1 files changed, 20 insertions, 8 deletions

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 042d221d33cc..fbc6576a83c3 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -739,8 +739,10 @@ void wq_worker_waking_up(struct task_struct *task, unsigned int cpu)
 {
         struct worker *worker = kthread_data(task);
 
-        if (!(worker->flags & WORKER_NOT_RUNNING))
+        if (!(worker->flags & WORKER_NOT_RUNNING)) {
+                WARN_ON_ONCE(worker->pool->gcwq->cpu != cpu);
                 atomic_inc(get_pool_nr_running(worker->pool));
+        }
 }
 
 /**
@@ -1361,8 +1363,19 @@ static void __queue_delayed_work(int cpu, struct workqueue_struct *wq,
 
         WARN_ON_ONCE(timer->function != delayed_work_timer_fn ||
                      timer->data != (unsigned long)dwork);
-        BUG_ON(timer_pending(timer));
-        BUG_ON(!list_empty(&work->entry));
+        WARN_ON_ONCE(timer_pending(timer));
+        WARN_ON_ONCE(!list_empty(&work->entry));
+
+        /*
+         * If @delay is 0, queue @dwork->work immediately.  This is for
+         * both optimization and correctness.  The earliest @timer can
+         * expire is on the closest next tick and delayed_work users depend
+         * on that there's no such delay when @delay is 0.
+         */
+        if (!delay) {
+                __queue_work(cpu, wq, &dwork->work);
+                return;
+        }
 
         timer_stats_timer_set_start_info(&dwork->timer);
 
@@ -1417,9 +1430,6 @@ bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
         bool ret = false;
         unsigned long flags;
 
-        if (!delay)
-                return queue_work_on(cpu, wq, &dwork->work);
-
         /* read the comment in __queue_work() */
         local_irq_save(flags);
 
@@ -2407,8 +2417,10 @@ static int rescuer_thread(void *__wq)
 repeat:
         set_current_state(TASK_INTERRUPTIBLE);
 
-        if (kthread_should_stop())
+        if (kthread_should_stop()) {
+                __set_current_state(TASK_RUNNING);
                 return 0;
+        }
 
         /*
          * See whether any cpu is asking for help.  Unbounded
@@ -3475,7 +3487,7 @@ unsigned int work_busy(struct work_struct *work)
         unsigned int ret = 0;
 
         if (!gcwq)
-                return false;
+                return 0;
 
         spin_lock_irqsave(&gcwq->lock, flags);