linux-kernel - Re: [PATCH v4 1/1] drm/i915: Move abs

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

Message-Id: <20230803102446.8edf94acc77e81ab2e09cee3@linux-foundation.org>
Date:   Thu, 3 Aug 2023 10:24:46 -0700
From:   Andrew Morton <akpm@...ux-foundation.org>
To:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Cc:     Jani Nikula <jani.nikula@...el.com>,
        Imre Deak <imre.deak@...el.com>,
        Philipp Zabel <p.zabel@...gutronix.de>,
        Andi Shyti <andi.shyti@...ux.intel.com>,
        Jiri Slaby <jirislaby@...nel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Alexey Dobriyan <adobriyan@...il.com>,
        intel-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
        linux-kernel@...r.kernel.org, linux-serial@...r.kernel.org,
        linux-fbdev@...r.kernel.org,
        Jani Nikula <jani.nikula@...ux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@...el.com>,
        Tvrtko Ursulin <tvrtko.ursulin@...ux.intel.com>,
        David Airlie <airlied@...il.com>,
        Daniel Vetter <daniel@...ll.ch>, Helge Deller <deller@....de>,
        Rasmus Villemoes <linux@...musvillemoes.dk>
Subject: Re: [PATCH v4 1/1] drm/i915: Move abs_diff() to math.h

On Thu,  3 Aug 2023 16:19:18 +0300 Andy Shevchenko <andriy.shevchenko@...ux.intel.com> wrote:

> abs_diff() belongs to math.h. Move it there.
> This will allow others to use it.
> 
> ...
>
> --- a/include/linux/math.h
> +++ b/include/linux/math.h
> @@ -155,6 +155,13 @@ __STRUCT_FRACT(u32)
>  	__builtin_types_compatible_p(typeof(x), unsigned type),		\
>  	({ signed type __x = (x); __x < 0 ? -__x : __x; }), other)
>  
> +#define abs_diff(a, b) ({			\
> +	typeof(a) __a = (a);			\
> +	typeof(b) __b = (b);			\
> +	(void)(&__a == &__b);			\
> +	__a > __b ? (__a - __b) : (__b - __a);	\
> +})

Can we document it please?

Also, the open-coded type comparison could be replaced with __typecheck()?

And why the heck isn't __typecheck() in typecheck.h, to be included by
minmax.h.

etcetera.  Sigh.  I'll grab it, but please at least send along some
kerneldoc?