From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal =?utf-8?Q?Koutn=C3=BD?= Subject: Re: [PATCH 1/3] cgroup/cpuset: Make cpuset_fork() handle CLONE_INTO_CGROUP properly Date: Mon, 3 Apr 2023 18:55:23 +0200 Message-ID: <20230403165523.aphsec2epqi72k27@blackpad> References: <20230331145045.2251683-1-longman@redhat.com> <20230331145045.2251683-2-longman@redhat.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="hqjzbb4yslshnocc" Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1680540924; 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=YjHTDLKnu47Af8/RYRI8Ep8eWiGDBHSZDf7lS1gT7w8=; b=CEfOfG3UaWRbtseNKY9DpsYv+24G2DErlSrzrBLWXwn7D9NOSFcy7jOqZsSWAfOKQNB9vC w0OKgbKTVzYTREfxDKWgjtGaNzyYHCFpfTVzLWYiCgrnFjS4xOKNhnoFEkauyNHAIded4E 9b1BuHPOi+OUq7CGt3aCyfpOT1O7Hcs= Content-Disposition: inline In-Reply-To: <20230331145045.2251683-2-longman-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> List-ID: To: Waiman Long Cc: Tejun Heo , Zefan Li , Johannes Weiner , Christian Brauner , cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Juri Lelli , Dietmar Eggemann , gscrivan-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org --hqjzbb4yslshnocc Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Mar 31, 2023 at 10:50:43AM -0400, Waiman Long = wrote: > By default, the clone(2) syscall spawn a child process into the same > cgroup as its parent. With the use of the CLONE_INTO_CGROUP flag > introduced by commit ef2c41cf38a7 ("clone3: allow spawning processes > into cgroups"), the child will be spawned into a different cgroup which > is somewhat similar to writing the child's tid into "cgroup.threads". >=20 > The current cpuset_fork() method does not properly handle the > CLONE_INTO_CGROUP case where the cpuset of the child may be different > from that of its parent. Update the cpuset_fork() method to treat the > CLONE_INTO_CGROUP case similar to cpuset_attach(). Should .can_fork=3Dcpuset_can_fork in analogy to cpuset_can_attach be also devised? (Sorry if I missed that in the previous discussion.) >=20 > Since the newly cloned task has not been running yet, its actual > memory usage isn't known. So it is not necessary to make change to mm > in cpuset_fork(). >=20 > Fixes: ef2c41cf38a7 ("clone3: allow spawning processes into cgroups") > Signed-off-by: Waiman Long Thanks, Michal --hqjzbb4yslshnocc Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTrXXag4J0QvXXBmkMkDQmsBEOquQUCZCsE9gAKCRAkDQmsBEOq uXNEAP4yZWUDQPS5MdBJKxg7KPFXijvx7boOQCgxkNjZYray+wD+JXdFvFEi1rKM oOJu9alNdUlt9cXh0vK+1QGgfk7KggQ= =9fk7 -----END PGP SIGNATURE----- --hqjzbb4yslshnocc--