workqueue: convert BUG_ON()s in __queue_delayed_work() to WARN_ON_ONCE()s
[pandora-kernel.git] / kernel / workqueue.c
index 9954392..7bf068a 100644 (file)
@@ -1146,8 +1146,8 @@ int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
        if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
                unsigned int lcpu;
 
-               BUG_ON(timer_pending(timer));
-               BUG_ON(!list_empty(&work->entry));
+               WARN_ON_ONCE(timer_pending(timer));
+               WARN_ON_ONCE(!list_empty(&work->entry));
 
                timer_stats_timer_set_start_info(&dwork->timer);
 
@@ -1726,10 +1726,9 @@ static void move_linked_works(struct work_struct *work, struct list_head *head,
                *nextp = n;
 }
 
-static void cwq_activate_first_delayed(struct cpu_workqueue_struct *cwq)
+static void cwq_activate_delayed_work(struct work_struct *work)
 {
-       struct work_struct *work = list_first_entry(&cwq->delayed_works,
-                                                   struct work_struct, entry);
+       struct cpu_workqueue_struct *cwq = get_work_cwq(work);
        struct list_head *pos = gcwq_determine_ins_pos(cwq->gcwq, cwq);
 
        trace_workqueue_activate_work(work);
@@ -1738,6 +1737,14 @@ static void cwq_activate_first_delayed(struct cpu_workqueue_struct *cwq)
        cwq->nr_active++;
 }
 
+static void cwq_activate_first_delayed(struct cpu_workqueue_struct *cwq)
+{
+       struct work_struct *work = list_first_entry(&cwq->delayed_works,
+                                                   struct work_struct, entry);
+
+       cwq_activate_delayed_work(work);
+}
+
 /**
  * cwq_dec_nr_in_flight - decrement cwq's nr_in_flight
  * @cwq: cwq of interest
@@ -2045,8 +2052,10 @@ 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
@@ -2628,6 +2637,18 @@ static int try_to_grab_pending(struct work_struct *work)
                smp_rmb();
                if (gcwq == get_work_gcwq(work)) {
                        debug_work_deactivate(work);
+
+                       /*
+                        * A delayed work item cannot be grabbed directly
+                        * because it might have linked NO_COLOR work items
+                        * which, if left on the delayed_list, will confuse
+                        * cwq->nr_active management later on and cause
+                        * stall.  Make sure the work item is activated
+                        * before grabbing.
+                        */
+                       if (*work_data_bits(work) & WORK_STRUCT_DELAYED)
+                               cwq_activate_delayed_work(work);
+
                        list_del_init(&work->entry);
                        cwq_dec_nr_in_flight(get_work_cwq(work),
                                get_work_color(work),