rand: add 64-bit tausworthe variant with a 2^258 cycle

[fio.git] / io_u.c

diff --git a/io_u.c b/io_u.c
index e67149d8cd2463e3bb8b06d18a70be9476b7b6d5..63a176f5eb02b315f3646bfca3fd299279e4f5e4 100644 (file)
--- a/io_u.c
+++ b/io_u.c
@@ -89,18 +89,20 @@ static int __get_next_rand_offset(struct thread_data *td, struct fio_file *f,
 {
        uint64_t r;
 
-       if (td->o.random_generator == FIO_RAND_GEN_TAUSWORTHE) {
-               uint64_t lastb;
+       if (td->o.random_generator == FIO_RAND_GEN_TAUSWORTHE ||
+           td->o.random_generator == FIO_RAND_GEN_TAUSWORTHE64) {
+               uint64_t frand_max, lastb;
 
                lastb = last_block(td, f, ddir);
                if (!lastb)
                        return 1;
 
+               frand_max = rand_max(&td->random_state);
                r = __rand(&td->random_state);
 
                dprint(FD_RANDOM, "off rand %llu\n", (unsigned long long) r);
 
-               *b = lastb * (r / ((uint64_t) FRAND_MAX + 1.0));
+               *b = lastb * (r / ((uint64_t) frand_max + 1.0));
        } else {
                uint64_t off = 0;
 
@@ -195,7 +197,8 @@ static inline int should_sort_io(struct thread_data *td)
                return 0;
        if (td->runstate != TD_VERIFYING)
                return 0;
-       if (td->o.random_generator == FIO_RAND_GEN_TAUSWORTHE)
+       if (td->o.random_generator == FIO_RAND_GEN_TAUSWORTHE ||
+           td->o.random_generator == FIO_RAND_GEN_TAUSWORTHE64)
                return 0;
 
        return 1;
@@ -203,14 +206,16 @@ static inline int should_sort_io(struct thread_data *td)
 
 static int should_do_random(struct thread_data *td, enum fio_ddir ddir)
 {
+       uint64_t frand_max;
        unsigned int v;
        unsigned long r;
 
        if (td->o.perc_rand[ddir] == 100)
                return 1;
 
+       frand_max = rand_max(&td->seq_rand_state[ddir]);
        r = __rand(&td->seq_rand_state[ddir]);
-       v = 1 + (int) (100.0 * (r / (FRAND_MAX + 1.0)));
+       v = 1 + (int) (100.0 * (r / (frand_max + 1.0)));
 
        return v <= td->o.perc_rand[ddir];
 }
@@ -439,6 +444,7 @@ static unsigned int __get_next_buflen(struct thread_data *td, struct io_u *io_u,
        int ddir = io_u->ddir;
        unsigned int buflen = 0;
        unsigned int minbs, maxbs;
+       uint64_t frand_max;
        unsigned long r;
 
        assert(ddir_rw(ddir));
@@ -458,12 +464,13 @@ static unsigned int __get_next_buflen(struct thread_data *td, struct io_u *io_u,
        if (!io_u_fits(td, io_u, minbs))
                return 0;
 
+       frand_max = rand_max(&td->bsrange_state);
        do {
                r = __rand(&td->bsrange_state);
 
                if (!td->o.bssplit_nr[ddir]) {
                        buflen = 1 + (unsigned int) ((double) maxbs *
-                                       (r / (FRAND_MAX + 1.0)));
+                                       (r / (frand_max + 1.0)));
                        if (buflen < minbs)
                                buflen = minbs;
                } else {
@@ -475,7 +482,7 @@ static unsigned int __get_next_buflen(struct thread_data *td, struct io_u *io_u,
 
                                buflen = bsp->bs;
                                perc += bsp->perc;
-                               if ((r <= ((FRAND_MAX / 100L) * perc)) &&
+                               if ((r <= ((frand_max / 100L) * perc)) &&
                                    io_u_fits(td, io_u, buflen))
                                        break;
                        }
@@ -521,11 +528,12 @@ static void set_rwmix_bytes(struct thread_data *td)
 
 static inline enum fio_ddir get_rand_ddir(struct thread_data *td)
 {
+       uint64_t frand_max = rand_max(&td->rwmix_state);
        unsigned int v;
        unsigned long r;
 
        r = __rand(&td->rwmix_state);
-       v = 1 + (int) (100.0 * (r / (FRAND_MAX + 1.0)));
+       v = 1 + (int) (100.0 * (r / (frand_max + 1.0)));
 
        if (v <= td->o.rwmix[DDIR_READ])
                return DDIR_READ;
@@ -992,6 +1000,7 @@ static struct fio_file *get_next_file_rand(struct thread_data *td,
                                           enum fio_file_flags goodf,
                                           enum fio_file_flags badf)
 {
+       uint64_t frand_max = rand_max(&td->next_file_state);
        struct fio_file *f;
        int fno;
 
@@ -1001,7 +1010,7 @@ static struct fio_file *get_next_file_rand(struct thread_data *td,
 
                r = __rand(&td->next_file_state);
                fno = (unsigned int) ((double) td->o.nr_files
-                               * (r / (FRAND_MAX + 1.0)));
+                               * (r / (frand_max + 1.0)));
 
                f = td->files[fno];
                if (fio_file_done(f))
@@ -1892,6 +1901,7 @@ void io_u_queued(struct thread_data *td, struct io_u *io_u)
  */
 static struct frand_state *get_buf_state(struct thread_data *td)
 {
+       uint64_t frand_max;
        unsigned int v;
        unsigned long r;
 
@@ -1902,8 +1912,9 @@ static struct frand_state *get_buf_state(struct thread_data *td)
                return &td->buf_state;
        }
 
+       frand_max = rand_max(&td->dedupe_state);
        r = __rand(&td->dedupe_state);
-       v = 1 + (int) (100.0 * (r / (FRAND_MAX + 1.0)));
+       v = 1 + (int) (100.0 * (r / (frand_max + 1.0)));
 
        if (v <= td->o.dedupe_percentage)
                return &td->buf_state_prev;