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Date:   Wed, 13 Sep 2023 09:24:12 -0400
From:   Johannes Weiner <hannes@cmpxchg.org>
To:     Vlastimil Babka <vbabka@suse.cz>
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
Subject: Re: [PATCH 1/6] mm: page_alloc: remove pcppage migratetype caching
Message-ID: <20230913132412.GA45543@cmpxchg.org>
References: <20230911195023.247694-1-hannes@cmpxchg.org>
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 <a389d846-c19a-42d3-6206-0a1c80e40b37@suse.cz>
 <20230912145028.GA3228@cmpxchg.org>
 <320c16a7-96b7-65ec-3d80-2eace0ddb290@suse.cz>
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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?

> > 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.