3 files changed, 194 insertions, 25 deletions

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 5be39813fc9b..ad6843f2e0ab 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -55,12 +55,15 @@ struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup)
 }
 EXPORT_SYMBOL_GPL(cgroup_to_blkio_cgroup);
 
-void blkiocg_update_blkio_group_stats(struct blkio_group *blkg,
-                                                unsigned long time)
+void blkiocg_update_timeslice_used(struct blkio_group *blkg, unsigned long time)
 {
-        blkg->time += time;
+        unsigned long flags;
+
+        spin_lock_irqsave(&blkg->stats_lock, flags);
+        blkg->stats.time += time;
+        spin_unlock_irqrestore(&blkg->stats_lock, flags);
 }
-EXPORT_SYMBOL_GPL(blkiocg_update_blkio_group_stats);
+EXPORT_SYMBOL_GPL(blkiocg_update_timeslice_used);
 
 void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
                         struct blkio_group *blkg, void *key, dev_t dev)
@@ -170,13 +173,121 @@ blkiocg_weight_write(struct cgroup *cgroup, struct cftype *cftype, u64 val)
         return 0;
 }
 
-#define SHOW_FUNCTION_PER_GROUP(__VAR)                                  \
+static int
+blkiocg_reset_write(struct cgroup *cgroup, struct cftype *cftype, u64 val)
+{
+        struct blkio_cgroup *blkcg;
+        struct blkio_group *blkg;
+        struct hlist_node *n;
+        struct blkio_group_stats *stats;
+
+        blkcg = cgroup_to_blkio_cgroup(cgroup);
+        spin_lock_irq(&blkcg->lock);
+        hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) {
+                spin_lock(&blkg->stats_lock);
+                stats = &blkg->stats;
+                memset(stats, 0, sizeof(struct blkio_group_stats));
+                spin_unlock(&blkg->stats_lock);
+        }
+        spin_unlock_irq(&blkcg->lock);
+        return 0;
+}
+
+void get_key_name(int type, char *disk_id, char *str, int chars_left)
+{
+        strlcpy(str, disk_id, chars_left);
+        chars_left -= strlen(str);
+        if (chars_left <= 0) {
+                printk(KERN_WARNING
+                        "Possibly incorrect cgroup stat display format");
+                return;
+        }
+        switch (type) {
+        case IO_READ:
+                strlcat(str, " Read", chars_left);
+                break;
+        case IO_WRITE:
+                strlcat(str, " Write", chars_left);
+                break;
+        case IO_SYNC:
+                strlcat(str, " Sync", chars_left);
+                break;
+        case IO_ASYNC:
+                strlcat(str, " Async", chars_left);
+                break;
+        case IO_TYPE_MAX:
+                strlcat(str, " Total", chars_left);
+                break;
+        default:
+                strlcat(str, " Invalid", chars_left);
+        }
+}
+
+typedef uint64_t (get_var) (struct blkio_group *, int);
+
+#define MAX_KEY_LEN 100
+uint64_t get_typed_stat(struct blkio_group *blkg, struct cgroup_map_cb *cb,
+                get_var *getvar, char *disk_id)
+{
+        uint64_t disk_total;
+        char key_str[MAX_KEY_LEN];
+        int type;
+
+        for (type = 0; type < IO_TYPE_MAX; type++) {
+                get_key_name(type, disk_id, key_str, MAX_KEY_LEN);
+                cb->fill(cb, key_str, getvar(blkg, type));
+        }
+        disk_total = getvar(blkg, IO_READ) + getvar(blkg, IO_WRITE);
+        get_key_name(IO_TYPE_MAX, disk_id, key_str, MAX_KEY_LEN);
+        cb->fill(cb, key_str, disk_total);
+        return disk_total;
+}
+
+uint64_t get_stat(struct blkio_group *blkg, struct cgroup_map_cb *cb,
+                get_var *getvar, char *disk_id)
+{
+        uint64_t var = getvar(blkg, 0);
+        cb->fill(cb, disk_id, var);
+        return var;
+}
+
