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=-14.4 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 E31F9C43461 for ; Mon, 14 Sep 2020 15:37:35 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 65D8020756 for ; Mon, 14 Sep 2020 15:37:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="QqiQ6xW7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 65D8020756 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D9129900007; Mon, 14 Sep 2020 11:37:34 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D400E6B0068; Mon, 14 Sep 2020 11:37:34 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C574D900007; Mon, 14 Sep 2020 11:37:34 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0194.hostedemail.com [216.40.44.194]) by kanga.kvack.org (Postfix) with ESMTP id AEF4E6B0062 for ; Mon, 14 Sep 2020 11:37:34 -0400 (EDT) Received: from smtpin30.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 61BA04DAD for ; Mon, 14 Sep 2020 15:37:34 +0000 (UTC) X-FDA: 77262071628.30.pet97_3a1446027109 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin30.hostedemail.com (Postfix) with ESMTP id 1ACBB180B3C83 for ; Mon, 14 Sep 2020 15:37:34 +0000 (UTC) X-HE-Tag: pet97_3a1446027109 X-Filterd-Recvd-Size: 3693 Received: from mail-lj1-f193.google.com (mail-lj1-f193.google.com [209.85.208.193]) by imf17.hostedemail.com (Postfix) with ESMTP for ; Mon, 14 Sep 2020 15:37:33 +0000 (UTC) Received: by mail-lj1-f193.google.com with SMTP id v23so94137ljd.1 for ; Mon, 14 Sep 2020 08:37:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=K4ao+npZ6MxTlYLJj73SuM3MYmDgRwOTBj2VBQ+8aQw=; b=QqiQ6xW7AdhcYi1OC2qsAevLzikaA4B2B2HmiF8E4JiJ3lndiY2zyjlmfQdljBEpsu wnzt39W7OkhG6hVVv0LU6qArb8GcclfoatunyFpVXrFjrN8WwKHyFrturfPeDR1N4uIg O7WvUBHhSaBagCz8j4SJtlrL++cp0DKMDP76VZxD69TxZFiq7XP246R/5nGrcvgM9z+M sr+Gh5le/CKY1RrlTeDP9/dVwTXsyll0buo08vjzthzY6ziEoCxtDPi6G88Ipvigmuu/ ViTE32WfPr4r5OnN1bimsysiOcMNByATfPHjxJ+eTRjx5Si0EMvHdcuOTIFexSCUI8gv 47hw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=K4ao+npZ6MxTlYLJj73SuM3MYmDgRwOTBj2VBQ+8aQw=; b=UU3JIJy+8d+jYelOENVipCQn5n085N9m4XNrbjKDN0WuBUmTeHxqD6j5avBnOV1vOL ADuk7ggF5fvB1rqEPNP6tLyTnonBAxf63+2OJvrZg3uUYxzDGpnF3zVJrp5VhDLbabib oNnO+ZmQSFqHSxHnKJzQSvhNTXpTUd9c3ViR35Em4Vyh1G+ww1GUoqZKobMmCXDT5sSE DLaEfYLGnn6TvOWZNktNwCshPjkiIrEJpuUIeX+3MtNYKwzeZkZh6Mn829JFTr4wogNU n+jVv6HPMRlGO/ti2Ps60RCOw5dfN1b5xtXUG7dAiWBugRXbqFCCLX57GZ/1+9m+FJQx rBww== X-Gm-Message-State: AOAM533/6Xwy4r29iV8ZFlByVc3vGCKoS9ytKuwTKGvRo60QHkfD2iHa b3RnZa1Vp/MR2DZtUFlIcySmdrLDBAH1rbfTSVPs5Q== X-Google-Smtp-Source: ABdhPJwS8YHP1iUcafEkzqm6r7X9c+DloJI9X6GeP5Nto1Ho7LBEnwm4bfjuMB3M1DwukxWL2rUryFlBIf8BFedMO3E= X-Received: by 2002:a2e:b4f5:: with SMTP id s21mr5532851ljm.270.1600097852018; Mon, 14 Sep 2020 08:37:32 -0700 (PDT) MIME-Version: 1.0 References: <20200914024452.19167-1-longman@redhat.com> <20200914024452.19167-4-longman@redhat.com> In-Reply-To: <20200914024452.19167-4-longman@redhat.com> From: Shakeel Butt Date: Mon, 14 Sep 2020 08:37:21 -0700 Message-ID: Subject: Re: [PATCH v2 3/3] mm/memcg: Unify swap and memsw page counters To: Waiman Long Cc: Johannes Weiner , Michal Hocko , Vladimir Davydov , Andrew Morton , Tejun Heo , LKML , Cgroups , Linux MM , Chris Down , Roman Gushchin , Yafang Shao Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 1ACBB180B3C83 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 X-Bogosity: Ham, tests=bogofilter, spamicity=0.001863, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sun, Sep 13, 2020 at 7:45 PM Waiman Long wrote: > > The swap page counter is v2 only while memsw is v1 only. As v1 and v2 > controllers cannot be active at the same time, there is no point to keep > both swap and memsw page counters in mem_cgroup. The previous patch has > made sure that memsw page counter is updated and accessed only when in > v1 code paths. So it is now safe to alias the v1 memsw page counter to v2 > swap page counter. This saves 14 long's in the size of mem_cgroup. This > is a saving of 112 bytes for 64-bit archs. > > While at it, also document which page counters are used in v1 and/or v2. > > Signed-off-by: Waiman Long Reviewed-by: Shakeel Butt