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Date: Thu, 16 Mar 2017 13:40:23 +0900
From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Minchan Kim <minchan@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org, kernel-team@lge.com,
        Johannes Weiner <hannes@cmpxchg.org>, Michal Hocko <mhocko@suse.com>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Anshuman Khandual <khandual@linux.vnet.ibm.com>
Subject: Re: [PATCH v2 10/10] mm: remove SWAP_[SUCCESS|AGAIN|FAIL]
Message-ID: <20170316044023.GA2597@jagdpanzerIV.localdomain>
References: <1489555493-14659-1-git-send-email-minchan@kernel.org>
 <1489555493-14659-11-git-send-email-minchan@kernel.org>
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Hello,


On (03/15/17 14:24), Minchan Kim wrote:
> There is no user for it. Remove it.
> 

there is one.

mm/rmap.c

try_to_unmap_one()
...
	if (unlikely(PageSwapBacked(page) != PageSwapCache(page))) {
		WARN_ON_ONCE(1);
		ret = SWAP_FAIL;
		page_vma_mapped_walk_done(&pvmw);
		break;
	}

	-ss