Re: [PATCH] blk-mq: remove hybrid polling

[Jens Axboe <axboe@kernel.dk>]

> diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
> index f1fce1c7fa44b..c6c231f3d0f10 100644
> --- a/block/blk-sysfs.c
> +++ b/block/blk-sysfs.c
> @@ -408,36 +408,7 @@ queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count)
>  
>  static ssize_t queue_poll_delay_show(struct request_queue *q, char *page)
>  {
> -	int val;
> -
> -	if (q->poll_nsec == BLK_MQ_POLL_CLASSIC)
> -		val = BLK_MQ_POLL_CLASSIC;
> -	else
> -		val = q->poll_nsec / 1000;
> -
> -	return sprintf(page, "%d\n", val);
> -}
> -
> -static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page,
> -				size_t count)
> -{
> -	int err, val;
> -
> -	if (!q->mq_ops || !q->mq_ops->poll)
> -		return -EINVAL;
> -
> -	err = kstrtoint(page, 10, &val);
> -	if (err < 0)
> -		return err;
> -
> -	if (val == BLK_MQ_POLL_CLASSIC)
> -		q->poll_nsec = BLK_MQ_POLL_CLASSIC;
> -	else if (val >= 0)
> -		q->poll_nsec = val * 1000;
> -	else
> -		return -EINVAL;
> -
> -	return count;
> +	return sprintf(page, "%d\n", -1);
>  }

Do we want to retain the _store setting here to avoid breaking anything?
Yes, it won't do anything, but it's not like hybrid or classic poll had
differences that would be user visible (outside of perhaps using
different amounts of CPU).

Apart from that, not any major comments. Killing all of this (now)
unused code is great! Thanks for doing it.

-- 
Jens Axboe