Date:   Wed, 24 Nov 2021 23:12:38 +0300
From:   "Kirill A. Shutemov" <kirill@shutemov.name>
To:     Shakeel Butt <shakeelb@google.com>
Cc:     David Hildenbrand <david@redhat.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Yang Shi <shy828301@gmail.com>, Zi Yan <ziy@nvidia.com>,
        Matthew Wilcox <willy@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] mm: thp: update split_queue_len correctly
Message-ID: <20211124201238.3xzpy2b5zcv7j23s@box.shutemov.name>
References: <20211123190916.1738458-1-shakeelb@google.com>
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On Tue, Nov 23, 2021 at 11:09:16AM -0800, Shakeel Butt wrote:
> The deferred THPs are split on memory pressure through shrinker
> callback and splitting of THP during reclaim can fail for several
> reasons like unable to lock the THP, under writeback or unexpected
> number of pins on the THP. Such pages are put back on the deferred split
> list for consideration later. However kernel does not update the
> deferred queue size on putting back the pages whose split was failed.
> This patch fixes that.

Hm. No. split_huge_page_to_list() updates the queue size on split success.

NAK.

-- 
 Kirill A. Shutemov