workqueue: move rescuer pool detachment to the end
In 51697d393922 ("workqueue: use generic attach/detach routine for
rescuers"), The rescuer detaches itself from the pool before put_pwq()
so that the put_unbound_pool() will not destroy the rescuer-attached
pool.
It is unnecessary. worker_detach_from_pool() can be used as the last
statement to access to the pool just like the regular workers,
put_unbound_pool() will wait for it to detach and then free the pool.
So we move the worker_detach_from_pool() down, make it coincide with
the regular workers.
tj: Minor description update.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 4cb8527..4d9600f 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -2253,15 +2253,10 @@
move_linked_works(work, scheduled, &n);
process_scheduled_works(rescuer);
- spin_unlock_irq(&pool->lock);
-
- worker_detach_from_pool(rescuer, pool);
-
- spin_lock_irq(&pool->lock);
/*
* Put the reference grabbed by send_mayday(). @pool won't
- * go away while we're holding its lock.
+ * go away while we're still attached to it.
*/
put_pwq(pwq);
@@ -2274,8 +2269,11 @@
wake_up_worker(pool);
rescuer->pool = NULL;
- spin_unlock(&pool->lock);
- spin_lock(&wq_mayday_lock);
+ spin_unlock_irq(&pool->lock);
+
+ worker_detach_from_pool(rescuer, pool);
+
+ spin_lock_irq(&wq_mayday_lock);
}
spin_unlock_irq(&wq_mayday_lock);