Re: [PATCH v3 06/12] minmax: Introduce {min,max}_array()

[Andy Shevchenko]

On Mon, Jun 12, 2023 at 3:30 PM Herve Codina <herve.codina@xxxxxxxxxxx> wrote:
>
> Introduce min_array() (resp max_array()) in order to get the
> minimal (resp maximum) of values present in an array.

Some comments below, after addressing them,
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>

> Signed-off-by: Herve Codina <herve.codina@xxxxxxxxxxx>
> ---
>  include/linux/minmax.h | 26 ++++++++++++++++++++++++++
>  1 file changed, 26 insertions(+)
>
> diff --git a/include/linux/minmax.h b/include/linux/minmax.h
> index 396df1121bff..37a211f22404 100644
> --- a/include/linux/minmax.h
> +++ b/include/linux/minmax.h
> @@ -133,6 +133,32 @@
>   */
>  #define max_t(type, x, y)      __careful_cmp((type)(x), (type)(y), >)
>
> +#define __minmax_array(op, array, len) ({                      \

Maybe it's my MUA, maybe the code contains spaces, can you switch to
TABs if it's the case?

> +       typeof(array) __array = (array);                        \

We have __must_be_array()

You will need to fix the inclusions in minmax.h at the same time, it needs
linux/build_bug.h (which includes compiler.h needed for __UNIQUE_ID()
and for the above mentioned one).

> +       typeof(len) __len = (len);                              \
> +       typeof(*__array + 0) __element = __array[--__len];      \

After above, this can be written as __array[0].

> +       while (__len--)                                         \
> +               __element = op(__element, __array[__len]);      \
> +       __element; })
> +
> +/**
> + * min_array - return minimum of values present in an array
> + * @array: array
> + * @len: array length
> + *
> + * Note that @len must not be zero (empty array).
> + */
> +#define min_array(array, len) __minmax_array(min, array, len)
> +
> +/**
> + * max_array - return maximum of values present in an array
> + * @array: array
> + * @len: array length
> + *
> + * Note that @len must not be zero (empty array).
> + */
> +#define max_array(array, len) __minmax_array(max, array, len)
> +
>  /**
>   * clamp_t - return a value clamped to a given range using a given type
>   * @type: the type of variable to use

-- 
With Best Regards,
Andy Shevchenko