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Date: Thu, 1 Sep 2011 16:28:08 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Andrea Arcangeli <aarcange@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>, Michel Lespinasse <walken@google.com>,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
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        Shaohua Li <shaohua.li@intel.com>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Andi Kleen <andi@firstfloor.org>
Subject: Re: [PATCH] thp: tail page refcounting fix #5
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On Thu, 1 Sep 2011 17:24:17 +0200
Andrea Arcangeli <aarcange@redhat.com> wrote:

> Ideally direct-io should stop calling get_page() on pages
> returned by get_user_pages().

Yeah.  get_user_pages() is sufficient.  Ideally we should be able to
undo the get_user_pages() get_page() from within the IO completion
interrupt and we're done.

Cc Andi, who is our resident dio tweaker ;)