Re: [PATCH 1/3] mm: memcontrol: fix swap counter leak on swapout from offline cgroup

[Michal Hocko]

On Mon 01-08-16 16:26:24, Vladimir Davydov wrote:
[...]
> +static struct mem_cgroup *mem_cgroup_id_get_active(struct mem_cgroup *memcg)
> +{
> +	while (!atomic_inc_not_zero(&memcg->id.ref))
> +		memcg = parent_mem_cgroup(memcg);
> +	return memcg;
> +}

Does this actually work properly? Say we have root -> A so parent is
NULL if root (use_hierarchy == false).
-- 
Michal Hocko
SUSE Labs