btrfs: remove open-coded swap() in backref.c:__merge_refs

The kernel provides a swap() that does the same thing as this code.

Signed-off-by: Dave Jones <dsj@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index b90cd37..dc6e9a3 100644 (file)
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -566,17 +566,14 @@ static void __merge_refs(struct list_head *head, int mode)
                struct __prelim_ref *pos2 = pos1, *tmp;
 
                list_for_each_entry_safe_continue(pos2, tmp, head, list) {
-                       struct __prelim_ref *xchg, *ref1 = pos1, *ref2 = pos2;
+                       struct __prelim_ref *ref1 = pos1, *ref2 = pos2;
                        struct extent_inode_elem *eie;
 
                        if (!ref_for_same_block(ref1, ref2))
                                continue;
                        if (mode == 1) {
-                               if (!ref1->parent && ref2->parent) {
-                                       xchg = ref1;
-                                       ref1 = ref2;
-                                       ref2 = xchg;
-                               }
+                               if (!ref1->parent && ref2->parent)
+                                       swap(ref1, ref2);
                        } else {
                                if (ref1->parent != ref2->parent)
                                        continue;