+#define GET_STAT_INDEXED(__VAR)                                         \
+uint64_t get_##__VAR##_stat(struct blkio_group *blkg, int type)         \
+{                                                                       \
+        return blkg->stats.__VAR[type];                                 \
+}                                                                       \
+
+GET_STAT_INDEXED(io_service_bytes);
+GET_STAT_INDEXED(io_serviced);
+GET_STAT_INDEXED(io_service_time);
+GET_STAT_INDEXED(io_wait_time);
+#undef GET_STAT_INDEXED
+
+#define GET_STAT(__VAR, __CONV)                                         \
+uint64_t get_##__VAR##_stat(struct blkio_group *blkg, int dummy)        \
+{                                                                       \
+        uint64_t data = blkg->stats.__VAR;                              \
+        if (__CONV)                                                     \
+                data = (uint64_t)jiffies_to_msecs(data) * NSEC_PER_MSEC;\
+        return data;                                                    \
+}
+
+GET_STAT(time, 1);
+GET_STAT(sectors, 0);
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+GET_STAT(dequeue, 0);
+#endif
+#undef GET_STAT
+
+#define SHOW_FUNCTION_PER_GROUP(__VAR, get_stats, getvar, show_total)   \
 static int blkiocg_##__VAR##_read(struct cgroup *cgroup,                \
-                        struct cftype *cftype, struct seq_file *m)      \
+                struct cftype *cftype, struct cgroup_map_cb *cb)        \
 {                                                                       \
         struct blkio_cgroup *blkcg;                                     \
         struct blkio_group *blkg;                                       \
         struct hlist_node *n;                                           \
+        uint64_t cgroup_total = 0;                                      \
+        char disk_id[10];                                               \
                                                                         \
         if (!cgroup_lock_live_group(cgroup))                            \
                 return -ENODEV;                                         \
@@ -184,19 +295,32 @@ static int blkiocg_##__VAR##_read(struct cgroup *cgroup,		\
         blkcg = cgroup_to_blkio_cgroup(cgroup);                         \
         rcu_read_lock();                                                \
         hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) {\
-                if (blkg->dev)                                          \
-                        seq_printf(m, "%u:%u %lu\n", MAJOR(blkg->dev),  \
-                                 MINOR(blkg->dev), blkg->__VAR);        \
+                if (blkg->dev) {                                        \
+                        spin_lock_irq(&blkg->stats_lock);               \
+                        snprintf(disk_id, 10, "%u:%u", MAJOR(blkg->dev),\
+                                        MINOR(blkg->dev));              \
+                        cgroup_total += get_stats(blkg, cb, getvar,     \
+                                                disk_id);               \
+                        spin_unlock_irq(&blkg->stats_lock);             \
+                }                                                       \
         }                                                               \
+        if (show_total)                                                 \
+                cb->fill(cb, "Total", cgroup_total);                    \
         rcu_read_unlock();                                              \
         cgroup_unlock();                                                \
         return 0;                                                       \
 }
 
