On Sat, Dec 25, 2021 at 12:09:32AM +0000, Wei Yang <richard.weiyang@xxxxxxxxx> wrote:
> This means we can remove the check on ->updated_next, if we make sure
> the subtree from @root is on list, which could be done by checking
> updated_next for root.
Nice refactoring.
> @@ -96,9 +97,12 @@ static struct cgroup *cgroup_rstat_cpu_pop_updated(struct cgroup *pos,
> * We're gonna walk down to the first leaf and visit/remove it. We
> * can pick whatever unvisited node as the starting point.
> */
> - if (!pos)
> + if (!pos) {
> pos = root;
> - else
> + // return NULL if this subtree is not on-list
> + if (!cgroup_rstat_cpu(pos, cpu)->updated_next)
> + return NULL;
> + } else
+ /* return NULL if this subtree is not on-list */
Just a coding style nitpick.
The patch is otherwise
Reviewed-by: Michal Koutný <mkoutny@xxxxxxxx>
