Re: [PATCH 01/16] blk-mq-sched: add new parameter nr_requests in blk_mq_alloc_sched_tags()

[Yu Kuai]

Hi,

在 2025/08/14 16:16, Ming Lei 写道:
> >   struct elevator_tags *blk_mq_alloc_sched_tags(struct blk_mq_tag_set *set,
> > -		unsigned int nr_hw_queues)
> > +		unsigned int nr_hw_queues, unsigned int nr_requests)
> >   {
> >   	unsigned int nr_tags;
> >   	int i;
> > @@ -475,8 +475,11 @@ struct elevator_tags *blk_mq_alloc_sched_tags(struct blk_mq_tag_set *set,
> >   	 * 128, since we don't split into sync/async like the old code
> >   	 * did. Additionally, this is a per-hw queue depth.
> >   	 */
> > -	et->nr_requests = 2 * min_t(unsigned int, set->queue_depth,
> > -			BLKDEV_DEFAULT_RQ);
> > +	if (nr_requests)
> > +		et->nr_requests = nr_requests;
> > +	else
> > +		et->nr_requests = 2 * min_t(unsigned int, set->queue_depth,
> > +				BLKDEV_DEFAULT_RQ);
> It looks more readable to add helper blk_mq_default_nr_requests(),
> and pass it from call sites directly, then people won't be confused
> with the passed zero `nr_requests`.

Yes, this sounds good.

Thanks for the review,
Kuai