linux-kernel - Re: [PATCH] drm/radeon: replace min/max nesting with clamp()

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <0811e8e8-5990-4880-a2cc-f9bd6b3ec4bd@amd.com>
Date: Tue, 12 Aug 2025 08:49:07 +0200
From: Christian König <christian.koenig@....com>
To: Xichao Zhao <zhao.xichao@...o.com>, alexander.deucher@....com,
 airlied@...il.com, simona@...ll.ch
Cc: amd-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
 linux-kernel@...r.kernel.org
Subject: Re: [PATCH] drm/radeon: replace min/max nesting with clamp()

On 12.08.25 05:16, Xichao Zhao wrote:
> The clamp() macro explicitly expresses the intent of constraining
> a value within bounds.Therefore, replacing min(max(a, b), c) and
> max(min(a,b),c) with clamp(val, lo, hi) can improve code readability.
> 
> Signed-off-by: Xichao Zhao <zhao.xichao@...o.com>

Reviewed-by: Christian König <christian.koenig@....com>

> ---
>  drivers/gpu/drm/radeon/radeon_display.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c
> index b4bf5dfeea2d..d66c1a30df95 100644
> --- a/drivers/gpu/drm/radeon/radeon_display.c
> +++ b/drivers/gpu/drm/radeon/radeon_display.c
> @@ -926,10 +926,10 @@ static void avivo_get_fb_ref_div(unsigned nom, unsigned den, unsigned post_div,
>  				 unsigned *fb_div, unsigned *ref_div)
>  {
>  	/* limit reference * post divider to a maximum */
> -	ref_div_max = max(min(100 / post_div, ref_div_max), 1u);
> +	ref_div_max = clamp(100 / post_div, 1u, ref_div_max);
>  
>  	/* get matching reference and feedback divider */
> -	*ref_div = min(max(den/post_div, 1u), ref_div_max);
> +	*ref_div = clamp(den / post_div, 1u, ref_div_max);
>  	*fb_div = DIV_ROUND_CLOSEST(nom * *ref_div * post_div, den);
>  
>  	/* limit fb divider to its maximum */