[PATCH] blk: branch hints

Sprinkle around a few branch hints in the block layer.

Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 6 insertions, 6 deletions

diff --git a/drivers/block/ll_rw_blk.c b/drivers/block/ll_rw_blk.c
index 265de858d4de..1e847151c3a3 100644
--- a/drivers/block/ll_rw_blk.c
+++ b/drivers/block/ll_rw_blk.c
@@ -1439,7 +1439,7 @@ EXPORT_SYMBOL(blk_remove_plug);
  */
 void __generic_unplug_device(request_queue_t *q)
 {
-        if (test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags))
+        if (unlikely(test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags)))
                 return;
 
         if (!blk_remove_plug(q))
@@ -1763,7 +1763,7 @@ EXPORT_SYMBOL(blk_init_queue_node);
 
 int blk_get_queue(request_queue_t *q)
 {
-        if (!test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)) {
+        if (likely(!test_bit(QUEUE_FLAG_DEAD, &q->queue_flags))) {
                 atomic_inc(&q->refcnt);
                 return 0;
         }
@@ -2584,7 +2584,7 @@ static int __make_request(request_queue_t *q, struct bio *bio)
         spin_lock_prefetch(q->queue_lock);
 
         barrier = bio_barrier(bio);
-        if (barrier && (q->ordered == QUEUE_ORDERED_NONE)) {
+        if (unlikely(barrier) && (q->ordered == QUEUE_ORDERED_NONE)) {
                 err = -EOPNOTSUPP;
                 goto end_io;
         }
@@ -2685,7 +2685,7 @@ get_rq:
         /*
          * REQ_BARRIER implies no merging, but lets make it explicit
          */
-        if (barrier)
+        if (unlikely(barrier))
                 req->flags |= (REQ_HARDBARRIER | REQ_NOMERGE);
 
         req->errors = 0;
@@ -2809,7 +2809,7 @@ static inline void block_wait_queue_running(request_queue_t *q)
 {
         DEFINE_WAIT(wait);
 
-        while (test_bit(QUEUE_FLAG_DRAIN, &q->queue_flags)) {
+        while (unlikely(test_bit(QUEUE_FLAG_DRAIN, &q->queue_flags))) {
                 struct request_list *rl = &q->rq;
 
                 prepare_to_wait_exclusive(&rl->drain, &wait,
@@ -2918,7 +2918,7 @@ end_io:
                         goto end_io;
                 }
 
-                if (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags))
+                if (unlikely(test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)))
                         goto end_io;
 
                 block_wait_queue_running(q);