Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: don't use spin_is_contended

fs/btrfs/ctree.c

@@ -1530,8 +1530,7 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
 			 * for higher level blocks, try not to allocate blocks
 			 * with the block and the parent locks held.
 			 */
-			if (level > 0 && !prealloc_block.objectid &&
-			    btrfs_path_lock_waiting(p, level)) {
+			if (level > 0 && !prealloc_block.objectid) {
 				u32 size = b->len;
 				u64 hint = b->start;
 

fs/btrfs/locking.c

@@ -236,25 +236,3 @@ int btrfs_tree_locked(struct extent_buffer *eb)
 	return test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags) ||
 			spin_is_locked(&eb->lock);
 }
-
-/*
- * btrfs_search_slot uses this to decide if it should drop its locks
- * before doing something expensive like allocating free blocks for cow.
- */
-int btrfs_path_lock_waiting(struct btrfs_path *path, int level)
-{
-	int i;
-	struct extent_buffer *eb;
-
-	for (i = level; i <= level + 1 && i < BTRFS_MAX_LEVEL; i++) {
-		eb = path->nodes[i];
-		if (!eb)
-			break;
-		smp_mb();
-		if (spin_is_contended(&eb->lock) ||
-		    waitqueue_active(&eb->lock_wq))
-			return 1;
-	}
-	return 0;
-}
-

fs/btrfs/locking.h

@@ -26,8 +26,6 @@ int btrfs_tree_locked(struct extent_buffer *eb);
 int btrfs_try_tree_lock(struct extent_buffer *eb);
 int btrfs_try_spin_lock(struct extent_buffer *eb);
 
-int btrfs_path_lock_waiting(struct btrfs_path *path, int level);
-
 void btrfs_set_lock_blocking(struct extent_buffer *eb);
 void btrfs_clear_lock_blocking(struct extent_buffer *eb);
 #endif