From: Chunyan Zhang Date: Fri, 24 Jul 2020 12:21:47 +0000 (+0800) Subject: math64: New DIV_S64_ROUND_CLOSEST helper X-Git-Tag: v5.9-rc1~82^2~15 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=af60459a543483c5ad155a92daa8c3a6c00a0829;p=thirdparty%2Fkernel%2Flinux.git math64: New DIV_S64_ROUND_CLOSEST helper Provide DIV_S64_ROUND_CLOSEST helper which uses div_s64 to perform division rounded to the closest integer using signed 64bit dividend and signed 32bit divisor. Signed-off-by: Chunyan Zhang Signed-off-by: Sebastian Reichel --- diff --git a/include/linux/math64.h b/include/linux/math64.h index 11a267413e8e7..cd06939894367 100644 --- a/include/linux/math64.h +++ b/include/linux/math64.h @@ -279,4 +279,23 @@ static inline u64 mul_u64_u32_div(u64 a, u32 mul, u32 divisor) #define DIV64_U64_ROUND_CLOSEST(dividend, divisor) \ ({ u64 _tmp = (divisor); div64_u64((dividend) + _tmp / 2, _tmp); }) +/* + * DIV_S64_ROUND_CLOSEST - signed 64bit divide with 32bit divisor rounded to nearest integer + * @dividend: signed 64bit dividend + * @divisor: signed 32bit divisor + * + * Divide signed 64bit dividend by signed 32bit divisor + * and round to closest integer. + * + * Return: dividend / divisor rounded to nearest integer + */ +#define DIV_S64_ROUND_CLOSEST(dividend, divisor)( \ +{ \ + s64 __x = (dividend); \ + s32 __d = (divisor); \ + ((__x > 0) == (__d > 0)) ? \ + div_s64((__x + (__d / 2)), __d) : \ + div_s64((__x - (__d / 2)), __d); \ +} \ +) #endif /* _LINUX_MATH64_H */