Commit 6667439f authored by Waiman Long's avatar Waiman Long Committed by Tejun Heo

cgroup/cpuset: Include offline CPUs when tasks' cpumasks in top_cpuset are updated

Similar to commit 3fb906e7 ("group/cpuset: Don't filter offline
CPUs in cpuset_cpus_allowed() for top cpuset tasks"), the whole set of
possible CPUs including offline ones should be used for setting cpumasks
for tasks in the top cpuset when a cpuset partition is modified as the
hotplug code won't update cpumasks for tasks in the top cpuset when
CPUs become online or offline.
Signed-off-by: default avatarWaiman Long <longman@redhat.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent df59b72c
......@@ -1209,7 +1209,9 @@ void rebuild_sched_domains(void)
*
* Iterate through each task of @cs updating its cpus_allowed to the
* effective cpuset's. As this function is called with cpuset_rwsem held,
* cpuset membership stays stable.
* cpuset membership stays stable. For top_cpuset, task_cpu_possible_mask()
* is used instead of effective_cpus to make sure all offline CPUs are also
* included as hotplug code won't update cpumasks for tasks in top_cpuset.
*/
static void update_tasks_cpumask(struct cpuset *cs, struct cpumask *new_cpus)
{
......@@ -1219,15 +1221,18 @@ static void update_tasks_cpumask(struct cpuset *cs, struct cpumask *new_cpus)
css_task_iter_start(&cs->css, 0, &it);
while ((task = css_task_iter_next(&it))) {
const struct cpumask *possible_mask = task_cpu_possible_mask(task);
if (top_cs) {
/*
* Percpu kthreads in top_cpuset are ignored
*/
if (top_cs && (task->flags & PF_KTHREAD) &&
kthread_is_per_cpu(task))
if ((task->flags & PF_KTHREAD) && kthread_is_per_cpu(task))
continue;
cpumask_and(new_cpus, cs->effective_cpus,
task_cpu_possible_mask(task));
cpumask_andnot(new_cpus, possible_mask, cs->subparts_cpus);
} else {
cpumask_and(new_cpus, possible_mask, cs->effective_cpus);
}
set_cpus_allowed_ptr(task, new_cpus);
}
css_task_iter_end(&it);
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment