From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta7.messagelabs.com (mail6.bemta7.messagelabs.com [216.82.255.55]) by kanga.kvack.org (Postfix) with ESMTP id ACA596B002D for ; Wed, 9 Nov 2011 04:09:23 -0500 (EST) From: Michal Hocko Date: Fri, 4 Nov 2011 12:59:44 +0100 Subject: [PATCH resend] oom: do not kill tasks with oom_score_adj OOM_SCORE_ADJ_MIN Message-Id: <20111109090919.C2D538AD27@mx2.suse.de> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, David Rientjes , KOSAKI Motohiro , Oleg Nesterov , Ying Han c9f01245 (oom: remove oom_disable_count) has removed oom_disable_count counter which has been used for early break out from oom_badness so we could never select a task with oom_score_adj set to OOM_SCORE_ADJ_MIN (oom disabled). Now that the counter is gone we are always going through heuristics calculation and we always return a non zero positive value. This means that we can end up killing a task with OOM disabled because it is indistinguishable from regular tasks with 1% resp. CAP_SYS_ADMIN tasks with 3% usage of memory or tasks with oom_score_adj set but OOM enabled. Let's break out early if the task should have OOM disabled. Signed-off-by: Michal Hocko Acked-by: David Rientjes Acked-by: KOSAKI Motohiro --- mm/oom_kill.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/mm/oom_kill.c b/mm/oom_kill.c index e916168..4465fb8 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -185,6 +185,11 @@ unsigned int oom_badness(struct task_struct *p, struct mem_cgroup *mem, if (!p) return 0; + if (p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) { + task_unlock(p); + return 0; + } + /* * The memory controller may have a limit of 0 bytes, so avoid a divide * by zero, if necessary. -- 1.7.7.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org