-SHOW_FUNCTION_PER_GROUP(time);
-SHOW_FUNCTION_PER_GROUP(sectors);
+SHOW_FUNCTION_PER_GROUP(time, get_stat, get_time_stat, 0);
+SHOW_FUNCTION_PER_GROUP(sectors, get_stat, get_sectors_stat, 0);
+SHOW_FUNCTION_PER_GROUP(io_service_bytes, get_typed_stat,
+                        get_io_service_bytes_stat, 1);
+SHOW_FUNCTION_PER_GROUP(io_serviced, get_typed_stat, get_io_serviced_stat, 1);
+SHOW_FUNCTION_PER_GROUP(io_service_time, get_typed_stat,
+                        get_io_service_time_stat, 1);
+SHOW_FUNCTION_PER_GROUP(io_wait_time, get_typed_stat, get_io_wait_time_stat, 1);
 #ifdef CONFIG_DEBUG_BLK_CGROUP
-SHOW_FUNCTION_PER_GROUP(dequeue);
+SHOW_FUNCTION_PER_GROUP(dequeue, get_stat, get_dequeue_stat, 0);
 #endif
 #undef SHOW_FUNCTION_PER_GROUP
 
@@ -204,7 +328,7 @@ SHOW_FUNCTION_PER_GROUP(dequeue);
 void blkiocg_update_blkio_group_dequeue_stats(struct blkio_group *blkg,
                         unsigned long dequeue)
 {
-        blkg->dequeue += dequeue;
+        blkg->stats.dequeue += dequeue;
 }
 EXPORT_SYMBOL_GPL(blkiocg_update_blkio_group_dequeue_stats);
 #endif
@@ -217,16 +341,38 @@ struct cftype blkio_files[] = {
         },
         {
                 .name = "time",
-                .read_seq_string = blkiocg_time_read,
+                .read_map = blkiocg_time_read,
+                .write_u64 = blkiocg_reset_write,
         },
         {
                 .name = "sectors",
-                .read_seq_string = blkiocg_sectors_read,
+                .read_map = blkiocg_sectors_read,
+                .write_u64 = blkiocg_reset_write,
+        },
+        {
+                .name = "io_service_bytes",
+                .read_map = blkiocg_io_service_bytes_read,
+                .write_u64 = blkiocg_reset_write,
+        },
+        {
+                .name = "io_serviced",
+                .read_map = blkiocg_io_serviced_read,
+                .write_u64 = blkiocg_reset_write,
+        },
+        {
+                .name = "io_service_time",
+                .read_map = blkiocg_io_service_time_read,
+                .write_u64 = blkiocg_reset_write,
+        },
+        {
+                .name = "io_wait_time",
+                .read_map = blkiocg_io_wait_time_read,
+                .write_u64 = blkiocg_reset_write,
         },
 #ifdef CONFIG_DEBUG_BLK_CGROUP
        {
                 .name = "dequeue",
-                .read_seq_string = blkiocg_dequeue_read,
+                .read_map = blkiocg_dequeue_read,
        },
 #endif
 };
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index fe445178f586..5c5e5294b506 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -23,6 +23,14 @@ extern struct cgroup_subsys blkio_subsys;
 #define blkio_subsys_id blkio_subsys.subsys_id
 #endif
 
+enum io_type {
+        IO_READ = 0,
+        IO_WRITE,
+        IO_SYNC,
+        IO_ASYNC,
+        IO_TYPE_MAX
+};
+
 struct blkio_cgroup {
         struct cgroup_subsys_state css;
         unsigned int weight;
@@ -30,6 +38,23 @@ struct blkio_cgroup {
         struct hlist_head blkg_list;
 };
 
+struct blkio_group_stats {
+        /* total disk time and nr sectors dispatched by this group */
+        uint64_t time;
+        uint64_t sectors;
+        /* Total disk time used by IOs in ns */
+        uint64_t io_service_time[IO_TYPE_MAX];
+        uint64_t io_service_bytes[IO_TYPE_MAX]; /* Total bytes transferred */
+        /* Total IOs serviced, post merge */
+        uint64_t io_serviced[IO_TYPE_MAX];
+        /* Total time spent waiting in scheduler queue in ns */
+        uint64_t io_wait_time[IO_TYPE_MAX];
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+        /* How many times this group has been removed from service tree */
+        unsigned long dequeue;
+#endif
+};
+
 struct blkio_group {
         /* An rcu protected unique identifier for the group */
         void *key;
@@ -38,15 +63,13 @@ struct blkio_group {
 #ifdef CONFIG_DEBUG_BLK_CGROUP
         /* Store cgroup path */
         char path[128];
-        /* How many times this group has been removed from service tree */
-        unsigned long dequeue;
 #endif
         /* The device MKDEV(major, minor), this group has been created for */
         dev_t   dev;
 
-        /* total disk time and nr sectors dispatched by this group */
-        unsigned long time;
-        unsigned long sectors;
+        /* Need to serialize the stats in the case of reset/update */
+        spinlock_t stats_lock;
+        struct blkio_group_stats stats;
 };
 
 typedef void (blkio_unlink_group_fn) (void *key, struct blkio_group *blkg);
@@ -105,8 +128,8 @@ extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
 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_blkio_group_stats(struct blkio_group *blkg,
-                                                unsigned long time);
+void blkiocg_update_timeslice_used(struct blkio_group *blkg,
+                                        unsigned long time);
 #else
 struct cgroup;
 static inline struct blkio_cgroup *
@@ -122,7 +145,7 @@ 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_blkio_group_stats(struct blkio_group *blkg,
+static inline void blkiocg_update_timeslice_used(struct blkio_group *blkg,
                                                 unsigned long time) {}
 #endif
 #endif /* _BLK_CGROUP_H */
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 7471d36bce89..c5161bbf2fe9 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -915,7 +915,7 @@ static void cfq_group_served(struct cfq_data *cfqd, struct cfq_group *cfqg,
 
         cfq_log_cfqg(cfqd, cfqg, "served: vt=%llu min_vt=%llu", cfqg->vdisktime,
                                         st->min_vdisktime);
-        blkiocg_update_blkio_group_stats(&cfqg->blkg, used_sl);
+        blkiocg_update_timeslice_used(&cfqg->blkg, used_sl);
 }
 
 #ifdef CONFIG_CFQ_GROUP_IOSCHED