linux-kernel - Re: [PATCH v10 06/11] math.h: Add macros for rounding to closest value

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Date: Fri, 31 May 2024 14:06:13 +0530
From: Devarsh Thakkar <devarsht@...com>
To: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
CC: <mchehab@...nel.org>, <hverkuil-cisco@...all.nl>,
        <linux-media@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        <benjamin.gaignard@...labora.com>, <sebastian.fricke@...labora.com>,
        <akpm@...ux-foundation.org>, <gregkh@...uxfoundation.org>,
        <adobriyan@...il.com>, <jani.nikula@...el.com>,
        <p.zabel@...gutronix.de>, <airlied@...il.com>, <daniel@...ll.ch>,
        <dri-devel@...ts.freedesktop.org>, <laurent.pinchart@...asonboard.com>,
        <praneeth@...com>, <nm@...com>, <vigneshr@...com>, <a-bhatia1@...com>,
        <j-luthra@...com>, <b-brnich@...com>, <detheridge@...com>,
        <p-mantena@...com>, <vijayp@...com>, <andrzej.p@...labora.com>,
        <nicolas@...fresne.ca>, <davidgow@...gle.com>, <dlatypov@...gle.com>
Subject: Re: [PATCH v10 06/11] math.h: Add macros for rounding to closest
 value

Hi Andy,

Thanks for the review.

On 31/05/24 00:49, Andy Shevchenko wrote:
> On Thu, May 30, 2024 at 10:42:25PM +0530, Devarsh Thakkar wrote:
>> Add below rounding related macros:
>>
>> round_closest_up(x, y) : Rounds x to closest multiple of y where y is a
>> power of 2, with a preference to round up in case two nearest values are
>> possible.
>>
>> round_closest_down(x, y) : Rounds x to closest multiple of y where y is a
>> power of 2, with a preference to round down in case two nearest values are
>> possible.
>>
>> roundclosest(x, y) : Rounds x to closest multiple of y, this macro should
>> generally be used only when y is not multiple of 2 as otherwise
>> round_closest* macros should be used which are much faster.
>>
>> Examples:
>>  * round_closest_up(17, 4) = 16
>>  * round_closest_up(15, 4) = 16
>>  * round_closest_up(14, 4) = 16
>>  * round_closest_down(17, 4) = 16
>>  * round_closest_down(15, 4) = 16
>>  * round_closest_down(14, 4) = 12
>>  * roundclosest(21, 5) = 20
>>  * roundclosest(19, 5) = 20
>>  * roundclosest(17, 5) = 15
> 
> ...
> 
>> + * Examples :
> 
> It's inconsistent with the other one below.
> 
>> + * 	round_closest_up(17, 4) = 16
>> + *
>> + * 	round_closest_up(15, 4) = 16
>> + *
>> + * 	round_closest_up(14, 4) = 16
> 
> The three have TABs/spaces mixture.
> 
> I believe you wanted:
> 
>  * Examples::
>  * * round_closest_up(17, 4) = 16
>  * * round_closest_up(15, 4) = 16
>  * * round_closest_up(14, 4) = 16
> 

I initially referred the style from this link [1] but probably missed to
remove extra space from my patch.

But what you suggested looks better, I will go with what you suggested.

[1]  https://elixir.bootlin.com/linux/v6.9/source/include/linux/int_log.h#L22

Regards
Devarsh