blkcg: add blkcg->id
Add 64bit unique id to blkcg. This will be used by policies which
want blkcg identity test to tell whether the associated blkcg has
changed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 9df5ab0..1cb8f76 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -116,6 +116,9 @@
unsigned int weight;
spinlock_t lock;
struct hlist_head blkg_list;
+
+ /* for policies to test whether associated blkcg has changed */
+ uint64_t id;
};
struct blkio_group_stats {