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Shutemov" To: Alex Shi Cc: Matthew Wilcox , Johannes Weiner , Linux-MM , "linux-kernel@vger.kernel.org" , Hugh Dickins Subject: Re: a question of split_huge_page Message-ID: <20200710103318.bm2gp743lagiajao@box> References: <20200709155002.GF12769@casper.infradead.org> <20200709160750.utl46xvavceuvnom@box> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 10, 2020 at 12:51:58PM +0800, Alex Shi wrote: > > > 在 2020/7/10 上午12:07, Kirill A. Shutemov 写道: > > Right, and it's never got removed from LRU during the split. The tail > > pages have to be added to LRU because they now separate from the tail > > page. > > > According to the explaination, looks like we could remove the code path, > since it's never got into. (base on my v15 patchset). Any comments? Yes. But why? It's reasonable failsafe that gives chance to recover if something goes wrong. -- Kirill A. Shutemov