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Sender: Tejun Heo <htejun@gmail.com>
Date: Fri, 12 Apr 2024 08:11:04 -1000
From: Tejun Heo <tj@kernel.org>
To: Yu Kuai <yukuai1@huaweicloud.com>
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Subject: Re: [PATCH RFC v2 6/6] blk-throtl: switch to use rq_qos
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References: <20240406080059.2248314-1-yukuai1@huaweicloud.com>
 <20240406080059.2248314-7-yukuai1@huaweicloud.com>
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In-Reply-To: <20240406080059.2248314-7-yukuai1@huaweicloud.com>

Hello,

On Sat, Apr 06, 2024 at 04:00:59PM +0800, Yu Kuai wrote:
> From: Yu Kuai <yukuai3@huawei.com>
> 
> To avoid exposing blk-throttle internal implementation to general block
> layer.
..
> @@ -832,7 +832,7 @@ void submit_bio_noacct(struct bio *bio)
>  		goto not_supported;
>  	}
>  
> -	if (blk_throtl_bio(bio))
> +	if (rq_qos_throttle_bio(q, bio))
>  		return;
>  	submit_bio_noacct_nocheck(bio);
>  	return;

This is a half-way conversion, right? You're adding a dedicated hook to
rq_qos and none of the other hooks can be used by blk-throtl. Even the name,
rq_qos_throttle_bio(), becomes a misnomer. I'm not really sure this makes
things better or worse. It makes certain things a bit cleaner but other
things nastier. I don't know.

Thanks.

-- 
tejun