On Thu, Apr 10, 2025 at 09:30:17PM +0800, Ming Lei wrote:
> @@ -5071,9 +4984,15 @@ static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set,
> blk_mq_debugfs_register_hctxs(q);
> }
>
> -switch_back:
> - list_for_each_entry(q, &set->tag_list, tag_set_list)
> - blk_mq_elv_switch_back(&head, q);
> + list_for_each_entry(q, &set->tag_list, tag_set_list) {
> + const char *name = "none";
> +
> + mutex_lock(&q->elevator_lock);
> + if (q->elevator && !blk_queue_dying(q))
> + name = q->elevator->type->elevator_name;
> + __elevator_change(q, name, true);
> + mutex_unlock(&q->elevator_lock);
> + }
Coming back to this after looking through the next patches.
Why do we even need the __elevator_change call here? We've not
actually disabled the elevator, and we prevent other callers
from changing it.
As you pass in the force argument this now always calls
elevator_switch and thus blk_mq_init_sched. But why?
