Re: [PATCH v6 1/4] block: add task-context bio completion infrastructure

[Hillf Danton <hdanton@sina.com>]

On Thu, 14 May 2026 17:51:14 -0400 Tal Zussman wrote:
> +
> +static void bio_complete_work_fn(struct work_struct *w)
> +{
> +	struct delayed_work *dw = to_delayed_work(w);
> +	struct bio_complete_batch *batch =
> +		container_of(dw, struct bio_complete_batch, work);
> +
> +	while (1) {
> +		struct bio_list list;
> +		struct bio *bio;
> +
> +		local_lock_irq(&bio_complete_batch.lock);
> +		list = batch->list;
> +		bio_list_init(&batch->list);
> +		local_unlock_irq(&bio_complete_batch.lock);
> +
> +		if (bio_list_empty(&list))
> +			break;
> +
> +		while ((bio = bio_list_pop(&list)))
> +			bio->bi_end_io(bio);
> +
> +		if (need_resched()) {
> +			bool is_empty;
> +
Checking resched is not needed as workqueue worker can be preempted
while processing bios．Given batch and delayed work, I suspect completing
more than batch, the bios accumulated within a jiff, makes sense.

> +			local_lock_irq(&bio_complete_batch.lock);
> +			is_empty = bio_list_empty(&batch->list);
> +			local_unlock_irq(&bio_complete_batch.lock);
> +			if (!is_empty)
> +				mod_delayed_work_on(batch->cpu,
> +						    bio_complete_wq,
> +						    &batch->work, 0);
> +			break;
> +		}
> +	}
> +}
> +