blk-cgroup: fix missing pd_online_fn() while activating policy

If the policy defines pd_online_fn(), it should be called after
pd_init_fn(), like blkg_create().

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230103112833.2013432-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index ce6a2b7..4c94a65 100644 (file)
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1455,6 +1455,10 @@ retry:
                list_for_each_entry_reverse(blkg, &q->blkg_list, q_node)
                        pol->pd_init_fn(blkg->pd[pol->plid]);
 
+       if (pol->pd_online_fn)
+               list_for_each_entry_reverse(blkg, &q->blkg_list, q_node)
+                       pol->pd_online_fn(blkg->pd[pol->plid]);
+
        __set_bit(pol->plid, q->blkcg_pols);
        ret = 0;