#include <algorithm>
#include <new>
#include <stdarg.h>
+#include <string.h>
+#include <cstdlib>
#include "model.h"
#include "action.h"
#include "output.h"
#include "traceanalysis.h"
#include "execution.h"
+#include "history.h"
#include "bugmessage.h"
+#include "params.h"
-ModelChecker *model;
+ModelChecker *model = NULL;
+
+/** Wrapper to run the user's main function, with appropriate arguments */
+void user_main_wrapper(void *)
+{
+ user_main(model->params.argc, model->params.argv);
+}
/** @brief Constructor */
-ModelChecker::ModelChecker(struct model_params params) :
+ModelChecker::ModelChecker() :
/* Initialize default scheduler */
- params(params),
+ params(),
+ restart_flag(false),
scheduler(new Scheduler()),
node_stack(new NodeStack()),
- execution(new ModelExecution(this, &this->params, scheduler, node_stack)),
+ execution(new ModelExecution(this, scheduler, node_stack)),
+ history(new ModelHistory()),
execution_number(1),
- diverge(NULL),
- earliest_diverge(NULL),
- trace_analyses()
+ trace_analyses(),
+ inspect_plugin(NULL)
{
+ memset(&stats,0,sizeof(struct execution_stats));
+ init_thread = new Thread(execution->get_next_id(), (thrd_t *) model_malloc(sizeof(thrd_t)), &user_main_wrapper, NULL, NULL); // L: user_main_wrapper passes the user program
+ execution->add_thread(init_thread);
+ scheduler->set_current_thread(init_thread);
+ execution->setParams(¶ms);
+ param_defaults(¶ms);
}
/** @brief Destructor */
ModelChecker::~ModelChecker()
{
delete node_stack;
- for (unsigned int i = 0; i < trace_analyses.size(); i++)
- delete trace_analyses[i];
delete scheduler;
}
+/** Method to set parameters */
+model_params * ModelChecker::getParams() {
+ return ¶ms;
+}
+
/**
* Restores user program to initial state and resets all model-checker data
* structures.
*/
void ModelChecker::reset_to_initial_state()
{
- DEBUG("+++ Resetting to initial state +++\n");
- node_stack->reset_execution();
/**
* FIXME: if we utilize partial rollback, we will need to free only
* those pending actions which were NOT pending before the rollback
* point
*/
- for (unsigned int i = 0; i < get_num_threads(); i++)
+ for (unsigned int i = 0;i < get_num_threads();i++)
delete get_thread(int_to_id(i))->get_pending();
snapshot_backtrack_before(0);
*/
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());
}
/**
/** @brief Print bug report listing for this execution (if any bugs exist) */
void ModelChecker::print_bugs() const
{
- if (execution->have_bug_reports()) {
- SnapVector<bug_message *> *bugs = execution->get_bugs();
-
- model_print("Bug report: %zu bug%s detected\n",
- bugs->size(),
- bugs->size() > 1 ? "s" : "");
- for (unsigned int i = 0; i < bugs->size(); i++)
- (*bugs)[i]->print();
- }
+ SnapVector<bug_message *> *bugs = execution->get_bugs();
+
+ model_print("Bug report: %zu bug%s detected\n",
+ bugs->size(),
+ bugs->size() > 1 ? "s" : "");
+ for (unsigned int i = 0;i < bugs->size();i++)
+ (*bugs)[i] -> print();
}
/**
*/
void ModelChecker::record_stats()
{
- stats.num_total++;
+ stats.num_total ++;
if (!execution->isfeasibleprefix())
- stats.num_infeasible++;
+ stats.num_infeasible ++;
else if (execution->have_bug_reports())
- stats.num_buggy_executions++;
+ stats.num_buggy_executions ++;
else if (execution->is_complete_execution())
- stats.num_complete++;
+ stats.num_complete ++;
else {
- stats.num_redundant++;
+ stats.num_redundant ++;
/**
* @todo We can violate this ASSERT() when fairness/sleep sets
model_print("Number of buggy executions: %d\n", stats.num_buggy_executions);
model_print("Number of infeasible executions: %d\n", stats.num_infeasible);
model_print("Total executions: %d\n", stats.num_total);
- model_print("Total nodes created: %d\n", node_stack->get_total_nodes());
}
/**
*/
void ModelChecker::print_execution(bool printbugs) const
{
+ model_print("Program output from execution %d:\n",
+ get_execution_number());
print_program_output();
- if (params.verbose) {
- model_print("Earliest divergence point since last feasible execution:\n");
- if (earliest_diverge)
- earliest_diverge->print();
- else
- model_print("(Not set)\n");
-
- model_print("\n");
+ if (params.verbose >= 3) {
print_stats();
}
/* Don't print invalid bugs */
- if (printbugs)
+ if (printbugs && execution->have_bug_reports()) {
+ model_print("\n");
print_bugs();
+ }
model_print("\n");
execution->print_summary();
DBG();
/* Is this execution a feasible execution that's worth bug-checking? */
bool complete = execution->isfeasibleprefix() &&
- (execution->is_complete_execution() ||
- execution->have_bug_reports());
+ (execution->is_complete_execution() ||
+ execution->have_bug_reports());
/* End-of-execution bug checks */
if (complete) {
}
record_stats();
-
/* Output */
