Received: by 2002:a25:683:0:0:0:0:0 with SMTP id 125csp1219437ybg; Tue, 2 Jun 2020 04:32:22 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzU+vJipnONqogwX/Z+o0EYLy0Eb7kd/IMgkivQZ6D1OyKghKLll7tzuo1qrCLsyd1+2A1u X-Received: by 2002:a05:6402:690:: with SMTP id f16mr27235813edy.9.1591097542669; Tue, 02 Jun 2020 04:32:22 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1591097542; cv=none; d=google.com; s=arc-20160816; b=lqZ+xORXBX+Klgt+rDxt+9w0nQPUsDaYJf7x8ayzPi36YphptSq1LjB3NiYHrRi80U Co8eMzh6gcHImR3TDFHKXvWknKiSalS6Yt/fuPi13NlWqbJOkmOVnNpRvKoPJWyk5fcs iv3oQZz7lnKgDbdBqkC+AZKJWfElGfW03R43DECC2Lh5uKYRWidPBxfYuvJRNxfTdydq xn1oNp3Q+97dM+lkncqkOiTt9V8DMD6mXWKEKkjLFVY33VgxWQhdrvvXgcJ/GWbCjPtZ N8r2j/XbXCGuf0DgMxDkbiaq0l0BoiUwAfkhCUmvBgK32LfXtwIc6/B+E8ztPb5sZBXx 0iSA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:in-reply-to :mime-version:user-agent:date:message-id:from:references:cc:to :subject; bh=7KlnKxs679X/xLihVj6gI2e/5Z1x9d7H6s6+IjMJ8Bw=; b=jCwqxdLiYfHuf7w1hOUXUAtoMxUmsKJNeli8WyASX0T8Fwj00o7YPBo/E5K9MxpGLD JoT9MGIIK9uUkbrS5ofM8mN8znN9ZtRLaMQaEqUXiYDPRt+cVYWqk9dK5i2ffqtMyM7e TNIVMjLWc17+xj21oeX57ih+pfZIm06fyIh88UfRzvbl3zZ9L6ccliGHC89D09OJMFQV CqyVdZ/qGJuaIoQ57dAYEGI7iUhKWmOoWfUeiMsjCLGUDud0mCz11V8xfk8iLbNdzMHj H9TUedBH/v46BC3eBmT77ehoYqBIjqcPlCxO1y3xTzvSOe/wfHF1jBZ5Zey/1FoM1Xvo YXoA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=alibaba.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id r8si1371058edi.84.2020.06.02.04.31.58; Tue, 02 Jun 2020 04:32:22 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=alibaba.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726073AbgFBL35 (ORCPT + 99 others); Tue, 2 Jun 2020 07:29:57 -0400 Received: from out30-54.freemail.mail.aliyun.com ([115.124.30.54]:49569 "EHLO out30-54.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725919AbgFBL35 (ORCPT ); Tue, 2 Jun 2020 07:29:57 -0400 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 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ?? 2020/6/2 ????12:05, Hugh Dickins ะด??: > 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