Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758924AbcCVLCl (ORCPT ); Tue, 22 Mar 2016 07:02:41 -0400 Received: from mail-wm0-f66.google.com ([74.125.82.66]:35408 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932773AbcCVLBN (ORCPT ); Tue, 22 Mar 2016 07:01:13 -0400 From: Michal Hocko To: Andrew Morton Cc: , LKML , Tetsuo Handa , David Rientjes Subject: [PATCH 9/9] oom, oom_reaper: protect oom_reaper_list using simpler way Date: Tue, 22 Mar 2016 12:00:26 +0100 Message-Id: <1458644426-22973-10-git-send-email-mhocko@kernel.org> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1458644426-22973-1-git-send-email-mhocko@kernel.org> References: <1458644426-22973-1-git-send-email-mhocko@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2180 Lines: 61 From: Tetsuo Handa "oom, oom_reaper: disable oom_reaper for oom_kill_allocating_task" tried to protect oom_reaper_list using MMF_OOM_KILLED flag. But we can do it by simply checking tsk->oom_reaper_list != NULL. Signed-off-by: Tetsuo Handa Acked-by: Michal Hocko --- include/linux/sched.h | 2 -- mm/oom_kill.c | 8 ++------ 2 files changed, 2 insertions(+), 8 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index d118445a332e..78434d4f85f2 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -511,8 +511,6 @@ static inline int get_dumpable(struct mm_struct *mm) #define MMF_HAS_UPROBES 19 /* has uprobes */ #define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */ -#define MMF_OOM_KILLED 21 /* OOM killer has chosen this mm */ - #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) struct sighand_struct { diff --git a/mm/oom_kill.c b/mm/oom_kill.c index bed2885d10b0..cfafb91ebcd9 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -546,7 +546,7 @@ static int oom_reaper(void *unused) static void wake_oom_reaper(struct task_struct *tsk) { - if (!oom_reaper_th) + if (!oom_reaper_th || tsk->oom_reaper_list) return; get_task_struct(tsk); @@ -680,7 +680,7 @@ void oom_kill_process(struct oom_control *oc, struct task_struct *p, unsigned int victim_points = 0; static DEFINE_RATELIMIT_STATE(oom_rs, DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST); - bool can_oom_reap; + bool can_oom_reap = true; /* * If the task is already exiting, don't alarm the sysadmin or kill @@ -742,10 +742,6 @@ void oom_kill_process(struct oom_control *oc, struct task_struct *p, /* Get a reference to safely compare mm after task_unlock(victim) */ mm = victim->mm; atomic_inc(&mm->mm_count); - - /* Make sure we do not try to oom reap the mm multiple times */ - can_oom_reap = !test_and_set_bit(MMF_OOM_KILLED, &mm->flags); - /* * We should send SIGKILL before setting TIF_MEMDIE in order to prevent * the OOM victim from depleting the memory reserves from the user -- 2.7.0