author: Michel Lespinasse <walken@google.com> 2012-10-08 16:31:02 -0700
committer: Linus Torvalds <torvalds@linux-foundation.org> 2012-10-09 16:22:35 +0900
commit: 59633abf34e2f44b8e772a2c12a92132aa7c2220
parent: 7ce6ff9e5de99e7b72019c7de82fb438fe1dc5a0
Commit Summary:
Diffstat:
1 file changed, 13 insertions, 8 deletions
diff --git a/lib/rbtree.c b/lib/rbtree.c
index 08926709b4f9..61cdd0e3e538 100644
--- a/lib/rbtree.c
+++ b/lib/rbtree.c
@@ -107,8 +107,8 @@ void rb_insert_color(struct rb_node *node, struct rb_root *root)
gparent = rb_red_parent(parent);
- if (parent == gparent->rb_left) {
- tmp = gparent->rb_right;
+ tmp = gparent->rb_right;
+ if (parent != tmp) { /* parent == gparent->rb_left */
if (tmp && rb_is_red(tmp)) {
/*
* Case 1 - color flips
@@ -131,7 +131,8 @@ void rb_insert_color(struct rb_node *node, struct rb_root *root)
continue;
}
- if (parent->rb_right == node) {
+ tmp = parent->rb_right;
+ if (node == tmp) {
/*
* Case 2 - left rotate at parent
*
@@ -151,6 +152,7 @@ void rb_insert_color(struct rb_node *node, struct rb_root *root)
RB_BLACK);
rb_set_parent_color(parent, node, RB_RED);
parent = node;
+ tmp = node->rb_right;
}
/*
@@ -162,7 +164,7 @@ void rb_insert_color(struct rb_node *node, struct rb_root *root)
* / \
* n U
*/
- gparent->rb_left = tmp = parent->rb_right;
+ gparent->rb_left = tmp; /* == parent->rb_right */
parent->rb_right = gparent;
if (tmp)
rb_set_parent_color(tmp, gparent, RB_BLACK);
@@ -180,7 +182,8 @@ void rb_insert_color(struct rb_node *node, struct rb_root *root)
continue;
}
- if (parent->rb_left == node) {
+ tmp = parent->rb_left;
+ if (node == tmp) {
/* Case 2 - right rotate at parent */
parent->rb_left = tmp = node->rb_right;
node->rb_right = parent;
@@ -189,10 +192,11 @@ void rb_insert_color(struct rb_node *node, struct rb_root *root)
RB_BLACK);
rb_set_parent_color(parent, node, RB_RED);
parent = node;
+ tmp = node->rb_left;
}
/* Case 3 - left rotate at gparent */
- gparent->rb_right = tmp = parent->rb_left;
+ gparent->rb_right = tmp; /* == parent->rb_left */
parent->rb_left = gparent;
if (tmp)
rb_set_parent_color(tmp, gparent, RB_BLACK);
@@ -223,8 +227,9 @@ static void __rb_erase_color(struct rb_node *node, struct rb_node *parent,
break;
} else if (!parent) {
break;
- } else if (parent->rb_left == node) {
- sibling = parent->rb_right;
+ }
+ sibling = parent->rb_right;
+ if (node != sibling) { /* node == parent->rb_left */
if (rb_is_red(sibling)) {
/*
* Case 1 - left rotate at parent