From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.6 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A7A4DC433E1 for ; Thu, 20 Aug 2020 12:08:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8EB1C207BB for ; Thu, 20 Aug 2020 12:08:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729738AbgHTMIn (ORCPT ); Thu, 20 Aug 2020 08:08:43 -0400 Received: from out30-130.freemail.mail.aliyun.com ([115.124.30.130]:36079 "EHLO out30-130.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729885AbgHTJ57 (ORCPT ); Thu, 20 Aug 2020 05:57:59 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R721e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04407;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=19;SR=0;TI=SMTPD_---0U6IpR5A_1597917472; Received: from IT-FVFX43SYHV2H.local(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0U6IpR5A_1597917472) by smtp.aliyun-inc.com(127.0.0.1); Thu, 20 Aug 2020 17:57:54 +0800 Subject: Re: [RFC PATCH v2 5/5] mm: Split move_pages_to_lru into 3 separate passes To: Alexander Duyck Cc: Yang Shi , kbuild test robot , Rong Chen , Konstantin Khlebnikov , "Kirill A. Shutemov" , Hugh Dickins , LKML , Daniel Jordan , linux-mm , Shakeel Butt , Matthew Wilcox , Johannes Weiner , Tejun Heo , cgroups@vger.kernel.org, Andrew Morton , Wei Yang , Mel Gorman , Joonsoo Kim References: <20200819041852.23414.95939.stgit@localhost.localdomain> <20200819042738.23414.60815.stgit@localhost.localdomain> <084c58a7-7aac-820c-9606-19391c35b9b5@linux.alibaba.com> From: Alex Shi Message-ID: <87ded438-e908-117d-ecfb-1af7224d46da@linux.alibaba.com> Date: Thu, 20 Aug 2020 17:56:36 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2020/8/19 下午10:42, Alexander Duyck 写道: >> It's actually changed the meaning from current func. which I had seen a bug if no relock. >> but after move to 5.9 kernel, I can not reprodce the bug any more. I am not sure if 5.9 fixed >> the problem, and we don't need relock here. > So I am not sure what you mean here about "changed the meaning from > the current func". Which function are you referring to and what > changed? > > From what I can tell the pages cannot change memcg because they were > isolated and had the LRU flag stripped. They shouldn't be able to > change destination LRU vector as a result. Assuming that, then they > can all be processed under same LRU lock and we can avoid having to > release it until we are forced to do so to call putback_lru_page or > destroy the compound pages that were freed while we were shrinking the > LRU lists. > I had sent a bug which base on 5.8 kernel. https://lkml.org/lkml/2020/7/28/465 I am not sure it was fixed in new kernel. The original line was introduced by Hugh Dickins I believe it would be great if you can get comments from him. Thanks Alex