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Date:   Wed, 20 Oct 2021 15:07:49 -0700
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Subject: Re: [PATCH v2] mm: Optimise put_pages_list()
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To:     Matthew Wilcox <willy@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>
Cc:     Mel Gorman <mgorman@techsingularity.net>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
References: <20211007192138.561673-1-willy@infradead.org>
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 <20211007163554.d9088a65f0e293e2bd906a56@linux-foundation.org>
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From:   Anthony Yznaga <anthony.yznaga@oracle.com>
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On 10/8/21 7:17 AM, Matthew Wilcox wrote:
> On Thu, Oct 07, 2021 at 04:35:54PM -0700, Andrew Morton wrote:
>> On Thu, 7 Oct 2021 21:55:21 +0100 Matthew Wilcox <willy@infradead.org> wrote:
>>> My first response is an appeal to authority -- release_pages() does
>>> this same thing.  Only it takes an array, constructs a list and passes
>>> that to put_unref_page_list().  So if that's slower (and lists _are_
>>> slower than arrays), we should have a put_unref_page_array().
>> And put_unref_page_list() does two passes across the list!
>>
>> <quietly sobs>
>>
>> Here is my beautiful release_pages(), as disrtibuted in linux-2.5.33:
> I think that looks much better!
>
>> I guess the current version is some commentary on the aging process?
> I blame the guy who sent cc59850ef940 to Linus back in 2011 ...
>
> I think Anthony was going to look into this and perhaps revert us to
> a pagevec_free() interface.


Sorry for not responding sooner.  I have some cycles so I'll take a look 
at this now.


Anthony