#include <algorithm>
#include <new>
#include <stdarg.h>
+#include <string.h>
+#include <cstdlib>
#include "model.h"
#include "action.h"
-#include "nodestack.h"
#include "schedule.h"
#include "snapshot-interface.h"
#include "common.h"
#include "output.h"
#include "traceanalysis.h"
#include "execution.h"
+#include "history.h"
#include "bugmessage.h"
+#include "params.h"
+#include "plugins.h"
-ModelChecker *model;
+ModelChecker *model = NULL;
+
+void placeholder(void *) {
+ ASSERT(0);
+}
/** @brief Constructor */
-ModelChecker::ModelChecker(struct model_params params) :
+ModelChecker::ModelChecker() :
/* Initialize default scheduler */
- params(params),
+ params(),
scheduler(new Scheduler()),
- node_stack(new NodeStack()),
- execution(new ModelExecution(this, &this->params, scheduler, node_stack)),
+ history(new ModelHistory()),
+ execution(new ModelExecution(this, scheduler)),
execution_number(1),
- diverge(NULL),
- earliest_diverge(NULL),
- trace_analyses()
+ trace_analyses(),
+ inspect_plugin(NULL)
{
+ model_print("C11Tester\n"
+ "Copyright (c) 2013 and 2019 Regents of the University of California. All rights reserved.\n"
+ "Distributed under the GPLv2\n"
+ "Written by Weiyu Luo, Brian Norris, and Brian Demsky\n\n");
+ memset(&stats,0,sizeof(struct execution_stats));
+ init_thread = new Thread(execution->get_next_id(), (thrd_t *) model_malloc(sizeof(thrd_t)), &placeholder, NULL, NULL);
+#ifdef TLS
+ init_thread->setTLS((char *)get_tls_addr());
+#endif
+ execution->add_thread(init_thread);
+ scheduler->set_current_thread(init_thread);
+ register_plugins();
+ execution->setParams(¶ms);
+ param_defaults(¶ms);
+ parse_options(¶ms);
+ initRaceDetector();
+ /* Configure output redirection for the model-checker */
+ redirect_output();
+ install_trace_analyses(get_execution());
}
/** @brief Destructor */
ModelChecker::~ModelChecker()
{
- delete node_stack;
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);
+ snapshot_roll_back(snapshot);
}
/** @return the number of user threads created during this execution */
*/
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();
}
/**
* @param msg Descriptive message for the bug (do not include newline char)
* @return True if bug is immediately-feasible
*/
-bool ModelChecker::assert_bug(const char *msg, ...)
+void ModelChecker::assert_bug(const char *msg, ...)
{
char str[800];
vsnprintf(str, sizeof(str), msg, ap);
va_end(ap);
- return execution->assert_bug(str);
+ execution->assert_bug(str);
}
/**
void ModelChecker::assert_user_bug(const char *msg)
{
/* If feasible bug, bail out now */
- if (assert_bug(msg))
- switch_to_master(NULL);
+ assert_bug(msg);
+ switch_to_master(NULL);
}
/** @brief Print bug report listing for this execution (if any bugs exist) */
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();
+ 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++;
- if (!execution->isfeasibleprefix())
- stats.num_infeasible++;
- else if (execution->have_bug_reports())
- stats.num_buggy_executions++;
+ stats.num_total ++;
+ if (execution->have_bug_reports())
+ stats.num_buggy_executions ++;
else if (execution->is_complete_execution())
- stats.num_complete++;
+ stats.num_complete ++;
else {
- stats.num_redundant++;
-
+ //All threads are sleeping
/**
* @todo We can violate this ASSERT() when fairness/sleep sets
* conflict to cause an execution to terminate, e.g. with:
void ModelChecker::print_stats() const
{
model_print("Number of complete, bug-free executions: %d\n", stats.num_complete);
- model_print("Number of redundant executions: %d\n", stats.num_redundant);
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);
- if (params.verbose)
- 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());
+ get_execution_number());
print_program_output();
- if (params.verbose >= 2) {
- model_print("\nEarliest 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();
}
* @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? */
- bool complete = execution->isfeasibleprefix() &&
- (execution->is_complete_execution() ||
- execution->have_bug_reports());
+ bool complete = (execution->is_complete_execution() ||
+ execution->have_bug_reports());
/* End-of-execution bug checks */
if (complete) {
if (execution->is_deadlocked())
assert_bug("Deadlock detected");
- checkDataRaces();
run_trace_analyses();
}
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();
- }
-
- execution_number++;
-
- reset_to_initial_state();
- return true;
+// test code
+ execution_number ++;
+ if (more_executions)
+ reset_to_initial_state();
+ history->set_new_exec_flag();
}
/** @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());
}
/**
*/
uint64_t ModelChecker::switch_to_master(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();
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 *)
+void ModelChecker::continueExecution(Thread *old)
{
- user_main(model->params.argc, model->params.argv);
