cfq-iosched: More renaming to better represent wl_class and wl_type

Some more renaming. Again making the code uniform w.r.t use of
wl_class/class to represent IO class (RT, BE, IDLE) and using
wl_type/type to represent subclass (SYNC, SYNC-IDLE, ASYNC).

At places this patch shortens the string "workload" to "wl".
Renamed "saved_workload" to "saved_wl_type". Renamed
"saved_serving_class" to "saved_wl_class".

For uniformity with "saved_wl_*" variables, renamed "serving_class"
to "serving_wl_class" and renamed "serving_type" to "serving_wl_type".

Again, just trying to improve upon code uniformity and improve
readability. No functional change.

v2:
- Restored the usage of keyword "service" based on Jeff Moyer's feedback.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 33 insertions, 31 deletions

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 7646dfddba03..8f890bfba8fd 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -248,9 +248,9 @@ struct cfq_group {
         struct cfq_rb_root service_trees[2][3];
         struct cfq_rb_root service_tree_idle;
 
-        unsigned long saved_workload_slice;
-        enum wl_type_t saved_workload;
-        enum wl_class_t saved_serving_class;
+        unsigned long saved_wl_slice;
+        enum wl_type_t saved_wl_type;
+        enum wl_class_t saved_wl_class;
 
         /* number of requests that are on the dispatch list or inside driver */
         int dispatched;
@@ -280,8 +280,8 @@ struct cfq_data {
         /*
          * The priority currently being served
          */
-        enum wl_class_t serving_class;
-        enum wl_type_t serving_type;
+        enum wl_class_t serving_wl_class;
+        enum wl_type_t serving_wl_type;
         unsigned long workload_expires;
         struct cfq_group *serving_group;
 
@@ -1241,7 +1241,7 @@ cfq_group_notify_queue_del(struct cfq_data *cfqd, struct cfq_group *cfqg)
 
         cfq_log_cfqg(cfqd, cfqg, "del_from_rr group");
         cfq_group_service_tree_del(st, cfqg);
-        cfqg->saved_workload_slice = 0;
+        cfqg->saved_wl_slice = 0;
         cfqg_stats_update_dequeue(cfqg);
 }
 
@@ -1301,12 +1301,12 @@ static void cfq_group_served(struct cfq_data *cfqd, struct cfq_group *cfqg,
 
         /* This group is being expired. Save the context */
         if (time_after(cfqd->workload_expires, jiffies)) {
-                cfqg->saved_workload_slice = cfqd->workload_expires
+                cfqg->saved_wl_slice = cfqd->workload_expires
                                                 - jiffies;
-                cfqg->saved_workload = cfqd->serving_type;
-                cfqg->saved_serving_class = cfqd->serving_class;
+                cfqg->saved_wl_type = cfqd->serving_wl_type;
+                cfqg->saved_wl_class = cfqd->serving_wl_class;
         } else
-                cfqg->saved_workload_slice = 0;
+                cfqg->saved_wl_slice = 0;
 
         cfq_log_cfqg(cfqd, cfqg, "served: vt=%llu min_vt=%llu", cfqg->vdisktime,
                                         st->min_vdisktime);
@@ -2031,7 +2031,7 @@ static void __cfq_set_active_queue(struct cfq_data *cfqd,
 {
         if (cfqq) {
                 cfq_log_cfqq(cfqd, cfqq, "set_active wl_class:%d wl_type:%d",
-                                cfqd->serving_class, cfqd->serving_type);
+                                cfqd->serving_wl_class, cfqd->serving_wl_type);
                 cfqg_stats_update_avg_queue_size(cfqq->cfqg);
                 cfqq->slice_start = 0;
                 cfqq->dispatch_start = jiffies;
@@ -2118,8 +2118,8 @@ static inline void cfq_slice_expired(struct cfq_data *cfqd, bool timed_out)
 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_class,
-                                        cfqd->serving_type);
+                service_tree_for(cfqd->serving_group, cfqd->serving_wl_class,
+                                                cfqd->serving_wl_type);
 
         if (!cfqd->rq_queued)
                 return NULL;
@@ -2523,20 +2523,20 @@ 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_class_t original_class = cfqd->serving_class;
+        enum wl_class_t original_class = cfqd->serving_wl_class;
 
