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Date:   Thu, 5 Apr 2018 18:55:51 +0300
From:   "Kirill A. Shutemov" <kirill@shutemov.name>
To:     Michal Hocko <mhocko@kernel.org>
Cc:     Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v1] mm: consider non-anonymous thp as unmovable page
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On Thu, Apr 05, 2018 at 05:05:47PM +0200, Michal Hocko wrote:
> On Thu 05-04-18 16:40:45, Kirill A. Shutemov wrote:
> > On Thu, Apr 05, 2018 at 02:48:30PM +0200, Michal Hocko wrote:
> [...]
> > > RIght, I confused the two. What is the proper layer to fix that then?
> > > rmap_walk_file?
> > 
> > Maybe something like this? Totally untested.
> 
> This looks way too complex. Why cannot we simply split THP page cache
> during migration?

This way we unify the codepath for archictures that don't support THP
migration and shmem THP.

-- 
 Kirill A. Shutemov