#include <algorithm>
#include <new>
#include <stdarg.h>
+#include <string.h>
+#include <cstdlib>
#include "model.h"
#include "action.h"
ModelChecker::ModelChecker(struct model_params params) :
/* Initialize default scheduler */
params(params),
+ restart_flag(false),
+ exit_flag(false),
scheduler(new Scheduler()),
node_stack(new NodeStack()),
execution(new ModelExecution(this, &this->params, scheduler, node_stack)),
execution_number(1),
diverge(NULL),
earliest_diverge(NULL),
- trace_analyses()
+ trace_analyses(),
+ inspect_plugin(NULL)
{
+ memset(&stats,0,sizeof(struct execution_stats));
}
/** @brief Destructor */
*/
Thread * ModelChecker::get_next_thread()
{
- thread_id_t tid;
/*
* Have we completed exploring the preselected path? Then let the
* scheduler decide
*/
- if (diverge == NULL)
- return scheduler->select_next_thread(node_stack->get_head());
-
-
- /* Else, we are trying to replay an execution */
- ModelAction *next = node_stack->get_next()->get_action();
-
- if (next == diverge) {
- if (earliest_diverge == NULL || *diverge < *earliest_diverge)
- earliest_diverge = diverge;
-
- Node *nextnode = next->get_node();
- Node *prevnode = nextnode->get_parent();
- scheduler->update_sleep_set(prevnode);
-
- /* Reached divergence point */
- if (nextnode->increment_behaviors()) {
- /* Execute the same thread with a new behavior */
- tid = next->get_tid();
- node_stack->pop_restofstack(2);
- } else {
- ASSERT(prevnode);
- /* Make a different thread execute for next step */
- scheduler->add_sleep(get_thread(next->get_tid()));
- tid = prevnode->get_next_backtrack();
- /* Make sure the backtracked thread isn't sleeping. */
- node_stack->pop_restofstack(1);
- if (diverge == earliest_diverge) {
- earliest_diverge = prevnode->get_action();
- }
- }
- /* Start the round robin scheduler from this thread id */
- scheduler->set_scheduler_thread(tid);
- /* The correct sleep set is in the parent node. */
- execute_sleep_set();
-
- DEBUG("*** Divergence point ***\n");
-
- diverge = NULL;
- } else {
- tid = next->get_tid();
- }
- DEBUG("*** ModelChecker chose next thread = %d ***\n", id_to_int(tid));
- ASSERT(tid != THREAD_ID_T_NONE);
- return get_thread(id_to_int(tid));
-}
-
-/**
- * We need to know what the next actions of all threads in the sleep
- * set will be. This method computes them and stores the actions at
- * the corresponding thread object's pending action.
- */
-void ModelChecker::execute_sleep_set()
-{
- for (unsigned int i = 0; i < get_num_threads(); i++) {
- thread_id_t tid = int_to_id(i);
- Thread *thr = get_thread(tid);
- if (scheduler->is_sleep_set(thr) && thr->get_pending()) {
- thr->get_pending()->set_sleep_flag();
- }
- }
+ return scheduler->select_next_thread(node_stack->get_head());
}
/**
checkDataRaces();
run_trace_analyses();
- }
+ }
record_stats();
-
/* Output */
if ( (complete && params.verbose) || params.verbose>1 || (complete && execution->have_bug_reports()))
print_execution(complete);
else
clear_program_output();
+ if (restart_flag) {
+ do_restart();
+ return true;
+ }
+// test code
+ execution_number++;
+ reset_to_initial_state();
+ node_stack->full_reset();
+ diverge = NULL;
+ return false;
+/* test
if (complete)
earliest_diverge = NULL;
- if ((diverge = execution->get_next_backtrack()) == NULL)
+ if (exit_flag)
+ return false;
+
+// diverge = execution->get_next_backtrack();
+ if (diverge == NULL) {
+ execution_number++;
+ reset_to_initial_state();
+ model_print("Does not diverge\n");
return false;
+ }
if (DBG_ENABLED()) {
model_print("Next execution will diverge at:\n");
reset_to_initial_state();
return true;
+*/
+
}
/** @brief Run trace analyses on complete trace */
Thread *old = thread_current();
scheduler->set_current_thread(NULL);
ASSERT(!old->get_pending());
+/* W: No plugin
+ if (inspect_plugin != NULL) {
+ inspect_plugin->inspectModelAction(act);
+ }*/
old->set_pending(act);
if (Thread::swap(old, &system_context) < 0) {
perror("swap threads");
return false;
}
+/** @brief Exit ModelChecker upon returning to the run loop of the
+ * model checker. */
+void ModelChecker::exit_model_checker()
+{
+ exit_flag = true;
+}
+
+/** @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;
+ diverge = NULL;
+ earliest_diverge = NULL;
+ reset_to_initial_state();
+ node_stack->full_reset();
+ memset(&stats,0,sizeof(struct execution_stats));
+ execution_number = 1;
+}
+
/** @brief Run ModelChecker for the user program */
void ModelChecker::run()
{
+ int i = 0;
+ //Need to initial random number generator state to avoid resets on rollback
+ char random_state[256];
+ initstate(423121, random_state, sizeof(random_state));
do {
thrd_t user_thread;
- Thread *t = new Thread(execution->get_next_id(), &user_thread, &user_main_wrapper, NULL, NULL);
+ Thread *t = new Thread(execution->get_next_id(), &user_thread, &user_main_wrapper, NULL, NULL); // L: user_main_wrapper passes the user program
execution->add_thread(t);
-
+ //Need to seed random number generator, otherwise its state gets reset
do {
/*
* Stash next pending action(s) for thread(s). There
* 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);
+ switch_from_master(thr); // L: context swapped, and action type of thr changed.
if (thr->is_waiting_on(thr))
assert_bug("Deadlock detected (thread %u)", i);
}
}
}
+ 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)
+ if (!t)
t = get_next_thread();
if (!t || t->is_model_thread())
break;
t->set_pending(NULL);
t = execution->take_step(curr);
} while (!should_terminate_execution());
-
- } while (next_execution());
-
- execution->fixup_release_sequences();
+ next_execution();
+ i++;
+ //restore random number generator state after rollback
+ setstate(random_state);
+ } while (i<5); // while (has_next);
model_print("******* Model-checking complete: *******\n");
print_stats();