| 1 | #include <stdio.h> |
| 2 | #include <stdlib.h> |
| 3 | #include <time.h> |
| 4 | #include <math.h> |
| 5 | #include <string.h> |
| 6 | #include <unistd.h> |
| 7 | #include <sys/types.h> |
| 8 | #include <sys/stat.h> |
| 9 | |
| 10 | #include "../lib/lfsr.h" |
| 11 | |
| 12 | void usage() |
| 13 | { |
| 14 | printf("Usage: lfsr-test 0x<numbers> [seed] [spin] [verify]\n"); |
| 15 | printf("-------------------------------------------------------------\n"); |
| 16 | printf("*numbers: how many random numbers to produce (in hex)\n" |
| 17 | "seed: initial value\n" |
| 18 | "spin: how many iterations before we produce a number\n" |
| 19 | "verify: check if LFSR has iterated correctly\n\n" |
| 20 | "Only <numbers> is required. The rest are evaluated to 0 or false\n" |
| 21 | "Elapsed/mean time and verification results are printed at the" |
| 22 | "end of the test\n"); |
| 23 | } |
| 24 | |
| 25 | int main(int argc, char *argv[]) |
| 26 | { |
| 27 | int r; |
| 28 | struct timespec start, end; |
| 29 | struct fio_lfsr *fl; |
| 30 | int verify = 0; |
| 31 | unsigned int spin = 0; |
| 32 | uint64_t seed = 0; |
| 33 | uint64_t numbers; |
| 34 | uint64_t v_size; |
| 35 | uint64_t i; |
| 36 | void *v = NULL, *v_start; |
| 37 | double total, mean; |
| 38 | |
| 39 | /* Read arguments */ |
| 40 | switch (argc) { |
| 41 | case 5: if (strncmp(argv[4], "verify", 7) == 0) |
| 42 | verify = 1; |
| 43 | case 4: spin = atoi(argv[3]); |
| 44 | case 3: seed = atol(argv[2]); |
| 45 | case 2: numbers = strtol(argv[1], NULL, 16); |
| 46 | break; |
| 47 | default: usage(); |
| 48 | return 1; |
| 49 | } |
| 50 | |
| 51 | /* Initialize LFSR */ |
| 52 | fl = malloc(sizeof(struct fio_lfsr)); |
| 53 | if (!fl) { |
| 54 | perror("malloc"); |
| 55 | return 1; |
| 56 | } |
| 57 | |
| 58 | r = lfsr_init(fl, numbers, seed, spin); |
| 59 | if (r) { |
| 60 | printf("Initialization failed.\n"); |
| 61 | return r; |
| 62 | } |
| 63 | |
| 64 | /* Print specs */ |
| 65 | printf("LFSR specs\n"); |
| 66 | printf("==========================\n"); |
| 67 | printf("Size is %u\n", 64 - __builtin_clzl(fl->cached_bit)); |
| 68 | printf("Max val is %lu\n", fl->max_val); |
| 69 | printf("XOR-mask is 0x%lX\n", fl->xormask); |
| 70 | printf("Seed is %lu\n", fl->last_val); |
| 71 | printf("Spin is %u\n", fl->spin); |
| 72 | printf("Cycle length is %lu\n", fl->cycle_length); |
| 73 | |
| 74 | /* Create verification table */ |
| 75 | if (verify) { |
| 76 | v_size = numbers * sizeof(uint8_t); |
| 77 | v = malloc(v_size); |
| 78 | memset(v, 0, v_size); |
| 79 | printf("\nVerification table is %lf KBs\n", (double)(v_size) / 1024); |
| 80 | } |
| 81 | v_start = v; |
| 82 | |
| 83 | /* |
| 84 | * Iterate over a tight loop until we have produced all the requested |
| 85 | * numbers. Verifying the results should introduce some small yet not |
| 86 | * negligible overhead. |
| 87 | */ |
| 88 | fprintf(stderr, "\nTest initiated... "); |
| 89 | clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &start); |
| 90 | while (!lfsr_next(fl, &i, fl->max_val)) { |
| 91 | if (verify) |
| 92 | *(uint8_t *)(v + i) += 1; |
| 93 | } |
| 94 | clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &end); |
| 95 | fprintf(stderr, "finished.\n"); |
| 96 | |
| 97 | |
| 98 | /* Check if all expected numbers within range have been calculated */ |
| 99 | r = 0; |
| 100 | if (verify) { |
| 101 | fprintf(stderr, "Verifying results... "); |
| 102 | for (i = 0; i < numbers; i++) { |
| 103 | if (*(uint8_t *)(v + i) != 1) { |
| 104 | fprintf(stderr, "failed (%lu = %d).\n", |
| 105 | i, *(uint8_t *)(v + i)); |
| 106 | r = 1; |
| 107 | break; |
| 108 | } |
| 109 | } |
| 110 | if (!r) |
| 111 | fprintf(stderr, "OK!\n"); |
| 112 | } |
| 113 | |
| 114 | /* Calculate elapsed time and mean time per number */ |
| 115 | total = (end.tv_sec - start.tv_sec) * pow(10,9) + |
| 116 | end.tv_nsec - start.tv_nsec; |
| 117 | mean = total / fl->num_vals; |
| 118 | |
| 119 | printf("\nTime results "); |
| 120 | if (verify) |
| 121 | printf("(slower due to verification)"); |
| 122 | printf("\n==============================\n"); |
| 123 | printf("Elapsed: %lf s\n", total / pow(10,9)); |
| 124 | printf("Mean: %lf ns\n", mean); |
| 125 | |
| 126 | free(v_start); |
| 127 | free(fl); |
| 128 | return r; |
| 129 | } |