Commits
Tejun Heo committed 1a574231669
cgroup: make hierarchy_id use cyclic idr We want to be able to lookup a hierarchy from its id and cyclic allocation is a whole lot simpler with idr. Convert to idr and use idr_alloc_cyclc(). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>