1 files changed, 12 insertions, 36 deletions

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index d9bfa09e68c1..8df4fe58f4e7 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -292,8 +292,7 @@ static struct cfq_group *cfq_get_next_cfqg(struct cfq_data *cfqd);
 
 static struct cfq_rb_root *service_tree_for(struct cfq_group *cfqg,
                                             enum wl_prio_t prio,
-                                            enum wl_type_t type,
-                                            struct cfq_data *cfqd)
+                                            enum wl_type_t type)
 {
         if (!cfqg)
                 return NULL;
@@ -1146,7 +1145,7 @@ static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq,
 #endif
 
         service_tree = service_tree_for(cfqq->cfqg, cfqq_prio(cfqq),
-                                                cfqq_type(cfqq), cfqd);
+                                                cfqq_type(cfqq));
         if (cfq_class_idle(cfqq)) {
                 rb_key = CFQ_IDLE_DELAY;
                 parent = rb_last(&service_tree->rb);
@@ -1609,7 +1608,7 @@ static struct cfq_queue *cfq_get_next_queue(struct cfq_data *cfqd)
 {
         struct cfq_rb_root *service_tree =
                 service_tree_for(cfqd->serving_group, cfqd->serving_prio,
-                                        cfqd->serving_type, cfqd);
+                                        cfqd->serving_type);
 
         if (!cfqd->rq_queued)
                 return NULL;
@@ -1956,8 +1955,7 @@ static void cfq_setup_merge(struct cfq_queue *cfqq, struct cfq_queue *new_cfqq)
 }
 
 static enum wl_type_t cfq_choose_wl(struct cfq_data *cfqd,
-                                struct cfq_group *cfqg, enum wl_prio_t prio,
-                                bool prio_changed)
+                                struct cfq_group *cfqg, enum wl_prio_t prio)
 {
         struct cfq_queue *queue;
         int i;
@@ -1965,24 +1963,9 @@ static enum wl_type_t cfq_choose_wl(struct cfq_data *cfqd,
         unsigned long lowest_key = 0;
         enum wl_type_t cur_best = SYNC_NOIDLE_WORKLOAD;
 
-        if (prio_changed) {
-                /*
-                 * When priorities switched, we prefer starting
-                 * from SYNC_NOIDLE (first choice), or just SYNC
-                 * over ASYNC
-                 */
-                if (service_tree_for(cfqg, prio, cur_best, cfqd)->count)
-                        return cur_best;
-                cur_best = SYNC_WORKLOAD;
-                if (service_tree_for(cfqg, prio, cur_best, cfqd)->count)
-                        return cur_best;
-
-                return ASYNC_WORKLOAD;
-        }
-
-        for (i = 0; i < 3; ++i) {
-                /* otherwise, select the one with lowest rb_key */
-                queue = cfq_rb_first(service_tree_for(cfqg, prio, i, cfqd));
+        for (i = 0; i <= SYNC_WORKLOAD; ++i) {
+                /* select the one with lowest rb_key */
+                queue = cfq_rb_first(service_tree_for(cfqg, prio, i));
                 if (queue &&
                     (!key_valid || time_before(queue->rb_key, lowest_key))) {
                         lowest_key = queue->rb_key;
@@ -1996,8 +1979,6 @@ static enum wl_type_t cfq_choose_wl(struct cfq_data *cfqd,
 
 static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
 {
-        enum wl_prio_t previous_prio = cfqd->serving_prio;
-        bool prio_changed;
         unsigned slice;
         unsigned count;
         struct cfq_rb_root *st;
@@ -2025,24 +2006,19 @@ static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
          * (SYNC, SYNC_NOIDLE, ASYNC), and to compute a workload
          * expiration time
          */
-        prio_changed = (cfqd->serving_prio != previous_prio);
-        st = service_tree_for(cfqg, cfqd->serving_prio, cfqd->serving_type,
-                                cfqd);
+        st = service_tree_for(cfqg, cfqd->serving_prio, cfqd->serving_type);
         count = st->count;
 
         /*
-         * If priority didn't change, check workload expiration,
-         * and that we still have other queues ready
+         * check workload expiration, and that we still have other queues ready
          */
-        if (!prio_changed && count &&
-            !time_after(jiffies, cfqd->workload_expires))
+        if (count && !time_after(jiffies, cfqd->workload_expires))
                 return;
 
         /* otherwise select new workload type */
         cfqd->serving_type =
-                cfq_choose_wl(cfqd, cfqg, cfqd->serving_prio, prio_changed);
-        st = service_tree_for(cfqg, cfqd->serving_prio, cfqd->serving_type,
-                                cfqd);
+                cfq_choose_wl(cfqd, cfqg, cfqd->serving_prio);
+        st = service_tree_for(cfqg, cfqd->serving_prio, cfqd->serving_type);
         count = st->count;
 
         /*