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

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

[Andy Shevchenko]

Initially abs_diff() has lack of documentation. Add it.

Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 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
+ * 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);			\
-- 
2.40.0.1.gaa8946217a0b

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

[Randy Dunlap]

On 8/3/23 22:09, Andy Shevchenko wrote:
> Initially abs_diff() has lack of documentation. Add it.
> 
> Suggested-by: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  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

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

[Andy Shevchenko]

On Thu, Aug 03, 2023 at 10:23:48PM -0700, Randy Dunlap wrote:
> On 8/3/23 22:09, Andy Shevchenko wrote:

...

> > +/**
> > + * 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/.

Thank you! I fixed it locally, I hope Andrew can update this, but if needed
I will send a v2 with the proposed correction.

> > + * 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.
> > + */

-- 
With Best Regards,
Andy Shevchenko