diff options
| -rw-r--r-- | tools/include/linux/log2.h | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/tools/include/linux/log2.h b/tools/include/linux/log2.h index 990b138..4144666 100644 --- a/tools/include/linux/log2.h +++ b/tools/include/linux/log2.h @@ -48,6 +48,15 @@ bool is_power_of_2(unsigned long n) } /* + * round up to nearest power of two + */ +static inline __attribute__((const)) +unsigned long __roundup_pow_of_two(unsigned long n) +{ + return 1UL << fls_long(n - 1); +} + +/* * round down to nearest power of two */ static inline __attribute__((const)) @@ -141,6 +150,22 @@ unsigned long __rounddown_pow_of_two(unsigned long n) __ilog2_u64(n) \ ) +/** + * roundup_pow_of_two - round the given value up to nearest power of two + * @n - parameter + * + * round the given value up to the nearest power of two + * - the result is undefined when n == 0 + * - this can be used to initialise global variables from constant data + */ +#define roundup_pow_of_two(n) \ +( \ + __builtin_constant_p(n) ? ( \ + (n == 1) ? 1 : \ + (1UL << (ilog2((n) - 1) + 1)) \ + ) : \ + __roundup_pow_of_two(n) \ + ) /** * rounddown_pow_of_two - round the given value down to nearest power of two |