Re: [PATCH v2 2/6] block: Introduce the blk_rq_is_zoned_seq_write() function

[Damien Le Moal <damien.lemoal@opensource.wdc.com>]

On 6/24/22 08:25, Bart Van Assche wrote:
> Introduce a function that makes it easy to verify whether a write
> request is for a sequential write required or sequential write preferred
> zone. Simplify blk_req_needs_zone_write_lock() by using the new function.
> 
> Cc: Damien Le Moal <damien.lemoal@wdc.com>
> Signed-off-by: Bart Van Assche <bvanassche@acm.org>

Looks good.

Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

> ---
>  block/blk-zoned.c      | 14 +-------------
>  include/linux/blk-mq.h | 23 +++++++++++++++++++++++
>  2 files changed, 24 insertions(+), 13 deletions(-)
> 
> diff --git a/block/blk-zoned.c b/block/blk-zoned.c
> index 38cd840d8838..cafcbc508dfb 100644
> --- a/block/blk-zoned.c
> +++ b/block/blk-zoned.c
> @@ -57,19 +57,7 @@ EXPORT_SYMBOL_GPL(blk_zone_cond_str);
>   */
>  bool blk_req_needs_zone_write_lock(struct request *rq)
>  {
> -	if (!rq->q->seq_zones_wlock)
> -		return false;
> -
> -	if (blk_rq_is_passthrough(rq))
> -		return false;
> -
> -	switch (req_op(rq)) {
> -	case REQ_OP_WRITE_ZEROES:
> -	case REQ_OP_WRITE:
> -		return blk_rq_zone_is_seq(rq);
> -	default:
> -		return false;
> -	}
> +	return rq->q->seq_zones_wlock && blk_rq_is_zoned_seq_write(rq);
>  }
>  EXPORT_SYMBOL_GPL(blk_req_needs_zone_write_lock);
>  
> diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
> index 909d47e34b7c..d5930797b84d 100644
> --- a/include/linux/blk-mq.h
> +++ b/include/linux/blk-mq.h
> @@ -1136,6 +1136,24 @@ static inline unsigned int blk_rq_zone_is_seq(struct request *rq)
>  	return blk_queue_zone_is_seq(rq->q, blk_rq_pos(rq));
>  }
>  
> +/**
> + * blk_rq_is_zoned_seq_write() - Whether @rq is a write request for a sequential zone.
> + * @rq: Request to examine.
> + *
> + * In this context sequential zone means either a sequential write required or
> + * a sequential write preferred zone.
> + */
> +static inline bool blk_rq_is_zoned_seq_write(struct request *rq)
> +{
> +	switch (req_op(rq)) {
> +	case REQ_OP_WRITE:
> +	case REQ_OP_WRITE_ZEROES:
> +		return blk_rq_zone_is_seq(rq);
> +	default:
> +		return false;
> +	}
> +}
> +
>  bool blk_req_needs_zone_write_lock(struct request *rq);
>  bool blk_req_zone_write_trylock(struct request *rq);
>  void __blk_req_zone_write_lock(struct request *rq);
> @@ -1166,6 +1184,11 @@ static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
>  	return !blk_req_zone_is_write_locked(rq);
>  }
>  #else /* CONFIG_BLK_DEV_ZONED */
> +static inline bool blk_rq_is_zoned_seq_write(struct request *rq)
> +{
> +	return false;
> +}
> +
>  static inline bool blk_req_needs_zone_write_lock(struct request *rq)
>  {
>  	return false;


-- 
Damien Le Moal
Western Digital Research