]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/commitdiff
blkcg: move blkio_group_stats to cfq-iosched.c
authorTejun Heo <tj@kernel.org>
Sun, 1 Apr 2012 21:38:44 +0000 (14:38 -0700)
committerTejun Heo <tj@kernel.org>
Sun, 1 Apr 2012 21:38:44 +0000 (14:38 -0700)
blkio_group_stats contains only fields used by cfq and has no reason
to be defined in blkcg core.

* Move blkio_group_stats to cfq-iosched.c and rename it to cfqg_stats.

* blkg_policy_data->stats is replaced with cfq_group->stats.
  blkg_prfill_[rw]stat() are updated to use offset against pd->pdata
  instead.

* All related macros / functions are renamed so that they have cfqg_
  prefix and the unnecessary @pol arguments are dropped.

* All stat functions now take cfq_group * instead of blkio_group *.

* lockdep assertion on queue lock dropped.  Elevator runs under queue
  lock by default.  There isn't much to be gained by adding lockdep
  assertions at stat function level.

* cfqg_stats_reset() implemented for blkio_reset_group_stats_fn method
  so that cfqg->stats can be reset.

Signed-off-by: Tejun Heo <tj@kernel.org>
block/blk-cgroup.c
block/blk-cgroup.h
block/cfq-iosched.c

index 2e6fb7d918050510ed18b62613b940acece55733..cfdda44f4a0b6cbcef1b85508e241f36cec664ab 100644 (file)
@@ -417,25 +417,6 @@ blkiocg_reset_stats(struct cgroup *cgroup, struct cftype *cftype, u64 val)
                struct blkio_policy_type *pol;
 
                list_for_each_entry(pol, &blkio_list, list) {
-                       struct blkg_policy_data *pd = blkg->pd[pol->plid];
-                       struct blkio_group_stats *stats = &pd->stats;
-
-                       /* queued stats shouldn't be cleared */
-                       blkg_rwstat_reset(&stats->service_bytes);
-                       blkg_rwstat_reset(&stats->serviced);
-                       blkg_rwstat_reset(&stats->merged);
-                       blkg_rwstat_reset(&stats->service_time);
-                       blkg_rwstat_reset(&stats->wait_time);
-                       blkg_stat_reset(&stats->time);
-#ifdef CONFIG_DEBUG_BLK_CGROUP
-                       blkg_stat_reset(&stats->unaccounted_time);
-                       blkg_stat_reset(&stats->avg_queue_size_sum);
-                       blkg_stat_reset(&stats->avg_queue_size_samples);
-                       blkg_stat_reset(&stats->dequeue);
-                       blkg_stat_reset(&stats->group_wait_time);
-                       blkg_stat_reset(&stats->idle_time);
-                       blkg_stat_reset(&stats->empty_time);
-#endif
                        blkio_reset_stats_cpu(blkg, pol->plid);
 
                        if (pol->ops.blkio_reset_group_stats_fn)
@@ -549,13 +530,13 @@ static u64 blkg_prfill_stat(struct seq_file *sf, struct blkg_policy_data *pd,
                            int off)
 {
        return __blkg_prfill_u64(sf, pd,
-                                blkg_stat_read((void *)&pd->stats + off));
+                                blkg_stat_read((void *)pd->pdata + off));
 }
 
 static u64 blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
                              int off)
 {
-       struct blkg_rwstat rwstat = blkg_rwstat_read((void *)&pd->stats + off);
+       struct blkg_rwstat rwstat = blkg_rwstat_read((void *)pd->pdata + off);
 
        return __blkg_prfill_rwstat(sf, pd, &rwstat);
 }
index d0ee649e8bbb72758fc66f67a2185c23ae511ba1..791570394e871115b27e867089589360def33f43 100644 (file)
@@ -64,46 +64,6 @@ struct blkg_rwstat {
        uint64_t                        cnt[BLKG_RWSTAT_NR];
 };
 
-struct blkio_group_stats {
-       /* total bytes transferred */
-       struct blkg_rwstat              service_bytes;
-       /* total IOs serviced, post merge */
-       struct blkg_rwstat              serviced;
-       /* number of ios merged */
-       struct blkg_rwstat              merged;
-       /* total time spent on device in ns, may not be accurate w/ queueing */
-       struct blkg_rwstat              service_time;
-       /* total time spent waiting in scheduler queue in ns */
-       struct blkg_rwstat              wait_time;
-       /* number of IOs queued up */
-       struct blkg_rwstat              queued;
-       /* total sectors transferred */
-       struct blkg_stat                sectors;
-       /* total disk time and nr sectors dispatched by this group */
-       struct blkg_stat                time;
-#ifdef CONFIG_DEBUG_BLK_CGROUP
-       /* time not charged to this cgroup */
-       struct blkg_stat                unaccounted_time;
-       /* sum of number of ios queued across all samples */
-       struct blkg_stat                avg_queue_size_sum;
-       /* count of samples taken for average */
-       struct blkg_stat                avg_queue_size_samples;
-       /* how many times this group has been removed from service tree */
-       struct blkg_stat                dequeue;
-       /* total time spent waiting for it to be assigned a timeslice. */
-       struct blkg_stat                group_wait_time;
-       /* time spent idling for this blkio_group */
-       struct blkg_stat                idle_time;
-       /* total time with empty current active q with other requests queued */
-       struct blkg_stat                empty_time;
-       /* fields after this shouldn't be cleared on stat reset */
-       uint64_t                        start_group_wait_time;
-       uint64_t                        start_idle_time;
-       uint64_t                        start_empty_time;
-       uint16_t                        flags;
-#endif
-};
-
 /* Per cpu blkio group stats */
 struct blkio_group_stats_cpu {
        /* total bytes transferred */
@@ -126,7 +86,6 @@ struct blkg_policy_data {
        /* Configuration */
        struct blkio_group_conf conf;
 
