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Date: Mon, 12 May 2014 11:07:12 -0500 (CDT)
From: Christoph Lameter <cl@linux.com>
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To: Jianyu Zhan <nasa4836@gmail.com>
cc: Andrew Morton <akpm@linux-foundation.org>, Hugh Dickins <hughd@google.com>,
        Rik van Riel <riel@redhat.com>, Mel Gorman <mgorman@suse.de>,
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Subject: Re: [PATCH 1/3] mm: add comment for __mod_zone_page_stat
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On Mon, 12 May 2014, Jianyu Zhan wrote:

> This means they guarantee that even they are preemted the vm
> counter won't be modified incorrectly.  Because the counter is page-related
> (e.g., a new anon page added), and they are exclusively hold the pte lock.

Ok. if these locations hold the pte lock then preemption is disabled and
you are ok to use __mod_zone_page_state. Has nothing to do with the page.