Re: [PATCH Linux 2.6.12-rc6-mm1 05/06] blk: remove last_merge handling from noop iosched

[Tejun Heo <htejun@gmail.com>]

05_blk_last_merge_consolidation_noop.patch

	Remove last_merge handling from noop iosched.  This change
	removes merging capability of noop iosched.

Signed-off-by: Tejun Heo <htejun@gmail.com>

 noop-iosched.c |   31 -------------------------------
 1 files changed, 31 deletions(-)

Index: blk-fixes/drivers/block/noop-iosched.c
===================================================================
--- blk-fixes.orig/drivers/block/noop-iosched.c	2005-06-16 13:55:38.000000000 +0900
+++ blk-fixes/drivers/block/noop-iosched.c	2005-06-16 13:55:38.000000000 +0900
@@ -7,38 +7,9 @@
 #include <linux/module.h>
 #include <linux/init.h>
 
-/*
- * See if we can find a request that this buffer can be coalesced with.
- */
-static int elevator_noop_merge(request_queue_t *q, struct request **req,
-			       struct bio *bio)
-{
-	int ret;
-
-	ret = elv_try_last_merge(q, bio);
-	if (ret != ELEVATOR_NO_MERGE)
-		*req = q->last_merge;
-
-	return ret;
-}
-
-static void elevator_noop_merge_requests(request_queue_t *q, struct request *req,
-					 struct request *next)
-{
-	list_del_init(&next->queuelist);
-}
-
 static void elevator_noop_add_request(request_queue_t *q, struct request *rq)
 {
 	elv_dispatch_insert(q, rq, 0);
-
-	/*
-	 * new merges must not precede this barrier
-	 */
-	if (rq->flags & REQ_HARDBARRIER)
-		q->last_merge = NULL;
-	else if (!q->last_merge)
-		q->last_merge = rq;
 }
 
 static int elevator_noop_dispatch(request_queue_t *q, int force)
@@ -48,8 +19,6 @@ static int elevator_noop_dispatch(reques
 
 static struct elevator_type elevator_noop = {
 	.ops = {
-		.elevator_merge_fn		= elevator_noop_merge,
-		.elevator_merge_req_fn		= elevator_noop_merge_requests,
 		.elevator_dispatch_fn		= elevator_noop_dispatch,
 		.elevator_add_req_fn		= elevator_noop_add_request,
 	},