- if (params.verbose || (complete && execution->have_bug_reports()))
+ if ( (complete && params.verbose) || params.verbose>1 || (complete && execution->have_bug_reports()))
print_execution(complete);
else
clear_program_output();
- if (complete)
- earliest_diverge = NULL;
-
- if ((diverge = execution->get_next_backtrack()) == NULL)
- return false;
-
- if (DBG_ENABLED()) {
- model_print("Next execution will diverge at:\n");
- diverge->print();
+ if (restart_flag) {
+ do_restart();
+ return true;
}
-
- execution_number++;
-
+// test code
+ execution_number ++;
reset_to_initial_state();
- return true;
+ return false;
}
/** @brief Run trace analyses on complete trace */
void ModelChecker::run_trace_analyses() {
- for (unsigned int i = 0; i < trace_analyses.size(); i++)
- trace_analyses[i]->analyze(execution->get_action_trace());
+ for (unsigned int i = 0;i < trace_analyses.size();i ++)
+ trace_analyses[i] -> analyze(execution->get_action_trace());
}
/**
return execution->get_thread(act);
}
-/**
- * @brief Check if a Thread is currently enabled
- * @param t The Thread to check
- * @return True if the Thread is currently enabled
- */
-bool ModelChecker::is_enabled(Thread *t) const
-{
- return scheduler->is_enabled(t);
-}
-
-/**
- * @brief Check if a Thread is currently enabled
- * @param tid The ID of the Thread to check
- * @return True if the Thread is currently enabled
- */
-bool ModelChecker::is_enabled(thread_id_t tid) const
-{
- return scheduler->is_enabled(tid);
-}
-
/**
* Switch from a model-checker context to a user-thread context. This is the
* complement of ModelChecker::switch_to_master and must be called from the
Thread *old = thread_current();
scheduler->set_current_thread(NULL);
ASSERT(!old->get_pending());
+
+ if (inspect_plugin != NULL) {
+ inspect_plugin->inspectModelAction(act);
+ }
+
old->set_pending(act);
if (Thread::swap(old, &system_context) < 0) {
perror("swap threads");
return old->get_return_value();
}
-/** Wrapper to run the user's main function, with appropriate arguments */
-void user_main_wrapper(void *)
-{
- user_main(model->params.argc, model->params.argv);
+static void runChecker() {
+ model->run();
+ delete model;
+}
+
+void ModelChecker::startChecker() {
+ startExecution(get_system_context(), runChecker);
}
bool ModelChecker::should_terminate_execution()
execution->set_assert();
return true;
}
+ return false;
+}
- if (execution->too_many_steps())
- return 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;
+ reset_to_initial_state();
+ memset(&stats,0,sizeof(struct execution_stats));
+ execution_number = 1;
+}
+
+void ModelChecker::startMainThread() {
+ init_thread->set_state(THREAD_RUNNING);
+ scheduler->set_current_thread(init_thread);
+ thread_startup();
+}
+
+static bool is_nonsc_write(const ModelAction *act) {
+ if (act->get_type() == ATOMIC_WRITE) {
+ std::memory_order order = act->get_mo();
+ switch(order) {
+ case std::memory_order_relaxed:
+ case std::memory_order_release:
+ return true;
+ default:
+ return false;
+ }
+ }
return false;
}
/** @brief Run ModelChecker for the user program */
void ModelChecker::run()
{
- do {
- thrd_t user_thread;
- Thread *t = new Thread(execution->get_next_id(), &user_thread, &user_main_wrapper, NULL, NULL);
- execution->add_thread(t);
+ //Need to initial random number generator state to avoid resets on rollback
+ char random_state[256];
+ initstate(423121, random_state, sizeof(random_state));
+
+ for(int exec = 0;exec < params.maxexecutions;exec++) {
+ Thread * t = init_thread;
do {
/*
* 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++) {
+ ModelAction * pending;
+ 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_model_thread() && !thr->is_complete() && ((!(pending=thr->get_pending())) || is_nonsc_write(pending)) ) {
+ 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);
}
}
/* Don't schedule threads which should be disabled */
- for (unsigned int i = 0; i < get_num_threads(); i++) {
+ 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 && is_enabled(th) && !execution->check_action_enabled(act)) {
+ 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) */
+ * between-ModelAction bugs (e.g., data races) */
+
if (execution->has_asserted())
break;
-
if (!t)
t = get_next_thread();
if (!t || t->is_model_thread())
t->set_pending(NULL);
t = execution->take_step(curr);
} while (!should_terminate_execution());
-
- } while (next_execution());
-
- execution->fixup_release_sequences();
+ next_execution();
+ //restore random number generator state after rollback
+ setstate(random_state);
+ }
model_print("******* Model-checking complete: *******\n");
print_stats();
+
+ /* Have the trace analyses dump their output. */
+ for (unsigned int i = 0;i < trace_analyses.size();i++)
+ trace_analyses[i]->finish();
}