blkio: Export disk time and sectors used by a group to user space

o Export disk time and sector used by a group to user space through cgroup
  interface.

o Also export a "dequeue" interface to cgroup which keeps track of how many
  a times a group was deleted from service tree. Helps in debugging.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 20 insertions, 2 deletions

diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 3573199b298b..b24ab71db826 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -30,7 +30,15 @@ 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;
 };
 
 #define BLKIO_WEIGHT_MIN        100
@@ -42,24 +50,30 @@ static inline char *blkg_path(struct blkio_group *blkg)
 {
         return blkg->path;
 }
+void blkiocg_update_blkio_group_dequeue_stats(struct blkio_group *blkg,
+                                unsigned long dequeue);
 #else
 static inline char *blkg_path(struct blkio_group *blkg) { return NULL; }
+static inline void blkiocg_update_blkio_group_dequeue_stats(
+                        struct blkio_group *blkg, unsigned long dequeue) {}
 #endif
 
 #ifdef CONFIG_BLK_CGROUP
 extern struct blkio_cgroup blkio_root_cgroup;
 extern struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup);
 extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
-                                struct blkio_group *blkg, void *key);
+                        struct blkio_group *blkg, void *key, dev_t dev);
 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, unsigned long sectors);
 #else
 static inline struct blkio_cgroup *
 cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; }
 
 static inline void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
-                        struct blkio_group *blkg, void *key)
+                        struct blkio_group *blkg, void *key, dev_t dev)
 {
 }
 
@@ -68,5 +82,9 @@ 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_blkio_group_stats(struct blkio_group *blkg,
+                        unsigned long time, unsigned long sectors)
+{
+}
 #endif
 #endif /* _BLK_CGROUP_H */