Introduce min_array() (resp max_array()) in order to get the minimal (resp maximum) of values present in an array.
Signed-off-by: Herve Codina herve.codina@bootlin.com --- include/linux/minmax.h | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+)
diff --git a/include/linux/minmax.h b/include/linux/minmax.h index 396df1121bff..2cd0d34ce921 100644 --- a/include/linux/minmax.h +++ b/include/linux/minmax.h @@ -133,6 +133,42 @@ */ #define max_t(type, x, y) __careful_cmp((type)(x), (type)(y), >)
+/* + * Do not check the array parameter using __must_be_array(). + * In the following legit use-case where the "array" passed is a simple pointer, + * __must_be_array() will return a failure. + * --- 8< --- + * int *buff + * ... + * min = min_array(buff, nb_items); + * --- 8< --- + */ +#define __minmax_array(op, array, len) ({ \ + typeof(array) __array = (array); \ + typeof(len) __len = (len); \ + typeof(__array[0] + 0) __element = __array[--__len]; \ + 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