-       struct blkio_group_stats stats;
        /* Per cpu stats pointer */
        struct blkio_group_stats_cpu __percpu *stats_cpu;
 
index effd894895061d8a2489bbb3901000f8904e923d..a1f37dfd1b8b64dc9505493059c9282b50131215 100644 (file)
@@ -173,6 +173,48 @@ enum wl_type_t {
        SYNC_WORKLOAD = 2
 };
 
+struct cfqg_stats {
+#ifdef CONFIG_CFQ_GROUP_IOSCHED
+       /* total bytes transferred */
+       struct blkg_rwstat              service_bytes;
+       /* total IOs serviced, post merge */
+       struct blkg_rwstat              serviced;
+       /* number of ios merged */
+       struct blkg_rwstat              merged;
+       /* total time spent on device in ns, may not be accurate w/ queueing */
+       struct blkg_rwstat              service_time;
+       /* total time spent waiting in scheduler queue in ns */
+       struct blkg_rwstat              wait_time;
+       /* number of IOs queued up */
+       struct blkg_rwstat              queued;
+       /* total sectors transferred */
+       struct blkg_stat                sectors;
+       /* total disk time and nr sectors dispatched by this group */
+       struct blkg_stat                time;
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+       /* time not charged to this cgroup */
+       struct blkg_stat                unaccounted_time;
+       /* sum of number of ios queued across all samples */
+       struct blkg_stat                avg_queue_size_sum;
+       /* count of samples taken for average */
+       struct blkg_stat                avg_queue_size_samples;
+       /* how many times this group has been removed from service tree */
+       struct blkg_stat                dequeue;
+       /* total time spent waiting for it to be assigned a timeslice. */
+       struct blkg_stat                group_wait_time;
+       /* time spent idling for this blkio_group */
+       struct blkg_stat                idle_time;
+       /* total time with empty current active q with other requests queued */
+       struct blkg_stat                empty_time;
+       /* fields after this shouldn't be cleared on stat reset */
+       uint64_t                        start_group_wait_time;
+       uint64_t                        start_idle_time;
+       uint64_t                        start_empty_time;
+       uint16_t                        flags;
+#endif /* CONFIG_DEBUG_BLK_CGROUP */
+#endif /* CONFIG_CFQ_GROUP_IOSCHED */
+};
+
 /* This is per cgroup per device grouping structure */
 struct cfq_group {
        /* group service_tree member */
@@ -212,6 +254,7 @@ struct cfq_group {
        /* number of requests that are on the dispatch list or inside driver */
        int dispatched;
        struct cfq_ttime ttime;
+       struct cfqg_stats stats;
 };
 
 struct cfq_io_cq {
@@ -368,96 +411,84 @@ CFQ_CFQQ_FNS(wait_busy);
 
 #if defined(CONFIG_CFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP)
 
-/* blkg state flags */
-enum blkg_state_flags {
-       BLKG_waiting = 0,
-       BLKG_idling,
-       BLKG_empty,
+/* cfqg stats flags */
+enum cfqg_stats_flags {
+       CFQG_stats_waiting = 0,
+       CFQG_stats_idling,
+       CFQG_stats_empty,
 };
 
-#define BLKG_FLAG_FNS(name)                                            \
-static inline void blkio_mark_blkg_##name(                             \
-               struct blkio_group_stats *stats)                        \
+#define CFQG_FLAG_FNS(name)                                            \
+static inline void cfqg_stats_mark_##name(struct cfqg_stats *stats)    \
 {                                                                      \
-       stats->flags |= (1 << BLKG_##name);                             \
+       stats->flags |= (1 << CFQG_stats_##name);                       \
 }                                                                      \
-static inline void blkio_clear_blkg_##name(                            \
-               struct blkio_group_stats *stats)                        \
+static inline void cfqg_stats_clear_##name(struct cfqg_stats *stats)   \
 {                                                                      \
-       stats->flags &= ~(1 << BLKG_##name);                            \
+       stats->flags &= ~(1 << CFQG_stats_##name);                      \
 }                                                                      \
-static inline int blkio_blkg_##name(struct blkio_group_stats *stats)   \
+static inline int cfqg_stats_##name(struct cfqg_stats *stats)          \
 {                                                                      \
-       return (stats->flags & (1 << BLKG_##name)) != 0;                \
+       return (stats->flags & (1 << CFQG_stats_##name)) != 0;          \
 }                                                                      \
 
-BLKG_FLAG_FNS(waiting)
-BLKG_FLAG_FNS(idling)
-BLKG_FLAG_FNS(empty)
-#undef BLKG_FLAG_FNS
+CFQG_FLAG_FNS(waiting)
+CFQG_FLAG_FNS(idling)
+CFQG_FLAG_FNS(empty)
+#undef CFQG_FLAG_FNS
 
 /* This should be called with the queue_lock held. */
-static void blkio_update_group_wait_time(struct blkio_group_stats *stats)
+static void cfqg_stats_update_group_wait_time(struct cfqg_stats *stats)
 {
        unsigned long long now;
 
