1 files changed, 15 insertions, 23 deletions

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 499a264183ef..403387e9a924 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -1810,14 +1810,8 @@ static void worker_enter_idle(struct worker *worker)
 	if (too_many_workers(pool) && !timer_pending(&pool->idle_timer))
 		mod_timer(&pool->idle_timer, jiffies + IDLE_WORKER_TIMEOUT);
 
-	/*
-	 * Sanity check nr_running.  Because unbind_workers() releases
-	 * pool->lock between setting %WORKER_UNBOUND and zapping
-	 * nr_running, the warning may trigger spuriously.  Check iff
-	 * unbind is not in progress.
-	 */
-	WARN_ON_ONCE(!(pool->flags & POOL_DISASSOCIATED) &&
-		     pool->nr_workers == pool->nr_idle &&
+	/* Sanity check nr_running. */
+	WARN_ON_ONCE(pool->nr_workers == pool->nr_idle &&
 		     atomic_read(&pool->nr_running));
 }
 
@@ -4988,21 +4982,12 @@ static void unbind_workers(int cpu)
 
 		pool->flags |= POOL_DISASSOCIATED;
 
-		raw_spin_unlock_irq(&pool->lock);
-
-		for_each_pool_worker(worker, pool) {
-			kthread_set_per_cpu(worker->task, -1);
-			WARN_ON_ONCE(set_cpus_allowed_ptr(worker->task, cpu_possible_mask) < 0);
-		}
-
-		mutex_unlock(&wq_pool_attach_mutex);
-
 		/*
-		 * Sched callbacks are disabled now.  Zap nr_running.
-		 * After this, nr_running stays zero and need_more_worker()
-		 * and keep_working() are always true as long as the
-		 * worklist is not empty.  This pool now behaves as an
-		 * unbound (in terms of concurrency management) pool which
+		 * The handling of nr_running in sched callbacks are disabled
+		 * now.  Zap nr_running.  After this, nr_running stays zero and
+		 * need_more_worker() and keep_working() are always true as
+		 * long as the worklist is not empty.  This pool now behaves as
+		 * an unbound (in terms of concurrency management) pool which
 		 * are served by workers tied to the pool.
 		 */
 		atomic_set(&pool->nr_running, 0);
@@ -5012,9 +4997,16 @@ static void unbind_workers(int cpu)
 		 * worker blocking could lead to lengthy stalls.  Kick off
 		 * unbound chain execution of currently pending work items.
 		 */
-		raw_spin_lock_irq(&pool->lock);
 		wake_up_worker(pool);
+
 		raw_spin_unlock_irq(&pool->lock);
+
+		for_each_pool_worker(worker, pool) {
+			kthread_set_per_cpu(worker->task, -1);
+			WARN_ON_ONCE(set_cpus_allowed_ptr(worker->task, cpu_possible_mask) < 0);
+		}
+
+		mutex_unlock(&wq_pool_attach_mutex);
 	}
 }