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 5595DC43334 for ; Mon, 13 Jun 2022 19:31:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243506AbiFMTbJ (ORCPT ); Mon, 13 Jun 2022 15:31:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33612 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244674AbiFMTaf (ORCPT ); Mon, 13 Jun 2022 15:30:35 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1E7073BBE7; Mon, 13 Jun 2022 10:55:52 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id C34EA1F912; Mon, 13 Jun 2022 17:55:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1655142950; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=AzS01aA3Xyy9CDel2JXDJs9iyrs3QpwSpqahshjzX74=; b=cqnjztUqJrCHTfw9V8Ca5DYeE4hhSffVbVP2M7yHzGtkufmdle7iK/rqZUXXVJWwvILc+6 EdHXTnZWsO2XWqTSSZiB36tUtLKfOeQZOLoNGPczPNYP4F54eWRp6cXpT5TwvRwJNGCBjJ lkBJEdxZ0YrWvHlqX3P3gIIFXIfUN6Q= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 66504134CF; Mon, 13 Jun 2022 17:55:50 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id kb/iFiZ6p2JHEwAAMHmgww (envelope-from ); Mon, 13 Jun 2022 17:55:50 +0000 Date: Mon, 13 Jun 2022 19:55:49 +0200 From: Michal =?iso-8859-1?Q?Koutn=FD?= To: Tejun Heo Cc: Waiman Long , 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 Subject: Re: [PATCH v11 7/8] cgroup/cpuset: Update description of cpuset.cpus.partition in cgroup-v2.rst Message-ID: <20220613175548.GB21665@blackbody.suse.cz> References: <20220510153413.400020-1-longman@redhat.com> <20220510153413.400020-8-longman@redhat.com> <404171dc-0da3-21f2-5003-9718f875e967@redhat.com> <20220613142452.GB6910@blackbody.suse.cz> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="v9Ux+11Zm5mwPlX6" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --v9Ux+11Zm5mwPlX6 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jun 13, 2022 at 07:28:25AM -1000, Tejun Heo wrote: > I see. Is this part even necessary? All the .cpus files of the siblings a= re > owned by the parent who's responsible for configuring both the mode that = the > cgroup subtree is gonna be in and their cpumasks.=20 Do you mean such an example: parent cpuset.cpus=3DSET (root) cpuset.cpus.partition=3Disolated=20 `- child_1 cpuset.cpus=3Dpartition_of(SET) (root) cpuset.cpus.partition= =3Disolated `- ... `- child_n cpuset.cpus=3Dpartition_of(SET) (root) cpuset.cpus.partition= =3Disolated ? I don't think child_*/cpuset.cpus must be owned by root. Actually, the root would only configure the parent, i.e. parent/cpuset.cpus (whose changes would be disallowed to the unprivileged tasks) and the distribution among siblings would up to the whatever runs below. > Given that all the other errors it can make are notified through > "invalid (REASON)" in the mode file, wouldn't it fit better to notify > cpus configuration error the same way too? Do you suggest that a write into child_*/cpuset.cpus that'd not be exclusive wrt a sibling would result in an error string in parent/cpuset.cpus.partition? Thanks, Michal --v9Ux+11Zm5mwPlX6 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- iHUEARYIAB0WIQTrXXag4J0QvXXBmkMkDQmsBEOquQUCYqd6IgAKCRAkDQmsBEOq uTj0AQCj12EX4WPcqDcmcwMKbJzlpJ02i8IqULaAkdHb+ptGcwEA8e1nvXYC0yDJ hezmngAtFbdLR+r20pDT8tTEBO6BKAs= =xTZE -----END PGP SIGNATURE----- --v9Ux+11Zm5mwPlX6--