From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with ESMTP id 9FB716B01E3 for ; Mon, 5 Apr 2010 17:31:26 -0400 (EDT) Date: Mon, 5 Apr 2010 14:30:59 -0700 From: Andrew Morton Subject: Re: [patch -mm] memcg: make oom killer a no-op when no killable task can be found Message-Id: <20100405143059.3b56862f.akpm@linux-foundation.org> In-Reply-To: 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 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: David Rientjes Cc: KAMEZAWA Hiroyuki , anfei , KOSAKI Motohiro , nishimura@mxp.nes.nec.co.jp, Balbir Singh , linux-mm@kvack.org List-ID: On Sun, 4 Apr 2010 16:28:01 -0700 (PDT) David Rientjes wrote: > 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. I've lost the plot on the oom-killer patches. Half the things I'm seeing don't even apply. Perhaps I should drop the lot and we start again. We still haven't resolved the procfs back-compat issue, either. -- 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