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=-4.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 D0631C433E0 for ; Tue, 26 May 2020 20:15:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9F293208B8 for ; Tue, 26 May 2020 20:15:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590524159; bh=Pdby3gr/3jgSVdOYxfNGxNR2pYsSdQiVnkueqiY4dvU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=h3mNRxeoJLHqLAaT0EFszsgCh9bHo93vfO6TYctUoYwhsTNgGDR78gXTjQeq+UdhE ue/kyT2KACOHUOqndiXxI7O46L2RNm8TgTUMduZ34OimvwEAYlP7+QqZ5aZFcPKXXw VjiPtytr1DJ9dwFbuY0A57lYAuE0oVpqhx/Kw2RE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390965AbgEZUP7 (ORCPT ); Tue, 26 May 2020 16:15:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44264 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389565AbgEZUP6 (ORCPT ); Tue, 26 May 2020 16:15:58 -0400 Received: from mail-qt1-x841.google.com (mail-qt1-x841.google.com [IPv6:2607:f8b0:4864:20::841]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3C8D3C03E96D; Tue, 26 May 2020 13:15:58 -0700 (PDT) Received: by mail-qt1-x841.google.com with SMTP id x29so4098512qtv.4; Tue, 26 May 2020 13:15:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=OIlePaEo2DB2lWCSsF6hOGAO/zJmXGR+8z88QbPZwuA=; b=vGsBr5wQpHw68zyoZJvgzHNbkgx9psh74mtNJxqpEOgwrQpmej8EZzHAX4XhlgkBAw LMMIEgnCRPb4utbn/CnS0mmTr+9tLCJAcYDlmkThNex0SAFcxXvxSps/IwKCuihbUAKw /YcMZCmkST4MESr2kDzOSDrPgMTVh1fkmousvPmqj4Hy3X3bCPQ3tan68m6KlRjj6Vfw lyXF9bpOir119aygoHP9wIQ4fbD1LqHyTM0finKJh1dqqGmjdDn+ChV2eLSCqAIhqsiL PW+Vqyz2HPxXk9Fl5HlmTArOGH2iJoMyRZoYlGJgHisGrNuaCiLCovFib5xYjl8eju23 E5Vw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=OIlePaEo2DB2lWCSsF6hOGAO/zJmXGR+8z88QbPZwuA=; b=G3Tubp4O6NyRlMp5HODukT/RmnuLxpnnTsxzEpImLqwAD8jTDmnb1NCxfC/yZWRVlx 6SOpey42TZiZ3VHsOqQ1MjFrKL9NuNKQU/lSVMc+6Rasmt6flDJS6ldQEsmIQ8dcocKq WdmhI7tRXSsmIqX94PdcIx71kkXkl7bIxBRze06jC+iwknfyE6nBRl1KW2fCZ7gsjVR1 J0JyQyMdwGgYuvts8VfG4Mx+eo3ujlBDooN7ZcLGr8b1nNM+0K1eUT1djToy6cAFUmWa YZ+t2/IRIVtcjq6T3E3BNNyf7gAS2P/mbDVUpM1QUu3Mjl5kuvHEPabCaLt5k+Nf7pKD BL4g== X-Gm-Message-State: AOAM530MGvst9Tk6MMf/GDbGp+j4x4jI/sq6UnNasBPBo+SjYcOwKNHJ tlTS79jkaE0YirVI3nVLZks= X-Google-Smtp-Source: ABdhPJwFsA+W7dNO8mOZJWz3XFO0b2jYFQzH2q6iPEOBfPshIJIwCkAhbjiGdUBp1YGreDe/vpnRNw== X-Received: by 2002:ac8:260b:: with SMTP id u11mr626092qtu.380.1590524157306; Tue, 26 May 2020 13:15:57 -0700 (PDT) Received: from localhost ([2620:10d:c091:480::1:85c0]) by smtp.gmail.com with ESMTPSA id d7sm518184qkk.26.2020.05.26.13.15.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 26 May 2020 13:15:56 -0700 (PDT) Date: Tue, 26 May 2020 16:15:54 -0400 From: Tejun Heo To: Boris Burkov Cc: Li Zefan , Johannes Weiner , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: Re: [PATCH cgroup/for-5.8] cgroup: add cpu.stat file to root cgroup Message-ID: <20200526201554.GH83516@mtj.thefacebook.com> References: <20200526200800.3969430-1-boris@bur.io> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200526200800.3969430-1-boris@bur.io> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Tue, May 26, 2020 at 01:08:00PM -0700, Boris Burkov wrote: > Currently, the root cgroup does not have a cpu.stat file. Add one which > is consistent with /proc/stat to capture global cpu statistics that > might not fall under cgroup accounting. > > We haven't done this in the past because the data are already presented > in /proc/stat and we didn't want to add overhead from collecting root > cgroup stats when cgroups are configured, but no cgroups have been > created. > > By keeping the data consistent with /proc/stat, I think we avoid the > first problem, while improving the usability of cgroups stats. > We avoid the second problem by computing the contents of cpu.stat from > existing data collected for /proc/stat anyway. > > Signed-off-by: Boris Burkov > Suggested-by: Tejun Heo If there are any objections, please holler. I'll wait a few days and route it through the cgroup tree. Thanks. -- tejun