Re: [PATCH 1/5] cgroup/cpuset: Skip task update if hotplug doesn't affect current cpuset

On Mon, Mar 06, 2023 at 03:08:45PM -0500, Waiman Long longman@redhat.com wrote:

If a hotplug event doesn't affect the current cpuset, there is no point to call hotplug_update_tasks() or hotplug_update_tasks_legacy(). So just skip it.

This skips "insane" modification of cs->cpus_allowed in hotplug_update_tasks_legacy() but assuming cs->cpus_allowed is kept in sync with cs->effective_cpus on v1, it is OK to skip the update based only on effective_cpus check.

Hence,

kernel/cgroup/cpuset.c | 3 +++ 1 file changed, 3 insertions(+)

Reviewed-by: Michal Koutný mkoutny@suse.com