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=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 D9937C33CB3 for ; Fri, 17 Jan 2020 17:28:14 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B0A192083E for ; Fri, 17 Jan 2020 17:28:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="TcWtPhqw"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="DbHiqO+e" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B0A192083E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=LKb8LrFkcGtn3Kz1cKgLx+XStVpvi8Jd1SJtZ8X7Yy4=; b=TcWtPhqwUs21KO nwNZ03Dl8nMjhPFtX+whYf2ru/yzlggfXdsUCmy7Ot/SUZ6Ih35J3J1w1X65vZE+Swvz0UjHrgbyH 0LYu5FcRb+TnltiL2lh9DlOAvq4R5wuFn1HPrLVUsPUyNv22m5y7/NXrIZ0McXmUSJDzjZLmJoH/m NUIXtK7eGn3uHbhBEWvirAQPF5xYit8hU0aYO0vcw+Up9DUmx5YEOQEfWC5WQDqoiFc4ODm+B9lhl cuCBi8+8OFkbMX4LZX8BCEWh+vFA26KhN0derF95M7dZPTk+g/wwheLzCyedlwa0mEhBiT2LJTxU6 zCP08u9PBcDSnG2rGnYg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1isVPp-0007Us-UN; Fri, 17 Jan 2020 17:28:13 +0000 Received: from mail-qt1-x841.google.com ([2607:f8b0:4864:20::841]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1isVPn-0007UC-RD; Fri, 17 Jan 2020 17:28:13 +0000 Received: by mail-qt1-x841.google.com with SMTP id i13so22352213qtr.3; Fri, 17 Jan 2020 09:28:09 -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:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=YJBe+PR1JTzkbV6VdX/ClFM8UuTfYuVGKNcb10Up+LM=; b=DbHiqO+e6kYuR6bMRUFqkRzJXzREnc/t8WeVUwNtwBq0US0ALqFtfBS3k8Ar5PzFae jpbiR7Ax+NvFzgNUZfzP6b4KBWdJJ8us7/sDH5Tiro8mnHYZM1bos9P/GDhAcxVHXG4b +CqRW+gbtb40Tq4JQ9+XfDuAtGc8xx7XWoPbLCDa9sXO0xSMc54OuWYlMPO3hMfg3xGs R6SRfw70eNBH9z1vinkvQf3Pkmv//DOGZzpDO/JeaaQZKfMlTJoC34/zqw6bnCacSApd hf6+skAgQQBrKH5W5od7c18HNBincCZTYsXdKlpO3ehhcjXZitzgNqPGCAFsoZlAoM4q MvUg== 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 :content-transfer-encoding:in-reply-to:user-agent; bh=YJBe+PR1JTzkbV6VdX/ClFM8UuTfYuVGKNcb10Up+LM=; b=OWymrAHYj6KgH4ABUmnAiA9NifrbUZsha/lQpVebFvHqU0nOu+ihpauO26wQ0K/huK gcwB+xt2nL22yi1SDdHvR92pdn4T0wpPcelvJHxjBYbBuLt2uz3Fq4HdYW3DKJbh9t8K G5t9JgNblbrW+vahVlhi3IAOPmFp2eJmDVRl+u2864v4qDolMcZJdJfWtHvULsCEBBjI lqQ4DzfxLLu95Cxjjs45XL+eKI3N3G3RbwXm+dkRb6cVO977+NhaCJPef0a9kVT4Nk/i 0VCkxdLw27dKoi/3OFES5bhyXtJjcBpLjiC6dAvxfxIVwocZY2g+ZulJhk/S2Qu58zIj s+Qw== X-Gm-Message-State: APjAAAUuzIyUoTgJm1nzIrlF0Y/vLZ+rbUf7JCrqx8H6YpZKuWgWAHeE Rl9Nzk9hP6sY/gwvtHEfLEA= X-Google-Smtp-Source: APXvYqz2O/xFh6ygdxVfF7TRwAgb6tMQGsH1goOEKwF730KRP0mdEDko+yi0ag0UIHTaUnjOw9qRYQ== X-Received: by 2002:aed:2150:: with SMTP id 74mr8430727qtc.323.1579282089045; Fri, 17 Jan 2020 09:28:09 -0800 (PST) Received: from localhost ([2620:10d:c091:500::1:7d10]) by smtp.gmail.com with ESMTPSA id r37sm13251937qtj.44.2020.01.17.09.28.08 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 17 Jan 2020 09:28:08 -0800 (PST) Date: Fri, 17 Jan 2020 09:28:06 -0800 From: Tejun Heo To: Michal =?iso-8859-1?Q?Koutn=FD?= Subject: Re: [PATCH 2/3] cgroup: Iterate tasks that did not finish do_exit() Message-ID: <20200117172806.GK2677547@devbig004.ftw2.facebook.com> References: <20200116043612.52782-1-surenb@google.com> <20200117151533.12381-1-mkoutny@suse.com> <20200117151533.12381-3-mkoutny@suse.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200117151533.12381-3-mkoutny@suse.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200117_092811_883227_703D9FD0 X-CRM114-Status: UNSURE ( 9.77 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linger.lee@mediatek.com, tomcherry@google.com, shuah@kernel.org, linux-kernel@vger.kernel.org, Li Zefan , linux-mediatek@lists.infradead.org, linux-kselftest@vger.kernel.org, Johannes Weiner , matthias.bgg@gmail.com, cgroups@vger.kernel.org, alex.shi@linux.alibaba.com, kernel-team@android.com, guro@fb.com, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Jan 17, 2020 at 04:15:32PM +0100, Michal Koutn=FD wrote: > PF_EXITING is set earlier than actual removal from css_set when a task > is exitting. This can confuse cgroup.procs readers who see no PF_EXITING > tasks, however, rmdir is checking against css_set membership so it can > transitionally fail with EBUSY. > = > Fix this by listing tasks that weren't unlinked from css_set active > lists. > It may happen that other users of the task iterator (without > CSS_TASK_ITER_PROCS) spot a PF_EXITING task before cgroup_exit(). This > is equal to the state before commit c03cd7738a83 ("cgroup: Include dying > leaders with live threads in PROCS iterations") but it may be reviewed > later. Yeah, this looks fine to me. Any chance you can order this before the clean up so that we can mark it for -stable. Thanks. -- = tejun _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel