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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 854D2C433F5 for ; Tue, 26 Oct 2021 23:58:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6885160FD7 for ; Tue, 26 Oct 2021 23:58:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240369AbhJ0ABB (ORCPT ); Tue, 26 Oct 2021 20:01:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44686 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240362AbhJ0AAu (ORCPT ); Tue, 26 Oct 2021 20:00:50 -0400 Received: from mail-pg1-x531.google.com (mail-pg1-x531.google.com [IPv6:2607:f8b0:4864:20::531]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C451AC061570; Tue, 26 Oct 2021 16:58:25 -0700 (PDT) Received: by mail-pg1-x531.google.com with SMTP id r28so1188802pga.0; Tue, 26 Oct 2021 16:58:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=caC3B6GjKaBRDDR0pkhw6AqjE4SAmcqhSKEygWuTBsQ=; b=pC0e/FlNdelKbXYwhK+ASlyQ5jzvhyztGiS4zvZ3CE59AtXj3P7UhJNSDsDLFS10NW bHNo2VacxvFTNet+iaahlaLRCmOFithcpZmhp2Dyl6/b/8R3PoY36vxl2TtQaTNRXdSg CuFRnhkffVpMd8G9QXkq6neQkMUYe+9BL2ifcdLaRhxes3I3k6lHoJiYtdrkTSNIGHdB wOm86JNvdOCP4sf+lbUiMdF0QWxMcSUi4eCaO9lEI17vbJGK78D7ezdk9pMwhLtYAemi pFGdPxjQATyD5onLIo4orkKVqiTxHkB3v4DXyaASas0vdEWlUf/Jn68mZ/q4/949n5OT Yhpg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=caC3B6GjKaBRDDR0pkhw6AqjE4SAmcqhSKEygWuTBsQ=; b=XLYuGcSN2zEfkRjtSi+9ftIfT1WSY2yd8T26XoFU/Rb0S30aDzo+GqCnOfIO+GlxaK LfIpHl+v9PDo4z4jjk1Ayq9appi5GitjNh6YCrwPJqtF1HGBQP+VYMsjM7d6ee0UajVr TlKMiAAxZPhbDaoDergd2ezu5GCRCMiQ9K9GAH1moDlGQNTmKxoDZA0YntiiEYWoEwky G8fUDk21ewReBKt+59b7fbxBKHXzvHO1X/0mCAw5lNpyUBT3wPcsdL7hfTj1E7xz48ju J9mZ5fEA/6RN6mS9wyi5UY9phup2rzKEEwPhGfWb+X6wC7PQlMBCD7E9AaX00EHOhAWl /5jQ== X-Gm-Message-State: AOAM533VVxCLR6WEPqxrv4axnpE7RTuzeI/wXVX2m3BCfg8Pgx8fFoWg Qj+mDVv24WcL5j/6iiQXHTc= X-Google-Smtp-Source: ABdhPJz7s3bMcUlp/xqca6cQ1XdJyAoXow5AJAoXehe+hgff4ZpHCA9epMsRBRkni01DuvosT7ZkdA== X-Received: by 2002:a63:894a:: with SMTP id v71mr18476299pgd.451.1635292705358; Tue, 26 Oct 2021 16:58:25 -0700 (PDT) Received: from barry-HP-ProBook-450-G7.hub ([2407:7000:8942:5500:ba8:d828:5ad2:a935]) by smtp.gmail.com with ESMTPSA id ob5sm2054823pjb.30.2021.10.26.16.58.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 26 Oct 2021 16:58:24 -0700 (PDT) From: Barry Song <21cnbao@gmail.com> To: longman@redhat.com Cc: amit.pundir@linaro.org, cgroups@vger.kernel.org, dimitrysh@google.com, groeck@chromium.org, hannes@cmpxchg.org, joel@joelfernandes.org, jsbarnes@google.com, kernel-team@android.com, kerrnel@google.com, linux-kernel@vger.kernel.org, lizefan@huawei.com, peterz@infradead.org, sonnyrao@google.com, tj@kernel.org, vpillai@digitalocean.com Subject: Re: [PATCH RFC] cpuset: Make cpusets get restored on hotplug Date: Wed, 27 Oct 2021 12:58:08 +1300 Message-Id: <20211026235808.34168-1-21cnbao@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <972a5c1b-6721-ac20-cec5-617af67e617d@redhat.com> References: <972a5c1b-6721-ac20-cec5-617af67e617d@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > I think Tejun is concerned about a change in the default behavior of > cpuset v1. > > There is a special v2 mode for cpuset that is enabled by the mount > option "cpuset_v2_mode". This causes the cpuset v1 to adopt some of the > v2 behavior. I introduced this v2 mode a while back to address, I think, > a similar concern. Could you try that to see if it is able to address > your problem? If not, you can make some code adjustment within the > framework of the v2 mode. As long as it is an opt-in, I think we are > open to further change. I am also able to reproduce on Ubuntu 21.04 LTS. all docker will be put in this cgroups and its child cgroups: /sys/fs/cgroup/cpuset/docker disabling and enabling SMT by: echo off > /sys/devices/system/cpu/smt/control echo on > /sys/devices/system/cpu/smt/control or unpluging and pluging CPUs by: echo 0 > /sys/devices/system/cpu/cpuX/online echo 1 > /sys/devices/system/cpu/cpuX/online then all docker images will lose some CPUs. So should we document the broken behaviours somewhere? Thanks barry