From a2c79a9f156a6db0c1e18d0c165d419c8e4dc2b2 Mon Sep 17 00:00:00 2001
From: Nikolay Borisov <nborisov@suse.com>
Date: Wed, 15 Aug 2018 18:26:53 +0300
Subject: [PATCH] btrfs: Remove redundant extent_buffer_get in get_old_root
[ Upstream commit 6c122e2a0c515cfb3f3a9cefb5dad4cb62109c78 ]
get_old_root used used only by btrfs_search_old_slot to initialise the
path structure. The old root is always a cloned buffer (either via alloc
dummy or via btrfs_clone_extent_buffer) and its reference count is 2: 1
from allocation, 1 from extent_buffer_get call in get_old_root.
This latter explicit ref count acquire operation is in fact unnecessary
since the semantic is such that the newly allocated buffer is handed
over to the btrfs_path for lifetime management. Considering this just
remove the extra extent_buffer_get in get_old_root.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/btrfs/ctree.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index b5ebb43b1824..78d4c8c22b4a 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -1430,7 +1430,6 @@ get_old_root(struct btrfs_root *root, u64 time_seq)
if (!eb)
return NULL;
- extent_buffer_get(eb);
btrfs_tree_read_lock(eb);
if (old_root) {
btrfs_set_header_bytenr(eb, eb->start);
--
2.30.9