-       if (!blkio_blkg_waiting(stats))
+       if (!cfqg_stats_waiting(stats))
                return;
 
        now = sched_clock();
        if (time_after64(now, stats->start_group_wait_time))
                blkg_stat_add(&stats->group_wait_time,
                              now - stats->start_group_wait_time);
-       blkio_clear_blkg_waiting(stats);
+       cfqg_stats_clear_waiting(stats);
 }
 
 /* This should be called with the queue_lock held. */
-static void blkio_set_start_group_wait_time(struct blkio_group *blkg,
-                                           struct blkio_policy_type *pol,
-                                           struct blkio_group *curr_blkg)
+static void cfqg_stats_set_start_group_wait_time(struct cfq_group *cfqg,
+                                                struct cfq_group *curr_cfqg)
 {
-       struct blkg_policy_data *pd = blkg->pd[pol->plid];
+       struct cfqg_stats *stats = &cfqg->stats;
 
-       if (blkio_blkg_waiting(&pd->stats))
+       if (cfqg_stats_waiting(stats))
                return;
-       if (blkg == curr_blkg)
+       if (cfqg == curr_cfqg)
                return;
-       pd->stats.start_group_wait_time = sched_clock();
-       blkio_mark_blkg_waiting(&pd->stats);
+       stats->start_group_wait_time = sched_clock();
+       cfqg_stats_mark_waiting(stats);
 }
 
 /* This should be called with the queue_lock held. */
-static void blkio_end_empty_time(struct blkio_group_stats *stats)
+static void cfqg_stats_end_empty_time(struct cfqg_stats *stats)
 {
        unsigned long long now;
 
-       if (!blkio_blkg_empty(stats))
+       if (!cfqg_stats_empty(stats))
                return;
 
        now = sched_clock();
        if (time_after64(now, stats->start_empty_time))
                blkg_stat_add(&stats->empty_time,
                              now - stats->start_empty_time);
-       blkio_clear_blkg_empty(stats);
+       cfqg_stats_clear_empty(stats);
 }
 
-static void cfq_blkiocg_update_dequeue_stats(struct blkio_group *blkg,
-                                            struct blkio_policy_type *pol,
-                                            unsigned long dequeue)
+static void cfqg_stats_update_dequeue(struct cfq_group *cfqg)
 {
-       struct blkg_policy_data *pd = blkg->pd[pol->plid];
-
-       lockdep_assert_held(blkg->q->queue_lock);
-
-       blkg_stat_add(&pd->stats.dequeue, dequeue);
+       blkg_stat_add(&cfqg->stats.dequeue, 1);
 }
 
-static void cfq_blkiocg_set_start_empty_time(struct blkio_group *blkg,
-                                            struct blkio_policy_type *pol)
+static void cfqg_stats_set_start_empty_time(struct cfq_group *cfqg)
 {
-       struct blkio_group_stats *stats = &blkg->pd[pol->plid]->stats;
-
-       lockdep_assert_held(blkg->q->queue_lock);
+       struct cfqg_stats *stats = &cfqg->stats;
 
        if (blkg_rwstat_sum(&stats->queued))
                return;
@@ -467,72 +498,57 @@ static void cfq_blkiocg_set_start_empty_time(struct blkio_group *blkg,
         * request in parent group and moved to this group while being added
         * to service tree. Just ignore the event and move on.
         */
-       if (blkio_blkg_empty(stats))
+       if (cfqg_stats_empty(stats))
                return;
 
        stats->start_empty_time = sched_clock();
-       blkio_mark_blkg_empty(stats);
+       cfqg_stats_mark_empty(stats);
 }
 
-static void cfq_blkiocg_update_idle_time_stats(struct blkio_group *blkg,
-                                              struct blkio_policy_type *pol)
+static void cfqg_stats_update_idle_time(struct cfq_group *cfqg)
 {
-       struct blkio_group_stats *stats = &blkg->pd[pol->plid]->stats;
+       struct cfqg_stats *stats = &cfqg->stats;
 
-       lockdep_assert_held(blkg->q->queue_lock);
-
-       if (blkio_blkg_idling(stats)) {
+       if (cfqg_stats_idling(stats)) {
                unsigned long long now = sched_clock();
 
                if (time_after64(now, stats->start_idle_time))
                        blkg_stat_add(&stats->idle_time,
                                      now - stats->start_idle_time);
-               blkio_clear_blkg_idling(stats);
+               cfqg_stats_clear_idling(stats);
        }
 }
 
-static void cfq_blkiocg_update_set_idle_time_stats(struct blkio_group *blkg,
-                                                  struct blkio_policy_type *pol)
+static void cfqg_stats_set_start_idle_time(struct cfq_group *cfqg)
 {
-       struct blkio_group_stats *stats = &blkg->pd[pol->plid]->stats;
+       struct cfqg_stats *stats = &cfqg->stats;
 
-       lockdep_assert_held(blkg->q->queue_lock);
-       BUG_ON(blkio_blkg_idling(stats));
+       BUG_ON(cfqg_stats_idling(stats));
 
        stats->start_idle_time = sched_clock();
-       blkio_mark_blkg_idling(stats);
+       cfqg_stats_mark_idling(stats);
 }
 
