Date: Fri, 5 Jan 2018 13:27:48 -0600 (CST)
From: Christopher Lameter <cl@linux.com>
To: Michal Hocko <mhocko@kernel.org>
cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Zi Yan <zi.yan@cs.rutgers.edu>,
        Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
        "Kirill A. Shutemov" <kirill@shutemov.name>,
        Vlastimil Babka <vbabka@suse.cz>,
        Andrea Reale <ar@linux.vnet.ibm.com>, linux-mm@kvack.org,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/3] mm, numa: rework do_pages_move
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On Fri, 5 Jan 2018, Michal Hocko wrote:

> > Also why are you migrating the pages on pagelist if a
> > add_page_for_migration() fails? One could simply update
> > the status in user space and continue.
>
> I am open to further cleanups. Care to send a full patch with the
> changelog? I would rather not fold more changes to the already tested
> one.

While doing that I saw that one could pull the rwsem locking out of
add_page_for_migration() as well in order to avoid taking it for each 4k
page. Include that?