Re: [PATCH 5/5] blk-mq: Drop 'reserved' member of busy_tag_iter_fn

[Bart Van Assche <bvanassche@acm.org>]

On 6/17/22 03:55, John Garry wrote:
> We no longer use the 'reserved' member in for any iter function so it
                                         ^^^^^^
One of these two words probably should be removed.

> diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
> index 2dcd738c6952..b8cc8b41553f 100644
> --- a/block/blk-mq-tag.c
> +++ b/block/blk-mq-tag.c
> @@ -266,7 +266,6 @@ static bool bt_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
>   	struct blk_mq_hw_ctx *hctx = iter_data->hctx;
>   	struct request_queue *q = iter_data->q;
>   	struct blk_mq_tag_set *set = q->tag_set;
> -	bool reserved = iter_data->reserved;
>   	struct blk_mq_tags *tags;
>   	struct request *rq;
>   	bool ret = true;
> @@ -276,7 +275,7 @@ static bool bt_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
>   	else
>   		tags = hctx->tags;
>   
> -	if (!reserved)
> +	if (!iter_data->reserved)
>   		bitnr += tags->nr_reserved_tags;
>   	/*
>   	 * We can hit rq == NULL here, because the tagging functions

Is the above change really necessary?

> @@ -337,12 +336,11 @@ static bool bt_tags_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
>   {
>   	struct bt_tags_iter_data *iter_data = data;
>   	struct blk_mq_tags *tags = iter_data->tags;
> -	bool reserved = iter_data->flags & BT_TAG_ITER_RESERVED;
>   	struct request *rq;
>   	bool ret = true;
>   	bool iter_static_rqs = !!(iter_data->flags & BT_TAG_ITER_STATIC_RQS);
>   
> -	if (!reserved)
> +	if (!(iter_data->flags & BT_TAG_ITER_RESERVED))
>   		bitnr += tags->nr_reserved_tags;
>   
>   	/*

Same question here: is the above change really necessary?

Thanks,

Bart.