1 files changed, 30 insertions, 26 deletions

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 4cd59b0d7c15..9b186fd6bf47 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -87,7 +87,6 @@ struct cfq_rb_root {
         unsigned count;
         unsigned total_weight;
         u64 min_vdisktime;
-        struct rb_node *active;
 };
 #define CFQ_RB_ROOT     (struct cfq_rb_root) { .rb = RB_ROOT, .left = NULL, \
                         .count = 0, .min_vdisktime = 0, }
@@ -180,7 +179,6 @@ struct cfq_group {
         /* group service_tree key */
         u64 vdisktime;
         unsigned int weight;
-        bool on_st;
 
         /* number of cfqq currently on this group */
         int nr_cfqq;
@@ -563,11 +561,6 @@ static void update_min_vdisktime(struct cfq_rb_root *st)
         u64 vdisktime = st->min_vdisktime;
         struct cfq_group *cfqg;
 
-        if (st->active) {
-                cfqg = rb_entry_cfqg(st->active);
-                vdisktime = cfqg->vdisktime;
-        }
-
         if (st->left) {
                 cfqg = rb_entry_cfqg(st->left);
                 vdisktime = min_vdisktime(vdisktime, cfqg->vdisktime);
@@ -646,11 +639,11 @@ cfq_set_prio_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq)
 static inline bool cfq_slice_used(struct cfq_queue *cfqq)
 {
         if (cfq_cfqq_slice_new(cfqq))
-                return 0;
+                return false;
         if (time_before(jiffies, cfqq->slice_end))
-                return 0;
+                return false;
 
-        return 1;
+        return true;
 }
 
 /*
@@ -869,7 +862,7 @@ cfq_group_service_tree_add(struct cfq_data *cfqd, struct cfq_group *cfqg)
         struct rb_node *n;
 
         cfqg->nr_cfqq++;
-        if (cfqg->on_st)
+        if (!RB_EMPTY_NODE(&cfqg->rb_node))
                 return;
 
         /*
@@ -885,7 +878,6 @@ cfq_group_service_tree_add(struct cfq_data *cfqd, struct cfq_group *cfqg)
                 cfqg->vdisktime = st->min_vdisktime;
 
         __cfq_group_service_tree_add(st, cfqg);
-        cfqg->on_st = true;
         st->total_weight += cfqg->weight;
 }
 
@@ -894,9 +886,6 @@ cfq_group_service_tree_del(struct cfq_data *cfqd, struct cfq_group *cfqg)
 {
         struct cfq_rb_root *st = &cfqd->grp_service_tree;
 
-        if (st->active == &cfqg->rb_node)
-                st->active = NULL;
-
         BUG_ON(cfqg->nr_cfqq < 1);
         cfqg->nr_cfqq--;
 
@@ -905,7 +894,6 @@ cfq_group_service_tree_del(struct cfq_data *cfqd, struct cfq_group *cfqg)
                 return;
 
         cfq_log_cfqg(cfqd, cfqg, "del_from_rr group");
-        cfqg->on_st = false;
         st->total_weight -= cfqg->weight;
         if (!RB_EMPTY_NODE(&cfqg->rb_node))
                 cfq_rb_erase(&cfqg->rb_node, st);
@@ -1095,7 +1083,7 @@ static void cfq_put_cfqg(struct cfq_group *cfqg)
         if (!atomic_dec_and_test(&cfqg->ref))
                 return;
         for_each_cfqg_st(cfqg, i, j, st)
-                BUG_ON(!RB_EMPTY_ROOT(&st->rb) || st->active != NULL);
+                BUG_ON(!RB_EMPTY_ROOT(&st->rb));
         kfree(cfqg);
 }
 
@@ -1687,9 +1675,6 @@ __cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq,
         if (cfqq == cfqd->active_queue)
                 cfqd->active_queue = NULL;
 
