On Tue 21-12-21 11:21:33, Yu Kuai wrote:
> Moving bfqq to it's parent bfqg is pointless.
>
> Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
Did you notice that this is happening often enough that the check is worth
it? Where do we do this?
Honza
> ---
> block/bfq-cgroup.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
> index 24a5c5329bcd..0f62546a72d4 100644
> --- a/block/bfq-cgroup.c
> +++ b/block/bfq-cgroup.c
> @@ -645,6 +645,11 @@ void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq,
> struct bfq_group *bfqg)
> {
> struct bfq_entity *entity = &bfqq->entity;
> + struct bfq_group *old_parent = bfq_group(bfqq);
> +
> + /* No point to move bfqq to the same group */
> + if (old_parent == bfqg)
> + return;
>
> /*
> * Get extra reference to prevent bfqq from being freed in
> @@ -666,7 +671,7 @@ void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq,
> bfq_deactivate_bfqq(bfqd, bfqq, false, false);
> else if (entity->on_st_or_in_serv)
> bfq_put_idle_entity(bfq_entity_service_tree(entity), entity);
> - bfqg_and_blkg_put(bfqq_group(bfqq));
> + bfqg_and_blkg_put(old_parent);
>
> if (entity->parent &&
> entity->parent->last_bfqq_created == bfqq)
> --
> 2.31.1
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
