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=-3.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS 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 2027AC55178 for ; Sat, 7 Nov 2020 01:30:20 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5A17120728 for ; Sat, 7 Nov 2020 01:30:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="jZrN5F7/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5A17120728 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 7B6446B0036; Fri, 6 Nov 2020 20:30:18 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 766236B005D; Fri, 6 Nov 2020 20:30:18 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6550C6B0068; Fri, 6 Nov 2020 20:30:18 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0166.hostedemail.com [216.40.44.166]) by kanga.kvack.org (Postfix) with ESMTP id 3ADBD6B0036 for ; Fri, 6 Nov 2020 20:30:18 -0500 (EST) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id D559B181AEF00 for ; Sat, 7 Nov 2020 01:30:17 +0000 (UTC) X-FDA: 77455891674.07.bite89_030892f272d7 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin07.hostedemail.com (Postfix) with ESMTP id BDDB21803F9AC for ; Sat, 7 Nov 2020 01:30:17 +0000 (UTC) X-HE-Tag: bite89_030892f272d7 X-Filterd-Recvd-Size: 3201 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf23.hostedemail.com (Postfix) with ESMTP for ; Sat, 7 Nov 2020 01:30:16 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1E9F320720; Sat, 7 Nov 2020 01:30:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604712615; bh=5ja+hHDhLaw834klWxEIsEobJjKzEYlU1fK3r77mU5g=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=jZrN5F7/+Zu3GmPA5iLrAhldT/HnmmgsyZF2eKJZ9aZUKndfgBlXBzDVBKRlKB20J gnoQgoeBoM9JlKv5BRD526px7a20WshtiPv/94Md18VkK2B5uF32W2PcQAXlnjhxJP wyfF6u9yfTq52lPBu14DkQlLqPNi719Z1w4wjAJ4= Date: Fri, 6 Nov 2020 17:30:14 -0800 From: Andrew Morton To: Hui Su Cc: hannes@cmpxchg.org, mhocko@kernel.org, vdavydov.dev@gmail.com, shakeelb@google.com, guro@fb.com, laoar.shao@gmail.com, chris@chrisdown.name, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH] mm/memcontrol:rewrite mem_cgroup_page_lruvec() Message-Id: <20201106173014.e13b5fe5edec41d1f7fdf072@linux-foundation.org> In-Reply-To: <20201104142516.GA106571@rlk> References: <20201104142516.GA106571@rlk> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Bogosity: Ham, tests=bogofilter, spamicity=0.000958, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, 4 Nov 2020 22:25:16 +0800 Hui Su wrote: > mem_cgroup_page_lruvec() in memcontrol.c and > mem_cgroup_lruvec() in memcontrol.h is very similar > except for the param(page and memcg) which also can be > convert to each other. > > So rewrite mem_cgroup_page_lruvec() with mem_cgroup_lruvec(). Alex Shi's "mm/memcg: warning on !memcg after readahead page charged" (https://lkml.kernel.org/r/1604283436-18880-3-git-send-email-alex.shi@linux.alibaba.com) changes mem_cgroup_page_lruvec() thusly: --- a/mm/memcontrol.c~mm-memcg-warning-on-memcg-after-readahead-page-charged +++ a/mm/memcontrol.c @@ -1325,10 +1325,7 @@ struct lruvec *mem_cgroup_page_lruvec(st } memcg = page_memcg(page); - /* - * Swapcache readahead pages are added to the LRU - and - * possibly migrated - before they are charged. - */ + VM_WARN_ON_ONCE_PAGE(!memcg, page); if (!memcg) memcg = root_mem_cgroup; So the patch didn't apply. That's easily fixed, but it does make one wonder whether this: > -struct lruvec *mem_cgroup_page_lruvec(struct page *, struct pglist_data *); > +/** > + * mem_cgroup_page_lruvec - return lruvec for isolating/putting an LRU page > + * @page: the page > + * @pgdat: pgdat of the page > + * > + * This function relies on page->mem_cgroup being stable. > + */ > +static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page, > + struct pglist_data *pgdat) > +{ > + struct mem_cgroup *memcg = page->mem_cgroup; > + > + return mem_cgroup_lruvec(memcg, pgdat); > +} Should be using page_memcg()?