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Date:   Wed, 13 Sep 2023 15:34:40 +0200
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Subject: Re: [PATCH 1/6] mm: page_alloc: remove pcppage migratetype caching
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To:     Johannes Weiner <hannes@cmpxchg.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Mel Gorman <mgorman@techsingularity.net>,
        Miaohe Lin <linmiaohe@huawei.com>,
        Kefeng Wang <wangkefeng.wang@huawei.com>,
        Zi Yan <ziy@nvidia.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
References: <20230911195023.247694-1-hannes@cmpxchg.org>
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 <a389d846-c19a-42d3-6206-0a1c80e40b37@suse.cz>
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 <320c16a7-96b7-65ec-3d80-2eace0ddb290@suse.cz>
 <20230913132412.GA45543@cmpxchg.org>
From:   Vlastimil Babka <vbabka@suse.cz>
In-Reply-To: <20230913132412.GA45543@cmpxchg.org>
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On 9/13/23 15:24, Johannes Weiner wrote:
> Hello Vlastimil,
> 
> On Wed, Sep 13, 2023 at 11:33:52AM +0200, Vlastimil Babka wrote:
>> On 9/12/23 16:50, Johannes Weiner wrote:
>> > From 429d13322819ab38b3ba2fad6d1495997819ccc2 Mon Sep 17 00:00:00 2001
>> > From: Johannes Weiner <hannes@cmpxchg.org>
>> > Date: Tue, 12 Sep 2023 10:16:10 -0400
>> > Subject: [PATCH] mm: page_alloc: optimize free_unref_page_list()
>> > 
>> > Move direct freeing of isolated pages to the lock-breaking block in
>> > the second loop. This saves an unnecessary migratetype reassessment.
>> > 
>> > Minor comment and local variable scoping cleanups.
>> 
>> Looks like batch_count and locked_zone could be moved to the loop scope as well.
> 
> Hm they both maintain values over multiple iterations, so I don't
> think that's possible. Am I missing something?

True, disregard :D

>> > Suggested-by: Vlastimil Babka <vbabka@suse.cz>
>> > Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
>> 
>> Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
> 
> Thanks! I'll send this out properly with your tag.

np!