-static void cfq_blkiocg_update_avg_queue_size_stats(struct blkio_group *blkg,
-                                                   struct blkio_policy_type *pol)
+static void cfqg_stats_update_avg_queue_size(struct cfq_group *cfqg)
 {
-       struct blkio_group_stats *stats = &blkg->pd[pol->plid]->stats;
-
-       lockdep_assert_held(blkg->q->queue_lock);
+       struct cfqg_stats *stats = &cfqg->stats;
 
        blkg_stat_add(&stats->avg_queue_size_sum,
                      blkg_rwstat_sum(&stats->queued));
        blkg_stat_add(&stats->avg_queue_size_samples, 1);
-       blkio_update_group_wait_time(stats);
+       cfqg_stats_update_group_wait_time(stats);
 }
 
 #else  /* CONFIG_CFQ_GROUP_IOSCHED && CONFIG_DEBUG_BLK_CGROUP */
 
-static void blkio_set_start_group_wait_time(struct blkio_group *blkg,
-                                           struct blkio_policy_type *pol,
-                                           struct blkio_group *curr_blkg) { }
-static void blkio_end_empty_time(struct blkio_group_stats *stats) { }
-static void cfq_blkiocg_update_dequeue_stats(struct blkio_group *blkg,
-                                            struct blkio_policy_type *pol,
-                                            unsigned long dequeue) { }
-static void cfq_blkiocg_set_start_empty_time(struct blkio_group *blkg,
-                                            struct blkio_policy_type *pol) { }
-static void cfq_blkiocg_update_idle_time_stats(struct blkio_group *blkg,
-                                              struct blkio_policy_type *pol) { }
-static void cfq_blkiocg_update_set_idle_time_stats(struct blkio_group *blkg,
-                                                  struct blkio_policy_type *pol) { }
-static void cfq_blkiocg_update_avg_queue_size_stats(struct blkio_group *blkg,
-                                                   struct blkio_policy_type *pol) { }
+static void cfqg_stats_set_start_group_wait_time(struct cfq_group *cfqg,
+                                                struct cfq_group *curr_cfqg) { }
+static void cfqg_stats_end_empty_time(struct cfqg_stats *stats) { }
+static void cfqg_stats_update_dequeue(struct cfq_group *cfqg) { }
+static void cfqg_stats_set_start_empty_time(struct cfq_group *cfqg) { }
+static void cfqg_stats_update_idle_time(struct cfq_group *cfqg) { }
+static void cfqg_stats_set_start_idle_time(struct cfq_group *cfqg) { }
+static void cfqg_stats_update_avg_queue_size(struct cfq_group *cfqg) { }
 
 #endif /* CONFIG_CFQ_GROUP_IOSCHED && CONFIG_DEBUG_BLK_CGROUP */
 
@@ -567,80 +583,46 @@ static inline void cfqg_put(struct cfq_group *cfqg)
        blk_add_trace_msg((cfqd)->queue, "%s " fmt,                     \
                        blkg_path(cfqg_to_blkg((cfqg))), ##args)        \
 
-static inline void cfq_blkiocg_update_io_add_stats(struct blkio_group *blkg,
-                       struct blkio_policy_type *pol,
-                       struct blkio_group *curr_blkg,
-                       bool direction, bool sync)
+static inline void cfqg_stats_update_io_add(struct cfq_group *cfqg,
+                                           struct cfq_group *curr_cfqg, int rw)
 {
-       struct blkio_group_stats *stats = &blkg->pd[pol->plid]->stats;
-       int rw = (direction ? REQ_WRITE : 0) | (sync ? REQ_SYNC : 0);
-
-       lockdep_assert_held(blkg->q->queue_lock);
-
-       blkg_rwstat_add(&stats->queued, rw, 1);
-       blkio_end_empty_time(stats);
-       blkio_set_start_group_wait_time(blkg, pol, curr_blkg);
+       blkg_rwstat_add(&cfqg->stats.queued, rw, 1);
+       cfqg_stats_end_empty_time(&cfqg->stats);
+       cfqg_stats_set_start_group_wait_time(cfqg, curr_cfqg);
 }
 
-static inline void cfq_blkiocg_update_timeslice_used(struct blkio_group *blkg,
-                       struct blkio_policy_type *pol, unsigned long time,
-                       unsigned long unaccounted_time)
+static inline void cfqg_stats_update_timeslice_used(struct cfq_group *cfqg,
+                       unsigned long time, unsigned long unaccounted_time)
 {
-       struct blkio_group_stats *stats = &blkg->pd[pol->plid]->stats;
-
-       lockdep_assert_held(blkg->q->queue_lock);
-
-       blkg_stat_add(&stats->time, time);
+       blkg_stat_add(&cfqg->stats.time, time);
 #ifdef CONFIG_DEBUG_BLK_CGROUP
-       blkg_stat_add(&stats->unaccounted_time, unaccounted_time);
+       blkg_stat_add(&cfqg->stats.unaccounted_time, unaccounted_time);
 #endif
 }
 
-static inline void cfq_blkiocg_update_io_remove_stats(struct blkio_group *blkg,
-                       struct blkio_policy_type *pol, bool direction,
-                       bool sync)
+static inline void cfqg_stats_update_io_remove(struct cfq_group *cfqg, int rw)
 {
-       struct blkio_group_stats *stats = &blkg->pd[pol->plid]->stats;
-       int rw = (direction ? REQ_WRITE : 0) | (sync ? REQ_SYNC : 0);
-
-       lockdep_assert_held(blkg->q->queue_lock);
-
-       blkg_rwstat_add(&stats->queued, rw, -1);
+       blkg_rwstat_add(&cfqg->stats.queued, rw, -1);
 }
 
