diff options
Diffstat (limited to 'mm/oom_kill.c')
| -rw-r--r-- | mm/oom_kill.c | 34 |
1 files changed, 19 insertions, 15 deletions
diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 415f7eb913fa..5bb2f7698ad7 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -174,8 +174,13 @@ unsigned long oom_badness(struct task_struct *p, struct mem_cgroup *memcg, if (!p) return 0; + /* + * Do not even consider tasks which are explicitly marked oom + * unkillable or have been already oom reaped. + */ adj = (long)p->signal->oom_score_adj; - if (adj == OOM_SCORE_ADJ_MIN) { + if (adj == OOM_SCORE_ADJ_MIN || + test_bit(MMF_OOM_REAPED, &p->mm->flags)) { task_unlock(p); return 0; } @@ -278,12 +283,8 @@ enum oom_scan_t oom_scan_process_thread(struct oom_control *oc, * This task already has access to memory reserves and is being killed. * Don't allow any other task to have access to the reserves. */ - if (test_tsk_thread_flag(task, TIF_MEMDIE)) { - if (!is_sysrq_oom(oc)) - return OOM_SCAN_ABORT; - } - if (!task->mm) - return OOM_SCAN_CONTINUE; + if (!is_sysrq_oom(oc) && atomic_read(&task->signal->oom_victims)) + return OOM_SCAN_ABORT; /* * If task is allocating a lot of memory and has been marked to be @@ -302,12 +303,12 @@ enum oom_scan_t oom_scan_process_thread(struct oom_control *oc, static struct task_struct *select_bad_process(struct oom_control *oc, unsigned int *ppoints, unsigned long totalpages) { - struct task_struct *g, *p; + struct task_struct *p; struct task_struct *chosen = NULL; unsigned long chosen_points = 0; rcu_read_lock(); - for_each_process_thread(g, p) { + for_each_process(p) { unsigned int points; switch (oom_scan_process_thread(oc, p, totalpages)) { @@ -326,9 +327,6 @@ static struct task_struct *select_bad_process(struct oom_control *oc, points = oom_badness(p, NULL, oc->nodemask, totalpages); if (!points || points < chosen_points) continue; - /* Prefer thread group leaders for display purposes */ - if (points == chosen_points && thread_group_leader(chosen)) - continue; chosen = p; chosen_points = points; @@ -441,7 +439,6 @@ static DECLARE_WAIT_QUEUE_HEAD(oom_reaper_wait); static struct task_struct *oom_reaper_list; static DEFINE_SPINLOCK(oom_reaper_lock); - static bool __oom_reap_task(struct task_struct *tsk) { struct mmu_gather tlb; @@ -513,9 +510,14 @@ static bool __oom_reap_task(struct task_struct *tsk) * This task can be safely ignored because we cannot do much more * to release its memory. */ - tsk->signal->oom_score_adj = OOM_SCORE_ADJ_MIN; + set_bit(MMF_OOM_REAPED, &mm->flags); out: - mmput(mm); + /* + * Drop our reference but make sure the mmput slow path is called from a + * different context because we shouldn't risk we get stuck there and + * put the oom_reaper out of the way. + */ + mmput_async(mm); return ret; } @@ -664,6 +666,7 @@ void mark_oom_victim(struct task_struct *tsk) /* OOM killer might race with memcg OOM */ if (test_and_set_tsk_thread_flag(tsk, TIF_MEMDIE)) return; + atomic_inc(&tsk->signal->oom_victims); /* * Make sure that the task is woken up from uninterruptible sleep * if it is frozen because OOM killer wouldn't be able to free @@ -681,6 +684,7 @@ void exit_oom_victim(struct task_struct *tsk) { if (!test_and_clear_tsk_thread_flag(tsk, TIF_MEMDIE)) return; + atomic_dec(&tsk->signal->oom_victims); if (!atomic_dec_return(&oom_victims)) wake_up_all(&oom_victims_wait); |