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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 In-Reply-To: X-Rspamd-Queue-Id: DDECB16A4A9 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam05 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Jul 10, 2020 at 12:51:58PM +0800, Alex Shi wrote: >=20 >=20 > =E5=9C=A8 2020/7/10 =E4=B8=8A=E5=8D=8812:07, Kirill A. Shutemov =E5=86=99= =E9=81=93: > > 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. > >=20 > 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. --=20 Kirill A. Shutemov