-static inline void cfq_blkiocg_update_io_merged_stats(struct blkio_group *blkg,
-                       struct blkio_policy_type *pol, bool direction,
-                       bool sync)
+static inline void cfqg_stats_update_io_merged(struct cfq_group *cfqg, int rw)
 {
-       struct blkio_group_stats *stats = &blkg->pd[pol->plid]->stats;
-       int rw = (direction ? REQ_WRITE : 0) | (sync ? REQ_SYNC : 0);
-
-       lockdep_assert_held(blkg->q->queue_lock);
-
-       blkg_rwstat_add(&stats->merged, rw, 1);
+       blkg_rwstat_add(&cfqg->stats.merged, rw, 1);
 }
 
-static inline void cfq_blkiocg_update_dispatch_stats(struct blkio_group *blkg,
-                       struct blkio_policy_type *pol, uint64_t bytes,
-                       bool direction, bool sync)
+static inline void cfqg_stats_update_dispatch(struct cfq_group *cfqg,
+                                             uint64_t bytes, int rw)
 {
-       struct blkio_group_stats *stats = &blkg->pd[pol->plid]->stats;
-       int rw = (direction ? REQ_WRITE : 0) | (sync ? REQ_SYNC : 0);
-
-       blkg_stat_add(&stats->sectors, bytes >> 9);
-       blkg_rwstat_add(&stats->serviced, rw, 1);
-       blkg_rwstat_add(&stats->service_bytes, rw, bytes);
+       blkg_stat_add(&cfqg->stats.sectors, bytes >> 9);
+       blkg_rwstat_add(&cfqg->stats.serviced, rw, 1);
+       blkg_rwstat_add(&cfqg->stats.service_bytes, rw, bytes);
 }
 
-static inline void cfq_blkiocg_update_completion_stats(struct blkio_group *blkg,
-                       struct blkio_policy_type *pol, uint64_t start_time,
-                       uint64_t io_start_time, bool direction, bool sync)
+static inline void cfqg_stats_update_completion(struct cfq_group *cfqg,
+                       uint64_t start_time, uint64_t io_start_time, int rw)
 {
-       struct blkio_group_stats *stats = &blkg->pd[pol->plid]->stats;
+       struct cfqg_stats *stats = &cfqg->stats;
        unsigned long long now = sched_clock();
-       int rw = (direction ? REQ_WRITE : 0) | (sync ? REQ_SYNC : 0);
-
-       lockdep_assert_held(blkg->q->queue_lock);
 
        if (time_after64(now, io_start_time))
                blkg_rwstat_add(&stats->service_time, rw, now - io_start_time);
@@ -649,6 +631,29 @@ static inline void cfq_blkiocg_update_completion_stats(struct blkio_group *blkg,
                                io_start_time - start_time);
 }
 
+static void cfqg_stats_reset(struct blkio_group *blkg)
+{
+       struct cfq_group *cfqg = blkg_to_cfqg(blkg);
+       struct cfqg_stats *stats = &cfqg->stats;
+
+       /* queued stats shouldn't be cleared */
+       blkg_rwstat_reset(&stats->service_bytes);
+       blkg_rwstat_reset(&stats->serviced);
+       blkg_rwstat_reset(&stats->merged);
+       blkg_rwstat_reset(&stats->service_time);
+       blkg_rwstat_reset(&stats->wait_time);
+       blkg_stat_reset(&stats->time);
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+       blkg_stat_reset(&stats->unaccounted_time);
+       blkg_stat_reset(&stats->avg_queue_size_sum);
+       blkg_stat_reset(&stats->avg_queue_size_samples);
+       blkg_stat_reset(&stats->dequeue);
+       blkg_stat_reset(&stats->group_wait_time);
+       blkg_stat_reset(&stats->idle_time);
+       blkg_stat_reset(&stats->empty_time);
+#endif
+}
+
 #else  /* CONFIG_CFQ_GROUP_IOSCHED */
 
 static inline struct cfq_group *blkg_to_cfqg(struct blkio_group *blkg) { return NULL; }
@@ -660,25 +665,16 @@ static inline void cfqg_put(struct cfq_group *cfqg) { }
        blk_add_trace_msg((cfqd)->queue, "cfq%d " fmt, (cfqq)->pid, ##args)
 #define cfq_log_cfqg(cfqd, cfqg, fmt, args...)         do {} while (0)
 
-static inline void cfq_blkiocg_update_io_add_stats(struct blkio_group *blkg,
-                       struct blkio_policy_type *pol,
-                       struct blkio_group *curr_blkg, bool direction,
-                       bool sync) { }
-static inline void cfq_blkiocg_update_timeslice_used(struct blkio_group *blkg,
-                       struct blkio_policy_type *pol, unsigned long time,
-                       unsigned long unaccounted_time) { }
-static inline void cfq_blkiocg_update_io_remove_stats(struct blkio_group *blkg,
-                       struct blkio_policy_type *pol, bool direction,
-                       bool sync) { }
-static inline void cfq_blkiocg_update_io_merged_stats(struct blkio_group *blkg,
-                       struct blkio_policy_type *pol, bool direction,
-                       bool sync) { }
-static inline void cfq_blkiocg_update_dispatch_stats(struct blkio_group *blkg,
-                       struct blkio_policy_type *pol, uint64_t bytes,
-                       bool direction, bool sync) { }
-static inline void cfq_blkiocg_update_completion_stats(struct blkio_group *blkg,
-                       struct blkio_policy_type *pol, uint64_t start_time,
-                       uint64_t io_start_time, bool direction, bool sync) { }
+static inline void cfqg_stats_update_io_add(struct cfq_group *cfqg,
+                       struct cfq_group *curr_cfqg, int rw) { }
+static inline void cfqg_stats_update_timeslice_used(struct cfq_group *cfqg,
+                       unsigned long time, unsigned long unaccounted_time) { }
+static inline void cfqg_stats_update_io_remove(struct cfq_group *cfqg, int rw) { }
+static inline void cfqg_stats_update_io_merged(struct cfq_group *cfqg, int rw) { }
+static inline void cfqg_stats_update_dispatch(struct cfq_group *cfqg,
+                                             uint64_t bytes, int rw) { }
+static inline void cfqg_stats_update_completion(struct cfq_group *cfqg,
+                       uint64_t start_time, uint64_t io_start_time, int rw) { }
 
