From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with ESMTP id DD6AA8D0039 for ; Wed, 9 Mar 2011 16:28:00 -0500 (EST) Received: from wpaz1.hot.corp.google.com (wpaz1.hot.corp.google.com [172.24.198.65]) by smtp-out.google.com with ESMTP id p29LRurG020119 for ; Wed, 9 Mar 2011 13:27:57 -0800 Received: from ywa8 (ywa8.prod.google.com [10.192.1.8]) by wpaz1.hot.corp.google.com with ESMTP id p29LRtYo015203 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for ; Wed, 9 Mar 2011 13:27:55 -0800 Received: by ywa8 with SMTP id 8so446178ywa.8 for ; Wed, 09 Mar 2011 13:27:55 -0800 (PST) Date: Wed, 9 Mar 2011 13:27:50 -0800 (PST) From: David Rientjes Subject: [patch] memcg: give current access to memory reserves if it's trying to die In-Reply-To: Message-ID: References: <20110307171853.c31ec416.akpm@linux-foundation.org> <20110308115108.36b184c5.kamezawa.hiroyu@jp.fujitsu.com> <20110308121332.de003f81.kamezawa.hiroyu@jp.fujitsu.com> <20110308131723.e434cb89.kamezawa.hiroyu@jp.fujitsu.com> <20110308144901.fe34abd0.kamezawa.hiroyu@jp.fujitsu.com> <20110309150452.29883939.kamezawa.hiroyu@jp.fujitsu.com> <20110309161621.f890c148.kamezawa.hiroyu@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , KAMEZAWA Hiroyuki Cc: Balbir Singh , Daisuke Nishimura , linux-mm@kvack.org When a memcg is oom and current has already received a SIGKILL, then give it access to memory reserves with a higher scheduling priority so that it may quickly exit and free its memory. This is identical to the global oom killer and is done even before checking for panic_on_oom: a pending SIGKILL here while panic_on_oom is selected is guaranteed to have come from userspace; the thread only needs access to memory reserves to exit and thus we don't unnecessarily panic the machine until the kernel has no last resort to free memory. Signed-off-by: David Rientjes --- mm/oom_kill.c | 11 +++++++++++ 1 files changed, 11 insertions(+), 0 deletions(-) diff --git a/mm/oom_kill.c b/mm/oom_kill.c --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -537,6 +537,17 @@ void mem_cgroup_out_of_memory(struct mem_cgroup *mem, gfp_t gfp_mask) unsigned int points = 0; struct task_struct *p; + /* + * If current has a pending SIGKILL, then automatically select it. The + * goal is to allow it to allocate so that it may quickly exit and free + * its memory. + */ + if (fatal_signal_pending(current)) { + set_thread_flag(TIF_MEMDIE); + boost_dying_task_prio(current, NULL); + return; + } + check_panic_on_oom(CONSTRAINT_MEMCG, gfp_mask, 0, NULL); limit = mem_cgroup_get_limit(mem) >> PAGE_SHIFT; read_lock(&tasklist_lock); -- 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