schedule.cc

   1 /* -*- Mode: C; indent-tabs-mode: t -*- */
   2
   3 #include "threads.h"
   4 #include "schedule.h"
   5 #include "common.h"
   6 #include "model.h"
   7
   8 Scheduler::Scheduler():
   9 current(NULL)
  10 {
  11 }
  12
  13 void Scheduler::add_thread(Thread *t)
  14 {
  15         DEBUG("thread %d\n", t->get_id());
  16         readyList.push_back(t);
  17 }
  18
  19 void Scheduler::remove_thread(Thread *t)
  20 {
  21         if (current == t)
  22                 current = NULL;
  23         else
  24                 readyList.remove(t);
  25 }
  26
  27 Thread * Scheduler::next_thread(void)
  28 {
  29         Thread *t = model->schedule_next_thread();
  30
  31         if (t != NULL) {
  32                 current = t;
  33                 readyList.remove(t);
  34         } else if (readyList.empty()) {
  35                 t = NULL;
  36         } else {
  37                 t = readyList.front();
  38                 current = t;
  39                 readyList.pop_front();
  40         }
  41
  42         print();
  43
  44         return t;
  45 }
  46
  47 Thread * Scheduler::get_current_thread(void)
  48 {
  49         return current;
  50 }
  51
  52 void Scheduler::print()
  53 {
  54         if (current)
  55                 DEBUG("Current thread: %d\n", current->get_id());
  56         else
  57                 DEBUG("No current thread\n");
  58         DEBUG("Num. threads in ready list: %zu\n", readyList.size());
  59
  60         std::list<Thread *, MyAlloc< Thread * > >::iterator it;
  61         for (it = readyList.begin(); it != readyList.end(); it++)
  62                 DEBUG("In ready list: thread %d\n", (*it)->get_id());
  63 }