 #endif /* CONFIG_CFQ_GROUP_IOSCHED */
 
@@ -1233,8 +1229,7 @@ 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;
-       cfq_blkiocg_update_dequeue_stats(cfqg_to_blkg(cfqg),
-                                        &blkio_policy_cfq, 1);
+       cfqg_stats_update_dequeue(cfqg);
 }
 
 static inline unsigned int cfq_cfqq_slice_usage(struct cfq_queue *cfqq,
@@ -1306,9 +1301,8 @@ static void cfq_group_served(struct cfq_data *cfqd, struct cfq_group *cfqg,
                     "sl_used=%u disp=%u charge=%u iops=%u sect=%lu",
                     used_sl, cfqq->slice_dispatch, charge,
                     iops_mode(cfqd), cfqq->nr_sectors);
-       cfq_blkiocg_update_timeslice_used(cfqg_to_blkg(cfqg), &blkio_policy_cfq,
-                                         used_sl, unaccounted_sl);
-       cfq_blkiocg_set_start_empty_time(cfqg_to_blkg(cfqg), &blkio_policy_cfq);
+       cfqg_stats_update_timeslice_used(cfqg, used_sl, unaccounted_sl);
+       cfqg_stats_set_start_empty_time(cfqg);
 }
 
 /**
@@ -1456,14 +1450,15 @@ static int blkcg_set_weight(struct cgroup *cgrp, struct cftype *cft, u64 val)
 }
 
 #ifdef CONFIG_DEBUG_BLK_CGROUP
-static u64 blkg_prfill_avg_queue_size(struct seq_file *sf,
+static u64 cfqg_prfill_avg_queue_size(struct seq_file *sf,
                                      struct blkg_policy_data *pd, int off)
 {
-       u64 samples = blkg_stat_read(&pd->stats.avg_queue_size_samples);
+       struct cfq_group *cfqg = (void *)pd->pdata;
+       u64 samples = blkg_stat_read(&cfqg->stats.avg_queue_size_samples);
        u64 v = 0;
 
        if (samples) {
-               v = blkg_stat_read(&pd->stats.avg_queue_size_sum);
+               v = blkg_stat_read(&cfqg->stats.avg_queue_size_sum);
                do_div(v, samples);
        }
        __blkg_prfill_u64(sf, pd, v);
@@ -1471,12 +1466,12 @@ static u64 blkg_prfill_avg_queue_size(struct seq_file *sf,
 }
 
 /* print avg_queue_size */
-static int blkcg_print_avg_queue_size(struct cgroup *cgrp, struct cftype *cft,
-                                     struct seq_file *sf)
+static int cfqg_print_avg_queue_size(struct cgroup *cgrp, struct cftype *cft,
+                                    struct seq_file *sf)
 {
        struct blkio_cgroup *blkcg = cgroup_to_blkio_cgroup(cgrp);
 
