src/memtest.c

   1 #include <stdlib.h>
   2 #include <stdio.h>
   3 #include <string.h>
   4 #include <assert.h>
   5 #include <limits.h>
   6 #include <errno.h>
   7 #include <termios.h>
   8 #include <sys/ioctl.h>
   9
  10 #if (ULONG_MAX == 4294967295UL)
  11 #define MEMTEST_32BIT
  12 #elif (ULONG_MAX == 18446744073709551615ULL)
  13 #define MEMTEST_64BIT
  14 #else
  15 #error "ULONG_MAX value not supported."
  16 #endif
  17
  18 static struct winsize ws;
  19 size_t progress_printed; /* Printed chars in screen-wide progress bar. */
  20 size_t progress_full; /* How many chars to write to fill the progress bar. */
  21
  22 void memtest_progress_start(char *title, int pass) {
  23     int j;
  24
  25     printf("\x1b[H\x1b[2J");    /* Cursor home, clear screen. */
  26     /* Fill with dots. */
  27     for (j = 0; j < ws.ws_col*ws.ws_row; j++) printf(".");
  28     printf("\x1b[H\x1b[2K");          /* Cursor home, clear current line.  */
  29     printf("%s [%d]\n", title, pass); /* Print title. */
  30     progress_printed = 0;
  31     progress_full = ws.ws_col*(ws.ws_row-1);
  32     fflush(stdout);
  33 }
  34
  35 void memtest_progress_end(void) {
  36     printf("\x1b[H\x1b[2J");    /* Cursor home, clear screen. */
  37 }
  38
  39 void memtest_progress_step(size_t curr, size_t size, char c) {
  40     size_t chars = (curr*progress_full)/size, j;
  41
  42     for (j = 0; j < chars-progress_printed; j++) {
  43         printf("%c",c);
  44         progress_printed++;
  45     }
  46     fflush(stdout);
  47 }
  48
  49 /* Fill words stepping a single page at every write, so we continue to
  50  * touch all the pages in the smallest amount of time reducing the
  51  * effectiveness of caches, and making it hard for the OS to transfer
  52  * pages on the swap. */
  53 void memtest_fill(unsigned long *l, size_t bytes) {
  54     unsigned long step = 4096/sizeof(unsigned long);
  55     unsigned long words = bytes/sizeof(unsigned long)/2;
  56     unsigned long iwords = words/step;  /* words per iteration */
  57     unsigned long off, w, *l1, *l2;
  58
  59     assert((bytes & 4095) == 0);
  60     for (off = 0; off < step; off++) {
  61         l1 = l+off;
  62         l2 = l1+words;
  63         for (w = 0; w < iwords; w++) {
  64 #ifdef MEMTEST_32BIT
  65             *l1 = *l2 = ((unsigned long)     (rand()&0xffff)) |
  66                         (((unsigned long)    (rand()&0xffff)) << 16);
  67 #else
  68             *l1 = *l2 = ((unsigned long)     (rand()&0xffff)) |
  69                         (((unsigned long)    (rand()&0xffff)) << 16) |
  70                         (((unsigned long)    (rand()&0xffff)) << 32) |
  71                         (((unsigned long)    (rand()&0xffff)) << 48);
  72 #endif
  73             l1 += step;
  74             l2 += step;
  75             if ((w & 0xffff) == 0)
  76                 memtest_progress_step(w+iwords*off,words,'+');
  77         }
  78     }
  79 }
  80
  81 void memtest_compare(unsigned long *l, size_t bytes) {
  82     unsigned long words = bytes/sizeof(unsigned long)/2;
  83     unsigned long w, *l1, *l2;
  84
  85     assert((bytes & 4095) == 0);
  86     l1 = l;
  87     l2 = l1+words;
  88     for (w = 0; w < words; w++) {
  89         if (*l1 != *l2) {
  90             printf("\n*** MEMORY ERROR DETECTED: %p != %p (%lu vs %lu)\n",
  91                 (void*)l1, (void*)l2, *l1, *l2);
  92             exit(1);
  93         }
  94         l1 ++;
  95         l2 ++;
  96         if ((w & 0xffff) == 0) memtest_progress_step(w,words,'=');
  97     }
  98 }
  99
 100 void memtest_test(size_t megabytes, int passes) {
 101     size_t bytes = megabytes*1024*1024;
 102     unsigned long *m = malloc(bytes);
 103     int pass = 0, j;
 104
 105     if (m == NULL) {
 106         fprintf(stderr,"Unable to allocate %zu megabytes: %s",
 107             megabytes, strerror(errno));
 108         exit(1);
 109     }
 110     while (pass != passes) {
 111         pass++;
 112         memtest_progress_start("Random fill",pass);
 113         memtest_fill(m,bytes);
 114         memtest_progress_end();
 115         for (j = 0; j < 4; j++) {
 116             memtest_progress_start("Compare",pass);
 117             memtest_compare(m,bytes);
 118             memtest_progress_end();
 119         }
 120     }
 121 }
 122
 123 void memtest(size_t megabytes, int passes) {
 124     if (ioctl(1, TIOCGWINSZ, &ws) == -1) {
 125         ws.ws_col = 80;
 126         ws.ws_row = 20;
 127     }
 128     memtest_test(megabytes,passes);
 129     printf("\nYour memory passed this test.\n");
 130     printf("Please if you are stil in doubt use the following two tools:\n");
 131     printf("1) memtest86: http://www.memtest86.com/\n");
 132     printf("2) memtester: http://pyropus.ca/software/memtester/\n");
 133     exit(0);
 134 }