X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=model.cc;h=090743a49ff0ce6da1a1627acdd1367ebdc5c0ac;hb=8899359d333648c680e9a1aecf34b45a1eb6a201;hp=a934d0adcb7be451907d3141243f4239564743d2;hpb=53601c28881fb6637665178ccefceafbd44cf019;p=c11tester.git

diff --git a/model.cc b/model.cc
index a934d0ad..090743a4 100644
--- a/model.cc
+++ b/model.cc
@@ -30,7 +30,6 @@ void placeholder(void *) {
 ModelChecker::ModelChecker() :
 	/* Initialize default scheduler */
 	params(),
-	restart_flag(false),
 	scheduler(new Scheduler()),
 	history(new ModelHistory()),
 	execution(new ModelExecution(this, scheduler)),
@@ -237,7 +236,7 @@ void ModelChecker::print_execution(bool printbugs) const
  * @return If there are more executions to explore, return true. Otherwise,
  * return false.
  */
-bool ModelChecker::next_execution()
+void ModelChecker::finish_execution(bool more_executions)
 {
 	DBG();
 	/* Is this execution a feasible execution that's worth bug-checking? */
@@ -259,15 +258,11 @@ bool ModelChecker::next_execution()
 	else
 		clear_program_output();
 
-	if (restart_flag) {
-		do_restart();
-		return true;
-	}
 // test code
 	execution_number ++;
-	reset_to_initial_state();
+	if (more_executions)
+		reset_to_initial_state();
 	history->set_new_exec_flag();
-	return false;
 }
 
 /** @brief Run trace analyses on complete trace */
@@ -349,6 +344,192 @@ uint64_t ModelChecker::switch_to_master(ModelAction *act)
 	return old->get_return_value();
 }
 
+void ModelChecker::startRunExecution(Thread *old) 
+{
+
+	if (params.traceminsize != 0 &&
+			execution->get_curr_seq_num() > checkfree) {
+		checkfree += params.checkthreshold;
+		execution->collectActions();
+	}
+
+	thread_chosen = false;
+	curr_thread_num = 1;
+	Thread *thr = getNextThread();
+	if (thr != nullptr) {
+		scheduler->set_current_thread(thr);
+		if (old) {
+			if (Thread::swap(old, thr) < 0) {
+				perror("swap threads");
+				exit(EXIT_FAILURE);
+			}
+		} else {
+			if (Thread::swap(&system_context, thr) < 0) {
+				perror("swap threads");
+				exit(EXIT_FAILURE);
+			}	
+		}
+	} else
+		handleChosenThread(old);
+}
+
+Thread* ModelChecker::getNextThread()
+{
+	Thread *nextThread = nullptr;
+	for (unsigned int i = curr_thread_num; i < get_num_threads(); i++) {
+		thread_id_t tid = int_to_id(i);
+		Thread *thr = get_thread(tid);
+		
+		if (!thr->is_complete() && !thr->get_pending()) {
+			curr_thread_num = i;
+			nextThread = thr;
+			break;
+		}
+		ModelAction *act = thr->get_pending();
+		
+		if (act && execution->is_enabled(thr) && !execution->check_action_enabled(act)) {
+			scheduler->sleep(thr);
+		}
+
+	chooseThread(act, thr);
+	}
+	return nextThread;
+}
+
+void ModelChecker::finishRunExecution(Thread *old) 
+{
+	scheduler->set_current_thread(NULL);
+	if (old != NULL) {
+		if (Thread::swap(old, &system_context) < 0) {
+			perror("swap threads");
+			exit(EXIT_FAILURE);
+		}
+	}
+	break_execution = true;
+}
+
+void ModelChecker::consumeAction()
+{
+	ModelAction *curr = chosen_thread->get_pending();
+	Thread * th = thread_current();
+	if (curr->get_type() == THREAD_FINISH && th != NULL)  {
+		// Thread finish must be consumed in the master context
+		scheduler->set_current_thread(NULL);
+		if (Thread::swap(th, &system_context) < 0) {
+			perror("swap threads");
+			exit(EXIT_FAILURE);
+		}
+	} else {
+		chosen_thread->set_pending(NULL);
+		chosen_thread = execution->take_step(curr);
+	}
+}
+
+void ModelChecker::chooseThread(ModelAction *act, Thread *thr)
+{
+	if (!thread_chosen && act && execution->is_enabled(thr) && (thr->get_state() != THREAD_BLOCKED) ) {
+		if (act->is_write()) {
+			std::memory_order order = act->get_mo();
+			if (order == std::memory_order_relaxed || \
+					order == std::memory_order_release) {
+				chosen_thread = thr;
+				thread_chosen = true;
+			}
+		} else if (act->get_type() == THREAD_CREATE || \
+							act->get_type() == PTHREAD_CREATE || \
+							act->get_type() == THREAD_START || \
+							act->get_type() == THREAD_FINISH) {
+			chosen_thread = thr;
+			thread_chosen = true;
+		}
+	}	
+}
+
+uint64_t ModelChecker::switch_thread(ModelAction *act)
+{
+	if (modellock) {
+		static bool fork_message_printed = false;
+
+		if (!fork_message_printed) {
+			model_print("Fork handler or dead thread trying to call into model checker...\n");
+			fork_message_printed = true;
+		}
+		delete act;
+		return 0;
+	}
+	DBG();
+	Thread *old = thread_current();
+	ASSERT(!old->get_pending());
+
+	if (inspect_plugin != NULL) {
+		inspect_plugin->inspectModelAction(act);
+	}
+
+	old->set_pending(act);
+	
+	if (old->is_waiting_on(old))
+		assert_bug("Deadlock detected (thread %u)", curr_thread_num);
+
+	if (act && execution->is_enabled(old) && !execution->check_action_enabled(act)) {
+		scheduler->sleep(old);
+	}
+	chooseThread(act, old);
+
+	curr_thread_num++;
+	Thread* next = getNextThread();
+	if (next != nullptr) 
+		handleNewValidThread(old, next);
+	else {
+		old->set_state(THREAD_READY);	// Just to avoid the first ASSERT in ModelExecution::take_step 
+		handleChosenThread(old);
+	}
+
+	return old->get_return_value();
+}
+
+void ModelChecker::handleNewValidThread(Thread *old, Thread *next)
+{
+	scheduler->set_current_thread(next);
+
+	if (Thread::swap(old, next) < 0) {
+		perror("swap threads");
+		exit(EXIT_FAILURE);
+	}
+}
+
+void ModelChecker::handleChosenThread(Thread *old)
+{
+	Thread * th = old ? old : thread_current();
+	if (execution->has_asserted()) {
+		finishRunExecution(th);
+		return;
+	}
+	if (!chosen_thread)
+		chosen_thread = get_next_thread();
+	if (!chosen_thread || chosen_thread->is_model_thread()) {
+		finishRunExecution(th);
+		return;
+	}
+	if (chosen_thread->just_woken_up()) {
+		chosen_thread->set_wakeup_state(false);
+		chosen_thread->set_pending(NULL);
+		chosen_thread = NULL;
+		// Allow this thread to stash the next pending action
+		if (should_terminate_execution())
+			finishRunExecution(th);
+		else
+			startRunExecution(th);
+	} else {
+		/* Consume the next action for a Thread */
+		consumeAction();
+
+		if (should_terminate_execution())
+			finishRunExecution(th);
+		else
+			startRunExecution(th);
+	}
+}
+
 static void runChecker() {
 	model->run();
 	delete model;
@@ -371,100 +552,26 @@ bool ModelChecker::should_terminate_execution()
 	return false;
 }
 
