1 #ifndef FIO_RAND_H 2 #define FIO_RAND_H 3 4 #include <inttypes.h> 5 #include <assert.h> 6 #include "types.h" 7 #include "../arch/arch.h" 8 9 #define FRAND32_MAX (-1U) 10 #define FRAND64_MAX (-1ULL) 11 12 struct taus88_state { 13 unsigned int s1, s2, s3; 14 }; 15 16 struct taus258_state { 17 uint64_t s1, s2, s3, s4, s5; 18 }; 19 20 struct frand_state { 21 unsigned int use64; 22 union { 23 struct taus88_state state32; 24 struct taus258_state state64; 25 }; 26 }; 27 28 static inline uint64_t rand_max(struct frand_state *state) 29 { 30 if (state->use64) 31 return FRAND64_MAX; 32 else 33 return FRAND32_MAX; 34 } 35 36 static inline void __frand32_copy(struct taus88_state *dst, 37 struct taus88_state *src) 38 { 39 dst->s1 = src->s1; 40 dst->s2 = src->s2; 41 dst->s3 = src->s3; 42 } 43 44 static inline void __frand64_copy(struct taus258_state *dst, 45 struct taus258_state *src) 46 { 47 dst->s1 = src->s1; 48 dst->s2 = src->s2; 49 dst->s3 = src->s3; 50 dst->s4 = src->s4; 51 dst->s5 = src->s5; 52 } 53 54 static inline void frand_copy(struct frand_state *dst, struct frand_state *src) 55 { 56 if (src->use64) 57 __frand64_copy(&dst->state64, &src->state64); 58 else 59 __frand32_copy(&dst->state32, &src->state32); 60 61 dst->use64 = src->use64; 62 } 63 64 static inline unsigned int __rand32(struct taus88_state *state) 65 { 66 #define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b) 67 68 state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12); 69 state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4); 70 state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17); 71 72 return (state->s1 ^ state->s2 ^ state->s3); 73 } 74 75 static inline uint64_t __rand64(struct taus258_state *state) 76 { 77 uint64_t xval; 78 79 xval = ((state->s1 << 1) ^ state->s1) >> 53; 80 state->s1 = ((state->s1 & 18446744073709551614ULL) << 10) ^ xval; 81 82 xval = ((state->s2 << 24) ^ state->s2) >> 50; 83 state->s2 = ((state->s2 & 18446744073709551104ULL) << 5) ^ xval; 84 85 xval = ((state->s3 << 3) ^ state->s3) >> 23; 86 state->s3 = ((state->s3 & 18446744073709547520ULL) << 29) ^ xval; 87 88 xval = ((state->s4 << 5) ^ state->s4) >> 24; 89 state->s4 = ((state->s4 & 18446744073709420544ULL) << 23) ^ xval; 90 91 xval = ((state->s5 << 3) ^ state->s5) >> 33; 92 state->s5 = ((state->s5 & 18446744073701163008ULL) << 8) ^ xval; 93 94 return (state->s1 ^ state->s2 ^ state->s3 ^ state->s4 ^ state->s5); 95 } 96 97 static inline uint64_t __rand(struct frand_state *state) 98 { 99 if (state->use64) 100 return __rand64(&state->state64); 101 else 102 return __rand32(&state->state32); 103 } 104 105 static inline double __rand_0_1(struct frand_state *state) 106 { 107 if (state->use64) { 108 uint64_t val = __rand64(&state->state64); 109 110 return (val + 1.0) / (FRAND64_MAX + 1.0); 111 } else { 112 uint32_t val = __rand32(&state->state32); 113 114 return (val + 1.0) / (FRAND32_MAX + 1.0); 115 } 116 } 117 118 /* 119 * Generate a random value between 'start' and 'end', both inclusive 120 */ 121 static inline int rand32_between(struct frand_state *state, int start, int end) 122 { 123 uint32_t r; 124 125 assert(!state->use64); 126 127 r = __rand32(&state->state32); 128 return start + (int) ((double)end * (r / (FRAND32_MAX + 1.0))); 129 } 130 131 extern void init_rand(struct frand_state *, bool); 132 extern void init_rand_seed(struct frand_state *, unsigned int seed, bool); 133 extern void __fill_random_buf(void *buf, unsigned int len, unsigned long seed); 134 extern unsigned long fill_random_buf(struct frand_state *, void *buf, unsigned int len); 135 extern void __fill_random_buf_percentage(unsigned long, void *, unsigned int, unsigned int, unsigned int, char *, unsigned int); 136 extern unsigned long fill_random_buf_percentage(struct frand_state *, void *, unsigned int, unsigned int, unsigned int, char *, unsigned int); 137 138 #endif 139
