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 #include "../gettime.h" 12 #include "../fio_time.h" 13 14 void usage() 15 { 16 printf("Usage: lfsr-test 0x<numbers> [seed] [spin] [verify]\n"); 17 printf("-------------------------------------------------------------\n"); 18 printf("*numbers: how many random numbers to produce (in hex)\n" 19 "seed: initial value\n" 20 "spin: how many iterations before we produce a number\n" 21 "verify: check if LFSR has iterated correctly\n\n" 22 "Only <numbers> is required. The rest are evaluated to 0 or false\n" 23 "Elapsed/mean time and verification results are printed at the" 24 "end of the test\n"); 25 } 26 27 int main(int argc, char *argv[]) 28 { 29 int r; 30 struct timeval start, end; 31 struct fio_lfsr *fl; 32 int verify = 0; 33 unsigned int spin = 0; 34 uint64_t seed = 0; 35 uint64_t numbers; 36 uint64_t v_size; 37 uint64_t i; 38 void *v = NULL, *v_start; 39 double total, mean; 40 41 arch_init(argv); 42 43 /* Read arguments */ 44 switch (argc) { 45 case 5: if (strncmp(argv[4], "verify", 7) == 0) 46 verify = 1; 47 case 4: spin = atoi(argv[3]); 48 case 3: seed = atol(argv[2]); 49 case 2: numbers = strtol(argv[1], NULL, 16); 50 break; 51 default: usage(); 52 return 1; 53 } 54 55 /* Initialize LFSR */ 56 fl = malloc(sizeof(struct fio_lfsr)); 57 if (!fl) { 58 perror("malloc"); 59 return 1; 60 } 61 62 r = lfsr_init(fl, numbers, seed, spin); 63 if (r) { 64 printf("Initialization failed.\n"); 65 return r; 66 } 67 68 /* Print specs */ 69 printf("LFSR specs\n"); 70 printf("==========================\n"); 71 printf("Size is %u\n", 64 - __builtin_clzl(fl->cached_bit)); 72 printf("Max val is %lu\n", (unsigned long) fl->max_val); 73 printf("XOR-mask is 0x%lX\n", (unsigned long) fl->xormask); 74 printf("Seed is %lu\n", (unsigned long) fl->last_val); 75 printf("Spin is %u\n", fl->spin); 76 printf("Cycle length is %lu\n", (unsigned long) fl->cycle_length); 77 78 /* Create verification table */ 79 if (verify) { 80 v_size = numbers * sizeof(uint8_t); 81 v = malloc(v_size); 82 memset(v, 0, v_size); 83 printf("\nVerification table is %lf KiB\n", (double)(v_size) / 1024); 84 } 85 v_start = v; 86 87 /* 88 * Iterate over a tight loop until we have produced all the requested 89 * numbers. Verifying the results should introduce some small yet not 90 * negligible overhead. 91 */ 92 fprintf(stderr, "\nTest initiated... "); 93 fio_gettime(&start, NULL); 94 while (!lfsr_next(fl, &i)) { 95 if (verify) 96 *(uint8_t *)(v + i) += 1; 97 } 98 fio_gettime(&end, NULL); 99 fprintf(stderr, "finished.\n"); 100 101 102 /* Check if all expected numbers within range have been calculated */ 103 r = 0; 104 if (verify) { 105 fprintf(stderr, "Verifying results... "); 106 for (i = 0; i < numbers; i++) { 107 if (*(uint8_t *)(v + i) != 1) { 108 fprintf(stderr, "failed (%lu = %d).\n", 109 (unsigned long) i, 110 *(uint8_t *)(v + i)); 111 r = 1; 112 break; 113 } 114 } 115 if (!r) 116 fprintf(stderr, "OK!\n"); 117 } 118 119 /* Calculate elapsed time and mean time per number */ 120 total = utime_since(&start, &end); 121 mean = total / fl->num_vals; 122 123 printf("\nTime results "); 124 if (verify) 125 printf("(slower due to verification)"); 126 printf("\n==============================\n"); 127 printf("Elapsed: %lf s\n", total / pow(10,6)); 128 printf("Mean: %lf us\n", mean); 129 130 free(v_start); 131 free(fl); 132 return r; 133 } 134
