From e52784c445e2607147c6c5b44e5a508eecebdfe3 Mon Sep 17 00:00:00 2001 From: Michel Lespinasse Date: Wed, 26 Sep 2012 11:33:34 +1000 Subject: [PATCH] rbtree: add __rb_change_child() helper function Add __rb_change_child() as an inline helper function to replace code that would otherwise be duplicated 4 times in the source. No changes to binary size or speed. Signed-off-by: Michel Lespinasse Reviewed-by: Rik van Riel Cc: Peter Zijlstra Cc: Andrea Arcangeli Cc: David Woodhouse Signed-off-by: Andrew Morton --- lib/rbtree.c | 46 +++++++++++++++++----------------------------- 1 file changed, 17 insertions(+), 29 deletions(-) diff --git a/lib/rbtree.c b/lib/rbtree.c index 61cdd0e3e538..de89a614b1ba 100644 --- a/lib/rbtree.c +++ b/lib/rbtree.c @@ -66,6 +66,19 @@ static inline struct rb_node *rb_red_parent(struct rb_node *red) return (struct rb_node *)red->__rb_parent_color; } +static inline void +__rb_change_child(struct rb_node *old, struct rb_node *new, + struct rb_node *parent, struct rb_root *root) +{ + if (parent) { + if (parent->rb_left == old) + parent->rb_left = new; + else + parent->rb_right = new; + } else + root->rb_node = new; +} + /* * Helper function for rotations: * - old's parent and color get assigned to new @@ -78,13 +91,7 @@ __rb_rotate_set_parents(struct rb_node *old, struct rb_node *new, struct rb_node *parent = rb_parent(old); new->__rb_parent_color = old->__rb_parent_color; rb_set_parent_color(old, new, color); - if (parent) { - if (parent->rb_left == old) - parent->rb_left = new; - else - parent->rb_right = new; - } else - root->rb_node = new; + __rb_change_child(old, new, parent, root); } void rb_insert_color(struct rb_node *node, struct rb_root *root) @@ -375,13 +382,7 @@ void rb_erase(struct rb_node *node, struct rb_root *root) while ((left = node->rb_left) != NULL) node = left; - if (rb_parent(old)) { - if (rb_parent(old)->rb_left == old) - rb_parent(old)->rb_left = node; - else - rb_parent(old)->rb_right = node; - } else - root->rb_node = node; + __rb_change_child(old, node, rb_parent(old), root); child = node->rb_right; parent = rb_parent(node); @@ -410,13 +411,7 @@ void rb_erase(struct rb_node *node, struct rb_root *root) if (child) rb_set_parent(child, parent); - if (parent) { - if (parent->rb_left == node) - parent->rb_left = child; - else - parent->rb_right = child; - } else - root->rb_node = child; + __rb_change_child(node, child, parent, root); color: if (color == RB_BLACK) @@ -591,14 +586,7 @@ void rb_replace_node(struct rb_node *victim, struct rb_node *new, struct rb_node *parent = rb_parent(victim); /* Set the surrounding nodes to point to the replacement */ - if (parent) { - if (victim == parent->rb_left) - parent->rb_left = new; - else - parent->rb_right = new; - } else { - root->rb_node = new; - } + __rb_change_child(victim, new, parent, root); if (victim->rb_left) rb_set_parent(victim->rb_left, new); if (victim->rb_right) -- 2.39.5