From 90933fc8ba5cc9034e3c04ee19938a22b0b4fe4e Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Wed, 21 Dec 2005 19:31:36 -0800 Subject: [FLS64]: x86_64 version Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- include/asm-x86_64/bitops.h | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) (limited to 'include/asm-x86_64/bitops.h') diff --git a/include/asm-x86_64/bitops.h b/include/asm-x86_64/bitops.h index 94b52c8ce97..a4d5d090945 100644 --- a/include/asm-x86_64/bitops.h +++ b/include/asm-x86_64/bitops.h @@ -340,6 +340,20 @@ static __inline__ unsigned long __ffs(unsigned long word) return word; } +/* + * __fls: find last bit set. + * @word: The word to search + * + * Undefined if no zero exists, so code should check against ~0UL first. + */ +static __inline__ unsigned long __fls(unsigned long word) +{ + __asm__("bsrq %1,%0" + :"=r" (word) + :"rm" (word)); + return word; +} + #ifdef __KERNEL__ static inline int sched_find_first_bit(const unsigned long *b) @@ -369,6 +383,19 @@ static __inline__ int ffs(int x) return r+1; } +/** + * fls64 - find last bit set in 64 bit word + * @x: the word to search + * + * This is defined the same way as fls. + */ +static __inline__ int fls64(__u64 x) +{ + if (x == 0) + return 0; + return __fls(x) + 1; +} + /** * hweightN - returns the hamming weight of a N-bit word * @x: the word to weigh @@ -409,7 +436,6 @@ static __inline__ int ffs(int x) /* find last set bit */ #define fls(x) generic_fls(x) -#define fls64(x) generic_fls64(x) #endif /* __KERNEL__ */ -- cgit v1.2.3-18-g5258