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-2); j++) printf(".");
  28     printf("Please keep the test running several minutes per GB of memory.\n");
  29     printf("Also check http://www.memtest86.com/ and http://pyropus.ca/software/memtester/");
  30     printf("\x1b[H\x1b[2K");          /* Cursor home, clear current line.  */
  31     printf("%s [%d]\n", title, pass); /* Print title. */
  32     progress_printed = 0;
  33     progress_full = ws.ws_col*(ws.ws_row-3);
  34     fflush(stdout);
  35 }
  36
  37 void memtest_progress_end(void) {
  38     printf("\x1b[H\x1b[2J");    /* Cursor home, clear screen. */
  39 }
  40
  41 void memtest_progress_step(size_t curr, size_t size, char c) {
  42     size_t chars = (curr*progress_full)/size, j;
  43
  44     for (j = 0; j < chars-progress_printed; j++) {
  45         printf("%c",c);
  46         progress_printed++;
  47     }
  48     fflush(stdout);
  49 }
  50
  51 /* Fill words stepping a single page at every write, so we continue to
  52  * touch all the pages in the smallest amount of time reducing the
  53  * effectiveness of caches, and making it hard for the OS to transfer
  54  * pages on the swap. */
  55 void memtest_fill(unsigned long *l, size_t bytes) {
  56     unsigned long step = 4096/sizeof(unsigned long);
  57     unsigned long words = bytes/sizeof(unsigned long)/2;
  58     unsigned long iwords = words/step;  /* words per iteration */
  59     unsigned long off, w, *l1, *l2;
  60
  61     assert((bytes & 4095) == 0);
  62     for (off = 0; off < step; off++) {
  63         l1 = l+off;
  64         l2 = l1+words;
  65         for (w = 0; w < iwords; w++) {
  66 #ifdef MEMTEST_32BIT
  67             *l1 = *l2 = ((unsigned long)     (rand()&0xffff)) |
  68                         (((unsigned long)    (rand()&0xffff)) << 16);
  69 #else
  70             *l1 = *l2 = ((unsigned long)     (rand()&0xffff)) |
  71                         (((unsigned long)    (rand()&0xffff)) << 16) |
  72                         (((unsigned long)    (rand()&0xffff)) << 32) |
  73                         (((unsigned long)    (rand()&0xffff)) << 48);
  74 #endif
  75             l1 += step;
  76             l2 += step;
  77             if ((w & 0xffff) == 0)
  78                 memtest_progress_step(w+iwords*off,words,'+');
  79         }
  80     }
  81 }
  82
  83 void memtest_compare(unsigned long *l, size_t bytes) {
  84     unsigned long words = bytes/sizeof(unsigned long)/2;
  85     unsigned long w, *l1, *l2;
  86
  87     assert((bytes & 4095) == 0);
  88     l1 = l;
  89     l2 = l1+words;
  90     for (w = 0; w < words; w++) {
  91         if (*l1 != *l2) {
  92             printf("\n*** MEMORY ERROR DETECTED: %p != %p (%lu vs %lu)\n",
  93                 (void*)l1, (void*)l2, *l1, *l2);
  94             exit(1);
  95         }
  96         l1 ++;
  97         l2 ++;
  98         if ((w & 0xffff) == 0) memtest_progress_step(w,words,'=');
  99     }
 100 }
 101
 102 void memtest_test(size_t megabytes, int passes) {
 103     size_t bytes = megabytes*1024*1024;
 104     unsigned long *m = malloc(bytes);
 105     int pass = 0, j;
 106
 107     if (m == NULL) {
 108         fprintf(stderr,"Unable to allocate %zu megabytes: %s",
 109             megabytes, strerror(errno));
 110         exit(1);
 111     }
 112     while (pass != passes) {
 113         pass++;
 114         memtest_progress_start("Random fill",pass);
 115         memtest_fill(m,bytes);
 116         memtest_progress_end();
 117         for (j = 0; j < 4; j++) {
 118             memtest_progress_start("Compare",pass);
 119             memtest_compare(m,bytes);
 120             memtest_progress_end();
 121         }
 122     }
 123 }
 124
 125 void memtest(size_t megabytes, int passes) {
 126     if (ioctl(1, TIOCGWINSZ, &ws) == -1) {
 127         ws.ws_col = 80;
 128         ws.ws_row = 20;
 129     }
 130     memtest_test(megabytes,passes);
 131     printf("\nYour memory passed this test.\n");
 132     printf("Please if you are still in doubt use the following two tools:\n");
 133     printf("1) memtest86: http://www.memtest86.com/\n");
 134     printf("2) memtester: http://pyropus.ca/software/memtester/\n");
 135     exit(0);
 136 }