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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 CC43AC433B4 for ; Tue, 18 May 2021 09:48:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B162D613DF for ; Tue, 18 May 2021 09:48:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348116AbhERJta (ORCPT ); Tue, 18 May 2021 05:49:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:50024 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348124AbhERJtU (ORCPT ); Tue, 18 May 2021 05:49:20 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 987FB613CA; Tue, 18 May 2021 09:47:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1621331282; bh=NvwSaFd4j1U9x7MuiRuhuzS0QYyzwo36gVpUtBca09k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PrnyXh5dDh1IBvExWmit09/FbBGiBbuPKeY+VMUJw8xXrf5z1gD6Mq5/GTrEf2e53 Ss1XprfORyl2NnRvt2oGg1RpmHMV4Sjwk3oZA/1j83FYtPvuXxNZlmJhlMNbUSwpwP kE14LKvtyOjuJLTLLTA6KK+VT/JmdQbX/Ul4WJO7mqzTR43GDkfe+CAuBWI/8jbR6U zQsSsD5Ykng8/nOF2AZ9uIo1azDZZUcBsMqZ9GCQ6MQGB9j6WjwXcFyHtp4pO8b6Z6 LmF2ljTd4DQIiYNwlltUyhN9v/4/J+y+n+oKeZzyXYC9X8mdtWS3U1Wavdlm3prYkT 7ArvJUG2dnRDg== From: Will Deacon To: linux-arm-kernel@lists.infradead.org Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Will Deacon , Catalin Marinas , Marc Zyngier , Greg Kroah-Hartman , Peter Zijlstra , Morten Rasmussen , Qais Yousef , Suren Baghdasaryan , Quentin Perret , Tejun Heo , Li Zefan , Johannes Weiner , Ingo Molnar , Juri Lelli , Vincent Guittot , "Rafael J. Wysocki" , kernel-team@android.com Subject: [PATCH v6 07/21] cpuset: Don't use the cpu_possible_mask as a last resort for cgroup v1 Date: Tue, 18 May 2021 10:47:11 +0100 Message-Id: <20210518094725.7701-8-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210518094725.7701-1-will@kernel.org> References: <20210518094725.7701-1-will@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org If the scheduler cannot find an allowed CPU for a task, cpuset_cpus_allowed_fallback() will widen the affinity to cpu_possible_mask if cgroup v1 is in use. In preparation for allowing architectures to provide their own fallback mask, just return early if we're either using cgroup v1 or we're using cgroup v2 with a mask that contains invalid CPUs. This will allow select_fallback_rq() to figure out the mask by itself. Cc: Li Zefan Cc: Tejun Heo Cc: Johannes Weiner Reviewed-by: Quentin Perret Signed-off-by: Will Deacon --- include/linux/cpuset.h | 1 + kernel/cgroup/cpuset.c | 12 ++++++++++-- 2 files changed, 11 insertions(+), 2 deletions(-) diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h index 04c20de66afc..ed6ec677dd6b 100644 --- a/include/linux/cpuset.h +++ b/include/linux/cpuset.h @@ -15,6 +15,7 @@ #include #include #include +#include #include #ifdef CONFIG_CPUSETS diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index a945504c0ae7..8c799260a4a2 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -3322,9 +3322,17 @@ void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask) void cpuset_cpus_allowed_fallback(struct task_struct *tsk) { + const struct cpumask *cs_mask; + const struct cpumask *possible_mask = task_cpu_possible_mask(tsk); + rcu_read_lock(); - do_set_cpus_allowed(tsk, is_in_v2_mode() ? - task_cs(tsk)->cpus_allowed : cpu_possible_mask); + cs_mask = task_cs(tsk)->cpus_allowed; + + if (!is_in_v2_mode() || !cpumask_subset(cs_mask, possible_mask)) + goto unlock; /* select_fallback_rq will try harder */ + + do_set_cpus_allowed(tsk, cs_mask); +unlock: rcu_read_unlock(); /* -- 2.31.1.751.gd2f1c929bd-goog