-/** @brief Restart ModelChecker upon returning to the run loop of the
- *	model checker. */
-void ModelChecker::restart()
-{
-	restart_flag = true;
-}
-
-void ModelChecker::do_restart()
-{
-	restart_flag = false;
-	reset_to_initial_state();
-	memset(&stats,0,sizeof(struct execution_stats));
-	execution_number = 1;
-}
-
 /** @brief Run ModelChecker for the user program */
 void ModelChecker::run()
 {
 	//Need to initial random number generator state to avoid resets on rollback
 	char random_state[256];
 	initstate(423121, random_state, sizeof(random_state));
-
+	checkfree = params.checkthreshold;
 	for(int exec = 0;exec < params.maxexecutions;exec++) {
-		Thread * t = init_thread;
-
+		chosen_thread = init_thread;
+		break_execution = false;
 		do {
-			/*
-			 * Stash next pending action(s) for thread(s). There
-			 * should only need to stash one thread's action--the
-			 * thread which just took a step--plus the first step
-			 * for any newly-created thread
-			 */
-			for (unsigned int i = 0;i < get_num_threads();i++) {
-				thread_id_t tid = int_to_id(i);
-				Thread *thr = get_thread(tid);
-				if (!thr->is_model_thread() && !thr->is_complete() && !thr->get_pending()) {
-					switch_from_master(thr);
-					if (thr->is_waiting_on(thr))
-						assert_bug("Deadlock detected (thread %u)", i);
-				}
-			}
-
-			/* Don't schedule threads which should be disabled */
-			for (unsigned int i = 0;i < get_num_threads();i++) {
-				Thread *th = get_thread(int_to_id(i));
-				ModelAction *act = th->get_pending();
-				if (act && execution->is_enabled(th) && !execution->check_action_enabled(act)) {
-					scheduler->sleep(th);
-				}
-			}
-
-			for (unsigned int i = 1;i < get_num_threads();i++) {
-				Thread *th = get_thread(int_to_id(i));
-				ModelAction *act = th->get_pending();
-				if (act && execution->is_enabled(th) && (th->get_state() != THREAD_BLOCKED) ) {
-					if (act->is_write()) {
-						std::memory_order order = act->get_mo();
-						if (order == std::memory_order_relaxed || \
-								order == std::memory_order_release) {
-							t = th;
-							break;
-						}
-					} else if (act->get_type() == THREAD_CREATE || \
-										 act->get_type() == PTHREAD_CREATE || \
-										 act->get_type() == THREAD_START || \
-										 act->get_type() == THREAD_FINISH) {
-						t = th;
-						break;
-					}
-				}
-			}
-
-			/* Catch assertions from prior take_step or from
-			* between-ModelAction bugs (e.g., data races) */
-
-			if (execution->has_asserted())
-				break;
-			if (!t)
-				t = get_next_thread();
-			if (!t || t->is_model_thread())
+			if (break_execution)
 				break;
-			if (t->just_woken_up()) {
-				t->set_wakeup_state(false);
-				t->set_pending(NULL);
-				t = NULL;
-				continue;	// Allow this thread to stash the next pending action
-			}
 
-			/* Consume the next action for a Thread */
-			ModelAction *curr = t->get_pending();
-			t->set_pending(NULL);
-			t = execution->take_step(curr);
+			thread_chosen = false;
+			curr_thread_num = 1;
+			startRunExecution(NULL);
 		} while (!should_terminate_execution());
-		next_execution();
+
+		finish_execution((exec+1) < params.maxexecutions);
 		//restore random number generator state after rollback
 		setstate(random_state);
 	}