[fio.git] / lib / rand.h

#ifndef FIO_RAND_H
#define FIO_RAND_H

#include <inttypes.h>
#include <assert.h>
#include "types.h"
#include "../arch/arch.h"

#define FRAND32_MAX	(-1U)
#define FRAND64_MAX	(-1ULL)

struct taus88_state {
	unsigned int s1, s2, s3;
};

struct taus258_state {
	uint64_t s1, s2, s3, s4, s5;
};

struct frand_state {
	unsigned int use64;
	union {
		struct taus88_state state32;
		struct taus258_state state64;
	};
};

static inline uint64_t rand_max(struct frand_state *state)
{
	if (state->use64)
		return FRAND64_MAX;
	else
		return FRAND32_MAX;
}

static inline void __frand32_copy(struct taus88_state *dst,
				  struct taus88_state *src)
{
	dst->s1 = src->s1;
	dst->s2 = src->s2;
	dst->s3 = src->s3;
}

static inline void __frand64_copy(struct taus258_state *dst,
				  struct taus258_state *src)
{
	dst->s1 = src->s1;
	dst->s2 = src->s2;
	dst->s3 = src->s3;
	dst->s4 = src->s4;
	dst->s5 = src->s5;
}

static inline void frand_copy(struct frand_state *dst, struct frand_state *src)
{
	if (src->use64)
		__frand64_copy(&dst->state64, &src->state64);
	else
		__frand32_copy(&dst->state32, &src->state32);

	dst->use64 = src->use64;
}

static inline unsigned int __rand32(struct taus88_state *state)
{
#define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b)

	state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12);
	state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4);
	state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17);

	return (state->s1 ^ state->s2 ^ state->s3);
}

static inline uint64_t __rand64(struct taus258_state *state)
{
	uint64_t xval;

	xval = ((state->s1 <<  1) ^ state->s1) >> 53;
	state->s1 = ((state->s1 & 18446744073709551614ULL) << 10) ^ xval;

	xval = ((state->s2 << 24) ^ state->s2) >> 50;
	state->s2 = ((state->s2 & 18446744073709551104ULL) <<  5) ^ xval;

	xval = ((state->s3 <<  3) ^ state->s3) >> 23;
	state->s3 = ((state->s3 & 18446744073709547520ULL) << 29) ^ xval;

	xval = ((state->s4 <<  5) ^ state->s4) >> 24;
	state->s4 = ((state->s4 & 18446744073709420544ULL) << 23) ^ xval;

	xval = ((state->s5 <<  3) ^ state->s5) >> 33;
	state->s5 = ((state->s5 & 18446744073701163008ULL) <<  8) ^ xval;

	return (state->s1 ^ state->s2 ^ state->s3 ^ state->s4 ^ state->s5);
}

static inline uint64_t __rand(struct frand_state *state)
{
	if (state->use64)
		return __rand64(&state->state64);
	else
		return __rand32(&state->state32);
}

static inline double __rand_0_1(struct frand_state *state)
{
	if (state->use64) {
		uint64_t val = __rand64(&state->state64);

		return (val + 1.0) / (FRAND64_MAX + 1.0);
	} else {
		uint32_t val = __rand32(&state->state32);

		return (val + 1.0) / (FRAND32_MAX + 1.0);
	}
}

/*
 * Generate a random value between 'start' and 'end', both inclusive
 */
static inline int rand32_between(struct frand_state *state, int start, int end)
{
	uint32_t r;

	assert(!state->use64);

	r = __rand32(&state->state32);
	return start + (int) ((double)end * (r / (FRAND32_MAX + 1.0)));
}

extern void init_rand(struct frand_state *, bool);
extern void init_rand_seed(struct frand_state *, unsigned int seed, bool);
extern void __fill_random_buf(void *buf, unsigned int len, unsigned long seed);
extern unsigned long fill_random_buf(struct frand_state *, void *buf, unsigned int len);
extern void __fill_random_buf_percentage(unsigned long, void *, unsigned int, unsigned int, unsigned int, char *, unsigned int);
extern unsigned long fill_random_buf_percentage(struct frand_state *, void *, unsigned int, unsigned int, unsigned int, char *, unsigned int);

#endif
Commit	Line	Data
1fbbf72e JA	1	#ifndef FIO_RAND_H
	2	#define FIO_RAND_H
	3
c3546b53	4	#include <inttypes.h>
36dd3379	5	#include <assert.h>
de4096e8	6	#include "types.h"
16dc0710 JA	7	#include "../arch/arch.h"
16dc0710 JA	8
c3546b53 JA	9	#define FRAND32_MAX (-1U)
c3546b53 JA	10	#define FRAND64_MAX (-1ULL)
2615cc4b	11
c3546b53	12	struct taus88_state {
1fbbf72e JA	13	unsigned int s1, s2, s3;
	14	};
	15
c3546b53 JA	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
c3546b53 JA	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)
5c94b008 JA	46	{
	47	dst->s1 = src->s1;
	48	dst->s2 = src->s2;
	49	dst->s3 = src->s3;
c3546b53 JA	50	dst->s4 = src->s4;
c3546b53 JA	51	dst->s5 = src->s5;
5c94b008 JA	52	}
5c94b008 JA	53
c3546b53 JA	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)
1fbbf72e JA	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
c3546b53 JA	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
e7b24047 JA	105	static inline double __rand_0_1(struct frand_state *state)
	106	{
	107	if (state->use64) {
	108	uint64_t val = __rand64(&state->state64);
	109
592bf458	110	return (val + 1.0) / (FRAND64_MAX + 1.0);
e7b24047 JA	111	} else {
	112	uint32_t val = __rand32(&state->state32);
	113
592bf458	114	return (val + 1.0) / (FRAND32_MAX + 1.0);
e7b24047 JA	115	}
	116	}
	117
e0a04ac1 JA	118	/*
	119	* Generate a random value between 'start' and 'end', both inclusive
	120	*/
36dd3379	121	static inline int rand32_between(struct frand_state *state, int start, int end)
e0a04ac1	122	{
36dd3379 JA	123	uint32_t r;
	124
	125	assert(!state->use64);
e0a04ac1	126
36dd3379 JA	127	r = __rand32(&state->state32);
36dd3379 JA	128	return start + (int) ((double)end * (r / (FRAND32_MAX + 1.0)));
e0a04ac1 JA	129	}
e0a04ac1 JA	130
de4096e8 JA	131	extern void init_rand(struct frand_state *, bool);
de4096e8 JA	132	extern void init_rand_seed(struct frand_state *, unsigned int seed, bool);
7d9fb455	133	extern void __fill_random_buf(void *buf, unsigned int len, unsigned long seed);
3545a109	134	extern unsigned long fill_random_buf(struct frand_state , void buf, unsigned int len);
bc769898	135	extern void __fill_random_buf_percentage(unsigned long, void , unsigned int, unsigned int, unsigned int, char , unsigned int);
d1af2894	136	extern unsigned long fill_random_buf_percentage(struct frand_state , void , unsigned int, unsigned int, unsigned int, char *, unsigned int);
1fbbf72e JA	137
1fbbf72e JA	138	#endif