-       blkcg_print_blkgs(sf, blkcg, blkg_prfill_avg_queue_size,
+       blkcg_print_blkgs(sf, blkcg, cfqg_prfill_avg_queue_size,
                          BLKIO_POLICY_PROP, 0, false);
        return 0;
 }
@@ -1497,84 +1492,84 @@ static struct cftype cfq_blkcg_files[] = {
        {
                .name = "time",
                .private = BLKCG_STAT_PRIV(BLKIO_POLICY_PROP,
-                               offsetof(struct blkio_group_stats, time)),
+                               offsetof(struct cfq_group, stats.time)),
                .read_seq_string = blkcg_print_stat,
        },
        {
                .name = "sectors",
                .private = BLKCG_STAT_PRIV(BLKIO_POLICY_PROP,
-                               offsetof(struct blkio_group_stats, sectors)),
+                               offsetof(struct cfq_group, stats.sectors)),
                .read_seq_string = blkcg_print_stat,
        },
        {
                .name = "io_service_bytes",
                .private = BLKCG_STAT_PRIV(BLKIO_POLICY_PROP,
-                               offsetof(struct blkio_group_stats, service_bytes)),
+                               offsetof(struct cfq_group, stats.service_bytes)),
                .read_seq_string = blkcg_print_rwstat,
        },
        {
                .name = "io_serviced",
                .private = BLKCG_STAT_PRIV(BLKIO_POLICY_PROP,
-                               offsetof(struct blkio_group_stats, serviced)),
+                               offsetof(struct cfq_group, stats.serviced)),
                .read_seq_string = blkcg_print_rwstat,
        },
        {
                .name = "io_service_time",
                .private = BLKCG_STAT_PRIV(BLKIO_POLICY_PROP,
-                               offsetof(struct blkio_group_stats, service_time)),
+                               offsetof(struct cfq_group, stats.service_time)),
                .read_seq_string = blkcg_print_rwstat,
        },
        {
                .name = "io_wait_time",
                .private = BLKCG_STAT_PRIV(BLKIO_POLICY_PROP,
-                               offsetof(struct blkio_group_stats, wait_time)),
+                               offsetof(struct cfq_group, stats.wait_time)),
                .read_seq_string = blkcg_print_rwstat,
        },
        {
                .name = "io_merged",
                .private = BLKCG_STAT_PRIV(BLKIO_POLICY_PROP,
-                               offsetof(struct blkio_group_stats, merged)),
+                               offsetof(struct cfq_group, stats.merged)),
                .read_seq_string = blkcg_print_rwstat,
        },
        {
                .name = "io_queued",
                .private = BLKCG_STAT_PRIV(BLKIO_POLICY_PROP,
-                               offsetof(struct blkio_group_stats, queued)),
+                               offsetof(struct cfq_group, stats.queued)),
                .read_seq_string = blkcg_print_rwstat,
        },
 #ifdef CONFIG_DEBUG_BLK_CGROUP
        {
                .name = "avg_queue_size",
-               .read_seq_string = blkcg_print_avg_queue_size,
+               .read_seq_string = cfqg_print_avg_queue_size,
        },
        {
                .name = "group_wait_time",
                .private = BLKCG_STAT_PRIV(BLKIO_POLICY_PROP,
-                               offsetof(struct blkio_group_stats, group_wait_time)),
+                               offsetof(struct cfq_group, stats.group_wait_time)),
                .read_seq_string = blkcg_print_stat,
        },
        {
                .name = "idle_time",
                .private = BLKCG_STAT_PRIV(BLKIO_POLICY_PROP,
-                               offsetof(struct blkio_group_stats, idle_time)),
+                               offsetof(struct cfq_group, stats.idle_time)),
                .read_seq_string = blkcg_print_stat,
        },
        {
                .name = "empty_time",
                .private = BLKCG_STAT_PRIV(BLKIO_POLICY_PROP,
-                               offsetof(struct blkio_group_stats, empty_time)),
+                               offsetof(struct cfq_group, stats.empty_time)),
                .read_seq_string = blkcg_print_stat,
        },
        {
                .name = "dequeue",
                .private = BLKCG_STAT_PRIV(BLKIO_POLICY_PROP,
-                               offsetof(struct blkio_group_stats, dequeue)),
+                               offsetof(struct cfq_group, stats.dequeue)),
                .read_seq_string = blkcg_print_stat,
        },
        {
                .name = "unaccounted_time",
                .private = BLKCG_STAT_PRIV(BLKIO_POLICY_PROP,
-                               offsetof(struct blkio_group_stats, unaccounted_time)),
+                               offsetof(struct cfq_group, stats.unaccounted_time)),
                .read_seq_string = blkcg_print_stat,
        },
 #endif /* CONFIG_DEBUG_BLK_CGROUP */
@@ -1858,14 +1853,10 @@ static void cfq_reposition_rq_rb(struct cfq_queue *cfqq, struct request *rq)
 {
        elv_rb_del(&cfqq->sort_list, rq);
        cfqq->queued[rq_is_sync(rq)]--;
-       cfq_blkiocg_update_io_remove_stats(cfqg_to_blkg(RQ_CFQG(rq)),
-                                          &blkio_policy_cfq, rq_data_dir(rq),
-                                          rq_is_sync(rq));
+       cfqg_stats_update_io_remove(RQ_CFQG(rq), rq->cmd_flags);
        cfq_add_rq_rb(rq);
-       cfq_blkiocg_update_io_add_stats(cfqg_to_blkg(RQ_CFQG(rq)),
-                                       &blkio_policy_cfq,
-                                       cfqg_to_blkg(cfqq->cfqd->serving_group),
-                                       rq_data_dir(rq), rq_is_sync(rq));
+       cfqg_stats_update_io_add(RQ_CFQG(rq), cfqq->cfqd->serving_group,
+                                rq->cmd_flags);
 }
 
 static struct request *
@@ -1921,9 +1912,7 @@ static void cfq_remove_request(struct request *rq)
        cfq_del_rq_rb(rq);
 
        cfqq->cfqd->rq_queued--;
-       cfq_blkiocg_update_io_remove_stats(cfqg_to_blkg(RQ_CFQG(rq)),
-                                          &blkio_policy_cfq, rq_data_dir(rq),
-                                          rq_is_sync(rq));
+       cfqg_stats_update_io_remove(RQ_CFQG(rq), rq->cmd_flags);
        if (rq->cmd_flags & REQ_PRIO) {
                WARN_ON(!cfqq->prio_pending);
                cfqq->prio_pending--;
@@ -1958,9 +1947,7 @@ static void cfq_merged_request(struct request_queue *q, struct request *req,
 static void cfq_bio_merged(struct request_queue *q, struct request *req,
                                struct bio *bio)
 {
-       cfq_blkiocg_update_io_merged_stats(cfqg_to_blkg(RQ_CFQG(req)),
-                                          &blkio_policy_cfq, bio_data_dir(bio),
-                                          cfq_bio_sync(bio));
+       cfqg_stats_update_io_merged(RQ_CFQG(req), bio->bi_rw);
 }
 
