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Date: Fri, 2 Apr 2010 12:46:32 -0700 (PDT)
From: David Rientjes <rientjes@google.com>
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To: Oleg Nesterov <oleg@redhat.com>
cc: Andrew Morton <akpm@linux-foundation.org>, anfei <anfei.zhou@gmail.com>,
       KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
       nishimura@mxp.nes.nec.co.jp,
       KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
       Mel Gorman <mel@csn.ul.ie>, linux-mm@kvack.org,
       linux-kernel@vger.kernel.org
Subject: Re: [patch] oom: give current access to memory reserves if it has
 been killed
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On Fri, 2 Apr 2010, Oleg Nesterov wrote:

> > > David, you continue to ignore my arguments ;) select_bad_process()
> > > must not filter out the tasks with ->mm == NULL.
> > >
> > I'm not ignoring your arguments, I think you're ignoring what I'm
> > responding to.
> 
> Ah, sorry, I misunderstood your replies.
> 
> > I prefer to keep oom_badness() to be a positive range as
> > it always has been (and /proc/pid/oom_score has always used an unsigned
> > qualifier),
> 
> Yes, I thought about /proc/pid/oom_score, but imho this is minor issue.
> We can s/%lu/%ld/ though, or just report 0 if oom_badness() returns -1.
> Or something.
> 

Just have it return 0, meaning never kill, and then ensure "chosen" is 
never set for an oom_badness() of 0, even if we don't have another task to 
kill.  That's how Documentation/filesystems/proc.txt describes it anyway.