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=-1.0 required=3.0 tests=MAILING_LIST_MULTI, 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 82D4FC433E0 for ; Fri, 15 May 2020 09:04:45 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2BF85206B6 for ; Fri, 15 May 2020 09:04:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2BF85206B6 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 90B4A90000C; Fri, 15 May 2020 05:04:44 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8BC248E0005; Fri, 15 May 2020 05:04:44 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7AA6F90000C; Fri, 15 May 2020 05:04:44 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0177.hostedemail.com [216.40.44.177]) by kanga.kvack.org (Postfix) with ESMTP id 62CBE8E0005 for ; Fri, 15 May 2020 05:04:44 -0400 (EDT) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 2527E442A for ; Fri, 15 May 2020 09:04:44 +0000 (UTC) X-FDA: 76818368088.24.shock48_466b0139b380e X-HE-Tag: shock48_466b0139b380e X-Filterd-Recvd-Size: 3570 Received: from mail-wr1-f66.google.com (mail-wr1-f66.google.com [209.85.221.66]) by imf44.hostedemail.com (Postfix) with ESMTP for ; Fri, 15 May 2020 09:04:43 +0000 (UTC) Received: by mail-wr1-f66.google.com with SMTP id v12so2556956wrp.12 for ; Fri, 15 May 2020 02:04:43 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=9QDVZDXZoqSloGv08GEy2MAxiYOaCzJPvgAYS9OutzI=; b=kEsT6cSt19/sDvSIPuYrm6FnmIt05V7xlow0aBXrrid1C3chg26XJRC9+vOpiDs1xP ce6Tjg1oNl/se/WVPcVKKA8kro/+DDhJBeUl/Es0oohgl2YeUGpFwzd1tfdgPwQAbDji gB0yc2aX9wbYHcjjtnN2pPfDdJ6EVw1zfWj5YkhkLFYQvi0uEcisDW05NxiOjHTS6kLg tKyYcSkuVJVzJ+jwbRgqSSc8o5jNww1iZswbgBSDPkHBWmZuaUVD3qMtVLtCqWrkeG97 ZIzZa0lokxSisTT2TywPBZEh2aUT1YPYDswqarPz/MCQvusWeVO4oheV7JQquUD+UiIj +4UQ== X-Gm-Message-State: AOAM531HzqPRTibcUD39lbGMpp2c9PZoMD6HZUxlMa2/y36+lkNQlQ6B SdvHC8KGHZQBzs0TZ20fiqw= X-Google-Smtp-Source: ABdhPJy6OuUYUgPiVAlIah3CMGMVQCvfBn1TKTEVWtRuHvhUaoWQqy0w+nQkgDhq3DgMc1Ml/o1Vjg== X-Received: by 2002:a5d:530c:: with SMTP id e12mr3313165wrv.271.1589533482726; Fri, 15 May 2020 02:04:42 -0700 (PDT) Received: from localhost (ip-37-188-249-36.eurotel.cz. [37.188.249.36]) by smtp.gmail.com with ESMTPSA id m3sm2547773wrn.96.2020.05.15.02.04.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 15 May 2020 02:04:41 -0700 (PDT) Date: Fri, 15 May 2020 11:04:40 +0200 From: Michal Hocko To: Feng Tang Cc: Andrew Morton , Johannes Weiner , Matthew Wilcox , Mel Gorman , Kees Cook , Luis Chamberlain , Iurii Zaikin , "Kleen, Andi" , "Chen, Tim C" , "Hansen, Dave" , "Huang, Ying" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 2/3] mm/util.c: make vm_memory_committed() more accurate Message-ID: <20200515090440.GN29153@dhcp22.suse.cz> References: <1588922717-63697-1-git-send-email-feng.tang@intel.com> <1588922717-63697-3-git-send-email-feng.tang@intel.com> <20200515072307.GG29153@dhcp22.suse.cz> <20200515081109.GD69177@shbuild999.sh.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200515081109.GD69177@shbuild999.sh.intel.com> 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 Fri 15-05-20 16:11:09, Feng Tang wrote: > On Fri, May 15, 2020 at 03:23:07PM +0800, Michal Hocko wrote: > > On Fri 08-05-20 15:25:16, Feng Tang wrote: > > > percpu_counter_sum_positive() will provide more accurate info. > > > > Why do we need that? > > This is a preparation for patch 3/3, which will enlarge the batch size > of percpu-counter 'vm_committed_as'. Andi Kleen concerned that may > hurt the accuracy for those readers (currently only /proc/meminfo > and hyperV balloon drivers for status check) > > As in worst case, the deviation could be 'batch * nr_cpus', and > with patch 3/3, that could be totalram_pages/16. This information belongs to the changelog. -- Michal Hocko SUSE Labs