[MTD] Rework the out of band handling completely

[firefly-linux-kernel-4.4.55.git] / block / ll_rw_blk.c

diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index 5b26af8597f3fae3bcb4651186ebb748eaa8583c..eac48bec14791533a594af0e2909b7ed5347c091 100644 (file)
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -1554,7 +1554,7 @@ void blk_plug_device(request_queue_t *q)
         * don't plug a stopped queue, it must be paired with blk_start_queue()
         * which will restart the queueing
         */
-       if (test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags))
+       if (blk_queue_stopped(q))
                return;
 
        if (!test_and_set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) {
@@ -1587,7 +1587,7 @@ EXPORT_SYMBOL(blk_remove_plug);
  */
 void __generic_unplug_device(request_queue_t *q)
 {
-       if (unlikely(test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags)))
+       if (unlikely(blk_queue_stopped(q)))
                return;
 
        if (!blk_remove_plug(q))
@@ -1732,15 +1732,28 @@ void blk_run_queue(struct request_queue *q)
 
        spin_lock_irqsave(q->queue_lock, flags);
        blk_remove_plug(q);
-       if (!elv_queue_empty(q))
-               q->request_fn(q);
+
+       /*
+        * Only recurse once to avoid overrunning the stack, let the unplug
+        * handling reinvoke the handler shortly if we already got there.
+        */
+       if (!elv_queue_empty(q)) {
+               if (!test_and_set_bit(QUEUE_FLAG_REENTER, &q->queue_flags)) {
+                       q->request_fn(q);
+                       clear_bit(QUEUE_FLAG_REENTER, &q->queue_flags);
+               } else {
+                       blk_plug_device(q);
+                       kblockd_schedule_work(&q->unplug_work);
+               }
+       }
+
        spin_unlock_irqrestore(q->queue_lock, flags);
 }
 EXPORT_SYMBOL(blk_run_queue);
 
 /**
  * blk_cleanup_queue: - release a &request_queue_t when it is no longer needed
- * @q:    the request queue to be released
+ * @kobj:    the kobj belonging of the request queue to be released
  *
  * Description:
  *     blk_cleanup_queue is the pair to blk_init_queue() or
@@ -3385,7 +3398,7 @@ static int blk_cpu_notify(struct notifier_block *self, unsigned long action,
 }
 
 
-static struct notifier_block __devinitdata blk_cpu_notifier = {
+static struct notifier_block blk_cpu_notifier = {
        .notifier_call  = blk_cpu_notify,
 };