Re: [PATCH 5/6] blk-cgroup: reimplement basic IO stats using cgroup rstat

[Tejun Heo]

Hello,

Can you please see whether the following patch fixes the issue?

Thanks.

diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h
index 48a66738143d..19394c77ed99 100644
--- a/include/linux/blk-cgroup.h
+++ b/include/linux/blk-cgroup.h
@@ -626,7 +626,8 @@ static inline bool blkcg_bio_issue_check(struct request_queue *q,
 		bis->cur.ios[rwd]++;
 
 		u64_stats_update_end(&bis->sync);
-		cgroup_rstat_updated(blkg->blkcg->css.cgroup, cpu);
+		if (cgroup_subsys_on_dfl(io_cgrp_subsys))
+			cgroup_rstat_updated(blkg->blkcg->css.cgroup, cpu);
 		put_cpu();
 	}