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Date: Sun, 7 Jun 2009 19:42:28 +0530
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Subject: Re: [patch -mmotm] oom: only oom kill exiting tasks with attached 
	memory
From: Balbir Singh <balbir@linux.vnet.ibm.com>
To: David Rientjes <rientjes@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Rik van Riel <riel@redhat.com>,
       linux-kernel@vger.kernel.org
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On Sun, Jun 7, 2009 at 3:42 AM, David Rientjes<rientjes@google.com> wrote:
> When a task is chosen for oom kill and is found to be PF_EXITING,
> __oom_kill_task() is called to elevate the task's timeslice and give it
> access to memory reserves so that it may quickly exit.
>
> This privilege is unnecessary, however, if the task has already detached
> its mm.  Although its possible for the mm to become detached later since
> task_lock() is not held, __oom_kill_task() will simply be a no-op in such
> circumstances.
>
> Subsequently, it is no longer necessary to warn about killing mm-less
> tasks since it is a no-op.
>
> Cc: Rik van Riel <riel@redhat.com>
> Signed-off-by: David Rientjes <rientjes@google.com>

Seems like a good change to make. Did you encounter this situation on
a real machine?

Balbir