From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Shi Subject: Re: [PATCH v9 02/20] mm/memcg: fold lock_page_lru into commit_charge Date: Wed, 4 Mar 2020 15:19:46 +0800 Message-ID: <4131e7d9-acad-4372-73b1-6fa1b0b251ef@linux.alibaba.com> References: <1583146830-169516-1-git-send-email-alex.shi@linux.alibaba.com> <20200304031335.9784-1-hdanton@sina.com> Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20200304031335.9784-1-hdanton@sina.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="iso-8859-1" To: Hillf Danton Cc: cgroups@vger.kernel.org, akpm@linux-foundation.org, mgorman@techsingularity.net, tj@kernel.org, hughd@google.com, khlebnikov@yandex-team.ru, daniel.m.jordan@oracle.com, yang.shi@linux.alibaba.com, willy@infradead.org, hannes@cmpxchg.org, lkp@intel.com, Michal Hocko , Vladimir Davydov , linux-mm@kvack.org, linux-kernel@vger.kernel.org =D4=DA 2020/3/4 =C9=CF=CE=E711:13, Hillf Danton =D0=B4=B5=C0: >> * Nobody should be changing or seriously looking at >> * page->mem_cgroup at this point: >> @@ -2633,8 +2611,13 @@ static void commit_charge(struct page *page, stru= ct mem_cgroup *memcg, >> */ >> page->mem_cgroup =3D memcg; >> =20 > Well it is likely to update memcg for page without lru_lock held even if > more care is required, which is a change added in the current semantic and > worth a line of words in log. >=20 the lru_lock is guard for lru list, not for page->mem_cgroup, seem no need = to highlight this point. Do we? Thanks Alex