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charset=us-ascii Content-Disposition: inline In-Reply-To: <20240415053550.538722-1-svens@linux.ibm.com> Hello, On Mon, Apr 15, 2024 at 07:35:49AM +0200, Sven Schnelle wrote: > @@ -1277,7 +1277,8 @@ static bool kick_pool(struct worker_pool *pool) > !cpumask_test_cpu(p->wake_cpu, pool->attrs->__pod_cpumask)) { > struct work_struct *work = list_first_entry(&pool->worklist, > struct work_struct, entry); > - p->wake_cpu = cpumask_any_distribute(pool->attrs->__pod_cpumask); > + p->wake_cpu = cpumask_any_and_distribute(pool->attrs->__pod_cpumask, > + cpu_online_mask); I think this can still race with the last CPU in the pod going down and return nr_cpu_ids. Maybe something like the following would be better? int wake_cpu; wake_cpu = cpumask_any_distribute_and(...); if (wake_cpu < nr_cpus_ids) { p->wake_cpu = wake_cpu; // update stat; } This generally seems like a good idea but isn't this still racy? The CPU may go down between setting p->wake_cpu and wake_up_process(). Thanks. -- tejun