test/benchmarks/exec/taskswitch2.c

   1 /*
   2     Copyright © 1995-2014, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include <stdio.h>
   7 #include <sys/time.h>
   8
   9 #ifndef __AROS__
  10 /*
  11    This is a trick to make the timer.device's timeval struct not clash with the
  12    sys/time.h's one. I'm using gettymeofday 'cause I'm lazy and don't wanna
  13    bother with timer.device myself :)
  14
  15    On AROS this is handled automatically (go AROS!)
  16 */
  17 #    define timeval timeval_aos
  18 #endif
  19
  20 #include <exec/tasks.h>
  21 #include <proto/exec.h>
  22 #include <clib/alib_protos.h>
  23 #include <proto/dos.h>
  24
  25 #ifndef __AROS__
  26 /* The trick is over... */
  27 #    undef timeval
  28 #endif
  29
  30 #ifndef  __typedef_STACKIPTR
  31 /* Normal AmigaOS environments don't have this defined */
  32 typedef ULONG STACKIPTR;
  33 #endif
  34
  35 #ifndef AROS_STACKSIZE
  36 #    define AROS_STACKSIZE 4096
  37 #endif
  38
  39 /* Give some prettier names to the standard signals */
  40 #define SIGF_STOP  SIGBREAKF_CTRL_C
  41 #define SIGF_HELLO SIGBREAKF_CTRL_D
  42 #define SIGF_BYE   SIGBREAKF_CTRL_E
  43 #define SIGF_START SIGBREAKF_CTRL_F
  44
  45 static unsigned long counter = 0;
  46 static struct Task *task1, *task2;
  47
  48 static struct timeval start_tv, end_tv;
  49
  50 void Task1Entry()
  51 {
  52     for (;;)
  53     {
  54         if (Wait(SIGF_HELLO | SIGF_STOP) == SIGF_HELLO)
  55             Signal(task2, SIGF_HELLO);
  56         else
  57         {
  58             Wait(SIGF_BYE);
  59             return;
  60         }
  61     }
  62 }
  63
  64 void Task2Entry()
  65 {
  66     Wait(SIGF_START);
  67
  68     for (;;)
  69     {
  70         Signal(task1, SIGF_HELLO);
  71         if (Wait(SIGF_HELLO | SIGF_STOP) == SIGF_HELLO)
  72             counter++;
  73         else
  74         {
  75             Signal(task1, SIGF_BYE);
  76             return;
  77         }
  78     }
  79 }
  80
  81 int __nocommandline = 1;
  82
  83 /*
  84    define this to non-zero if you want the benchmark to end automatically
  85    when it realizes that there's no need to continue.
  86
  87    Beware that it can introduce some overhead (although very little).
  88 */
  89 #define SELF_TIMED_TEST 0
  90
  91 int main(void)
  92 {
  93     double elapsed = 0;
  94
  95     task1 = CreateTask("Task 1", 0, Task1Entry, AROS_STACKSIZE);
  96     task2 = CreateTask("Task 2", 0, Task2Entry, AROS_STACKSIZE);
  97
  98     printf
  99     (
 100         "The test is starting.\n"
 101         #if !SELF_TIMED_TEST
 102         "Press CTRL-C to stop the test and get the results.\n"
 103         "Wait a few seconds before doing so, in order to get a more accurate result\n\n"
 104         #endif
 105     );
 106
 107     gettimeofday(&start_tv, NULL);
 108
 109     Signal(task2, SIGF_START);
 110
 111     #if SELF_TIMED_TEST
 112     {
 113         unsigned long i;
 114         double oldratio = 0;
 115
 116         for (i=4;;i+=2)
 117         {
 118             double ratio;
 119             Delay(200);
 120
 121             ratio = (double)i/counter;
 122             if ((ratio - oldratio) <= .000000001) break;
 123
 124             oldratio = ratio;
 125         }
 126     }
 127
 128     #else
 129
 130     Wait(SIGF_STOP);
 131
 132     #endif
 133
 134     gettimeofday(&end_tv, NULL);
 135
 136     Signal(task1, SIGF_STOP);
 137     Signal(task2, SIGF_STOP);
 138
 139     elapsed =  ((double)(((end_tv.tv_sec * 1000000) + end_tv.tv_usec) - ((start_tv.tv_sec * 1000000) + start_tv.tv_usec)))/1000000.;
 140
 141     printf
 142     (
 143         "Elapsed time:               %f seconds\n"
 144         "Number of context switches: %ld\n"
 145         "Signal roundtrip time:      %.8f\n"
 146         "Context switch time:     <= %.8f seconds\n",
 147         elapsed,
 148         counter * 2,
 149         elapsed / (double)counter,
 150         elapsed / (double)(counter * 2)
 151     );
 152
 153     return 0;
 154 }