model: add todo synchronization comment

[model-checker.git] / schedule.cc

diff --git a/schedule.cc b/schedule.cc
index a236bd0cc66644197e178e00d4cc44b0a195f3c2..dd35237b22232df0744e22baadaaceb54ae6affd 100644 (file)
--- a/schedule.cc
+++ b/schedule.cc
@@ -8,7 +8,7 @@
 
 /** Constructor */
 Scheduler::Scheduler() :
-       is_enabled(NULL),
+       enabled(NULL),
        enabled_len(0),
        curr_thread_index(0),
        current(NULL)
@@ -20,14 +20,25 @@ void Scheduler::set_enabled(Thread *t, enabled_type_t enabled_status) {
        if (threadid>=enabled_len) {
                enabled_type_t *new_enabled = (enabled_type_t *)snapshot_malloc(sizeof(enabled_type_t) * (threadid + 1));
                memset(&new_enabled[enabled_len], 0, (threadid+1-enabled_len)*sizeof(enabled_type_t));
-               if (is_enabled != NULL) {
-                       memcpy(new_enabled, is_enabled, enabled_len*sizeof(enabled_type_t));
-                       snapshot_free(is_enabled);
+               if (enabled != NULL) {
+                       memcpy(new_enabled, enabled, enabled_len*sizeof(enabled_type_t));
+                       snapshot_free(enabled);
                }
-               is_enabled=new_enabled;
+               enabled=new_enabled;
                enabled_len=threadid+1;
        }
-       is_enabled[threadid]=enabled_status;
+       enabled[threadid]=enabled_status;
+}
+
+/**
+ * @brief Check if a Thread is currently enabled
+ * @param t The Thread to check
+ * @return True if the Thread is currently enabled
+ */
+bool Scheduler::is_enabled(Thread *t) const
+{
+       int id = id_to_int(t->get_id());
+       return (id >= enabled_len) ? false : (enabled[id] == THREAD_ENABLED);
 }
 
 /**
@@ -37,6 +48,7 @@ void Scheduler::set_enabled(Thread *t, enabled_type_t enabled_status) {
 void Scheduler::add_thread(Thread *t)
 {
        DEBUG("thread %d\n", id_to_int(t->get_id()));
+       ASSERT(!t->is_model_thread());
        set_enabled(t, THREAD_ENABLED);
 }
 
@@ -68,6 +80,7 @@ void Scheduler::sleep(Thread *t)
  */
 void Scheduler::wake(Thread *t)
 {
+       ASSERT(!t->is_model_thread());
        set_enabled(t, THREAD_DISABLED);
        t->set_state(THREAD_READY);
 }
@@ -86,7 +99,7 @@ Thread * Scheduler::next_thread(Thread *t)
                int old_curr_thread = curr_thread_index;
                while(true) {
                        curr_thread_index = (curr_thread_index+1) % enabled_len;
-                       if (is_enabled[curr_thread_index]) {
+                       if (enabled[curr_thread_index]) {
                                t = model->get_thread(int_to_id(curr_thread_index));
                                break;
                        }
@@ -95,6 +108,9 @@ Thread * Scheduler::next_thread(Thread *t)
                                return NULL;
                        }
                }
+       } else if (t->is_model_thread()) {
+               /* model-checker threads never run */
+               t = NULL;
        } else {
                curr_thread_index = id_to_int(t->get_id());
        }
@@ -109,6 +125,7 @@ Thread * Scheduler::next_thread(Thread *t)
  */
 Thread * Scheduler::get_current_thread() const
 {
+       ASSERT(!current || !current->is_model_thread());
        return current;
 }