test/sysperf/loop2.c

   1 /*
   2  * loop2.c
   3  *
   4  * Used as a helper to test AST delivery.  Loops in user mode for a few
   5  * seconds.  This one forks and runs the loop in two processes.
   6  *
   7  * $DragonFly: src/test/sysperf/loop2.c,v 1.2 2006/04/22 22:32:52 dillon Exp $
   8  */
   9
  10 #include "blib.h"
  11
  12 #define LOOP 1000000
  13 #define INNER 100
  14
  15 int
  16 main(int ac, char **av)
  17 {
  18     int i;
  19     int j;
  20     int count = LOOP;
  21     pid_t pid;
  22
  23     if (ac > 1)
  24         count = strtoul(av[1], NULL, 0);
  25
  26     printf("SMP contention, userland-only loop, duel-forks.  Run just one\n");
  27
  28     start_timing();
  29     if (fork() == 0) {
  30         for (i = count; i > 0; --i) {
  31             for (j = INNER; j > 0; --j)
  32                 nop();
  33         }
  34         _exit(1);
  35     } else {
  36         for (i = count; i > 0; --i) {
  37             for (j = INNER; j > 0; --j)
  38                 nop();
  39         }
  40         while (wait(NULL) > 0)
  41             ;
  42         stop_timing(LOOP, "loop2/2xfork");
  43     }
  44     return(0);
  45 }
  46