test/benchmarks/exec/taskswitch2.c

   1 /* $Id$ */
   2
   3 #include <stdio.h>
   4 #include <sys/time.h>
   5
   6 #ifndef __AROS__
   7 /*
   8    This is a trick to make the timer.device's timeval struct not clash with the
   9    sys/time.h's one. I'm using gettymeofday 'cause I'm lazy and don't wanna
  10    bother with timer.device myself :)
  11
  12    On AROS this is handled automatically (go AROS!)
  13 */
  14 #    define timeval timeval_aos
  15 #endif
  16
  17 #include <exec/tasks.h>
  18 #include <proto/exec.h>
  19 #include <clib/alib_protos.h>
  20 #include <proto/dos.h>
  21
  22 #ifndef __AROS__
  23 /* The trick is over... */
  24 #    undef timeval
  25 #endif
  26
  27 #ifndef  __typedef_STACKIPTR
  28 /* Normal AmigaOS environments don't have this defined */
  29 typedef ULONG STACKIPTR;
  30 #endif
  31
  32 #ifndef AROS_STACKSIZE
  33 #    define AROS_STACKSIZE 4096
  34 #endif
  35
  36 /* Give some prettier names to the standard signals */
  37 #define SIGF_STOP  SIGBREAKF_CTRL_C
  38 #define SIGF_HELLO SIGBREAKF_CTRL_D
  39 #define SIGF_BYE   SIGBREAKF_CTRL_E
  40 #define SIGF_START SIGBREAKF_CTRL_F
  41
  42 static unsigned long counter = 0;
  43 static struct Task *task1, *task2;
  44
  45 static struct timeval start_tv, end_tv;
  46
  47 void Task1Entry()
  48 {
  49     for (;;)
  50     {
  51         if (Wait(SIGF_HELLO | SIGF_STOP) == SIGF_HELLO)
  52             Signal(task2, SIGF_HELLO);
  53         else
  54         {
  55             Wait(SIGF_BYE);
  56             return;
  57         }
  58     }
  59 }
  60
  61 void Task2Entry()
  62 {
  63     Wait(SIGF_START);
  64
  65     for (;;)
  66     {
  67         Signal(task1, SIGF_HELLO);
  68         if (Wait(SIGF_HELLO | SIGF_STOP) == SIGF_HELLO)
  69             counter++;
  70         else
  71         {
  72             Signal(task1, SIGF_BYE);
  73             return;
  74         }
  75     }
  76 }
  77
  78 int __nocommandline = 1;
  79
  80 /*
  81    define this to non-zero if you want the benchmark to end automatically
  82    when it realizes that there's no need to continue.
  83
  84    Beware that it can introduce some overhead (although very little).
  85 */
  86 #define SELF_TIMED_TEST 0
  87
  88 int main(void)
  89 {
  90     double elapsed = 0;
  91
  92     task1 = CreateTask("Task 1", 0, Task1Entry, AROS_STACKSIZE);
  93     task2 = CreateTask("Task 2", 0, Task2Entry, AROS_STACKSIZE);
  94
  95     printf
  96     (
  97         "The test is starting.\n"
  98         #if !SELF_TIMED_TEST
  99         "Press CTRL-C to stop the test and get the results.\n"
 100         "Wait a few seconds before doing so, in order to get a more accurate result\n\n"
 101         #endif
 102     );
 103
 104     gettimeofday(&start_tv, NULL);
 105
 106     Signal(task2, SIGF_START);
 107
 108     #if SELF_TIMED_TEST
 109     {
 110         unsigned long i;
 111         double oldratio = 0;
 112
 113         for (i=4;;i+=2)
 114         {
 115             double ratio;
 116             Delay(200);
 117
 118             ratio = (double)i/counter;
 119             if ((ratio - oldratio) <= .000000001) break;
 120
 121             oldratio = ratio;
 122         }
 123     }
 124
 125     #else
 126
 127     Wait(SIGF_STOP);
 128
 129     #endif
 130
 131     gettimeofday(&end_tv, NULL);
 132
 133     Signal(task1, SIGF_STOP);
 134     Signal(task2, SIGF_STOP);
 135
 136     elapsed =  ((double)(((end_tv.tv_sec * 1000000) + end_tv.tv_usec) - ((start_tv.tv_sec * 1000000) + start_tv.tv_usec)))/1000000.;
 137
 138     printf
 139     (
 140         "Elapsed time:               %f seconds\n"
 141         "Number of context switches: %ld\n"
 142         "Signal roundtrip time:      %.8f\n"
 143         "Context switch time:     <= %.8f seconds\n",
 144         elapsed,
 145         counter * 2,
 146         elapsed / (double)counter,
 147         elapsed / (double)(counter * 2)
 148     );
 149
 150     return 0;
 151 }