File btrfs-progs-remove-useless-branch-in-_merge_refs.patch of Package btrfsprogs.5036

From: Su Yue <suy.fnst@cn.fujitsu.com>
Subject: btrfs-progs: remove useless branch in __merge_refs
Git-commit: d9b32dd2e9cfd5df62ceb76e939b4a76d1229e94
Patch-mainline: v4.17
References: bsc#1125340

After call of ref_for_same_block, ref1->parent must equals to
ref2->parent, the block of exchange is never reached.

So remove the block of exchange.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Acked-by: Jeff Mahoney <jeffm@suse.com>
---
 backref.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/backref.c b/backref.c
index c144dbf0..51553c70 100644
--- a/backref.c
+++ b/backref.c
@@ -497,7 +497,6 @@ static void __merge_refs(struct pref_state *prefstate, int mode)
 		for (pos2 = pos1->next, n2 = pos2->next; pos2 != head;
 		     pos2 = n2, n2 = pos2->next) {
 			struct __prelim_ref *ref2;
-			struct __prelim_ref *xchg;
 			struct extent_inode_elem *eie;
 
 			ref2 = list_entry(pos2, struct __prelim_ref, list);
@@ -505,11 +504,6 @@ static void __merge_refs(struct pref_state *prefstate, int mode)
 			if (mode == 1) {
 				if (!ref_for_same_block(ref1, ref2))
 					continue;
-				if (!ref1->parent && ref2->parent) {
-					xchg = ref1;
-					ref1 = ref2;
-					ref2 = xchg;
-				}
 			} else {
 				if (ref1->parent != ref2->parent)
 					continue;