commit dd67d051529387f6e44d22d1d5540ef281965fdd
author Jens Axboe <axboe@suse.de> Wed Jun 21 09:36:18 2006 +0200
committer Jens Axboe <axboe@nelson.home.kernel.dk> Fri Jun 23 17:10:39 2006 +0200
tree 80457f9a2ad3e562b179e40f5c8d51b4f24d6d9e
parent 9e94cd4fd1812bab45237f998b3c6fa1b24023fd

[PATCH] rbtree: support functions used by the io schedulers

They all duplicate macros to check for empty root and/or node, and
clearing a node. So put those in rbtree.h.

Signed-off-by: Jens Axboe <axboe@suse.de>

block/deadline-iosched.c

diff --git a/block/deadline-iosched.c b/block/deadline-iosched.c
index e5bccaa..4469dd8 100644
--- a/block/deadline-iosched.c
+++ b/block/deadline-iosched.c
@@ -159,9 +159,6 @@
 /*
  * rb tree support functions
  */
-#define RB_EMPTY(root)	((root)->rb_node == NULL)
-#define ON_RB(node)	(rb_parent(node) != node)
-#define RB_CLEAR(node)	(rb_set_parent(node, node))
 #define rb_entry_drq(node)	rb_entry((node), struct deadline_rq, rb_node)
 #define DRQ_RB_ROOT(dd, drq)	(&(dd)->sort_list[rq_data_dir((drq)->request)])
 #define rq_rb_key(rq)		(rq)->sector
@@ -220,9 +217,9 @@
 			dd->next_drq[data_dir] = rb_entry_drq(rbnext);
 	}
 
-	BUG_ON(!ON_RB(&drq->rb_node));
+	BUG_ON(!RB_EMPTY_NODE(&drq->rb_node));
 	rb_erase(&drq->rb_node, DRQ_RB_ROOT(dd, drq));
-	RB_CLEAR(&drq->rb_node);
+	RB_CLEAR_NODE(&drq->rb_node);
 }
 
 static struct request *
@@ -496,7 +493,7 @@
 	 */
 
 	if (reads) {
-		BUG_ON(RB_EMPTY(&dd->sort_list[READ]));
+		BUG_ON(RB_EMPTY_ROOT(&dd->sort_list[READ]));
 
 		if (writes && (dd->starved++ >= dd->writes_starved))
 			goto dispatch_writes;
@@ -512,7 +509,7 @@
 
 	if (writes) {
 dispatch_writes:
-		BUG_ON(RB_EMPTY(&dd->sort_list[WRITE]));
+		BUG_ON(RB_EMPTY_ROOT(&dd->sort_list[WRITE]));
 
 		dd->starved = 0;
 
@@ -668,7 +665,7 @@
 	drq = mempool_alloc(dd->drq_pool, gfp_mask);
 	if (drq) {
 		memset(drq, 0, sizeof(*drq));
-		RB_CLEAR(&drq->rb_node);
+		RB_CLEAR_NODE(&drq->rb_node);
 		drq->request = rq;
 
 		INIT_HLIST_NODE(&drq->hash);