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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4CE4AC433EF for ; Mon, 13 Jun 2022 02:50:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230360AbiFMCuO (ORCPT ); Sun, 12 Jun 2022 22:50:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41306 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233238AbiFMCuN (ORCPT ); Sun, 12 Jun 2022 22:50:13 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id AAC16369E9 for ; Sun, 12 Jun 2022 19:50:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1655088611; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=r5H0CNcahQjHmS/4jBwaskIQiBC4tSy1HTQWL7RLcJA=; b=XmmChJPGvEUUkMpBXHSv7MUcI1UjzA1hb4BOZJjvWtot0gyowNX3YlehFiDduQ/b1iKAHd tGsK2IuUvGIwxs3FeOLR3aa0PtR1mRplWZPvV4KXL40tmZl1XkWYctFg4J/iRNHyJzE7rn DdkzV4ZAYLF32Arlv7RIl389IvvS1sg= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-385-FjGOdKJEPMOhyDe_ujr9pg-1; Sun, 12 Jun 2022 22:50:07 -0400 X-MC-Unique: FjGOdKJEPMOhyDe_ujr9pg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id BF27C101AA45; Mon, 13 Jun 2022 02:50:06 +0000 (UTC) Received: from [10.22.16.100] (unknown [10.22.16.100]) by smtp.corp.redhat.com (Postfix) with ESMTP id B9D0D2026D64; Mon, 13 Jun 2022 02:50:05 +0000 (UTC) Message-ID: <23002f21-9dfb-31b4-c6c7-86f4e292dfea@redhat.com> Date: Sun, 12 Jun 2022 22:50:05 -0400 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.0 Subject: Re: [PATCH v11 3/8] cgroup/cpuset: Allow no-task partition to have empty cpuset.cpus.effective Content-Language: en-US To: Tejun Heo Cc: Zefan Li , Johannes Weiner , Jonathan Corbet , Shuah Khan , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, Andrew Morton , Roman Gushchin , Phil Auld , Peter Zijlstra , Juri Lelli , Frederic Weisbecker , Marcelo Tosatti , =?UTF-8?Q?Michal_Koutn=c3=bd?= References: <20220510153413.400020-1-longman@redhat.com> <20220510153413.400020-4-longman@redhat.com> From: Waiman Long In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org On 6/12/22 13:40, Tejun Heo wrote: > Hello, > > Sorry about the long delay. > > On Tue, May 10, 2022 at 11:34:08AM -0400, Waiman Long wrote: >> Once a partition with empty "cpuset.cpus.effective" is formed, no >> new task can be moved into it until "cpuset.cpus.effective" becomes >> non-empty. > This is always true due to no-tasks-in-intermediate-cgroups requirement, > right? I seems to remember there are corner cases where a task can be moved to an intermediate cgroup under circumstances. I need to dig further to find out what it is. Cheers, Longman