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Date: Tue, 30 Mar 2010 23:32:35 -0700 (PDT)
From: David Rientjes <rientjes@google.com>
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To: Balbir Singh <balbir@linux.vnet.ibm.com>
cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
       anfei <anfei.zhou@gmail.com>, Oleg Nesterov <oleg@redhat.com>,
       Andrew Morton <akpm@linux-foundation.org>,
       KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
       nishimura@mxp.nes.nec.co.jp, Mel Gorman <mel@csn.ul.ie>,
       linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] oom killer: break from infinite loop
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On Wed, 31 Mar 2010, Balbir Singh wrote:

> > To me, this patch is acceptable and seems reasnoable.
> > 
> > But I didn't joined to memcg development when this check was added
> > and don't know why kill current..
> >
> 
> The reason for adding current was that we did not want to loop
> forever, since it stops forward progress - no error/no forward
> progress. It made sense to oom kill the current process, so that the
> cgroup admin could look at what went wrong.
>  

oom_kill_process() will fail on current since it wasn't selected as an 
eligible task to kill in select_bad_process() and we know it to be a 
member of the memcg, so there's no point in trying to kill it.