[ARM] Fix Neponset IRQ handling

[linux-2.6-omap-h63xx.git] / block / ll_rw_blk.c

diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index e5041a02e21f5c7ee4e93597ef95967643380462..7eb36c53f4b7868247141a105ef82e8be3e2d96f 100644 (file)
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -1732,8 +1732,21 @@ 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);
@@ -3439,7 +3452,12 @@ void end_that_request_last(struct request *req, int uptodate)
        if (unlikely(laptop_mode) && blk_fs_request(req))
                laptop_io_completion();
 
-       if (disk && blk_fs_request(req)) {
+       /*
+        * Account IO completion.  bar_rq isn't accounted as a normal
+        * IO on queueing nor completion.  Accounting the containing
+        * request is enough.
+        */
+       if (disk && blk_fs_request(req) && req != &req->q->bar_rq) {
                unsigned long duration = jiffies - req->start_time;
                const int rw = rq_data_dir(req);