+ 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 (Thread::swap(old, thr) < 0) {
+ perror("swap threads");
+ exit(EXIT_FAILURE);
+ }
+ } else
+ handleChosenThread(old);
}
-bool ModelChecker::should_terminate_execution()
+Thread* ModelChecker::getNextThread()
{
- /* Infeasible -> don't take any more steps */
- if (execution->is_infeasible())
- return true;
- else if (execution->isfeasibleprefix() && execution->have_bug_reports()) {
- execution->set_assert();
- return true;
+ Thread *thr = nullptr;
+ for (unsigned int i = curr_thread_num; i < get_num_threads(); i++) {
+ thread_id_t tid = int_to_id(i);
+ thr = get_thread(tid);
+
+ if (!thr->is_complete() && !thr->get_pending()) {
+ curr_thread_num = i;
+ break;
+ }
+ ModelAction *act = thr->get_pending();
+
+ if (act && execution->is_enabled(thr) && !execution->check_action_enabled(act)) {
+ scheduler->sleep(thr);
+ }
+
+ chooseThread(act, thr);
}
+ return thr;
+}
- if (execution->too_many_steps())
- return true;
- return false;
+void ModelChecker::finishExecution(Thread *old)
+{
+ scheduler->set_current_thread(NULL);
+ if (Thread::swap(old, &system_context) < 0) {
+ perror("swap threads");
+ exit(EXIT_FAILURE);
+ }
}
-/** @brief Run ModelChecker for the user program */
-void ModelChecker::run()
+void ModelChecker::consumeAction()
{
- do {
- thrd_t user_thread;
- Thread *t = new Thread(execution->get_next_id(), &user_thread, &user_main_wrapper, NULL, NULL);
- execution->add_thread(t);
-
- 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);
- }
- }
+ ModelAction *curr = chosen_thread->get_pending();
+ chosen_thread->set_pending(NULL);
+ chosen_thread = execution->take_step(curr);
+}
- /* 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);
- }
+void ModelChecker::chooseThread(ModelAction *act, Thread *old)
+{
+ if (!thread_chosen && act && execution->is_enabled(old) && (old->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 = old;
+ 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 = old;
+ 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());
- /* Catch assertions from prior take_step or from
- * between-ModelAction bugs (e.g., data races) */
- if (execution->has_asserted())
- break;
+ if (inspect_plugin != NULL) {
+ inspect_plugin->inspectModelAction(act);
+ }
+
+ old->set_pending(act);
+
+ curr_thread_num++;
+ Thread* next = getNextThread();
+ if (next != nullptr)
+ handleNewValidThread(old, next);
+ else
+ handleChosenThread(old);
+
+ return old->get_return_value();
+}
- if (!t)
- t = get_next_thread();
- if (!t || t->is_model_thread())
- break;
+void ModelChecker::handleNewValidThread(Thread *old, Thread *next)
+{
+ if (old->is_waiting_on(old))
+ assert_bug("Deadlock detected (thread %u)", curr_thread_num-1);
- /* Consume the next action for a Thread */
- ModelAction *curr = t->get_pending();
- t->set_pending(NULL);
- t = execution->take_step(curr);
- } while (!should_terminate_execution());
+ ModelAction *act = old->get_pending();
+
+ if (act && execution->is_enabled(old) && !execution->check_action_enabled(act)) {
+ scheduler->sleep(old);
+ }
+ chooseThread(act, old);
- } while (next_execution());
+ scheduler->set_current_thread(next);
- execution->fixup_release_sequences();
+ if (Thread::swap(old, next) < 0) {
+ perror("swap threads");
+ exit(EXIT_FAILURE);
+ }
+}
+
+void ModelChecker::handleChosenThread(Thread *old)
+{
+ if (execution->has_asserted())
+ finishExecution(old);
+ if (!chosen_thread)
+ chosen_thread = get_next_thread();
+ if (!chosen_thread || chosen_thread->is_model_thread())
+ finishExecution(old);
+ 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())
+ finishExecution(old);
+ else
+ continueExecution(old);
+ } else {
+ /* Consume the next action for a Thread */
+ consumeAction();
+
+ if (should_terminate_execution())
+ finishExecution(old);
+ else
+ continueExecution(old);
+ }
+}
+
+static void runChecker() {
+ model->run();
+ delete model;
+}
+
+void ModelChecker::startChecker() {
+ startExecution(get_system_context(), runChecker);
+ snapshot = take_snapshot();
+ initMainThread();
+}
+
+bool ModelChecker::should_terminate_execution()
+{
+ if (execution->have_bug_reports()) {
+ execution->set_assert();
+ return true;
+ } else if (execution->isFinished()) {
+ return true;
+ }
+ return false;
+}
+
+/** @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++) {
+ chosen_thread = init_thread;
+ thread_chosen = false;
+ curr_thread_num = 1;
+ thread_id_t tid = int_to_id(1);
+ Thread *thr = get_thread(tid);
+ switch_from_master(thr);
+ finish_execution((exec+1) < params.maxexecutions);
+ //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++)
+ for (unsigned int i = 0;i < trace_analyses.size();i++)
trace_analyses[i]->finish();
+
+ /* unlink tmp file created by last child process */
+ char filename[256];
+ snprintf_(filename, sizeof(filename), "C11FuzzerTmp%d", getpid());
+ unlink(filename);
}
projects / c11tester.git / blobdiff