From 6f42da2fc8aee833f4eeb5ad9cde6e7c79cd10d9 Mon Sep 17 00:00:00 2001 From: Markus Pargmann Date: Tue, 8 Dec 2015 10:39:25 +0100 Subject: log2: Add missing __rounddown_pow_of_two() Signed-off-by: Markus Pargmann Signed-off-by: Sascha Hauer --- include/linux/log2.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/include/linux/log2.h b/include/linux/log2.h index d9913f06bd..36519e3aa3 100644 --- a/include/linux/log2.h +++ b/include/linux/log2.h @@ -63,6 +63,15 @@ unsigned long __roundup_pow_of_two(unsigned long n) return 1UL << fls(n - 1); } +/* + * round down to nearest power of two + */ +static inline __attribute__((const)) +unsigned long __rounddown_pow_of_two(unsigned long n) +{ + return 1UL << (fls_long(n) - 1); +} + /** * ilog2 - log of base 2 of 32-bit or a 64-bit unsigned value * @n - parameter -- cgit v1.2.3