From: Liu Bo <bo.liu@linux.alibaba.com>
Date: Wed, 12 Sep 2018 06:06:23 +0800
Patch-mainline: 4.20
Git-commit: 98e6b1eb4022f2eb9845f0da5f16c179e5f32b9f
Subject: [PATCH 10/11] Btrfs: remove unnecessary level check in balance_level
References: bsc#1126802

In the callchain:

btrfs_search_slot()
   if (level != 0)
      setup_nodes_for_search()
          balance_level()

It is just impossible to have level=0 in balance_level, we can drop the
check.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/ctree.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index cc01890970a8..67201177ffac 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -1919,8 +1919,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 	int orig_slot = path->slots[level];
 	u64 orig_ptr;
 
-	if (level == 0)
-		return 0;
+	ASSERT(level > 0);
 
 	mid = path->nodes[level];
 
-- 
2.19.0