Re: [PATCH 4/6] rbtree: faster augmented insert
From: Rik van Riel <hidden>
Date: 2012-07-25 16:15:44
Also in:
lkml
On 07/20/2012 08:31 AM, Michel Lespinasse wrote:
quoted hunk ↗ jump to hunk
+++ b/lib/rbtree.c@@ -88,7 +88,8 @@ __rb_rotate_set_parents(struct rb_node *old, struct rb_node *new, root->rb_node = new; } -void rb_insert_color(struct rb_node *node, struct rb_root *root) +inline void rb_insert_augmented(struct rb_node *node, struct rb_root *root, + rb_augment_rotate *augment) { struct rb_node *parent = rb_red_parent(node), *gparent, *tmp;@@ -152,6 +153,7 @@ void rb_insert_color(struct rb_node *node, struct rb_root *root) rb_set_parent_color(tmp, parent, RB_BLACK); rb_set_parent_color(parent, node, RB_RED); + augment(parent, node);
+static inline void dummy(struct rb_node *old, struct rb_node *new) {}
+
+void rb_insert_color(struct rb_node *node, struct rb_root *root) {
+ rb_insert_augmented(node, root, dummy);
+}
EXPORT_SYMBOL(rb_insert_color);While the above is what I would have done, the question remains "what if the compiler decides to not inline the function after all, and does not remove the call to the dummy function in rb_insert_color as a result? Do we have some way to force inlining, so the compiler is more likely to optimize out the dummy call?
quoted hunk ↗ jump to hunk
static void __rb_erase_color(struct rb_node *node, struct rb_node *parent,diff --git a/lib/rbtree_test.c b/lib/rbtree_test.c index 2dfafe4..5ace332 100644 --- a/lib/rbtree_test.c +++ b/lib/rbtree_test.c@@ -67,22 +67,37 @@ static void augment_callback(struct rb_node *rb, void *unused) node->augmented = augment_recompute(node); } +static void augment_rotate(struct rb_node *rb_old, struct rb_node *rb_new) +{ + struct test_node *old = rb_entry(rb_old, struct test_node, rb); + struct test_node *new = rb_entry(rb_new, struct test_node, rb); + + /* Rotation doesn't change subtree's augmented value */ + new->augmented = old->augmented; + old->augmented = augment_recompute(old); +}
Is it worth documenting that rb_old is always the parent of rb_new (at least, it seems to be in this patch) ? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>