Commit 8ac4dbe7 authored by Lai Jiangshan's avatar Lai Jiangshan Committed by Tejun Heo
Browse files

workqueue: Let DISASSOCIATED workers follow unbound wq cpumask changes 



When workqueue cpumask changes are committed, the DISASSOCIATED workers
affinity is not touched and this might be a problem down the line for
isolated setups when the DISASSOCIATED pools still have works to run
after the cpu is offline.

Make sure the workers' affinity is updated every time a workqueue cpumask
changes, so these workers can't break isolation.

Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Waiman Long <longman@redhat.com>
Signed-off-by: default avatarLai Jiangshan <jiangshan.ljs@antgroup.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent e36bce44

kernel/workqueue.c

+13 −0
Original line number Diff line number Diff line
@@ -6926,6 +6926,10 @@ static int workqueue_apply_unbound_cpumask(const cpumask_var_t unbound_cpumask) 
	}



	if (!ret) {

		int cpu;

		struct worker_pool *pool;

		struct worker *worker;



		mutex_lock(&wq_pool_attach_mutex);

		cpumask_copy(wq_unbound_cpumask, unbound_cpumask);

		/* rescuer needs to respect cpumask changes when it is not attached */
@@ -6933,6 +6937,15 @@ static int workqueue_apply_unbound_cpumask(const cpumask_var_t unbound_cpumask) 
			if (wq->rescuer && !wq->rescuer->pool)

				unbind_worker(wq->rescuer);

		}

		/* DISASSOCIATED worker needs to respect wq_unbound_cpumask */

		for_each_possible_cpu(cpu) {

			for_each_cpu_worker_pool(pool, cpu) {

				if (!(pool->flags & POOL_DISASSOCIATED))

					continue;

				for_each_pool_worker(worker, pool)

					unbind_worker(worker);

			}

		}

		mutex_unlock(&wq_pool_attach_mutex);

	}

	return ret;