diff options
| -rw-r--r-- | include/linux/sched.h | 3 | ||||
| -rw-r--r-- | mm/oom_kill.c | 36 |
2 files changed, 22 insertions, 17 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index 478b41de7f7d..788f223f8f8f 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1849,6 +1849,9 @@ struct task_struct { unsigned long task_state_change; #endif int pagefault_disabled; +#ifdef CONFIG_MMU + struct list_head oom_reaper_list; +#endif /* CPU-specific state of this task */ struct thread_struct thread; /* diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 30a60991173a..f6d4ae9f1c69 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -418,8 +418,10 @@ bool oom_killer_disabled __read_mostly; * victim (if that is possible) to help the OOM killer to move on. */ static struct task_struct *oom_reaper_th; -static struct task_struct *task_to_reap; static DECLARE_WAIT_QUEUE_HEAD(oom_reaper_wait); +static LIST_HEAD(oom_reaper_list); +static DEFINE_SPINLOCK(oom_reaper_lock); + static bool __oom_reap_task(struct task_struct *tsk) { @@ -524,12 +526,20 @@ static void oom_reap_task(struct task_struct *tsk) static int oom_reaper(void *unused) { while (true) { - struct task_struct *tsk; + struct task_struct *tsk = NULL; wait_event_freezable(oom_reaper_wait, - (tsk = READ_ONCE(task_to_reap))); - oom_reap_task(tsk); - WRITE_ONCE(task_to_reap, NULL); + (!list_empty(&oom_reaper_list))); + spin_lock(&oom_reaper_lock); + if (!list_empty(&oom_reaper_list)) { + tsk = list_first_entry(&oom_reaper_list, + struct task_struct, oom_reaper_list); + list_del(&tsk->oom_reaper_list); + } + spin_unlock(&oom_reaper_lock); + + if (tsk) + oom_reap_task(tsk); } return 0; @@ -537,23 +547,15 @@ static int oom_reaper(void *unused) static void wake_oom_reaper(struct task_struct *tsk) { - struct task_struct *old_tsk; - if (!oom_reaper_th) return; get_task_struct(tsk); - /* - * Make sure that only a single mm is ever queued for the reaper - * because multiple are not necessary and the operation might be - * disruptive so better reduce it to the bare minimum. - */ - old_tsk = cmpxchg(&task_to_reap, NULL, tsk); - if (!old_tsk) - wake_up(&oom_reaper_wait); - else - put_task_struct(tsk); + spin_lock(&oom_reaper_lock); + list_add(&tsk->oom_reaper_list, &oom_reaper_list); + spin_unlock(&oom_reaper_lock); + wake_up(&oom_reaper_wait); } static int __init oom_init(void) |