7 #include "snapshot-interface.h"
10 #define INITIAL_THREAD_ID 0
14 ModelChecker::ModelChecker()
16 /* Initialize default scheduler */
17 scheduler(new Scheduler()),
18 /* First thread created will have id INITIAL_THREAD_ID */
19 next_thread_id(INITIAL_THREAD_ID),
20 used_sequence_numbers(0),
25 nextThread(THREAD_ID_T_NONE),
26 action_trace(new action_list_t()),
27 thread_map(new std::map<int, class Thread *>),
28 node_stack(new NodeStack()),
33 ModelChecker::~ModelChecker()
35 std::map<int, class Thread *>::iterator it;
36 for (it = thread_map->begin(); it != thread_map->end(); it++)
46 void ModelChecker::reset_to_initial_state()
48 DEBUG("+++ Resetting to initial state +++\n");
49 node_stack->reset_execution();
50 current_action = NULL;
51 next_thread_id = INITIAL_THREAD_ID;
52 used_sequence_numbers = 0;
54 next_backtrack = NULL;
55 /* scheduler reset ? */
56 snapshotObject->backTrackBeforeStep(0);
59 thread_id_t ModelChecker::get_next_id()
61 return next_thread_id++;
64 int ModelChecker::get_next_seq_num()
66 return ++used_sequence_numbers;
69 Thread * ModelChecker::schedule_next_thread()
72 if (nextThread == THREAD_ID_T_NONE)
74 t = (*thread_map)[id_to_int(nextThread)];
82 * get_next_replay_thread() - Choose the next thread in the replay sequence
84 * If we've reached the 'diverge' point, then we pick a thread from the
86 * Otherwise, we simply return the next thread in the sequence.
88 thread_id_t ModelChecker::get_next_replay_thread()
93 /* Have we completed exploring the preselected path? */
95 return THREAD_ID_T_NONE;
97 /* Else, we are trying to replay an execution */
98 next = node_stack->get_next()->get_action();
100 if (next == diverge) {
101 Node *node = next->get_node();
103 /* Reached divergence point */
104 DEBUG("*** Divergence point ***\n");
105 tid = node->get_next_backtrack();
108 tid = next->get_tid();
110 DEBUG("*** ModelChecker chose next thread = %d ***\n", tid);
114 bool ModelChecker::next_execution()
120 if ((diverge = model->get_next_backtrack()) == NULL)
124 printf("Next execution will diverge at:\n");
128 model->reset_to_initial_state();
132 ModelAction * ModelChecker::get_last_conflict(ModelAction *act)
134 action_type type = act->get_type();
146 /* linear search: from most recent to oldest */
147 action_list_t::reverse_iterator rit;
148 for (rit = action_trace->rbegin(); rit != action_trace->rend(); rit++) {
149 ModelAction *prev = *rit;
150 if (act->is_dependent(prev))
156 void ModelChecker::set_backtracking(ModelAction *act)
160 Thread *t = get_thread(act->get_tid());
162 prev = get_last_conflict(act);
166 node = prev->get_node();
168 while (!node->is_enabled(t))
171 /* Check if this has been explored already */
172 if (node->has_been_explored(t->get_id()))
175 if (!next_backtrack || *prev > *next_backtrack)
176 next_backtrack = prev;
178 /* If this is a new backtracking point, mark the tree */
179 if (!node->set_backtrack(t->get_id()))
181 DEBUG("Setting backtrack: conflict = %d, instead tid = %d\n",
182 prev->get_tid(), t->get_id());
189 ModelAction * ModelChecker::get_next_backtrack()
191 ModelAction *next = next_backtrack;
192 next_backtrack = NULL;
196 void ModelChecker::check_current_action(void)
200 ModelAction *curr = this->current_action;
201 current_action = NULL;
203 DEBUG("trying to push NULL action...\n");
207 curr = node_stack->explore_action(curr);
208 nextThread = get_next_replay_thread();
210 currnode = curr->get_node();
212 if (!currnode->backtrack_empty())
213 if (!next_backtrack || *curr > *next_backtrack)
214 next_backtrack = curr;
216 set_backtracking(curr);
217 this->action_trace->push_back(curr);
220 void ModelChecker::print_summary(void)
223 printf("Number of executions: %d\n", num_executions);
224 printf("Total nodes created: %d\n", Node::get_total_nodes());
228 print_list(action_trace);
232 void ModelChecker::print_list(action_list_t *list)
234 action_list_t::iterator it;
236 printf("---------------------------------------------------------------------\n");
239 for (it = list->begin(); it != list->end(); it++) {
242 printf("---------------------------------------------------------------------\n");
245 int ModelChecker::add_thread(Thread *t)
247 (*thread_map)[id_to_int(t->get_id())] = t;
248 scheduler->add_thread(t);
252 void ModelChecker::remove_thread(Thread *t)
254 scheduler->remove_thread(t);
257 int ModelChecker::switch_to_master(ModelAction *act)
262 old = thread_current();
263 set_current_action(act);
264 old->set_state(THREAD_READY);
265 return Thread::swap(old, get_system_context());