Date: Fri, 3 Mar 2017 12:04:16 +0900
From: Minchan Kim <minchan@kernel.org>
To: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, kernel-team@lge.com,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Johannes Weiner <hannes@cmpxchg.org>, Michal Hocko <mhocko@suse.com>
Subject: Re: [RFC 04/11] mm: remove SWAP_MLOCK check for SWAP_SUCCESS in ttu
Message-ID: <20170303030416.GF3503@bbox>
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On Thu, Mar 02, 2017 at 08:21:46PM +0530, Anshuman Khandual wrote:
> On 03/02/2017 12:09 PM, Minchan Kim wrote:
> > If the page is mapped and rescue in ttuo, page_mapcount(page) == 0 cannot
> 
> Nit: "ttuo" is very cryptic. Please expand it.

No problem.

> 
> > be true so page_mapcount check in ttu is enough to return SWAP_SUCCESS.
> > IOW, SWAP_MLOCK check is redundant so remove it.
> 
> Right, page_mapcount(page) should be enough to tell whether swapping
> out happened successfully or the page is still mapped in some page
> table.
> 

Thanks for the review, Anshuman!