Fix snapshot code

[model-checker.git] / schedule.cc

diff --git a/schedule.cc b/schedule.cc
index 915bbc90fb3daa8d5985decdf9e1641a93e59993..2ef4c4d2f968ef2c97dffbf8f17a3e80c447c9cd 100644 (file)
--- a/schedule.cc
+++ b/schedule.cc
@@ -6,13 +6,14 @@
 #include "common.h"
 #include "model.h"
 #include "nodestack.h"
+#include "execution.h"
 
 /**
  * Format an "enabled_type_t" for printing
  * @param e The type to format
  * @param str The output character array
  */
-static void enabled_type_to_string(enabled_type_t e, char *str)
+void enabled_type_to_string(enabled_type_t e, char *str)
 {
        const char *res;
        switch (e) {
@@ -35,6 +36,7 @@ static void enabled_type_to_string(enabled_type_t e, char *str)
 
 /** Constructor */
 Scheduler::Scheduler() :
+       execution(NULL),
        enabled(NULL),
        enabled_len(0),
        curr_thread_index(0),
@@ -42,6 +44,15 @@ Scheduler::Scheduler() :
 {
 }
 
+/**
+ * @brief Register the ModelExecution engine
+ * @param execution The ModelExecution which is controlling execution
+ */
+void Scheduler::register_engine(ModelExecution *execution)
+{
+       this->execution = execution;
+}
+
 void Scheduler::set_enabled(Thread *t, enabled_type_t enabled_status) {
        int threadid = id_to_int(t->get_id());
        if (threadid >= enabled_len) {
@@ -56,7 +67,7 @@ void Scheduler::set_enabled(Thread *t, enabled_type_t enabled_status) {
        }
        enabled[threadid] = enabled_status;
        if (enabled_status == THREAD_DISABLED)
-               model->check_promises_thread_disabled();
+               execution->check_promises_thread_disabled();
 }
 
 /**
@@ -96,6 +107,23 @@ bool Scheduler::is_sleep_set(const Thread *t) const
        return get_enabled(t) == THREAD_SLEEP_SET;
 }
 
+/**
+ * @brief Check if execution is stuck with no enabled threads and some sleeping
+ * thread
+ * @return True if no threads are enabled an some thread is in the sleep set;
+ * false otherwise
+ */
+bool Scheduler::all_threads_sleeping() const
+{
+       bool sleeping = false;
+       for (int i = 0; i < enabled_len; i++)
+               if (enabled[i] == THREAD_ENABLED)
+                       return false;
+               else if (enabled[i] == THREAD_SLEEP_SET)
+                       sleeping = true;
+       return sleeping;
+}
+
 enabled_type_t Scheduler::get_enabled(const Thread *t) const
 {
        int id = id_to_int(t->get_id());
@@ -177,55 +205,70 @@ void Scheduler::wake(Thread *t)
 }
 
 /**
- * Select a Thread. This implementation defaults to round-robin, if a
- * thread is not already provided.
+ * @brief Select a Thread to run via round-robin
+ *
+ * @param n The current Node, holding priority information for the next thread
+ * selection
  *
- * @param t Thread to run, if chosen by an external entity (e.g.,
- * ModelChecker). May be NULL to indicate no external choice.
  * @return The next Thread to run
  */
-Thread * Scheduler::next_thread(Thread *t)
+Thread * Scheduler::select_next_thread(Node *n)
 {
-       if (t == NULL) {
-               int old_curr_thread = curr_thread_index;
-               bool have_enabled_thread_with_priority = false;
-               Node *n = model->get_curr_node();
+       int old_curr_thread = curr_thread_index;
 
+       bool have_enabled_thread_with_priority = false;
+       if (model->params.fairwindow != 0) {
                for (int i = 0; i < enabled_len; i++) {
                        thread_id_t tid = int_to_id(i);
                        if (n->has_priority(tid)) {
                                DEBUG("Node (tid %d) has priority\n", i);
-                               //Have a thread with priority
                                if (enabled[i] != THREAD_DISABLED)
                                        have_enabled_thread_with_priority = true;
                        }
                }
+       }       
 
-               while (true) {
-                       curr_thread_index = (curr_thread_index + 1) % enabled_len;
-                       thread_id_t curr_tid = int_to_id(curr_thread_index);
-                       if (enabled[curr_thread_index] == THREAD_ENABLED &&
-                                       (!have_enabled_thread_with_priority || n->has_priority(curr_tid))) {
-                               t = model->get_thread(curr_tid);
-                               break;
-                       }
-                       if (curr_thread_index == old_curr_thread) {
-                               if (DBG_ENABLED())
-                                       print();
-                               return NULL;
+       for (int i = 0; i < enabled_len; i++) {
+               curr_thread_index = (old_curr_thread + i + 1) % enabled_len;
+               thread_id_t curr_tid = int_to_id(curr_thread_index);
+               if (model->params.yieldon) {
+                       bool bad_thread = false;
+                       for (int j = 0; j < enabled_len; j++) {
+                               thread_id_t tother = int_to_id(j);
+                               if ((enabled[j] != THREAD_DISABLED) && n->has_priority_over(curr_tid, tother)) {
+                                       bad_thread=true;
+                                       break;
+                               }
                        }
+                       if (bad_thread)
+                               continue;
+               }
+               
+               if (enabled[curr_thread_index] == THREAD_ENABLED &&
+                               (!have_enabled_thread_with_priority || n->has_priority(curr_tid))) {
+                       return model->get_thread(curr_tid);
                }
-       } else if (t->is_model_thread()) {
-               /* model-checker threads never run */
-               t = NULL;
-       } else {
-               curr_thread_index = id_to_int(t->get_id());
        }
+       
+       /* No thread was enabled */
+       return NULL;
+}
+
+void Scheduler::set_scheduler_thread(thread_id_t tid) {
+       curr_thread_index=id_to_int(tid);
+}
+
+/**
+ * @brief Set the current "running" Thread
+ * @param t Thread to run
+ */
+void Scheduler::set_current_thread(Thread *t)
+{
+       ASSERT(!t || !t->is_model_thread());
 
        current = t;
        if (DBG_ENABLED())
                print();
-       return t;
 }
 
 /**