On Wed, 15 May 2024 10:30:59 -0400, Waiman Long wrote: > During a cgroup_rstat_flush() call, the lowest level of nodes are flushed > first before their parents. Since commit 3b8cc6298724 ("blk-cgroup: > Optimize blkcg_rstat_flush()"), iostat propagation was still done to > the parent. Grandparent, however, may not get the iostat update if the > parent has no blkg_iostat_set queued in its lhead lockless list. > > Fix this iostat propagation problem by queuing the parent's global > blkg->iostat into one of its percpu lockless lists to make sure that > the delta will always be propagated up to the grandparent and so on > toward the root blkcg. > > [...] Applied, thanks! [1/1] blk-cgroup: Properly propagate the iostat update up the hierarchy commit: 9d230c09964e6e18c8f6e4f0d41ee90eef45ec1c Best regards, -- Jens Axboe