X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=model.cc;h=b5843ed6b7c5ebf6ba091e05afac6ac70593e1ae;hb=414b2df02223c9109c53228f905cea524a346cbf;hp=47c6cdb92d442f0b0f460e353e9d25c93cfb6dc7;hpb=d6def735e3fb70267ca802f3b1909e7ace6e4507;p=model-checker.git diff --git a/model.cc b/model.cc index 47c6cdb..b5843ed 100644 --- a/model.cc +++ b/model.cc @@ -25,6 +25,7 @@ ModelChecker::ModelChecker(struct model_params params) : num_executions(0), num_feasible_executions(0), diverge(NULL), + earliest_diverge(NULL), action_trace(new action_list_t()), thread_map(new HashTable()), obj_map(new HashTable()), @@ -98,6 +99,12 @@ int ModelChecker::get_num_threads() return priv->next_thread_id; } +/** @return The currently executing Thread. */ +Thread * ModelChecker::get_current_thread() +{ + return scheduler->get_current_thread(); +} + /** @return a sequence number for a new ModelAction */ modelclock_t ModelChecker::get_next_seq_num() { @@ -138,6 +145,9 @@ Thread * ModelChecker::get_next_thread(ModelAction *curr) 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(); /* Reached divergence point */ if (nextnode->increment_promise()) { @@ -157,8 +167,12 @@ Thread * ModelChecker::get_next_thread(ModelAction *curr) Node *node = nextnode->get_parent(); tid = node->get_next_backtrack(); node_stack->pop_restofstack(1); + if (diverge==earliest_diverge) { + earliest_diverge=node->get_action(); + } } DEBUG("*** Divergence point ***\n"); + diverge = NULL; } else { tid = next->get_tid(); @@ -180,8 +194,20 @@ bool ModelChecker::next_execution() DBG(); num_executions++; - if (isfinalfeasible()) + + if (isfinalfeasible()) { + printf("Earliest divergence point since last feasible execution:\n"); + if (earliest_diverge) + earliest_diverge->print(false); + else + printf("(Not set)\n"); + + earliest_diverge = NULL; num_feasible_executions++; + } + + DEBUG("Number of acquires waiting on pending release sequences: %lu\n", + pending_acq_rel_seq->size()); if (isfinalfeasible() || DBG_ENABLED()) print_summary(); @@ -414,7 +440,7 @@ bool ModelChecker::process_mutex(ModelAction *curr) { action_list_t *waiters = lock_waiters_map->get_safe_ptr(curr->get_location()); //activate all the waiting threads for (action_list_t::iterator rit = waiters->begin(); rit != waiters->end(); rit++) { - scheduler->add_thread(get_thread((*rit)->get_tid())); + scheduler->wake(get_thread(*rit)); } waiters->clear(); break; @@ -459,11 +485,11 @@ bool ModelChecker::process_write(ModelAction *curr) * (e.g., ATOMIC_{READ,WRITE,RMW,LOCK}, etc.) * * @param curr The current action - * @return True if synchronization was updated + * @return True if synchronization was updated or a thread completed */ bool ModelChecker::process_thread_action(ModelAction *curr) { - bool synchronized = false; + bool updated = false; switch (curr->get_type()) { case THREAD_CREATE: { @@ -480,7 +506,7 @@ bool ModelChecker::process_thread_action(ModelAction *curr) scheduler->sleep(waiting); } else { do_complete_join(curr); - synchronized = true; + updated = true; /* trigger rel-seq checks */ } break; } @@ -491,9 +517,10 @@ bool ModelChecker::process_thread_action(ModelAction *curr) Thread *wake = get_thread(act); scheduler->wake(wake); do_complete_join(act); - synchronized = true; + updated = true; /* trigger rel-seq checks */ } th->complete(); + updated = true; /* trigger rel-seq checks */ break; } case THREAD_START: { @@ -504,7 +531,7 @@ bool ModelChecker::process_thread_action(ModelAction *curr) break; } - return synchronized; + return updated; } /** @@ -525,10 +552,14 @@ ModelAction * ModelChecker::initialize_curr_action(ModelAction *curr) if (curr->is_rmwc() || curr->is_rmw()) { newcurr = process_rmw(curr); delete curr; - compute_promises(newcurr); + + if (newcurr->is_rmw()) + compute_promises(newcurr); return newcurr; } + curr->set_seq_number(get_next_seq_num()); + newcurr = node_stack->explore_action(curr, scheduler->get_enabled()); if (newcurr) { /* First restore type and order in case of RMW operation */ @@ -541,18 +572,19 @@ ModelAction * ModelChecker::initialize_curr_action(ModelAction *curr) /* Discard duplicate ModelAction; use action from NodeStack */ delete curr; - /* If we have diverged, we need to reset the clock vector. */ - if (diverge == NULL) - newcurr->create_cv(get_parent_action(newcurr->get_tid())); + /* Always compute new clock vector */ + newcurr->create_cv(get_parent_action(newcurr->get_tid())); } else { newcurr = curr; + + /* Always compute new clock vector */ + newcurr->create_cv(get_parent_action(newcurr->get_tid())); /* * Perform one-time actions when pushing new ModelAction onto * NodeStack */ - curr->create_cv(get_parent_action(curr->get_tid())); - if (curr->is_write()) - compute_promises(curr); + if (newcurr->is_write()) + compute_promises(newcurr); } return newcurr; } @@ -600,7 +632,7 @@ Thread * ModelChecker::check_current_action(ModelAction *curr) /* Make the execution look like we chose to run this action * much later, when a lock is actually available to release */ get_current_thread()->set_pending(curr); - remove_thread(get_current_thread()); + scheduler->sleep(get_current_thread()); return get_next_thread(NULL); } @@ -655,7 +687,8 @@ Thread * ModelChecker::check_current_action(ModelAction *curr) bool updated = false; if (act->is_read()) { - if (r_modification_order(act, act->get_reads_from())) + const ModelAction *rf = act->get_reads_from(); + if (rf != NULL && r_modification_order(act, rf)) updated = true; } if (act->is_write()) { @@ -948,10 +981,10 @@ void ModelChecker::post_r_modification_order(ModelAction *curr, const ModelActio action_list_t::reverse_iterator rit; ModelAction *lastact = NULL; - /* Find last action that happens after curr */ + /* Find last action that happens after curr that is either not curr or a rmw */ for (rit = list->rbegin(); rit != list->rend(); rit++) { ModelAction *act = *rit; - if (curr->happens_before(act)) { + if (curr->happens_before(act) && (curr != act || curr->is_rmw())) { lastact = act; } else break; @@ -959,12 +992,25 @@ void ModelChecker::post_r_modification_order(ModelAction *curr, const ModelActio /* Include at most one act per-thread that "happens before" curr */ if (lastact != NULL) { - if (lastact->is_read()) { + if (lastact==curr) { + //Case 1: The resolved read is a RMW, and we need to make sure + //that the write portion of the RMW mod order after rf + + mo_graph->addEdge(rf, lastact); + } else if (lastact->is_read()) { + //Case 2: The resolved read is a normal read and the next + //operation is a read, and we need to make sure the value read + //is mod ordered after rf + const ModelAction *postreadfrom = lastact->get_reads_from(); if (postreadfrom != NULL&&rf != postreadfrom) mo_graph->addEdge(rf, postreadfrom); - } else if (rf != lastact) { - mo_graph->addEdge(rf, lastact); + } else { + //Case 3: The resolved read is a normal read and the next + //operation is a write, and we need to make sure that the + //write is mod ordered after rf + if (lastact!