From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wei Yang Subject: Re: [Patch v2] mm: thp: grab the lock before manipulation defer list Date: Mon, 13 Jan 2020 16:23:08 +0800 Message-ID: <20200113082308.GB27972@richard> References: <20200109143054.13203-1-richardw.yang@linux.intel.com> <20200111000352.efy6krudecpshezh@box> <20200112022858.GA17733@richard> <20200112225718.5vqzezfclacujyx3@box> <20200113004457.GA27762@richard> <20200113073614.jo2txcmazwlesl7b@box.shutemov.name> Reply-To: Wei Yang Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: <20200113073614.jo2txcmazwlesl7b@box.shutemov.name> Sender: linux-kernel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: "Kirill A. Shutemov" Cc: Wei Yang , hannes@cmpxchg.org, mhocko@kernel.org, vdavydov.dev@gmail.com, akpm@linux-foundation.org, cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kirill.shutemov@linux.intel.com, yang.shi@linux.alibaba.com, alexander.duyck@gmail.com, rientjes@google.com On Mon, Jan 13, 2020 at 10:36:14AM +0300, Kirill A. Shutemov wrote: >On Mon, Jan 13, 2020 at 08:44:57AM +0800, Wei Yang wrote: >> >> It is possible two page in the same pgdate or memcg grab page lock >> >> respectively and then access the same defer queue concurrently. >> >> If my understanding is correct, you agree with my statement? > >Which one? If the one above then no. list_empty only accesses list_head >for the struct page, not the queue. > Ah, I get your point. >-- > Kirill A. Shutemov -- Wei Yang Help you, Help me