blk-cgroup: Add unaccounted time to timeslice_used.

There are two kind of times that tasks are not charged for: the first
seek and the extra time slice used over the allocated timeslice. Both
of these exported as a new unaccounted_time stat.

I think it would be good to have this reported in 'time' as well, but
that is probably a separate discussion.

Signed-off-by: Justin TerAvest <teravest@google.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

1 files changed, 10 insertions, 2 deletions

diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 57e7234c5ae5..10919fae2d3a 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -49,6 +49,8 @@ enum stat_type {
         /* All the single valued stats go below this */
         BLKIO_STAT_TIME,
         BLKIO_STAT_SECTORS,
+        /* Time not charged to this cgroup */
+        BLKIO_STAT_UNACCOUNTED_TIME,
 #ifdef CONFIG_DEBUG_BLK_CGROUP
         BLKIO_STAT_AVG_QUEUE_SIZE,
         BLKIO_STAT_IDLE_TIME,
@@ -81,6 +83,7 @@ enum blkcg_file_name_prop {
         BLKIO_PROP_io_serviced,
         BLKIO_PROP_time,
         BLKIO_PROP_sectors,
+        BLKIO_PROP_unaccounted_time,
         BLKIO_PROP_io_service_time,
         BLKIO_PROP_io_wait_time,
         BLKIO_PROP_io_merged,
@@ -114,6 +117,8 @@ struct blkio_group_stats {
         /* total disk time and nr sectors dispatched by this group */
         uint64_t time;
         uint64_t sectors;
+        /* Time not charged to this cgroup */
+        uint64_t unaccounted_time;
         uint64_t stat_arr[BLKIO_STAT_QUEUED + 1][BLKIO_STAT_TOTAL];
 #ifdef CONFIG_DEBUG_BLK_CGROUP
         /* Sum of number of IOs queued across all samples */
@@ -293,7 +298,8 @@ extern int blkiocg_del_blkio_group(struct blkio_group *blkg);
 extern struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg,
                                                 void *key);
 void blkiocg_update_timeslice_used(struct blkio_group *blkg,
-                                        unsigned long time);
+                                        unsigned long time,
+                                        unsigned long unaccounted_time);
 void blkiocg_update_dispatch_stats(struct blkio_group *blkg, uint64_t bytes,
                                                 bool direction, bool sync);
 void blkiocg_update_completion_stats(struct blkio_group *blkg,
@@ -319,7 +325,9 @@ blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; }
 static inline struct blkio_group *
 blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key) { return NULL; }
 static inline void blkiocg_update_timeslice_used(struct blkio_group *blkg,
-                                                unsigned long time) {}
+                                                unsigned long time,
+                                                unsigned long unaccounted_time)
+{}
 static inline void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
                                 uint64_t bytes, bool direction, bool sync) {}
 static inline void blkiocg_update_completion_stats(struct blkio_group *blkg,