Re: [PATCH] cpuset: allow empty cpu/node masks

[Konstantin Khlebnikov <khlebnikov@parallels.com>]

Paul Menage wrote:
> On Tue, Apr 19, 2011 at 12:07 PM, Konstantin Khlebnikov
> <khlebnikov@openvz.org>  wrote:
>>
>> This aimed to fix attaching tasks to the newly created cgroups in hierarchies with
>> cpuset subsystem. Cpuset always require initializing cpuset.cpus and cpuset.mems,
>> because they are empty by default, this fact block task attaching with -ENOSPC.
>
> You can set the cgroup.clone_children to 1 to get the parent masks
> automatically copied into the child. So I don't think this patch is
> needed.

cgroup.clone_children does not work if ns_cgroup is mounted,
but it is ok if ns_cgroup is alredy scheduled to remove soon.

However, I still think that all cgroups must have reasonable default state.
Is cgroup.clone_children=1 planned to be default?

So, I just want to make cgroup worked out of the box:

mount -t cgroup cgroup /cgroup
mkdir /cgroup/foo
echo $$ > /cgroup/foo/tasks

Initialization before tasks attaching should be optional.

>
> Paul