diff options
| -rw-r--r-- | include/linux/oom.h | 2 | ||||
| -rw-r--r-- | kernel/power/process.c | 17 | ||||
| -rw-r--r-- | mm/oom_kill.c | 40 |
3 files changed, 24 insertions, 35 deletions
diff --git a/include/linux/oom.h b/include/linux/oom.h index b61357d07170..0f1b9da108e4 100644 --- a/include/linux/oom.h +++ b/include/linux/oom.h @@ -74,7 +74,7 @@ extern void exit_oom_victim(struct task_struct *tsk); extern int register_oom_notifier(struct notifier_block *nb); extern int unregister_oom_notifier(struct notifier_block *nb); -extern bool oom_killer_disable(void); +extern bool oom_killer_disable(signed long timeout); extern void oom_killer_enable(void); extern struct task_struct *find_lock_task_mm(struct task_struct *p); diff --git a/kernel/power/process.c b/kernel/power/process.c index 8f27d5a8adf6..2fba066e125f 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -144,23 +144,12 @@ int freeze_processes(void) /* * Now that the whole userspace is frozen we need to disbale * the OOM killer to disallow any further interference with - * killable tasks. + * killable tasks. There is no guarantee oom victims will + * ever reach a point they go away we have to wait with a timeout. */ - if (!error && !oom_killer_disable()) + if (!error && !oom_killer_disable(msecs_to_jiffies(freeze_timeout_msecs))) error = -EBUSY; - /* - * There is a hard to fix race between oom_reaper kernel thread - * and oom_killer_disable. oom_reaper calls exit_oom_victim - * before the victim reaches exit_mm so try to freeze all the tasks - * again and catch such a left over task. - */ - if (!error) { - pr_info("Double checking all user space processes after OOM killer disable... "); - error = try_to_freeze_tasks(true); - pr_cont("\n"); - } - if (error) thaw_processes(); return error; diff --git a/mm/oom_kill.c b/mm/oom_kill.c index e2a2c35dd493..895a51fe8e18 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -559,14 +559,7 @@ static void oom_reap_task(struct task_struct *tsk) debug_show_all_locks(); done: - /* - * Clear TIF_MEMDIE because the task shouldn't be sitting on a - * reasonably reclaimable memory anymore or it is not a good candidate - * for the oom victim right now because it cannot release its memory - * itself nor by the oom reaper. - */ tsk->oom_reaper_list = NULL; - exit_oom_victim(tsk); /* * Hide this mm from OOM killer because it has been either reaped or @@ -580,8 +573,6 @@ done: static int oom_reaper(void *unused) { - set_freezable(); - while (true) { struct task_struct *tsk = NULL; @@ -681,10 +672,20 @@ void exit_oom_victim(struct task_struct *tsk) } /** + * oom_killer_enable - enable OOM killer + */ +void oom_killer_enable(void) +{ + oom_killer_disabled = false; +} + +/** * oom_killer_disable - disable OOM killer + * @timeout: maximum timeout to wait for oom victims in jiffies * * Forces all page allocations to fail rather than trigger OOM killer. - * Will block and wait until all OOM victims are killed. + * Will block and wait until all OOM victims are killed or the given + * timeout expires. * * The function cannot be called when there are runnable user tasks because * the userspace would see unexpected allocation failures as a result. Any @@ -693,8 +694,10 @@ void exit_oom_victim(struct task_struct *tsk) * Returns true if successful and false if the OOM killer cannot be * disabled. */ -bool oom_killer_disable(void) +bool oom_killer_disable(signed long timeout) { + signed long ret; + /* * Make sure to not race with an ongoing OOM killer. Check that the * current is not killed (possibly due to sharing the victim's memory). @@ -704,19 +707,16 @@ bool oom_killer_disable(void) oom_killer_disabled = true; mutex_unlock(&oom_lock); - wait_event(oom_victims_wait, !atomic_read(&oom_victims)); + ret = wait_event_interruptible_timeout(oom_victims_wait, + !atomic_read(&oom_victims), timeout); + if (ret <= 0) { + oom_killer_enable(); + return false; + } return true; } -/** - * oom_killer_enable - enable OOM killer - */ -void oom_killer_enable(void) -{ - oom_killer_disabled = false; -} - static inline bool __task_will_free_mem(struct task_struct *task) { struct signal_struct *sig = task->signal; |