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Date:   Fri, 25 Nov 2022 11:14:44 +0100
From:   Andreas Herrmann <aherrmann@suse.de>
To:     Li Nan <linan122@huawei.com>
Cc:     tj@kernel.org, josef@toxicpanda.com, axboe@kernel.dk,
        cgroups@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, yukuai3@huawei.com,
        yi.zhang@huawei.com
Subject: Re: [PATCH -next 2/2] blk-iocost: change div64_u64 to
 DIV64_U64_ROUND_UP in ioc_refresh_params()
Message-ID: <Y4CVlCgB5eSw03yI@suselix>
References: <20221124140635.695205-1-linan122@huawei.com>
 <20221124140635.695205-2-linan122@huawei.com>
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On Thu, Nov 24, 2022 at 10:06:35PM +0800, Li Nan wrote:
> vrate_min is calculated by DIV64_U64_ROUND_UP, but vrate_max is calculated
> by div64_u64. Vrate_min may be 1 greater than vrate_max if the input
> values min and max of cost.qos are equal.
> 
> Signed-off-by: Li Nan <linan122@huawei.com>
> ---
>  block/blk-iocost.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Andreas Herrmann <aherrmann@suse.de>

> diff --git a/block/blk-iocost.c b/block/blk-iocost.c
> index a38a5324bf10..9030ad8672f3 100644
> --- a/block/blk-iocost.c
> +++ b/block/blk-iocost.c
> @@ -926,7 +926,7 @@ static bool ioc_refresh_params(struct ioc *ioc, bool force)
>  
>  	ioc->vrate_min = DIV64_U64_ROUND_UP((u64)ioc->params.qos[QOS_MIN] *
>  					    VTIME_PER_USEC, MILLION);
> -	ioc->vrate_max = div64_u64((u64)ioc->params.qos[QOS_MAX] *
> +	ioc->vrate_max = DIV64_U64_ROUND_UP((u64)ioc->params.qos[QOS_MAX] *
>  				   VTIME_PER_USEC, MILLION);
>  
>  	return true;
> -- 
> 2.31.1
> 

-- 
Regards,
Andreas

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