gprofng/testsuite/lib/smalltest.c

   1 #include <stdio.h>
   2 #include <time.h>
   3
   4 typedef long long hrtime_t;
   5
   6 hrtime_t
   7 gethrtime (void)
   8 {
   9   struct timespec tp;
  10   hrtime_t rc = 0;
  11 #ifdef CLOCK_MONOTONIC_RAW
  12   int r = clock_gettime (CLOCK_MONOTONIC_RAW, &tp);
  13 #else
  14   int r = clock_gettime (CLOCK_MONOTONIC, &tp);
  15 #endif
  16
  17   if (r == 0)
  18     rc = ((hrtime_t) tp.tv_sec) * 1e9 + (hrtime_t) tp.tv_nsec;
  19   return rc;
  20 }
  21
  22 volatile long x; /* temp variable for long calculation */
  23
  24 int
  25 main (int argc, char **argv)
  26 {
  27   long long count = 0;
  28   hrtime_t start = gethrtime ();
  29
  30   do
  31     {
  32       x = 0;
  33       for (int j = 0; j < 1000000; j++)
  34         x = x + 1;
  35       count++;
  36     }
  37   while (start + 2e9 > gethrtime ());
  38   printf("count=%lld  x=%lld\n", count, x);
  39   return 0;
  40 }
  41