=rf) + mo_graph->addEdge(rf, lastact); } break; } @@ -1288,6 +1334,8 @@ bool ModelChecker::resolve_release_sequences(void *location, work_queue_t *work_ } if (updated) { + /* Re-check all pending release sequences */ + work_queue->push_back(CheckRelSeqWorkEntry(NULL)); /* Re-check act for mo_graph edges */ work_queue->push_back(MOEdgeWorkEntry(act)); @@ -1436,7 +1484,10 @@ bool ModelChecker::resolve_promises(ModelAction *write) //Next fix up the modification order for actions that happened //after the read. post_r_modification_order(read, write); + //Make sure the promise's value matches the write's value + ASSERT(promise->get_value() == write->get_value()); + delete(promise); promises->erase(promises->begin() + promise_index); resolved = true; } else @@ -1570,6 +1621,33 @@ static void print_list(action_list_t *list) printf("---------------------------------------------------------------------\n"); } +#if SUPPORT_MOD_ORDER_DUMP +void ModelChecker::dumpGraph(char *filename) { + char buffer[200]; + sprintf(buffer, "%s.dot",filename); + FILE *file=fopen(buffer, "w"); + fprintf(file, "digraph %s {\n",filename); + mo_graph->dumpNodes(file); + ModelAction ** thread_array=(ModelAction **)model_calloc(1, sizeof(ModelAction *)*get_num_threads()); + + for (action_list_t::iterator it = action_trace->begin(); it != action_trace->end(); it++) { + ModelAction *action=*it; + if (action->is_read()) { + fprintf(file, "N%u [label=\"%u, T%u\"];\n", action->get_seq_number(),action->get_seq_number(), action->get_tid()); + fprintf(file, "N%u -> N%u[label=\"rf\", color=red];\n", action->get_seq_number(), action->get_reads_from()->get_seq_number()); + } + if (thread_array[action->get_tid()] != NULL) { + fprintf(file, "N%u -> N%u[label=\"sb\", color=blue];\n", thread_array[action->get_tid()]->get_seq_number(), action->get_seq_number()); + } + + thread_array[action->get_tid()]=action; + } + fprintf(file,"}\n"); + model_free(thread_array); + fclose(file); +} +#endif + void ModelChecker::print_summary() { printf("\n"); @@ -1582,6 +1660,8 @@ void ModelChecker::print_summary() char buffername[100]; sprintf(buffername, "exec%04u", num_executions); mo_graph->dumpGraphToFile(buffername); + sprintf(buffername, "graph%04u", num_executions); + dumpGraph(buffername); #endif if (!isfinalfeasible()) @@ -1610,12 +1690,35 @@ void ModelChecker::remove_thread(Thread *t) scheduler->remove_thread(t); } +/** + * @brief Get a Thread reference by its ID + * @param tid The Thread's ID + * @return A Thread reference + */ +Thread * ModelChecker::get_thread(thread_id_t tid) +{ + return thread_map->get(id_to_int(tid)); +} + +/** + * @brief Get a reference to the Thread in which a ModelAction was executed + * @param act The ModelAction + * @return A Thread reference + */ +Thread * ModelChecker::get_thread(ModelAction *act) +{ + return get_thread(act->get_tid()); +} + /** * Switch from a user-context to the "master thread" context (a.k.a. system * context). This switch is made with the intention of exploring a particular * model-checking action (described by a ModelAction object). Must be called * from a user-thread context. - * @param act The current action that will be explored. Must not be NULL. + * + * @param act The current action that will be explored. May be NULL only if + * trace is exiting via an assertion (see ModelChecker::set_assert and + * ModelChecker::has_asserted). * @return Return status from the 'swap' call (i.e., success/fail, 0/-1) */ int ModelChecker::switch_to_master(ModelAction *act) @@ -1642,6 +1745,7 @@ bool ModelChecker::take_step() { priv->nextThread = check_current_action(priv->current_action); priv->current_action = NULL; + if (curr->is_blocked() || curr->is_complete()) scheduler->remove_thread(curr); } else {