#define INITIAL_THREAD_ID 0
+class Backtrack {
+public:
+ Backtrack(ModelAction *d, action_list_t *t) {
+ diverge = d;
+ actionTrace = t;
+ iter = actionTrace->begin();
+ }
+ ModelAction * get_diverge() { return diverge; }
+ action_list_t * get_trace() { return actionTrace; }
+ void advance_state() { iter++; }
+ ModelAction * get_state() {
+ return iter == actionTrace->end() ? NULL : *iter;
+ }
+private:
+ ModelAction *diverge;
+ action_list_t *actionTrace;
+ /* points to position in actionTrace as we replay */
+ action_list_t::iterator iter;
+};
+
ModelChecker *model;
+void free_action_list(action_list_t *list)
+{
+ action_list_t::iterator it;
+ for (it = list->begin(); it != list->end(); it++)
+ delete (*it);
+ delete list;
+}
+
ModelChecker::ModelChecker()
{
- /* First thread created will have id (INITIAL_THREAD_ID + 1) */
- this->used_thread_id = INITIAL_THREAD_ID;
+ /* First thread created will have id INITIAL_THREAD_ID */
+ this->next_thread_id = INITIAL_THREAD_ID;
+ used_sequence_numbers = 0;
/* Initialize default scheduler */
this->scheduler = new Scheduler();
this->exploring = NULL;
this->nextThread = THREAD_ID_T_NONE;
- rootNode = new TreeNode(NULL);
+ rootNode = new TreeNode();
currentNode = rootNode;
action_trace = new action_list_t();
}
ModelChecker::~ModelChecker()
{
- delete action_trace;
+ std::map<int, class Thread *, std::less< int >, MyAlloc< std::pair< int, class Thread * > > >::iterator it;
+ for (it = thread_map.begin(); it != thread_map.end(); it++)
+ delete (*it).second;
+ thread_map.clear();
+
+ free_action_list(action_trace);
+
delete this->scheduler;
delete rootNode;
}
void ModelChecker::reset_to_initial_state()
{
DEBUG("+++ Resetting to initial state +++\n");
- std::map<int, class Thread *>::iterator it;
+ std::map<int, class Thread *, std::less< int >, MyAlloc< std::pair< int, class Thread * > > >::iterator it;
for (it = thread_map.begin(); it != thread_map.end(); it++)
delete (*it).second;
thread_map.clear();
action_trace = new action_list_t();
currentNode = rootNode;
current_action = NULL;
- used_thread_id = INITIAL_THREAD_ID;
+ next_thread_id = INITIAL_THREAD_ID;
+ used_sequence_numbers = 0;
/* scheduler reset ? */
}
thread_id_t ModelChecker::get_next_id()
{
- return ++used_thread_id;
+ return next_thread_id++;
+}
+
+int ModelChecker::get_next_seq_num()
+{
+ return ++used_sequence_numbers;
}
Thread * ModelChecker::schedule_next_thread()
if (nextThread == THREAD_ID_T_NONE)
return NULL;
t = thread_map[id_to_int(nextThread)];
- if (t == NULL)
- DEBUG("*** error: thread not in thread_map: id = %d\n", nextThread);
+
+ ASSERT(t != NULL);
+
return t;
}
/* Else, we are trying to replay an execution */
exploring->advance_state();
- if (exploring->get_state() == NULL)
- DEBUG("*** error: reached end of backtrack trace\n");
+
+ ASSERT(exploring->get_state() != NULL);
return get_next_replay_thread();
}
bool ModelChecker::next_execution()
{
+ DBG();
+
num_executions++;
print_summary();
if ((exploring = model->get_next_backtrack()) == NULL)
return false;
+
+ if (DBG_ENABLED()) {
+ printf("Next execution will diverge at:\n");
+ exploring->get_diverge()->print();
+ print_list(exploring->get_trace());
+ }
+
model->reset_to_initial_state();
nextThread = get_next_replay_thread();
return true;
{
ModelAction *prev;
TreeNode *node;
+ Thread *t = get_thread(act->get_tid());
prev = get_last_conflict(act);
if (prev == NULL)
node = prev->get_node();
+ while (t && !node->is_enabled(t))
+ t = t->get_parent();
+
