Re: [PATCH v1 1/1] math.h: Document abs_diff()

From: Randy Dunlap
Date: Fri Aug 04 2023 - 01:27:42 EST




On 8/3/23 22:09, Andy Shevchenko wrote:
> Initially abs_diff() has lack of documentation. Add it.
>
> Suggested-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---
> include/linux/math.h | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/include/linux/math.h b/include/linux/math.h
> index 336e3e3678e7..dfba59b59998 100644
> --- a/include/linux/math.h
> +++ b/include/linux/math.h
> @@ -155,6 +155,18 @@ __STRUCT_FRACT(u32)
> __builtin_types_compatible_p(typeof(x), unsigned type), \
> ({ signed type __x = (x); __x < 0 ? -__x : __x; }), other)
>
> +/**
> + * abs_diff - return absolute value of the difference between the arguments
> + * @a: the first argument
> + * @b: the second argument
> + *
> + * @a and @b has to be of the same type. With this restriction we compare

Preferably s/has/have/.

> + * signed to signed and unsigned to unsigned. The result is the subtraction
> + * the smaller of the two from the bigger, hence result is always a positive
> + * value.
> + *
> + * Return: an absolute value of the difference between the @a and @b.
> + */
> #define abs_diff(a, b) ({ \
> typeof(a) __a = (a); \
> typeof(b) __b = (b); \

--
~Randy