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Reply-To: "Hillf Danton" <hillf.zj@alibaba-inc.com>
From: "Hillf Danton" <hillf.zj@alibaba-inc.com>
To: "'Johannes Weiner'" <hannes@cmpxchg.org>,
        "'Andrew Morton'" <akpm@linux-foundation.org>
Cc: "'Jia He'" <hejianet@gmail.com>, "'Michal Hocko'" <mhocko@suse.cz>,
        "'Mel Gorman'" <mgorman@suse.de>, <linux-mm@kvack.org>,
        <linux-kernel@vger.kernel.org>, <kernel-team@fb.com>
References: <20170228214007.5621-1-hannes@cmpxchg.org> <20170228214007.5621-8-hannes@cmpxchg.org>
In-Reply-To: <20170228214007.5621-8-hannes@cmpxchg.org>
Subject: Re: [PATCH 7/9] mm: delete NR_PAGES_SCANNED and pgdat_reclaimable()
Date: Thu, 02 Mar 2017 11:34:34 +0800
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On March 01, 2017 5:40 AM Johannes Weiner wrote: 
> 
> NR_PAGES_SCANNED counts number of pages scanned since the last page
> free event in the allocator. This was used primarily to measure the
> reclaimability of zones and nodes, and determine when reclaim should
> give up on them. In that role, it has been replaced in the preceeding
> patches by a different mechanism.
> 
> Being implemented as an efficient vmstat counter, it was automatically
> exported to userspace as well. It's however unlikely that anyone
> outside the kernel is using this counter in any meaningful way.
> 
> Remove the counter and the unused pgdat_reclaimable().
> 
> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
> ---
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>