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=-15.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,INCLUDES_PULL_REQUEST, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 75515C43331 for ; Mon, 11 Nov 2019 20:22:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 48800206C3 for ; Mon, 11 Nov 2019 20:22:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573503731; bh=Wqbn+tidqU83D7t30PIQyhJur335s0cWd98DIQZWxbg=; h=Date:From:To:Cc:Subject:List-ID:From; b=0c985fjSNYKgHBn54BGjTfUiW1Hg3rBnLa3Lp6TRjSFO3rm4EBSeT7u4ApaVmKAsv vA7UkJjG52dti1glLkR2pLg4ixHjaOrN/GxvHjdv8r5KxhCAQJxdNTAWsza+k3SEiZ c/+jga1C0fGe2rGFJ6HA7faSt1FlYdUZwFwNoMl0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727533AbfKKUWK (ORCPT ); Mon, 11 Nov 2019 15:22:10 -0500 Received: from mail-qt1-f194.google.com ([209.85.160.194]:40954 "EHLO mail-qt1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727811AbfKKUWH (ORCPT ); Mon, 11 Nov 2019 15:22:07 -0500 Received: by mail-qt1-f194.google.com with SMTP id o49so17057268qta.7; Mon, 11 Nov 2019 12:22:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:mime-version :content-disposition:user-agent; bh=Xeq2lcRUVceDqmGyTHaj5d+0Pjk/GmEvYbMYOaMNQzg=; b=I+isjLS5f/apV9ftRVQ09plliCCSpaqV3/UG7fSAdpU4mXCS9TaslJ2OzYYcJa+j4n QSq2fKk559J9ZwzNBSmRcRWOqDKtJFMut2l4D4AysPeV4nNRjuINtm0bSDdbt9IW5WqH fk7DBoj1Gfk75bFq/L1incchih0DAFe4toGXAMySezDb4h0C8qnQ85GO/CZmhr7Xmn2Z YmkIWBnZ5XrTRzEhwYSUSYhKq4/mrelNXQJIAWahBjVhyaHz09RNaDbErBL8JsSE/2Fm nF7x3JxoNiQc4F8UFz+deld6cUww6o5u4xPk2EwGcjDPCXrN1kQZ4MIem70TJeY2ZEmj Rchg== 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 :mime-version:content-disposition:user-agent; bh=Xeq2lcRUVceDqmGyTHaj5d+0Pjk/GmEvYbMYOaMNQzg=; b=WDtNaI/JGyYRTR04uW+IxzxoiRZdJG01GReahRFuLYF7j6gvUDhNkkY7KrHZUw4PWn mVy7htEpiQKIpCCuFxg1TRsoTmTyAuzDah3t4HKfyv9KoQkNCIswL/m0ZRPBWRl+4sR9 eBoDnlLV39VzxYxx/0mNgdpLUPYfNgTMbdZ/NqxQV1go4S1ABmk4P8uR4r3HATQIR7nd 2t/w/3CfGg5lt577XD7OUr3KKr58RkUsPMcd9MxA15kpVA51KEU6C6MgR2zNEoeTLsdP Cam51SKpY6R3VEY+h7m5MEBiMBdTyvJm2nfRPRIjKHhW3q9rpKUU0i5DcZ9qIMprBSUd x2qQ== X-Gm-Message-State: APjAAAVsje4oQLs74AzCHqmQiJUi97udJQ0yGmpO9lKH/z2vMk9t9EYb mo5411ZF8JwkSqM/TH49mIjHRaAG X-Google-Smtp-Source: APXvYqwa00JjUN0TOeR6m2QaHZ1qxjWiq2WnqYCIB/Dud8d6Y2hjnVEpkXsiVWMbx5a69qCX7z3+Ng== X-Received: by 2002:ac8:1084:: with SMTP id a4mr28347343qtj.114.1573503726517; Mon, 11 Nov 2019 12:22:06 -0800 (PST) Received: from localhost ([2620:10d:c091:500::2:d6e0]) by smtp.gmail.com with ESMTPSA id n49sm9587576qtk.94.2019.11.11.12.22.05 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 11 Nov 2019 12:22:05 -0800 (PST) Date: Mon, 11 Nov 2019 12:22:03 -0800 From: Tejun Heo To: Linus Torvalds Cc: linux-kernel@vger.kernel.org, cgroups@vger.kernel.org Subject: [GIT PULL] cgroup fixes for v5.4-rc7 Message-ID: <20191111202203.GC4163745@devbig004.ftw2.facebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Linus. Sorry, I sat on this for too long. There's an inadvertent preemption point in ptrace_stop() which was reliably triggering for a test scenario significantly slowing it down. This pull request contains Oleg's fix to remove the unwanted preemption point. Thanks. The following changes since commit 9e208aa06c2109b45eec6be049a8e47034748c20: Merge tag 'xfs-5.4-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux (2019-10-10 11:47:16 -0700) are available in the Git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git for-5.4-fixes for you to fetch changes up to 937c6b27c73e02cd4114f95f5c37ba2c29fadba1: cgroup: freezer: call cgroup_enter_frozen() with preemption disabled in ptrace_stop() (2019-10-11 08:39:57 -0700) ---------------------------------------------------------------- Oleg Nesterov (1): cgroup: freezer: call cgroup_enter_frozen() with preemption disabled in ptrace_stop() kernel/signal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/signal.c b/kernel/signal.c index c4da1ef56fdf..bcd46f547db3 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2205,8 +2205,8 @@ static void ptrace_stop(int exit_code, int why, int clear_code, kernel_siginfo_t */ preempt_disable(); read_unlock(&tasklist_lock); - preempt_enable_no_resched(); cgroup_enter_frozen(); + preempt_enable_no_resched(); freezable_schedule(); cgroup_leave_frozen(true); } else { -- tejun