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=-18.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_IN_DEF_DKIM_WL autolearn=ham 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 D6AC5C433E0 for ; Fri, 19 Mar 2021 01:22:56 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5F14564E01 for ; Fri, 19 Mar 2021 01:22:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5F14564E01 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 CF4026B006E; Thu, 18 Mar 2021 21:22:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CA4F56B0071; Thu, 18 Mar 2021 21:22:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B6DA46B0072; Thu, 18 Mar 2021 21:22:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0212.hostedemail.com [216.40.44.212]) by kanga.kvack.org (Postfix) with ESMTP id 9DF7F6B006E for ; Thu, 18 Mar 2021 21:22:55 -0400 (EDT) Received: from smtpin36.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 642358249980 for ; Fri, 19 Mar 2021 01:22:55 +0000 (UTC) X-FDA: 77934874710.36.634D24D Received: from mail-lf1-f49.google.com (mail-lf1-f49.google.com [209.85.167.49]) by imf03.hostedemail.com (Postfix) with ESMTP id 1862CC0007CA for ; Fri, 19 Mar 2021 01:22:51 +0000 (UTC) Received: by mail-lf1-f49.google.com with SMTP id q29so7473853lfb.4 for ; Thu, 18 Mar 2021 18:22:51 -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=CW4McI8JkV+pieEAOjNv+vlbnY5aNnNxkeeFzG0tW8w=; b=cDeKZHVFxabXMfipkJOP7Ibt7u7HVzssV//KJmna76gp11QpclpUxew/DscSIAVeT/ ILTnAIjHt4zXkV5rdRyMkftIzQhnm6/f4Fc1g/eFn3KcKwKdUaLvvXlCK9S6uSyQMJuy z8rnpEi1ijjr2S0a5dAwX48+eC9eYYzuuKyUyW8TWRdIdYlNVAScpyqUbBB+tzRz0DXp fwYpz0a0GpiFPVbBulejetQGfE9enAm6Qp3Az8rG1NCuJX/H5eajWjAZ3zEYkgbu4dGW 9z/ugj21ayFY1WgcWWhE9uw/ZP7lLMCb5UU9bvxnwru5IsOfv/1HtFzPEOaDcXXy7cUf fuhw== 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=CW4McI8JkV+pieEAOjNv+vlbnY5aNnNxkeeFzG0tW8w=; b=fMRWOyddStnhMMiGxVRKKhMWM2BO49KSmxojWjHxK66PKChxq13yA8BO26AXo9C6J/ /uNBN48obDI314+ITftVRbPRqTNh8pcHM7n/iE5Ya2ixP9c8XYxV40gQF5yeIo40NOBn aCPOJ/t9N3EzgakMRsiy7OgxCcJhNT4SzP95C9c9QVSnvC/TS/fNOB3PZ8k2ndOeuKqT 6x5BBEVpkTYGLMD18nQPNb+FIt8UQOhlf5DUF1zEXlKEcoLGhRHK1JF0vmqAwSAudsSc scTCyHakPYx9BywHtLlCLCAq2E3jNDSEqyWm4L6HUrwnk+PvZh3XvmJD/2wuxWm4dFdc M2Hg== X-Gm-Message-State: AOAM530ls++yJykbKpWfORIMjTbUAlqD2rHDYoun5QlzFkFuPgJih0Lr tWwvk33Q1yvakUMg3o/tgIcwoe7z3E73dfql1dhMZQ== X-Google-Smtp-Source: ABdhPJyeKUzfk7qJwdmTpIOVyFefL4jP2HUWSjTzyZpGRUmli8dFZV88KSSE8oBfMULFwo4SPWZ4Um/djOyrGlRodTE= X-Received: by 2002:a19:ee19:: with SMTP id g25mr6696142lfb.83.1616116970201; Thu, 18 Mar 2021 18:22:50 -0700 (PDT) MIME-Version: 1.0 References: <20210318110658.60892-1-songmuchun@bytedance.com> <20210318110658.60892-4-songmuchun@bytedance.com> In-Reply-To: <20210318110658.60892-4-songmuchun@bytedance.com> From: Shakeel Butt Date: Thu, 18 Mar 2021 18:22:39 -0700 Message-ID: Subject: Re: [PATCH v4 3/5] mm: memcontrol: change ug->dummy_page only if memcg changed To: Muchun Song Cc: Roman Gushchin , Johannes Weiner , Michal Hocko , Andrew Morton , Vladimir Davydov , LKML , Linux MM , Xiongchun duan Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 1862CC0007CA X-Stat-Signature: cs4qud35zemp9bgcawyi7frek1rmpzmm Received-SPF: none (google.com>: No applicable sender policy available) receiver=imf03; identity=mailfrom; envelope-from=""; helo=mail-lf1-f49.google.com; client-ip=209.85.167.49 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616116971-493192 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Mar 18, 2021 at 4:08 AM Muchun Song wrote: > > Just like assignment to ug->memcg, we only need to update ug->dummy_page > if memcg changed. So move it to there. This is a very small optimization. > > Signed-off-by: Muchun Song Reviewed-by: Shakeel Butt