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=-8.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 9B513C33C9E for ; Fri, 17 Jan 2020 18:41:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6FFEC2072B for ; Fri, 17 Jan 2020 18:41:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="pya+t3lj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727573AbgAQSln (ORCPT ); Fri, 17 Jan 2020 13:41:43 -0500 Received: from mail-wr1-f65.google.com ([209.85.221.65]:32981 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727115AbgAQSln (ORCPT ); Fri, 17 Jan 2020 13:41:43 -0500 Received: by mail-wr1-f65.google.com with SMTP id b6so23734288wrq.0 for ; Fri, 17 Jan 2020 10:41:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=Hl2KZMvca+Q8kuDbq/WhLs/Rb2uaYU/dE+p/JdLh8Ok=; b=pya+t3ljvih0NEjKSrRArdnH313MxZONXt8kTq2RCSmOCsZP7KR3baPZAFPehTPQxx VuKQfkLNIc4O7hDdNydFUo+Rit+LleyvNPqIqy5948KMTJxnyj2MVgDSFofqnZqQS5Nx Or3Zo594/EnJk39EWoCRDMjG4V8NF2BmHRXws3l/1nFpofa/+Bvxs6YNhCcdsqG7x3wk vR24AbaUtYr8X6KA5iQGuwz6Z7LgbIrcG2vC/4HLMaSGjk6nSLQU3vF89b7ikkhwAMpc A800IqSQpGRJuHLz6yxrYHsfaVbVemOGjrYeY0sTZTYGZtjBtpiMZzaKyNvlSn/ysOZH U/KQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=Hl2KZMvca+Q8kuDbq/WhLs/Rb2uaYU/dE+p/JdLh8Ok=; b=PUZ6nw8LPDs8QaC+6O73vqoMwKWfXk4K32mSzM6iKamJjrl3JNp0d++AZG8UX7vD75 IRXr0hBUJtb8pgDeSU7JRVBqRRHipi/FhRUJwB62rleTvuDkmy7DI0fq84sfHXKj63iW X0BCr2wIv/SR+deyzjroiHd5WMbZX6FSaVqnwWjk3cPJZS1HsV4d274tCCSeqRgeU5ac xFsjOYwOFpGgJYpDHPsruBmOHWFxaJRUQvCSybNvWECP6JCD3a0htBvbi0jhgx7Nmghv Uvd3LThBn7pvrYg+RIcljh+bC9KwVtPRvtZ9CHe6vlvPlB2wwaZ9vi6IWLXc/IB0dSLr 8wVw== X-Gm-Message-State: APjAAAXbs8KMc89NKpTge6Xh+gAYN3BubCemqtxpgKlCi0M3inWkZf3D dgNCEo2UB5+upJFsrTqQfWa1e2ThxwvPiUEDqNPG7g== X-Google-Smtp-Source: APXvYqy7GEdReDU3nlMa6hYZ9OrqeU0qE5bnCgOzJN8pNOYKrSXVI8Xbd+U1s/kjHmCr0FVwMIzZK3FVc56LwsF0buY= X-Received: by 2002:adf:e887:: with SMTP id d7mr4490076wrm.162.1579286500370; Fri, 17 Jan 2020 10:41:40 -0800 (PST) MIME-Version: 1.0 References: <20200116043612.52782-1-surenb@google.com> <20200117151533.12381-1-mkoutny@suse.com> <20200117151533.12381-3-mkoutny@suse.com> <20200117172806.GK2677547@devbig004.ftw2.facebook.com> In-Reply-To: <20200117172806.GK2677547@devbig004.ftw2.facebook.com> From: Suren Baghdasaryan Date: Fri, 17 Jan 2020 10:41:29 -0800 Message-ID: Subject: Re: [PATCH 2/3] cgroup: Iterate tasks that did not finish do_exit() To: Tejun Heo Cc: =?UTF-8?Q?Michal_Koutn=C3=BD?= , cgroups mailinglist , Johannes Weiner , Li Zefan , alex.shi@linux.alibaba.com, Roman Gushchin , kernel-team , JeiFeng Lee , linux-arm-kernel@lists.infradead.org, LKML , linux-kselftest@vger.kernel.org, linux-mediatek@lists.infradead.org, matthias.bgg@gmail.com, shuah@kernel.org, Tom Cherry Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org On Fri, Jan 17, 2020 at 9:28 AM Tejun Heo wrote: > > On Fri, Jan 17, 2020 at 04:15:32PM +0100, Michal Koutn=C3=BD 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_EXITIN= G > > 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 dyin= g > > leaders with live threads in PROCS iterations") but it may be reviewed > > later. Tested-by: Suren Baghdasaryan > > Yeah, this looks fine to me. Any chance you can order this before the > clean up so that we can mark it for -stable. > +1 for reordering. Makes it easier to backport. Thanks, Suren. > Thanks. > > -- > tejun > > -- > To unsubscribe from this group and stop receiving emails from it, send an= email to kernel-team+unsubscribe@android.com. >