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=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,UNPARSEABLE_RELAY,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 67F49C433DF for ; Thu, 13 Aug 2020 07:45:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3C45620716 for ; Thu, 13 Aug 2020 07:45:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726533AbgHMHpp (ORCPT ); Thu, 13 Aug 2020 03:45:45 -0400 Received: from out30-42.freemail.mail.aliyun.com ([115.124.30.42]:60653 "EHLO out30-42.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726107AbgHMHpm (ORCPT ); Thu, 13 Aug 2020 03:45:42 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R111e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04394;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=19;SR=0;TI=SMTPD_---0U5dIbAA_1597304727; Received: from IT-FVFX43SYHV2H.local(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0U5dIbAA_1597304727) by smtp.aliyun-inc.com(127.0.0.1); Thu, 13 Aug 2020 15:45:29 +0800 Subject: Re: [RFC PATCH 1/3] mm: Drop locked from isolate_migratepages_block To: Alexander Duyck Cc: yang.shi@linux.alibaba.com, lkp@intel.com, rong.a.chen@intel.com, khlebnikov@yandex-team.ru, kirill@shutemov.name, hughd@google.com, linux-kernel@vger.kernel.org, daniel.m.jordan@oracle.com, linux-mm@kvack.org, shakeelb@google.com, willy@infradead.org, hannes@cmpxchg.org, tj@kernel.org, cgroups@vger.kernel.org, akpm@linux-foundation.org, richard.weiyang@gmail.com, mgorman@techsingularity.net, iamjoonsoo.kim@lge.com References: <20200813035100.13054.25671.stgit@localhost.localdomain> <20200813040224.13054.96724.stgit@localhost.localdomain> From: Alex Shi Message-ID: <4403f572-03c3-3061-6fc4-f56e3b6d7b67@linux.alibaba.com> Date: Thu, 13 Aug 2020 15:44:51 +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: <20200813040224.13054.96724.stgit@localhost.localdomain> 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 2020/8/13 下午12:02, Alexander Duyck 写道: > - rcu_read_lock(); > - lruvec = mem_cgroup_page_lruvec(page, pgdat); > - > /* If we already hold the lock, we can skip some rechecking */ > - if (lruvec != locked) { > - if (locked) > - unlock_page_lruvec_irqrestore(locked, flags); > + if (!lruvec || !lruvec_holds_page_lru_lock(page, lruvec)) { Ops, lruvec_holds_page_lru_lock need rcu_read_lock. > + if (lruvec) > + unlock_page_lruvec_irqrestore(lruvec, flags); > > + lruvec = mem_cgroup_page_lruvec(page, pgdat); > compact_lock_irqsave(&lruvec->lru_lock, &flags, cc); > - locked = lruvec; > rcu_read_unlock(); > and some bugs: [ 534.564741] CPU: 23 PID: 545 Comm: kcompactd1 Kdump: loaded Tainted: G S W 5.8.0-next-20200803-00028-g9a7ff2cd6e5c #85 [ 534.577320] Hardware name: Alibaba Alibaba Cloud ECS/Alibaba Cloud ECS, BIOS 1.0.PL.IP.P.027.02 05/29/2020 [ 534.587693] Call Trace: [ 534.590522] dump_stack+0x96/0xd0 [ 534.594231] ___might_sleep.cold.90+0xff/0x115 [ 534.599102] kcompactd+0x24b/0x370 [ 534.602904] ? finish_wait+0x80/0x80 [ 534.606897] ? kcompactd_do_work+0x3d0/0x3d0 [ 534.611566] kthread+0x14e/0x170 [ 534.615182] ? kthread_park+0x80/0x80 [ 534.619252] ret_from_fork+0x1f/0x30 [ 535.629483] BUG: sleeping function called from invalid context at include/linux/freezer.h:57 [ 535.638691] in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 545, name: kcompactd1 [ 535.647601] INFO: lockdep is turned off. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Shi Subject: Re: [RFC PATCH 1/3] mm: Drop locked from isolate_migratepages_block Date: Thu, 13 Aug 2020 15:44:51 +0800 Message-ID: <4403f572-03c3-3061-6fc4-f56e3b6d7b67@linux.alibaba.com> References: <20200813035100.13054.25671.stgit@localhost.localdomain> <20200813040224.13054.96724.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20200813040224.13054.96724.stgit-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="utf-8" To: Alexander Duyck Cc: yang.shi-KPsoFbNs7GizrGE5bRqYAgC/G2K4zDHf@public.gmane.org, lkp-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, rong.a.chen-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, khlebnikov-XoJtRXgx1JseBXzfvpsJ4g@public.gmane.org, kirill-oKw7cIdHH8eLwutG50LtGA@public.gmane.org, hughd-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, daniel.m.jordan-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, shakeelb-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, willy-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org, tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, richard.weiyang-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, mgorman-3eNAlZScCAx27rWaFMvyedHuzzzSOjJt@public.gmane.org, iamjoonsoo.kim-Hm3cg6mZ9cc@public.gmane.org 在 2020/8/13 下午12:02, Alexander Duyck 写道: > - rcu_read_lock(); > - lruvec = mem_cgroup_page_lruvec(page, pgdat); > - > /* If we already hold the lock, we can skip some rechecking */ > - if (lruvec != locked) { > - if (locked) > - unlock_page_lruvec_irqrestore(locked, flags); > + if (!lruvec || !lruvec_holds_page_lru_lock(page, lruvec)) { Ops, lruvec_holds_page_lru_lock need rcu_read_lock. > + if (lruvec) > + unlock_page_lruvec_irqrestore(lruvec, flags); > > + lruvec = mem_cgroup_page_lruvec(page, pgdat); > compact_lock_irqsave(&lruvec->lru_lock, &flags, cc); > - locked = lruvec; > rcu_read_unlock(); > and some bugs: [ 534.564741] CPU: 23 PID: 545 Comm: kcompactd1 Kdump: loaded Tainted: G S W 5.8.0-next-20200803-00028-g9a7ff2cd6e5c #85 [ 534.577320] Hardware name: Alibaba Alibaba Cloud ECS/Alibaba Cloud ECS, BIOS 1.0.PL.IP.P.027.02 05/29/2020 [ 534.587693] Call Trace: [ 534.590522] dump_stack+0x96/0xd0 [ 534.594231] ___might_sleep.cold.90+0xff/0x115 [ 534.599102] kcompactd+0x24b/0x370 [ 534.602904] ? finish_wait+0x80/0x80 [ 534.606897] ? kcompactd_do_work+0x3d0/0x3d0 [ 534.611566] kthread+0x14e/0x170 [ 534.615182] ? kthread_park+0x80/0x80 [ 534.619252] ret_from_fork+0x1f/0x30 [ 535.629483] BUG: sleeping function called from invalid context at include/linux/freezer.h:57 [ 535.638691] in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 545, name: kcompactd1 [ 535.647601] INFO: lockdep is turned off.