From mboxrd@z Thu Jan 1 00:00:00 1970 From: Waiman Long Subject: Re: [PATCH 1/3] cgroup/cpuset: Make cpuset_fork() handle CLONE_INTO_CGROUP properly Date: Thu, 6 Apr 2023 10:08:31 -0400 Message-ID: References: <20230331145045.2251683-1-longman@redhat.com> <20230331145045.2251683-2-longman@redhat.com> <20230406-vernommen-kurieren-e75f4ee6ea96@brauner> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1680790115; 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=KANTDl9cP5Foo4kRIPvE9J1MD539S2x+RsUY14Y5myk=; b=GL7D/8C42kG2g7grhmGLPqp0XAvYTq2LLJrAYN6YOUC6DaswCRPKMhvCLIGd0vd+P3kRdZ q3NkZN8Ni27tQSIlPgnaLPIg0CzpydtEAOeUmoKRANBeESZTgHSkrWnYvAb2BAERmFqnfQ QsZlyIwyo0+Ve5BqnEDfjzYAg2NFmM0= Content-Language: en-US In-Reply-To: <20230406-vernommen-kurieren-e75f4ee6ea96@brauner> List-ID: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Christian Brauner Cc: Tejun Heo , Zefan Li , Johannes Weiner , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Juri Lelli , Dietmar Eggemann , gscrivan@redhat.com On 4/6/23 05:45, Christian Brauner wrote: > 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". >> >> 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(). >> >> 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(). >> >> Fixes: ef2c41cf38a7 ("clone3: allow spawning processes into cgroups") >> Signed-off-by: Waiman Long >> --- > Just two nits. I think this needs a Cc stable and it would be nice if > you could give Giuseppe a "Reported-by". The presence of a fixes tag should make this patch picked up by stable. Yes, I will cc stable when I need to update the patch next time. Right, I should have added Reported-by: Giuseppe Scrivano Cheers, Longman