[PATCH] 04/05 remove last_merge handling from ioscheds

Remove last_merge handling from all ioscheds.  This patch
removes merging capability of noop iosched.

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

1 files changed, 2 insertions, 28 deletions

diff --git a/drivers/block/deadline-iosched.c b/drivers/block/deadline-iosched.c
index 07de4d24ddba..43d93155efb8 100644
--- a/drivers/block/deadline-iosched.c
+++ b/drivers/block/deadline-iosched.c
@@ -112,15 +112,6 @@ static inline void deadline_del_drq_hash(struct deadline_rq *drq)
                 __deadline_del_drq_hash(drq);
 }
 
-static void
-deadline_remove_merge_hints(request_queue_t *q, struct deadline_rq *drq)
-{
-        deadline_del_drq_hash(drq);
-
-        if (q->last_merge == drq->request)
-                q->last_merge = NULL;
-}
-
 static inline void
 deadline_add_drq_hash(struct deadline_data *dd, struct deadline_rq *drq)
 {
@@ -299,12 +290,8 @@ deadline_add_request(struct request_queue *q, struct request *rq)
         drq->expires = jiffies + dd->fifo_expire[data_dir];
         list_add_tail(&drq->fifo, &dd->fifo_list[data_dir]);
 
-        if (rq_mergeable(rq)) {
+        if (rq_mergeable(rq))
                 deadline_add_drq_hash(dd, drq);
-
-                if (!q->last_merge)
-                        q->last_merge = rq;
-        }
 }
 
 /*
@@ -316,8 +303,8 @@ static void deadline_remove_request(request_queue_t *q, struct request *rq)
         struct deadline_data *dd = q->elevator->elevator_data;
 
         list_del_init(&drq->fifo);
-        deadline_remove_merge_hints(q, drq);
         deadline_del_drq_rb(dd, drq);
+        deadline_del_drq_hash(drq);
 }
 
 static int
@@ -328,15 +315,6 @@ deadline_merge(request_queue_t *q, struct request **req, struct bio *bio)
         int ret;
 
         /*
-         * try last_merge to avoid going to hash
-         */
-        ret = elv_try_last_merge(q, bio);
-        if (ret != ELEVATOR_NO_MERGE) {
-                __rq = q->last_merge;
-                goto out_insert;
-        }
-
-        /*
          * see if the merge hash can satisfy a back merge
          */
         __rq = deadline_find_drq_hash(dd, bio->bi_sector);
@@ -368,8 +346,6 @@ deadline_merge(request_queue_t *q, struct request **req, struct bio *bio)
 
         return ELEVATOR_NO_MERGE;
 out:
-        q->last_merge = __rq;
-out_insert:
         if (ret)
                 deadline_hot_drq_hash(dd, RQ_DATA(__rq));
         *req = __rq;
@@ -394,8 +370,6 @@ static void deadline_merged_request(request_queue_t *q, struct request *req)
                 deadline_del_drq_rb(dd, drq);
                 deadline_add_drq_rb(dd, drq);
         }
-
-        q->last_merge = req;
 }
 
 static void