[fio.git] / lib / rand.h

#ifndef FIO_RAND_H
#define FIO_RAND_H

#include <inttypes.h>
#include <assert.h>
#include "types.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);
	}
}

static inline uint32_t rand32_upto(struct frand_state *state, uint32_t end)
{
	uint32_t r;

	assert(!state->use64);

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

static inline uint64_t rand64_upto(struct frand_state *state, uint64_t end)
{
	uint64_t r;

	assert(state->use64);

	r = __rand64(&state->state64);
	end++;
	return (uint64_t) ((double)end * (r / (FRAND64_MAX + 1.0)));
}

/*
 * Generate a random value between 'start' and 'end', both inclusive
 */
static inline uint64_t rand_between(struct frand_state *state, uint64_t start,
				    uint64_t end)
{
	if (state->use64)
		return start + rand64_upto(state, end - start);
	else
		return start + rand32_upto(state, end - start);
}

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	7
c3546b53 JA	8	#define FRAND32_MAX (-1U)
c3546b53 JA	9	#define FRAND64_MAX (-1ULL)
2615cc4b	10
c3546b53	11	struct taus88_state {
1fbbf72e JA	12	unsigned int s1, s2, s3;
	13	};
	14
c3546b53 JA	15	struct taus258_state {
	16	uint64_t s1, s2, s3, s4, s5;
	17	};
	18
	19	struct frand_state {
	20	unsigned int use64;
	21	union {
	22	struct taus88_state state32;
	23	struct taus258_state state64;
	24	};
	25	};
	26
c3546b53 JA	27	static inline uint64_t rand_max(struct frand_state *state)
	28	{
	29	if (state->use64)
	30	return FRAND64_MAX;
	31	else
	32	return FRAND32_MAX;
	33	}
	34
	35	static inline void __frand32_copy(struct taus88_state *dst,
	36	struct taus88_state *src)
	37	{
	38	dst->s1 = src->s1;
	39	dst->s2 = src->s2;
	40	dst->s3 = src->s3;
	41	}
	42
	43	static inline void __frand64_copy(struct taus258_state *dst,
	44	struct taus258_state *src)
5c94b008 JA	45	{
	46	dst->s1 = src->s1;
	47	dst->s2 = src->s2;
	48	dst->s3 = src->s3;
c3546b53 JA	49	dst->s4 = src->s4;
c3546b53 JA	50	dst->s5 = src->s5;
5c94b008 JA	51	}
5c94b008 JA	52
c3546b53 JA	53	static inline void frand_copy(struct frand_state dst, struct frand_state src)
	54	{
	55	if (src->use64)
	56	__frand64_copy(&dst->state64, &src->state64);
	57	else
	58	__frand32_copy(&dst->state32, &src->state32);
	59
	60	dst->use64 = src->use64;
	61	}
	62
	63	static inline unsigned int __rand32(struct taus88_state *state)
1fbbf72e JA	64	{
	65	#define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b)
	66
	67	state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12);
	68	state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4);
	69	state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17);
	70
	71	return (state->s1 ^ state->s2 ^ state->s3);
	72	}
	73
c3546b53 JA	74	static inline uint64_t __rand64(struct taus258_state *state)
	75	{
	76	uint64_t xval;
	77
	78	xval = ((state->s1 << 1) ^ state->s1) >> 53;
	79	state->s1 = ((state->s1 & 18446744073709551614ULL) << 10) ^ xval;
	80
	81	xval = ((state->s2 << 24) ^ state->s2) >> 50;
	82	state->s2 = ((state->s2 & 18446744073709551104ULL) << 5) ^ xval;
	83
	84	xval = ((state->s3 << 3) ^ state->s3) >> 23;
	85	state->s3 = ((state->s3 & 18446744073709547520ULL) << 29) ^ xval;
	86
	87	xval = ((state->s4 << 5) ^ state->s4) >> 24;
	88	state->s4 = ((state->s4 & 18446744073709420544ULL) << 23) ^ xval;
	89
	90	xval = ((state->s5 << 3) ^ state->s5) >> 33;
	91	state->s5 = ((state->s5 & 18446744073701163008ULL) << 8) ^ xval;
	92
	93	return (state->s1 ^ state->s2 ^ state->s3 ^ state->s4 ^ state->s5);
	94	}
	95
	96	static inline uint64_t __rand(struct frand_state *state)
	97	{
	98	if (state->use64)
	99	return __rand64(&state->state64);
	100	else
	101	return __rand32(&state->state32);
	102	}
	103
e7b24047 JA	104	static inline double __rand_0_1(struct frand_state *state)
	105	{
	106	if (state->use64) {
	107	uint64_t val = __rand64(&state->state64);
	108
592bf458	109	return (val + 1.0) / (FRAND64_MAX + 1.0);
e7b24047 JA	110	} else {
	111	uint32_t val = __rand32(&state->state32);
	112
592bf458	113	return (val + 1.0) / (FRAND32_MAX + 1.0);
e7b24047 JA	114	}
	115	}
	116
1bd5d213	117	static inline uint32_t rand32_upto(struct frand_state *state, uint32_t end)
e0a04ac1	118	{
36dd3379 JA	119	uint32_t r;
	120
	121	assert(!state->use64);
e0a04ac1	122
36dd3379	123	r = __rand32(&state->state32);
cdfb5a85	124	end++;
1bd5d213	125	return (int) ((double)end * (r / (FRAND32_MAX + 1.0)));
e0a04ac1 JA	126	}
e0a04ac1 JA	127
1bd5d213	128	static inline uint64_t rand64_upto(struct frand_state *state, uint64_t end)
56c77c10 JA	129	{
	130	uint64_t r;
	131
1bd5d213 JA	132	assert(state->use64);
1bd5d213 JA	133
56c77c10	134	r = __rand64(&state->state64);
cdfb5a85	135	end++;
1bd5d213	136	return (uint64_t) ((double)end * (r / (FRAND64_MAX + 1.0)));
56c77c10 JA	137	}
56c77c10 JA	138
cdfb5a85 JA	139	/*
	140	* Generate a random value between 'start' and 'end', both inclusive
	141	*/
56c77c10 JA	142	static inline uint64_t rand_between(struct frand_state *state, uint64_t start,
	143	uint64_t end)
	144	{
	145	if (state->use64)
cdfb5a85	146	return start + rand64_upto(state, end - start);
56c77c10	147	else
cdfb5a85	148	return start + rand32_upto(state, end - start);
56c77c10 JA	149	}
56c77c10 JA	150
de4096e8 JA	151	extern void init_rand(struct frand_state *, bool);
de4096e8 JA	152	extern void init_rand_seed(struct frand_state *, unsigned int seed, bool);
7d9fb455	153	extern void __fill_random_buf(void *buf, unsigned int len, unsigned long seed);
3545a109	154	extern unsigned long fill_random_buf(struct frand_state , void buf, unsigned int len);
bc769898	155	extern void __fill_random_buf_percentage(unsigned long, void , unsigned int, unsigned int, unsigned int, char , unsigned int);
d1af2894	156	extern unsigned long fill_random_buf_percentage(struct frand_state , void , unsigned int, unsigned int, unsigned int, char *, unsigned int);
1fbbf72e JA	157
1fbbf72e JA	158	#endif