From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with ESMTP id 8E8276B0210 for ; Sun, 4 Apr 2010 19:28:09 -0400 (EDT) Received: from wpaz17.hot.corp.google.com (wpaz17.hot.corp.google.com [172.24.198.81]) by smtp-out.google.com with ESMTP id o34NS5Tn014133 for ; Mon, 5 Apr 2010 01:28:05 +0200 Received: from pzk8 (pzk8.prod.google.com [10.243.19.136]) by wpaz17.hot.corp.google.com with ESMTP id o34NS3vR013741 for ; Sun, 4 Apr 2010 16:28:04 -0700 Received: by pzk8 with SMTP id 8so5193pzk.16 for ; Sun, 04 Apr 2010 16:28:03 -0700 (PDT) Date: Sun, 4 Apr 2010 16:28:01 -0700 (PDT) From: David Rientjes Subject: Re: [patch -mm] memcg: make oom killer a no-op when no killable task can be found In-Reply-To: Message-ID: References: <20100328145528.GA14622@desktop> <20100328162821.GA16765@redhat.com> <20100329140633.GA26464@desktop> <20100330142923.GA10099@desktop> <20100331095714.9137caab.kamezawa.hiroyu@jp.fujitsu.com> <20100331151356.673c16c0.kamezawa.hiroyu@jp.fujitsu.com> <20100331063007.GN3308@balbir.in.ibm.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Andrew Morton Cc: KAMEZAWA Hiroyuki , anfei , KOSAKI Motohiro , nishimura@mxp.nes.nec.co.jp, Balbir Singh , linux-mm@kvack.org List-ID: On Wed, 31 Mar 2010, David Rientjes wrote: > It's pointless to try to kill current if select_bad_process() did not > find an eligible task to kill in mem_cgroup_out_of_memory() since it's > guaranteed that current is a member of the memcg that is oom and it is, > by definition, unkillable. > > Signed-off-by: David Rientjes > --- > mm/oom_kill.c | 5 +---- > 1 files changed, 1 insertions(+), 4 deletions(-) > > diff --git a/mm/oom_kill.c b/mm/oom_kill.c > --- a/mm/oom_kill.c > +++ b/mm/oom_kill.c > @@ -500,12 +500,9 @@ void mem_cgroup_out_of_memory(struct mem_cgroup *mem, gfp_t gfp_mask) > read_lock(&tasklist_lock); > retry: > p = select_bad_process(&points, limit, mem, CONSTRAINT_NONE, NULL); > - if (PTR_ERR(p) == -1UL) > + if (!p || PTR_ERR(p) == -1UL) > goto out; > > - if (!p) > - p = current; > - > if (oom_kill_process(p, gfp_mask, 0, points, limit, mem, > "Memory cgroup out of memory")) > goto retry; > Are there any objections to merging this? It's pretty straight-forward given the fact that oom_kill_process() would fail if select_bad_process() returns NULL even if p is set to current since it was not found to be eligible during the tasklist scan. -- 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/ . Don't email: email@kvack.org