-        if (&cfqq->cfqg->rb_node == cfqd->grp_service_tree.active)
-                cfqd->grp_service_tree.active = NULL;
-
         if (cfqd->active_cic) {
                 put_io_context(cfqd->active_cic->ioc);
                 cfqd->active_cic = NULL;
@@ -1901,10 +1886,10 @@ static bool cfq_should_idle(struct cfq_data *cfqd, struct cfq_queue *cfqq)
          * in their service tree.
          */
         if (service_tree->count == 1 && cfq_cfqq_sync(cfqq))
-                return 1;
+                return true;
         cfq_log_cfqq(cfqd, cfqq, "Not idling. st->count:%d",
                         service_tree->count);
-        return 0;
+        return false;
 }
 
 static void cfq_arm_slice_timer(struct cfq_data *cfqd)
@@ -2116,6 +2101,7 @@ static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
         unsigned count;
         struct cfq_rb_root *st;
         unsigned group_slice;
+        enum wl_prio_t original_prio = cfqd->serving_prio;
 
         if (!cfqg) {
                 cfqd->serving_prio = IDLE_WORKLOAD;
@@ -2134,6 +2120,9 @@ static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
                 return;
         }
 
+        if (original_prio != cfqd->serving_prio)
+                goto new_workload;
+
         /*
          * For RT and BE, we have to choose also the type
          * (SYNC, SYNC_NOIDLE, ASYNC), and to compute a workload
@@ -2148,6 +2137,7 @@ static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
         if (count && !time_after(jiffies, cfqd->workload_expires))
                 return;
 
+new_workload:
         /* otherwise select new workload type */
         cfqd->serving_type =
                 cfq_choose_wl(cfqd, cfqg, cfqd->serving_prio);
@@ -2199,7 +2189,6 @@ static struct cfq_group *cfq_get_next_cfqg(struct cfq_data *cfqd)
         if (RB_EMPTY_ROOT(&st->rb))
                 return NULL;
         cfqg = cfq_rb_first_group(st);
-        st->active = &cfqg->rb_node;
         update_min_vdisktime(st);
         return cfqg;
 }
@@ -2293,6 +2282,17 @@ static struct cfq_queue *cfq_select_queue(struct cfq_data *cfqd)
                 goto keep_queue;
         }
 
+        /*
+         * This is a deep seek queue, but the device is much faster than
+         * the queue can deliver, don't idle
+         **/
+        if (CFQQ_SEEKY(cfqq) && cfq_cfqq_idle_window(cfqq) &&
+            (cfq_cfqq_slice_new(cfqq) ||
+            (cfqq->slice_end - jiffies > jiffies - cfqq->slice_start))) {
+                cfq_clear_cfqq_deep(cfqq);
+                cfq_clear_cfqq_idle_window(cfqq);
+        }
+
         if (cfqq->dispatched && cfq_should_idle(cfqd, cfqq)) {
                 cfqq = NULL;
                 goto keep_queue;
@@ -2367,12 +2367,12 @@ static inline bool cfq_slice_used_soon(struct cfq_data *cfqd,
 {
         /* the queue hasn't finished any request, can't estimate */
         if (cfq_cfqq_slice_new(cfqq))
-                return 1;
+                return true;
         if (time_after(jiffies + cfqd->cfq_slice_idle * cfqq->dispatched,
                 cfqq->slice_end))
-                return 1;
+                return true;
 
-        return 0;
+        return false;
 }
 
 static bool cfq_may_dispatch(struct cfq_data *cfqd, struct cfq_queue *cfqq)
@@ -3265,6 +3265,10 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
         if (cfq_class_rt(new_cfqq) && !cfq_class_rt(cfqq))
                 return true;
 
+        /* An idle queue should not be idle now for some reason */
+        if (RB_EMPTY_ROOT(&cfqq->sort_list) && !cfq_should_idle(cfqd, cfqq))
+                return true;
+
         if (!cfqd->active_cic || !cfq_cfqq_wait_request(cfqq))
                 return false;