block: Update to io-controller stats

Changelog from v1:
o Call blkiocg_update_idle_time_stats() at cfq_rq_enqueued() instead of at
  dispatch time.

Changelog from original patchset: (in response to Vivek Goyal's comments)
o group blkiocg_update_blkio_group_dequeue_stats() with other DEBUG functions
o rename blkiocg_update_set_active_queue_stats() to
  blkiocg_update_avg_queue_size_stats()
o s/request/io/ in blkiocg_update_request_add_stats() and
  blkiocg_update_request_remove_stats()
o Call cfq_del_timer() at request dispatch() instead of
  blkiocg_update_idle_time_stats()

Signed-off-by: Divyesh Shah<dpshah@google.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 3c27bdf..1d409ad 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -169,7 +169,7 @@
 {
 	return blkg->path;
 }
-void blkiocg_update_set_active_queue_stats(struct blkio_group *blkg);
+void blkiocg_update_avg_queue_size_stats(struct blkio_group *blkg);
 void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
 				unsigned long dequeue);
 void blkiocg_update_set_idle_time_stats(struct blkio_group *blkg);
@@ -198,7 +198,7 @@
 #undef BLKG_FLAG_FNS
 #else
 static inline char *blkg_path(struct blkio_group *blkg) { return NULL; }
-static inline void blkiocg_update_set_active_queue_stats(
+static inline void blkiocg_update_avg_queue_size_stats(
 						struct blkio_group *blkg) {}
 static inline void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
 						unsigned long dequeue) {}
@@ -226,9 +226,9 @@
 	uint64_t start_time, uint64_t io_start_time, bool direction, bool sync);
 void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction,
 					bool sync);
-void blkiocg_update_request_add_stats(struct blkio_group *blkg,
+void blkiocg_update_io_add_stats(struct blkio_group *blkg,
 		struct blkio_group *curr_blkg, bool direction, bool sync);
-void blkiocg_update_request_remove_stats(struct blkio_group *blkg,
+void blkiocg_update_io_remove_stats(struct blkio_group *blkg,
 					bool direction, bool sync);
 #else
 struct cgroup;
@@ -253,9 +253,9 @@
 		bool sync) {}
 static inline void blkiocg_update_io_merged_stats(struct blkio_group *blkg,
 						bool direction, bool sync) {}
-static inline void blkiocg_update_request_add_stats(struct blkio_group *blkg,
+static inline void blkiocg_update_io_add_stats(struct blkio_group *blkg,
 		struct blkio_group *curr_blkg, bool direction, bool sync) {}
-static inline void blkiocg_update_request_remove_stats(struct blkio_group *blkg,
+static inline void blkiocg_update_io_remove_stats(struct blkio_group *blkg,
 						bool direction, bool sync) {}
 #endif
 #endif /* _BLK_CGROUP_H */