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| author | Alexander van Heukelum <heukelum@mailshack.com> | 2008-03-15 18:32:36 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-04-26 19:21:16 +0200 |
| commit | d57594c203b1e7b54373080a797f0cbfa4aade68 (patch) | |
| tree | 61610af68fc93280fb0be00a4f1b523715bef3db | |
| parent | 56a6b1eb7bfb5ace0b5cb9c149f502fbd101b8ab (diff) | |
| download | lwn-d57594c203b1e7b54373080a797f0cbfa4aade68.tar.gz lwn-d57594c203b1e7b54373080a797f0cbfa4aade68.zip | |
bitops: use __fls for fls64 on 64-bit archs
Use __fls for fls64 on 64-bit archs. The implementation for
64-bit archs is moved from x86_64 to asm-generic.
Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | include/asm-generic/bitops/fls64.h | 22 | ||||
| -rw-r--r-- | include/asm-x86/bitops_64.h | 15 |
2 files changed, 24 insertions, 13 deletions
diff --git a/include/asm-generic/bitops/fls64.h b/include/asm-generic/bitops/fls64.h index 1b6b17ce2428..86d403f8b256 100644 --- a/include/asm-generic/bitops/fls64.h +++ b/include/asm-generic/bitops/fls64.h @@ -3,6 +3,18 @@ #include <asm/types.h> +/** + * fls64 - find last set bit in a 64-bit word + * @x: the word to search + * + * This is defined in a similar way as the libc and compiler builtin + * ffsll, but returns the position of the most significant set bit. + * + * fls64(value) returns 0 if value is 0 or the position of the last + * set bit if value is nonzero. The last (most significant) bit is + * at position 64. + */ +#if BITS_PER_LONG == 32 static inline int fls64(__u64 x) { __u32 h = x >> 32; @@ -10,5 +22,15 @@ static inline int fls64(__u64 x) return fls(h) + 32; return fls(x); } +#elif BITS_PER_LONG == 64 +static inline int fls64(__u64 x) +{ + if (x == 0) + return 0; + return __fls(x) + 1; +} +#else +#error BITS_PER_LONG not 32 or 64 +#endif #endif /* _ASM_GENERIC_BITOPS_FLS64_H_ */ diff --git a/include/asm-x86/bitops_64.h b/include/asm-x86/bitops_64.h index a5fbe7a02a3f..d13352087191 100644 --- a/include/asm-x86/bitops_64.h +++ b/include/asm-x86/bitops_64.h @@ -39,25 +39,14 @@ static inline void set_bit_string(unsigned long *bitmap, unsigned long i, #include <asm-generic/bitops/sched.h> -/** - * 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; -} - #define ARCH_HAS_FAST_MULTIPLIER 1 #include <asm-generic/bitops/hweight.h> #endif /* __KERNEL__ */ +#include <asm-generic/bitops/fls64.h> + #ifdef __KERNEL__ #include <asm-generic/bitops/ext2-non-atomic.h> |