         /* Choose next priority. RT > BE > IDLE */
         if (cfq_group_busy_queues_wl(RT_WORKLOAD, cfqd, cfqg))
-                cfqd->serving_class = RT_WORKLOAD;
+                cfqd->serving_wl_class = RT_WORKLOAD;
         else if (cfq_group_busy_queues_wl(BE_WORKLOAD, cfqd, cfqg))
-                cfqd->serving_class = BE_WORKLOAD;
+                cfqd->serving_wl_class = BE_WORKLOAD;
         else {
-                cfqd->serving_class = IDLE_WORKLOAD;
+                cfqd->serving_wl_class = IDLE_WORKLOAD;
                 cfqd->workload_expires = jiffies + 1;
                 return;
         }
 
-        if (original_class != cfqd->serving_class)
+        if (original_class != cfqd->serving_wl_class)
                 goto new_workload;
 
         /*
@@ -2544,7 +2544,8 @@ static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
          * (SYNC, SYNC_NOIDLE, ASYNC), and to compute a workload
          * expiration time
          */
-        st = service_tree_for(cfqg, cfqd->serving_class, cfqd->serving_type);
+        st = service_tree_for(cfqg, cfqd->serving_wl_class,
+                                        cfqd->serving_wl_type);
         count = st->count;
 
         /*
@@ -2555,9 +2556,10 @@ static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
 
 new_workload:
         /* otherwise select new workload type */
-        cfqd->serving_type =
-                cfq_choose_wl(cfqd, cfqg, cfqd->serving_class);
-        st = service_tree_for(cfqg, cfqd->serving_class, cfqd->serving_type);
+        cfqd->serving_wl_type = cfq_choose_wl(cfqd, cfqg,
+                                        cfqd->serving_wl_class);
+        st = service_tree_for(cfqg, cfqd->serving_wl_class,
+                                        cfqd->serving_wl_type);
         count = st->count;
 
         /*
@@ -2568,11 +2570,11 @@ new_workload:
         group_slice = cfq_group_slice(cfqd, cfqg);
 
         slice = group_slice * count /
-                max_t(unsigned, cfqg->busy_queues_avg[cfqd->serving_class],
-                      cfq_group_busy_queues_wl(cfqd->serving_class, cfqd,
+                max_t(unsigned, cfqg->busy_queues_avg[cfqd->serving_wl_class],
+                      cfq_group_busy_queues_wl(cfqd->serving_wl_class, cfqd,
                                         cfqg));
 
-        if (cfqd->serving_type == ASYNC_WORKLOAD) {
+        if (cfqd->serving_wl_type == ASYNC_WORKLOAD) {
                 unsigned int tmp;
 
                 /*
@@ -2618,10 +2620,10 @@ static void cfq_choose_cfqg(struct cfq_data *cfqd)
         cfqd->serving_group = cfqg;
 
         /* Restore the workload type data */
-        if (cfqg->saved_workload_slice) {
-                cfqd->workload_expires = jiffies + cfqg->saved_workload_slice;
-                cfqd->serving_type = cfqg->saved_workload;
-                cfqd->serving_class = cfqg->saved_serving_class;
+        if (cfqg->saved_wl_slice) {
+                cfqd->workload_expires = jiffies + cfqg->saved_wl_slice;
+                cfqd->serving_wl_type = cfqg->saved_wl_type;
+                cfqd->serving_wl_class = cfqg->saved_wl_class;
         } else
                 cfqd->workload_expires = jiffies - 1;
 
@@ -3404,7 +3406,7 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
                 return true;
 
         /* Allow preemption only if we are idling on sync-noidle tree */
-        if (cfqd->serving_type == SYNC_NOIDLE_WORKLOAD &&
+        if (cfqd->serving_wl_type == SYNC_NOIDLE_WORKLOAD &&
             cfqq_type(new_cfqq) == SYNC_NOIDLE_WORKLOAD &&
             new_cfqq->service_tree->count == 2 &&
             RB_EMPTY_ROOT(&cfqq->sort_list))
@@ -3456,7 +3458,7 @@ static void cfq_preempt_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq)
          * doesn't happen
          */
         if (old_type != cfqq_type(cfqq))
-                cfqq->cfqg->saved_workload_slice = 0;
+                cfqq->cfqg->saved_wl_slice = 0;
 
         /*
          * Put the new queue at the front of the of the current list,