Commit d64f2fa0 authored by Juri Lelli's avatar Juri Lelli Committed by Tejun Heo
Browse files

kernel/workqueue: Let rescuers follow unbound wq cpumask changes 



When workqueue cpumask changes are committed the associated rescuer (if
one exists) affinity is not touched and this might be a problem down the
line for isolated setups.

Make sure rescuers affinity is updated every time a workqueue cpumask
changes, so that rescuers can't break isolation.

 [longman: set_cpus_allowed_ptr() will block until the designated task
  is enqueued on an allowed CPU, no wake_up_process() needed. Also use
  the unbound_effective_cpumask() helper as suggested by Tejun.]

Signed-off-by: default avatarJuri Lelli <juri.lelli@redhat.com>
Signed-off-by: default avatarWaiman Long <longman@redhat.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 4c065dbc

kernel/workqueue.c

+5 −0
Original line number Diff line number Diff line
@@ -5051,6 +5051,11 @@ static void apply_wqattrs_commit(struct apply_wqattrs_ctx *ctx) 
	/* update node_nr_active->max */

	wq_update_node_max_active(ctx->wq, -1);



	/* rescuer needs to respect wq cpumask changes */

	if (ctx->wq->rescuer)

		set_cpus_allowed_ptr(ctx->wq->rescuer->task,

				     unbound_effective_cpumask(ctx->wq));



	mutex_unlock(&ctx->wq->mutex);

}