#include <stdio.h>
#include "model.h"
+#include "action.h"
+#include "tree.h"
#include "schedule.h"
+#include "snapshot-interface.h"
+#undef DEBUG
+#include "common.h"
+
+#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 (system_thread) will have id 1 */
- this->used_thread_id = 0;
+ /* 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 DefaultScheduler();
+ this->scheduler = new Scheduler();
+
+ num_executions = 0;
+ this->current_action = NULL;
+ this->exploring = NULL;
+ this->nextThread = THREAD_ID_T_NONE;
+
+ rootNode = new TreeNode();
+ currentNode = rootNode;
+ action_trace = new action_list_t();
}
ModelChecker::~ModelChecker()
{
+ 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 *, 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;
+ next_thread_id = INITIAL_THREAD_ID;
+ used_sequence_numbers = 0;
+ /* scheduler reset ? */
+}
+
+thread_id_t ModelChecker::get_next_id()
+{
+ return next_thread_id++;
+}
+
+int ModelChecker::get_next_seq_num()
+{
+ return ++used_sequence_numbers;
+}
+
+Thread * ModelChecker::schedule_next_thread()
+{
+ Thread *t;
+ if (nextThread == THREAD_ID_T_NONE)
+ return NULL;
+ t = thread_map[id_to_int(nextThread)];
+
+ ASSERT(t != NULL);
+
+ return t;
+}
+
+/*
+ * get_next_replay_thread() - Choose the next thread in the replay sequence
+ *
+ * If we've reached the 'diverge' point, then we pick a thread from the
+ * backtracking set.
+ * Otherwise, we simply return the next thread in the sequence.
+ */
+thread_id_t ModelChecker::get_next_replay_thread()
+{
+ ModelAction *next;
+ thread_id_t tid;
+
+ next = exploring->get_state();
+
+ if (next == exploring->get_diverge()) {
+ TreeNode *node = next->get_node();
+
+ /* Reached divergence point; discard our current 'exploring' */
+ DEBUG("*** Discard 'Backtrack' object ***\n");
+ tid = node->getNextBacktrack();
+ delete exploring;
+ exploring = NULL;
+ } else {
+ tid = next->get_tid();
+ }
+ DEBUG("*** ModelChecker chose next thread = %d ***\n", tid);
+ return tid;
+}
+
+thread_id_t ModelChecker::advance_backtracking_state()
+{
+ /* Have we completed exploring the preselected path? */
+ if (exploring == NULL)
+ return THREAD_ID_T_NONE;
+
+ /* Else, we are trying to replay an execution */
+ exploring->advance_state();
+
+ ASSERT(exploring->get_state() != NULL);
+
+ return get_next_replay_thread();
}
-void ModelChecker::assign_id(struct thread *t)
+bool ModelChecker::next_execution()
{
- t->id = ++this->used_thread_id;
+ 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 * ModelChecker::get_last_conflict(ModelAction *act)
+{
+ action_type type = act->get_type();
+
+ switch (type) {
+ case THREAD_CREATE:
+ case THREAD_YIELD:
+ case THREAD_JOIN:
+ return NULL;
+ case ATOMIC_READ:
+ case ATOMIC_WRITE:
+ default:
+ break;
+ }
+ /* linear search: from most recent to oldest */
+ action_list_t::reverse_iterator rit;
+ for (rit = action_trace->rbegin(); rit != action_trace->rend(); rit++) {
+ ModelAction *prev = *rit;
+ if (act->is_dependent(prev))
+ return prev;
+ }
+ return NULL;
+}
+
+void ModelChecker::set_backtracking(ModelAction *act)
+{
+ ModelAction *prev;
+ TreeNode *node;
+ Thread *t = get_thread(act->get_tid());
+
+ prev = get_last_conflict(act);
+ if (prev == NULL)
+ return;
+
+ node = prev->get_node();
+
+ while (t && !node->is_enabled(t))
+ t = t->get_parent();
+
+ /* Check if this has been explored already */
+ if (node->hasBeenExplored(t->get_id()))
+ return;
+ /* If this is a new backtracking point, mark the tree */
+ if (node->setBacktrack(t->get_id()) != 0)
+ return;
+
+ DEBUG("Setting backtrack: conflict = %d, instead tid = %d\n",
+ prev->get_tid(), t->get_id());
+ if (DBG_ENABLED()) {
+ prev->print();
+ act->print();
+ }
+
+ Backtrack *back = new Backtrack(prev, action_trace);
+ backtrack_list.push_back(back);
}
-void ModelChecker::add_system_thread(struct thread *t)
+Backtrack * ModelChecker::get_next_backtrack()
{
- this->system_thread = t;
+ Backtrack *next;
+ if (backtrack_list.empty())
+ return NULL;
+ next = backtrack_list.back();
+ backtrack_list.pop_back();
+ return next;
+}
+
+void ModelChecker::check_current_action(void)
+{
+ ModelAction *next = this->current_action;
+
+ if (!next) {
+ DEBUG("trying to push NULL action...\n");
+ return;
+ }
+ current_action = NULL;
+ nextThread = advance_backtracking_state();
+ next->set_node(currentNode);
+ set_backtracking(next);
+ currentNode = currentNode->explore_child(next);
+ this->action_trace->push_back(next);
}
-ModelAction::ModelAction(action_type_t type, memory_order order, void *loc, int value)
+void ModelChecker::print_summary(void)
{
- struct thread *t = thread_current();
- ModelAction *act = this;
+ printf("\n");
+ printf("Number of executions: %d\n", num_executions);
+ printf("Total nodes created: %d\n", TreeNode::getTotalNodes());
+
+ scheduler->print();
+
+ print_list(action_trace);
+ printf("\n");
- act->type = type;
- act->order = order;
- act->location = loc;
- act->tid = t->id;
- act->value = value;
}
-void ModelAction::print(void)
+void ModelChecker::print_list(action_list_t *list)
{
- 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";
+ action_list_t::iterator it;
+
+ printf("---------------------------------------------------------------------\n");
+ printf("Trace:\n");
+
+ for (it = list->begin(); it != list->end(); it++) {
+ (*it)->print();
}
+ printf("---------------------------------------------------------------------\n");
+}
+
+int ModelChecker::add_thread(Thread *t)
+{
+ thread_map[id_to_int(t->get_id())] = t;
+ scheduler->add_thread(t);
+ return 0;
+}
+
+void ModelChecker::remove_thread(Thread *t)
+{
+ scheduler->remove_thread(t);
+}
+
+int ModelChecker::switch_to_master(ModelAction *act)
+{
+ Thread *old;
- printf("Thread: %d\tAction: %s\tMO: %d\tLoc: %#014zx\tValue: %d\n", tid, type_str, order, (size_t)location, value);
+ DBG();
+ old = thread_current();
+ set_current_action(act);
+ old->set_state(THREAD_READY);
+ return Thread::swap(old, get_system_context());
}
projects / c11tester.git / blobdiff