natanael/ex06/ex06c.c

   1 /* ex06a.c */
   2
   3 #include <stdio.h>
   4 #include <signal.h>
   5 #include <unistd.h>
   6 #include <sys/mman.h>
   7
   8 #include <native/task.h>
   9 #include <native/timer.h>
  10 #include <native/sem.h>
  11
  12 #include  <rtdk.h>
  13 #include <sys/io.h>
  14
  15 #define NTASKS 3
  16
  17 #define HIGH 52 /* high priority */
  18 #define MID 51 /* medium priority */
  19 #define LOW 50  /* low priority */
  20
  21 RT_TASK demo_task[NTASKS];
  22 RT_SEM mysync;
  23
  24 #define BASEPERIOD 0   // baseperiod 0 to get ns
  25
  26 #define EXECTIME   2e8   // execution time in ns
  27 #define SPINTIME   1e7   // spin time in ns
  28
  29 void demo(void *arg)
  30 {
  31         RTIME starttime, runtime;
  32     int num=*(int *)arg;
  33     RT_TASK *curtask;
  34     RT_TASK_INFO curtaskinfo;
  35
  36         curtask=rt_task_self();
  37     rt_printf("Task  : %d\n",num);
  38
  39     rt_sem_p(&mysync,TM_INFINITE);
  40
  41     runtime = 0;
  42     while(runtime < EXECTIME) {
  43       rt_timer_spin(SPINTIME);  // spin cpu doing nothing
  44
  45       runtime = runtime + SPINTIME;
  46
  47       rt_printf("Running Task  : %d  at ms : %d\n",num,runtime/1000000);
  48           if(runtime == (EXECTIME/2)){
  49                   if(num == 2){
  50                           rt_task_set_priority(&demo_task[1],MID+10);
  51                           rt_task_set_priority(&demo_task[0],LOW+10);
  52                   }
  53           }
  54     }
  55     rt_printf("End Task  : %d\n",num);
  56 }
  57
  58 //startup code
  59 void startup()
  60 {
  61   int i;
  62   char  str[10] ;
  63
  64   // semaphore to sync task startup on
  65   rt_sem_create(&mysync,"MySemaphore",0,S_FIFO);
  66
  67   // set timing to ns
  68   rt_timer_set_mode(BASEPERIOD);
  69
  70   for(i=0; i < NTASKS; i++) {
  71     rt_printf("start task  : %d\n",i);
  72     sprintf(str,"task%d",i);
  73     rt_task_create(&demo_task[i], str, 0, 50, 0);
  74     rt_task_start(&demo_task[i], &demo, &i);
  75   }
  76   // assign priorities to tasks
  77   // (or in creation use 50+i)
  78   rt_task_set_priority(&demo_task[0],LOW);
  79   rt_task_set_priority(&demo_task[1],MID);
  80   rt_task_set_priority(&demo_task[2],HIGH);
  81
  82   rt_printf("wake up all tasks\n");
  83   rt_sem_broadcast(&mysync);
  84 }
  85
  86 void init_xenomai() {
  87   /* Avoids memory swapping for this program */
  88   mlockall(MCL_CURRENT|MCL_FUTURE);
  89
  90   /* Perform auto-init of rt_print buffers if the task doesn't do so */
  91   rt_print_auto_init(1);
  92 }
  93
  94 int main(int argc, char* argv[])
  95 {
  96   printf("\nType CTRL-C to end this program\n\n" );
  97
  98   // code to set things to run xenomai
  99   init_xenomai();
 100
 101   //startup code
 102   startup();
 103
 104   // wait for CTRL-c is typed to end the program
 105   pause();
 106 }