/* Check if this has been explored already */
- if (node->hasBeenExplored(act->get_tid()))
+ if (node->hasBeenExplored(t->get_id()))
return;
/* If this is a new backtracking point, mark the tree */
- if (node->setBacktrack(act->get_tid()) != 0)
+ if (node->setBacktrack(t->get_id()) != 0)
return;
DEBUG("Setting backtrack: conflict = %d, instead tid = %d\n",
- prev->get_tid(), act->get_tid());
+ prev->get_tid(), t->get_id());
if (DBG_ENABLED()) {
prev->print();
act->print();
nextThread = advance_backtracking_state();
next->set_node(currentNode);
set_backtracking(next);
- currentNode = currentNode->exploreChild(next->get_tid());
+ currentNode = currentNode->explore_child(next);
this->action_trace->push_back(next);
}
void ModelChecker::print_summary(void)
{
- action_list_t::iterator it;
-
printf("\n");
- printf("---------------------------------------------------------------------\n");
printf("Number of executions: %d\n", num_executions);
- printf("Total nodes created: %d\n\n", TreeNode::getTotalNodes());
+ printf("Total nodes created: %d\n", TreeNode::getTotalNodes());
scheduler->print();
- printf("Trace:\n\n");
+ print_list(action_trace);
+ printf("\n");
+
+}
+
+void ModelChecker::print_list(action_list_t *list)
+{
+ action_list_t::iterator it;
+
+ printf("---------------------------------------------------------------------\n");
+ printf("Trace:\n");
- for (it = action_trace->begin(); it != action_trace->end(); it++) {
- DBG();
+ for (it = list->begin(); it != list->end(); it++) {
(*it)->print();
}
printf("---------------------------------------------------------------------\n");
old->set_state(THREAD_READY);
return Thread::swap(old, get_system_context());
}
-
-ModelAction::ModelAction(action_type_t type, memory_order order, void *loc, int value)
-{
- Thread *t = thread_current();
- ModelAction *act = this;
-
- act->type = type;
- act->order = order;
- act->location = loc;
- act->tid = t->get_id();
- act->value = value;
-}
-
-bool ModelAction::is_read()
-{
- return type == ATOMIC_READ;
-}
-
-bool ModelAction::is_write()
-{
- return type == ATOMIC_WRITE;
-}
-
-bool ModelAction::is_acquire()
-{
- switch (order) {
- case memory_order_acquire:
- case memory_order_acq_rel:
- case memory_order_seq_cst:
- return true;
- default:
- return false;
- }
-}
-
-bool ModelAction::is_release()
-{
- switch (order) {
- case memory_order_release:
- case memory_order_acq_rel:
- case memory_order_seq_cst:
- return true;
- default:
- return false;
- }
-}
-
-bool ModelAction::same_var(ModelAction *act)
-{
- return location == act->location;
-}
-
-bool ModelAction::same_thread(ModelAction *act)
-{
- return tid == act->tid;
-}
-
-bool ModelAction::is_dependent(ModelAction *act)
-{
- if (!is_read() && !is_write())
- return false;
- if (!act->is_read() && !act->is_write())
- return false;
- if (same_var(act) && !same_thread(act) &&
- (is_write() || act->is_write()))
- return true;
- return false;
-}
-
-void ModelAction::print(void)
-{
- const char *type_str;
- switch (this->type) {
- case THREAD_CREATE:
- type_str = "thread create";
- break;
- case THREAD_YIELD:
- type_str = "thread yield";
- break;
- case THREAD_JOIN:
- type_str = "thread join";
- break;
- case ATOMIC_READ:
- type_str = "atomic read";
- break;
- case ATOMIC_WRITE:
- type_str = "atomic write";
- break;
- default:
- type_str = "unknown type";
- }
-
- printf("Thread: %d\tAction: %s\tMO: %d\tLoc: %#014zx\tValue: %d\n", id_to_int(tid), type_str, order, (size_t)location, value);
-}