Edit File: __fls.h
#ifndef _ASM_GENERIC_BITOPS___FLS_H_ #define _ASM_GENERIC_BITOPS___FLS_H_ #include <asm/types.h> /** * __fls - find last (most-significant) set bit in a long word * @word: the word to search * * Undefined if no set bit exists, so code should check against 0 first. */ static __always_inline unsigned long __fls(unsigned long word) { int num = BITS_PER_LONG - 1; #if BITS_PER_LONG == 64 if (!(word & (~0ul << 32))) { num -= 32; word <<= 32; } #endif if (!(word & (~0ul << (BITS_PER_LONG-16)))) { num -= 16; word <<= 16; } if (!(word & (~0ul << (BITS_PER_LONG-8)))) { num -= 8; word <<= 8; } if (!(word & (~0ul << (BITS_PER_LONG-4)))) { num -= 4; word <<= 4; } if (!(word & (~0ul << (BITS_PER_LONG-2)))) { num -= 2; word <<= 2; } if (!(word & (~0ul << (BITS_PER_LONG-1)))) num -= 1; return num; } #endif /* _ASM_GENERIC_BITOPS___FLS_H_ */