| 1 | #ifndef FIO_FFZ_H |
| 2 | #define FIO_FFZ_H |
| 3 | |
| 4 | static inline int __ffs(unsigned long word) |
| 5 | { |
| 6 | int r = 0; |
| 7 | |
| 8 | #if BITS_PER_LONG == 64 |
| 9 | if ((word & 0xffffffff) == 0) { |
| 10 | r += 32; |
| 11 | word >>= 32; |
| 12 | } |
| 13 | #endif |
| 14 | if (!(word & 0xffff)) { |
| 15 | word >>= 16; |
| 16 | r += 16; |
| 17 | } |
| 18 | if (!(word & 0xff)) { |
| 19 | word >>= 8; |
| 20 | r += 8; |
| 21 | } |
| 22 | if (!(word & 0xf)) { |
| 23 | word >>= 4; |
| 24 | r += 4; |
| 25 | } |
| 26 | if (!(word & 3)) { |
| 27 | word >>= 2; |
| 28 | r += 2; |
| 29 | } |
| 30 | if (!(word & 1)) { |
| 31 | word >>= 1; |
| 32 | r += 1; |
| 33 | } |
| 34 | |
| 35 | return r; |
| 36 | } |
| 37 | |
| 38 | static inline int ffz(unsigned long bitmask) |
| 39 | { |
| 40 | return __ffs(~bitmask); |
| 41 | } |
| 42 | |
| 43 | #endif |