blkio: Some debugging aids for CFQ

[safe/jmp/linux-2.6] / block / blk-cgroup.h

diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index cd50a2f..3573199 100644 (file)
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -27,12 +27,25 @@ struct blkio_group {
        void *key;
        struct hlist_node blkcg_node;
        unsigned short blkcg_id;
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+       /* Store cgroup path */
+       char path[128];
+#endif
 };
 
 #define BLKIO_WEIGHT_MIN       100
 #define BLKIO_WEIGHT_MAX       1000
 #define BLKIO_WEIGHT_DEFAULT   500
 
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+static inline char *blkg_path(struct blkio_group *blkg)
+{
+       return blkg->path;
+}
+#else
+static inline char *blkg_path(struct blkio_group *blkg) { return NULL; }
+#endif
+
 #ifdef CONFIG_BLK_CGROUP
 extern struct blkio_cgroup blkio_root_cgroup;
 extern struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup);