[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 FRAND32_MAX_PLUS_ONE	(1.0 * (1ULL << 32))
#define FRAND64_MAX	(-1ULL)
#define FRAND64_MAX_PLUS_ONE	(1.0 * (1ULL << 32) * (1ULL << 32))

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_PLUS_ONE;
	} else {
		uint32_t val = __rand32(&state->state32);

		return (val + 1.0) / FRAND32_MAX_PLUS_ONE;
	}
}

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_PLUS_ONE));
}

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_PLUS_ONE));
}

/*
 * 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);
}

static inline uint64_t __get_next_seed(struct frand_state *fs)
{
	uint64_t r = __rand(fs);

	if (sizeof(int) != sizeof(long *))
		r *= (unsigned long) __rand(fs);

	return r;
}

extern void init_rand(struct frand_state *, bool);
extern void init_rand_seed(struct frand_state *, uint64_t seed, bool);
extern void __fill_random_buf(void *buf, unsigned int len, uint64_t seed);
extern uint64_t fill_random_buf(struct frand_state *, void *buf, unsigned int len);
extern void __fill_random_buf_percentage(uint64_t, void *, unsigned int, unsigned int, unsigned int, char *, unsigned int);
extern uint64_t 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	8	#define FRAND32_MAX (-1U)
af3e7a8f	9	#define FRAND32_MAX_PLUS_ONE (1.0 * (1ULL << 32))
c3546b53	10	#define FRAND64_MAX (-1ULL)
af3e7a8f	11	#define FRAND64_MAX_PLUS_ONE (1.0 * (1ULL << 32) * (1ULL << 32))
2615cc4b	12
c3546b53	13	struct taus88_state {
1fbbf72e JA	14	unsigned int s1, s2, s3;
	15	};
	16
c3546b53 JA	17	struct taus258_state {
	18	uint64_t s1, s2, s3, s4, s5;
	19	};
	20
	21	struct frand_state {
	22	unsigned int use64;
	23	union {
	24	struct taus88_state state32;
	25	struct taus258_state state64;
	26	};
	27	};
	28
c3546b53 JA	29	static inline uint64_t rand_max(struct frand_state *state)
	30	{
	31	if (state->use64)
	32	return FRAND64_MAX;
	33	else
	34	return FRAND32_MAX;
	35	}
	36
	37	static inline void __frand32_copy(struct taus88_state *dst,
	38	struct taus88_state *src)
	39	{
	40	dst->s1 = src->s1;
	41	dst->s2 = src->s2;
	42	dst->s3 = src->s3;
	43	}
	44
	45	static inline void __frand64_copy(struct taus258_state *dst,
	46	struct taus258_state *src)
5c94b008 JA	47	{
	48	dst->s1 = src->s1;
	49	dst->s2 = src->s2;
	50	dst->s3 = src->s3;
c3546b53 JA	51	dst->s4 = src->s4;
c3546b53 JA	52	dst->s5 = src->s5;
5c94b008 JA	53	}
5c94b008 JA	54
c3546b53 JA	55	static inline void frand_copy(struct frand_state dst, struct frand_state src)
	56	{
	57	if (src->use64)
	58	__frand64_copy(&dst->state64, &src->state64);
	59	else
	60	__frand32_copy(&dst->state32, &src->state32);
	61
	62	dst->use64 = src->use64;
	63	}
	64
	65	static inline unsigned int __rand32(struct taus88_state *state)
1fbbf72e JA	66	{
	67	#define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b)
	68
	69	state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12);
	70	state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4);
	71	state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17);
	72
	73	return (state->s1 ^ state->s2 ^ state->s3);
	74	}
	75
c3546b53 JA	76	static inline uint64_t __rand64(struct taus258_state *state)
	77	{
	78	uint64_t xval;
	79
	80	xval = ((state->s1 << 1) ^ state->s1) >> 53;
	81	state->s1 = ((state->s1 & 18446744073709551614ULL) << 10) ^ xval;
	82
	83	xval = ((state->s2 << 24) ^ state->s2) >> 50;
	84	state->s2 = ((state->s2 & 18446744073709551104ULL) << 5) ^ xval;
	85
	86	xval = ((state->s3 << 3) ^ state->s3) >> 23;
	87	state->s3 = ((state->s3 & 18446744073709547520ULL) << 29) ^ xval;
	88
	89	xval = ((state->s4 << 5) ^ state->s4) >> 24;
	90	state->s4 = ((state->s4 & 18446744073709420544ULL) << 23) ^ xval;
	91
	92	xval = ((state->s5 << 3) ^ state->s5) >> 33;
	93	state->s5 = ((state->s5 & 18446744073701163008ULL) << 8) ^ xval;
	94
	95	return (state->s1 ^ state->s2 ^ state->s3 ^ state->s4 ^ state->s5);
	96	}
	97
	98	static inline uint64_t __rand(struct frand_state *state)
	99	{
	100	if (state->use64)
	101	return __rand64(&state->state64);
	102	else
	103	return __rand32(&state->state32);
	104	}
	105
e7b24047 JA	106	static inline double __rand_0_1(struct frand_state *state)
	107	{
	108	if (state->use64) {
	109	uint64_t val = __rand64(&state->state64);
	110
af3e7a8f	111	return (val + 1.0) / FRAND64_MAX_PLUS_ONE;
e7b24047 JA	112	} else {
	113	uint32_t val = __rand32(&state->state32);
	114
af3e7a8f	115	return (val + 1.0) / FRAND32_MAX_PLUS_ONE;
e7b24047 JA	116	}
	117	}
	118
1bd5d213	119	static inline uint32_t rand32_upto(struct frand_state *state, uint32_t end)
e0a04ac1	120	{
36dd3379 JA	121	uint32_t r;
	122
	123	assert(!state->use64);
e0a04ac1	124
36dd3379	125	r = __rand32(&state->state32);
cdfb5a85	126	end++;
af3e7a8f	127	return (int) ((double)end * (r / FRAND32_MAX_PLUS_ONE));
e0a04ac1 JA	128	}
e0a04ac1 JA	129
1bd5d213	130	static inline uint64_t rand64_upto(struct frand_state *state, uint64_t end)
56c77c10 JA	131	{
	132	uint64_t r;
	133
1bd5d213 JA	134	assert(state->use64);
1bd5d213 JA	135
56c77c10	136	r = __rand64(&state->state64);
cdfb5a85	137	end++;
af3e7a8f	138	return (uint64_t) ((double)end * (r / FRAND64_MAX_PLUS_ONE));
56c77c10 JA	139	}
56c77c10 JA	140
cdfb5a85 JA	141	/*
	142	* Generate a random value between 'start' and 'end', both inclusive
	143	*/
56c77c10 JA	144	static inline uint64_t rand_between(struct frand_state *state, uint64_t start,
	145	uint64_t end)
	146	{
	147	if (state->use64)
cdfb5a85	148	return start + rand64_upto(state, end - start);
56c77c10	149	else
cdfb5a85	150	return start + rand32_upto(state, end - start);
56c77c10 JA	151	}
56c77c10 JA	152
0d71aa98 BD	153	static inline uint64_t __get_next_seed(struct frand_state *fs)
	154	{
	155	uint64_t r = __rand(fs);
	156
	157	if (sizeof(int) != sizeof(long *))
	158	r *= (unsigned long) __rand(fs);
	159
	160	return r;
	161	}
	162
de4096e8	163	extern void init_rand(struct frand_state *, bool);
eda99d55	164	extern void init_rand_seed(struct frand_state *, uint64_t seed, bool);
9781c080 MHT	165	extern void __fill_random_buf(void *buf, unsigned int len, uint64_t seed);
	166	extern uint64_t fill_random_buf(struct frand_state , void buf, unsigned int len);
	167	extern void __fill_random_buf_percentage(uint64_t, void , unsigned int, unsigned int, unsigned int, char , unsigned int);
	168	extern uint64_t fill_random_buf_percentage(struct frand_state , void , unsigned int, unsigned int, unsigned int, char *, unsigned int);
1fbbf72e JA	169
1fbbf72e JA	170	#endif