block: move queue run on unplug to kblockd

[pandora-kernel.git] / block / blk-core.c

diff --git a/block/blk-core.c b/block/blk-core.c
index d20ce1e..36b1a75 100644 (file)
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -198,19 +198,6 @@ void blk_dump_rq_flags(struct request *rq, char *msg)
 }
 EXPORT_SYMBOL(blk_dump_rq_flags);
 
-/*
- * Make sure that plugs that were pending when this function was entered,
- * are now complete and requests pushed to the queue.
-*/
-static inline void queue_sync_plugs(struct request_queue *q)
-{
-       /*
-        * If the current process is plugged and has barriers submitted,
-        * we will livelock if we don't unplug first.
-        */
-       blk_flush_plug(current);
-}
-
 static void blk_delay_work(struct work_struct *work)
 {
        struct request_queue *q;
@@ -298,7 +285,6 @@ void blk_sync_queue(struct request_queue *q)
 {
        del_timer_sync(&q->timeout);
        cancel_delayed_work_sync(&q->delay_work);
-       queue_sync_plugs(q);
 }
 EXPORT_SYMBOL(blk_sync_queue);
 
@@ -1311,7 +1297,15 @@ get_rq:
 
        plug = current->plug;
        if (plug) {
-               if (!plug->should_sort && !list_empty(&plug->list)) {
+               /*
+                * If this is the first request added after a plug, fire
+                * of a plug trace. If others have been added before, check
+                * if we have multiple devices in this plug. If so, make a
+                * note to sort the list before dispatch.
+                */
+               if (list_empty(&plug->list))
+                       trace_block_plug(q);
+               else if (!plug->should_sort) {
                        struct request *__rq;
 
                        __rq = list_entry_rq(plug->list.prev);
@@ -2671,7 +2665,10 @@ static int plug_rq_cmp(void *priv, struct list_head *a, struct list_head *b)
 static void queue_unplugged(struct request_queue *q, unsigned int depth)
 {
        trace_block_unplug_io(q, depth);
-       __blk_run_queue(q, false);
+       __blk_run_queue(q, true);
+
+       if (q->unplugged_fn)
+               q->unplugged_fn(q);
 }
 
 static void flush_plug_list(struct blk_plug *plug)
@@ -2696,6 +2693,11 @@ static void flush_plug_list(struct blk_plug *plug)
 
        q = NULL;
        depth = 0;
+
+       /*
+        * Save and disable interrupts here, to avoid doing it for every
+        * queue lock we have to take.
+        */
        local_irq_save(flags);
        while (!list_empty(&list)) {
                rq = list_entry_rq(list.next);