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Date: Mon, 07 Oct 2013 15:13:05 -0400
From: Rik van Riel <riel@redhat.com>
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To: Mel Gorman <mgorman@suse.de>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
        Ingo Molnar <mingo@kernel.org>, Andrea Arcangeli <aarcange@redhat.com>,
        Johannes Weiner <hannes@cmpxchg.org>, Linux-MM <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 51/63] sched: numa: Prevent parallel updates to group
 stats during placement
References: <1381141781-10992-1-git-send-email-mgorman@suse.de> <1381141781-10992-52-git-send-email-mgorman@suse.de>
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On 10/07/2013 06:29 AM, Mel Gorman wrote:
> Having multiple tasks in a group go through task_numa_placement
> simultaneously can lead to a task picking a wrong node to run on, because
> the group stats may be in the middle of an update. This patch avoids
> parallel updates by holding the numa_group lock during placement
> decisions.
> 
> Signed-off-by: Mel Gorman <mgorman@suse.de>

Reviewed-by: Rik van Riel <riel@redhat.com>

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