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Message-ID: <f5e3a283-8f0a-12c0-94f0-19263bb3883d@acm.org>
Date:   Thu, 3 Aug 2023 10:01:10 -0700
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Subject: Re: [PATCH] block/mq-deadline: use correct way to throttling write
 requests
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To:     Zhiguo Niu <zhiguo.niu@unisoc.com>, axboe@kernel.dk
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        niuzhiguo84@gmail.com, hongyu.jin@unisoc.com,
        yunlong.xing@unisoc.com
References: <1691061162-22898-1-git-send-email-zhiguo.niu@unisoc.com>
From:   Bart Van Assche <bvanassche@acm.org>
In-Reply-To: <1691061162-22898-1-git-send-email-zhiguo.niu@unisoc.com>
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On 8/3/23 04:12, Zhiguo Niu wrote:
> diff --git a/block/mq-deadline.c b/block/mq-deadline.c
> index 5839a027e0f0..7e043d4a78f8 100644
> --- a/block/mq-deadline.c
> +++ b/block/mq-deadline.c
> @@ -620,8 +620,9 @@ static void dd_depth_updated(struct blk_mq_hw_ctx *hctx)
>   	struct request_queue *q = hctx->queue;
>   	struct deadline_data *dd = q->elevator->elevator_data;
>   	struct blk_mq_tags *tags = hctx->sched_tags;
> +	unsigned int shift = tags->bitmap_tags.sb.shift;
>   
> -	dd->async_depth = max(1UL, 3 * q->nr_requests / 4);
> +	dd->async_depth = max(1U, 3 * (1U << shift)  / 4);
>   
>   	sbitmap_queue_min_shallow_depth(&tags->bitmap_tags, dd->async_depth);
>   }

Reviewed-by: Bart Van Assche <bvanassche@acm.org>