 static void
@@ -1982,9 +1969,7 @@ cfq_merged_requests(struct request_queue *q, struct request *rq,
        if (cfqq->next_rq == next)
                cfqq->next_rq = rq;
        cfq_remove_request(next);
-       cfq_blkiocg_update_io_merged_stats(cfqg_to_blkg(RQ_CFQG(rq)),
-                                          &blkio_policy_cfq, rq_data_dir(next),
-                                          rq_is_sync(next));
+       cfqg_stats_update_io_merged(RQ_CFQG(rq), next->cmd_flags);
 
        cfqq = RQ_CFQQ(next);
        /*
@@ -2025,8 +2010,7 @@ static int cfq_allow_merge(struct request_queue *q, struct request *rq,
 static inline void cfq_del_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq)
 {
        del_timer(&cfqd->idle_slice_timer);
-       cfq_blkiocg_update_idle_time_stats(cfqg_to_blkg(cfqq->cfqg),
-                                          &blkio_policy_cfq);
+       cfqg_stats_update_idle_time(cfqq->cfqg);
 }
 
 static void __cfq_set_active_queue(struct cfq_data *cfqd,
@@ -2035,8 +2019,7 @@ static void __cfq_set_active_queue(struct cfq_data *cfqd,
        if (cfqq) {
                cfq_log_cfqq(cfqd, cfqq, "set_active wl_prio:%d wl_type:%d",
                                cfqd->serving_prio, cfqd->serving_type);
-               cfq_blkiocg_update_avg_queue_size_stats(cfqg_to_blkg(cfqq->cfqg),
-                                                       &blkio_policy_cfq);
+               cfqg_stats_update_avg_queue_size(cfqq->cfqg);
                cfqq->slice_start = 0;
                cfqq->dispatch_start = jiffies;
                cfqq->allocated_slice = 0;
@@ -2384,8 +2367,7 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd)
                sl = cfqd->cfq_slice_idle;
 
        mod_timer(&cfqd->idle_slice_timer, jiffies + sl);
-       cfq_blkiocg_update_set_idle_time_stats(cfqg_to_blkg(cfqq->cfqg),
-                                              &blkio_policy_cfq);
+       cfqg_stats_set_start_idle_time(cfqq->cfqg);
        cfq_log_cfqq(cfqd, cfqq, "arm_idle: %lu group_idle: %d", sl,
                        group_idle ? 1 : 0);
 }
@@ -2408,9 +2390,7 @@ static void cfq_dispatch_insert(struct request_queue *q, struct request *rq)
 
        cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]++;
        cfqq->nr_sectors += blk_rq_sectors(rq);
-       cfq_blkiocg_update_dispatch_stats(cfqg_to_blkg(cfqq->cfqg),
-                                         &blkio_policy_cfq, blk_rq_bytes(rq),
-                                         rq_data_dir(rq), rq_is_sync(rq));
+       cfqg_stats_update_dispatch(cfqq->cfqg, blk_rq_bytes(rq), rq->cmd_flags);
 }
 
 /*
@@ -3513,9 +3493,7 @@ cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq,
                                cfq_clear_cfqq_wait_request(cfqq);
                                __blk_run_queue(cfqd->queue);
                        } else {
-                               cfq_blkiocg_update_idle_time_stats(
-                                               cfqg_to_blkg(cfqq->cfqg),
-                                               &blkio_policy_cfq);
+                               cfqg_stats_update_idle_time(cfqq->cfqg);
                                cfq_mark_cfqq_must_dispatch(cfqq);
                        }
                }
@@ -3542,10 +3520,8 @@ static void cfq_insert_request(struct request_queue *q, struct request *rq)
        rq_set_fifo_time(rq, jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]);
        list_add_tail(&rq->queuelist, &cfqq->fifo);
        cfq_add_rq_rb(rq);
-       cfq_blkiocg_update_io_add_stats(cfqg_to_blkg(RQ_CFQG(rq)),
-                                       &blkio_policy_cfq,
-                                       cfqg_to_blkg(cfqd->serving_group),
-                                       rq_data_dir(rq), rq_is_sync(rq));
+       cfqg_stats_update_io_add(RQ_CFQG(rq), cfqd->serving_group,
+                                rq->cmd_flags);
        cfq_rq_enqueued(cfqd, cfqq, rq);
 }
 
@@ -3641,10 +3617,8 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq)
        cfqd->rq_in_driver--;
        cfqq->dispatched--;
        (RQ_CFQG(rq))->dispatched--;
-       cfq_blkiocg_update_completion_stats(cfqg_to_blkg(cfqq->cfqg),
-                       &blkio_policy_cfq, rq_start_time_ns(rq),
-                       rq_io_start_time_ns(rq), rq_data_dir(rq),
-                       rq_is_sync(rq));
+       cfqg_stats_update_completion(cfqq->cfqg, rq_start_time_ns(rq),
+                                    rq_io_start_time_ns(rq), rq->cmd_flags);
 
        cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]--;
 
@@ -4184,6 +4158,7 @@ static struct elevator_type iosched_cfq = {
 static struct blkio_policy_type blkio_policy_cfq = {
        .ops = {
                .blkio_init_group_fn =          cfq_init_blkio_group,
+               .blkio_reset_group_stats_fn =   cfqg_stats_reset,
        },
        .plid = BLKIO_POLICY_PROP,
        .pdata_size = sizeof(struct cfq_group),