Re: [PATCH v4 3/6] memcg: fast hierarchy-aware child test.

Kamezawa Hiroyuki
2013-01-29T00:14:51Z

(2013/01/22 22:47), Glauber Costa wrote:
> Currently, we use cgroups' provided list of children to verify if it is
> safe to proceed with any value change that is dependent on the cgroup
> being empty.
>
> This is less than ideal, because it enforces a dependency over cgroup
> core that we would be better off without. The solution proposed here is
> to iterate over the child cgroups and if any is found that is already
> online, we bounce and return: we don't really care how many children we
> have, only if we have any.
>
> This is also made to be hierarchy aware. IOW, cgroups with hierarchy
> disabled, while they still exist, will be considered for the purpose of
> this interface as having no children.
>
> Signed-off-by: Glauber Costa <glommer@parallels.com>
> Acked-by: Michal Hocko <mhocko@suse.cz>

Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>