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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 68F3EC433DF for ; Tue, 2 Jun 2020 11:29:58 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A6DD720679 for ; Tue, 2 Jun 2020 11:29:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A6DD720679 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id DCC7128000E; Tue, 2 Jun 2020 07:29:56 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D7CEA8E0006; Tue, 2 Jun 2020 07:29:56 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C918928000E; Tue, 2 Jun 2020 07:29:56 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0187.hostedemail.com [216.40.44.187]) by kanga.kvack.org (Postfix) with ESMTP id B29218E0006 for ; Tue, 2 Jun 2020 07:29:56 -0400 (EDT) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 6B4688248047 for ; Tue, 2 Jun 2020 11:29:56 +0000 (UTC) X-FDA: 76884052392.29.dirt56_3986cc2132d37 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin29.hostedemail.com (Postfix) with ESMTP id 4519F18086E45 for ; Tue, 2 Jun 2020 11:29:56 +0000 (UTC) X-HE-Tag: dirt56_3986cc2132d37 X-Filterd-Recvd-Size: 2365 Received: from out30-45.freemail.mail.aliyun.com (out30-45.freemail.mail.aliyun.com [115.124.30.45]) by imf30.hostedemail.com (Postfix) with ESMTP for ; Tue, 2 Jun 2020 11:29:54 +0000 (UTC) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R241e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e07484;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=9;SR=0;TI=SMTPD_---0U-NArnr_1591097390; Received: from IT-FVFX43SYHV2H.local(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0U-NArnr_1591097390) by smtp.aliyun-inc.com(127.0.0.1); Tue, 02 Jun 2020 19:29:51 +0800 Subject: Re: [PATCH] mm/compaction: avoid VM_BUG_ON(PageSlab()) in page_mapcount() To: Hugh Dickins , Andrew Morton Cc: Konstantin Khlebnikov , Vlastimil Babka , David Rientjes , "Kirill A. Shutemov" , Johannes Weiner , linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <158937872515.474360.5066096871639561424.stgit@buzz> From: Alex Shi Message-ID: <7a02e2f6-6fa8-3727-1718-887c0d1dc1cb@linux.alibaba.com> Date: Tue, 2 Jun 2020 19:28:30 +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=gbk X-Rspamd-Queue-Id: 4519F18086E45 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam02 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.009024, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: =D4=DA 2020/6/2 =CF=C2=CE=E712:05, Hugh Dickins =D0=B4=B5=C0: > Cc'ing Alex Shi, because I noticed this when trying his v11 per-memcg > lru_lock series (which appears to be a big improvement over earlier > versions, thanks in particular to Johannes's memcg swap simplifications= ); > and Alex's 12/16 makes a change on top of Konstantin's latter check, > which will now just be reverted. I'm not yet confident in Alex's > isolate_migratepages_block(), in part because this muddle. Hi Hugh, Yes, this could make a very tricky change on compaction behavior. I will = update the patchset after next update. Thanks a lot for notice this! And looking forward to more comments on per= memcg lru_lock patchset! :) Thanks Alex