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 <walken@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Michel Lespinasse 2012-10-08 16:31:07 -07:00 committed by Linus Torvalds
parent 28d7530928
commit 7abc704ae3

View File

@ -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)