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.
Signed-off-by: Waiman Long longman@redhat.com Reviewed-by: Michal Koutný mkoutny@suse.com --- kernel/cgroup/cpuset.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index f310915d1257..5b8d763555b0 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -3516,6 +3516,8 @@ static void cpuset_hotplug_update_tasks(struct cpuset *cs, struct tmpmasks *tmp) update_tasks: cpus_updated = !cpumask_equal(&new_cpus, cs->effective_cpus); mems_updated = !nodes_equal(new_mems, cs->effective_mems); + if (!cpus_updated && !mems_updated) + goto unlock; /* Hotplug doesn't affect this cpuset */
if (mems_updated) check_insane_mems_config(&new_mems); @@ -3527,6 +3529,7 @@ static void cpuset_hotplug_update_tasks(struct cpuset *cs, struct tmpmasks *tmp) hotplug_update_tasks_legacy(cs, &new_cpus, &new_mems, cpus_updated, mems_updated);
+unlock: percpu_up_write(&cpuset_rwsem); }