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Reply-To: "Hillf Danton" <hillf.zj@alibaba-inc.com>
From: "Hillf Danton" <hillf.zj@alibaba-inc.com>
To: "'Minchan Kim'" <minchan@kernel.org>,
        "'Andrew Morton'" <akpm@linux-foundation.org>
Cc: <kernel-team@lge.com>, <linux-mm@kvack.org>,
        <linux-kernel@vger.kernel.org>,
        "'Johannes Weiner'" <hannes@cmpxchg.org>,
        "'Michal Hocko'" <mhocko@suse.com>, "'Shaohua Li'" <shli@kernel.org>
References: <1488436765-32350-1-git-send-email-minchan@kernel.org> <1488436765-32350-4-git-send-email-minchan@kernel.org>
In-Reply-To: <1488436765-32350-4-git-send-email-minchan@kernel.org>
Subject: Re: [RFC 03/11] mm: remove SWAP_DIRTY in ttu
Date: Thu, 02 Mar 2017 15:34:45 +0800
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On March 02, 2017 2:39 PM Minchan Kim wrote: 
> @@ -1424,7 +1424,8 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
>  			} else if (!PageSwapBacked(page)) {
>  				/* dirty MADV_FREE page */

Nit: enrich the comment please.
>  				set_pte_at(mm, address, pvmw.pte, pteval);
> -				ret = SWAP_DIRTY;
> +				SetPageSwapBacked(page);
> +				ret = SWAP_FAIL;
>  				page_vma_mapped_walk_done(&pvmw);
>  				break;
>  			}