Btrfs: send, avoid unnecessary inode item lookup in the btree

Regardless of whether the caller is interested or not in knowing the inode's
generation (dir_gen != NULL), get_first_ref always does a btree lookup to get
the inode item. Avoid this useless lookup if dir_gen parameter is NULL (which
is in some cases).

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
This commit is contained in:
Filipe Manana 2014-03-21 12:46:54 +00:00 committed by Chris Mason
parent 23f8f9b7ca
commit b46ab97bcd

View file

@ -1693,10 +1693,12 @@ static int get_first_ref(struct btrfs_root *root, u64 ino,
goto out;
btrfs_release_path(path);
ret = get_inode_info(root, parent_dir, NULL, dir_gen, NULL, NULL,
NULL, NULL);
if (ret < 0)
goto out;
if (dir_gen) {
ret = get_inode_info(root, parent_dir, NULL, dir_gen, NULL,
NULL, NULL, NULL);
if (ret < 0)
goto out;
}
*dir = parent_dir;
@ -1712,13 +1714,12 @@ static int is_first_ref(struct btrfs_root *root,
int ret;
struct fs_path *tmp_name;
u64 tmp_dir;
u64 tmp_dir_gen;
tmp_name = fs_path_alloc();
if (!tmp_name)
return -ENOMEM;
ret = get_first_ref(root, ino, &tmp_dir, &tmp_dir_gen, tmp_name);
ret = get_first_ref(root, ino, &tmp_dir, NULL, tmp_name);
if (ret < 0)
goto out;