diff options
Diffstat (limited to 'include/linux/log2.h')
| -rw-r--r-- | include/linux/log2.h | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/include/linux/log2.h b/include/linux/log2.h index 9f30d087a128..e17ceb32e0c9 100644 --- a/include/linux/log2.h +++ b/include/linux/log2.h @@ -41,10 +41,10 @@ int __ilog2_u64(u64 n) * *not* considered a power of two. * Return: true if @n is a power of 2, otherwise false. */ -static inline __attribute__((const)) +static __always_inline __attribute__((const)) bool is_power_of_2(unsigned long n) { - return (n != 0 && ((n & (n - 1)) == 0)); + return n - 1 < (n ^ (n - 1)); } /** @@ -255,4 +255,18 @@ int __bits_per(unsigned long n) ) : \ __bits_per(n) \ ) + +/** + * max_pow_of_two_factor - return highest power-of-2 factor + * @n: parameter + * + * find highest power-of-2 which is evenly divisible into n. + * 0 is returned for n == 0 or 1. + */ +static inline __attribute__((const)) +unsigned int max_pow_of_two_factor(unsigned int n) +{ + return n & -n; +} + #endif /* _LINUX_LOG2_H */ |