diff mbox

[03/17] rb_tree: remove redundant if()-condition in rb_erase()

Message ID 20170531204708.10470-4-kpraveen.lkml@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Praveen Kumar May 31, 2017, 8:46 p.m. UTC 
Furthermore, notice that the initial checks:

            if (!node->rb_left)
                    child = node->rb_right;
            else if (!node->rb_right)
                    child = node->rb_left;
            else
            {
                    ...
            }
guarantee that old->rb_right is set in the final else branch, therefore
we can omit checking that again.

commit 4b324126e0c6c3a5080ca3ec0981e8766ed6f1ee from linux tree

Signed-off-by: Wolfram Strepp <wstrepp@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 xen/common/rbtree.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)
diff mbox

Patch

diff --git a/xen/common/rbtree.c b/xen/common/rbtree.c
index 3df599c3cb..0695edd9f9 100644
--- a/xen/common/rbtree.c
+++ b/xen/common/rbtree.c
@@ -256,15 +256,16 @@  void rb_erase(struct rb_node *node, struct rb_root *root)
             if (child)
                 rb_set_parent(child, parent);
             parent->rb_left = child;
+
+            node->rb_right = old->rb_right;
+            rb_set_parent(old->rb_right, node);
         }
 
         node->rb_parent_color = old->rb_parent_color;
-        node->rb_right = old->rb_right;
         node->rb_left = old->rb_left;
 
         rb_set_parent(old->rb_left, node);
-        if (old->rb_right)
-            rb_set_parent(old->rb_right, node);
+
         goto color;
     }