA_SIZE);
return 2 * res;
}
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 609493b..c6d5dde 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -102,13 +102,11 @@
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/user.c b/kernel/power/user.c
index 42ddbc6..370574b 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -256,10 +256,8 @@
break;
error = freeze_processes();
- if (error) {
- thaw_processes();
+ if (error)
usermodehelper_enable();
- }
if (!error)
data->frozen = 1;
break;
@@ -302,6 +300,15 @@
swsusp_free();
memset(&data->handle, 0, sizeof(struct snapshot_handle));
data->ready = 0;
+ /*
+ * It is necessary to thaw kernel threads here, because
+ * SNAPSHOT_CREATE_IMAGE may be invoked directly after
+ * SNAPSHOT_FREE. In that case, if kernel threads were not
+ * thawed, the preallocation of memory carried out by
+ * hibernation_snapshot() might run into problems (i.e. it
+ * might fail or even deadlock).
+ */
+ thaw_kernel_threads();
break;
case SNAPSHOT_SET_IMAGE_SIZE:
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index f032e6e..a7872d1 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -578,14 +578,10 @@
/*
* Finally, kill the kernel thread. We don't need to be RCU
- * safe anymore, since the bdi is gone from visibility. Force
- * unfreeze of the thread before calling kthread_stop(), otherwise
- * it would never exet if it is currently stuck in the refrigerator.
+ * safe anymore, since the bdi is gone from visibility.
*/
- if (bdi->wb.task) {
- thaw_process(bdi->wb.task);
+ if (bdi->wb.task)
kthread_stop(bdi->wb.task);
- }
}
/*
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index e4b0991..61686128 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -32,6 +32,7 @@
#include <linux/mempolicy.h>
#include <linux/security.h>
#include <linux/ptrace.h>
+#include <linux/freezer.h>
int sysctl_panic_on_oom;
int sysctl_oom_kill_allocating_task;
@@ -303,7 +304,7 @@
do_each_thread(g, p) {
unsigned int points;
- if (!p->mm)
+ if (p->exit_state)
continue;
if (oom_unkillable_task(p, mem, nodemask))
continue;
@@ -317,8 +318,13 @@
* blocked waiting for another task which itself is waiting
* for memory. Is there a better alternative?
*/
- if (test_tsk_thread_flag(p, TIF_MEMDIE))
+ if (test_tsk_thread_flag(p, TIF_MEMDIE)) {
+ if (unlikely(frozen(p)))
+ __thaw_task(p);
return ERR_PTR(-1UL);
+ }
+ if (!p->mm)
+ continue;
if (p->flags & PF_EXITING) {
/*
