X-Git-Url: http://plrg.eecs.uci.edu/git/?p=c11tester.git;a=blobdiff_plain;f=model.cc;h=da68074240d9ea2b416b40665ef7843d2c7df7ae;hp=691cd72bbbbd5275473ddf0993f70138256a0f0b;hb=7a0167d52294a9707f81a54d74009c6f82346d18;hpb=14653dd20b5fee25e5077ce6a154022fc9f85ce7 diff --git a/model.cc b/model.cc index 691cd72b..da680742 100644 --- a/model.cc +++ b/model.cc @@ -37,6 +37,27 @@ struct bug_message { * Structure for holding small ModelChecker members that should be snapshotted */ struct model_snapshot_members { + model_snapshot_members() : + current_action(NULL), + /* First thread created will have id INITIAL_THREAD_ID */ + next_thread_id(INITIAL_THREAD_ID), + used_sequence_numbers(0), + nextThread(NULL), + next_backtrack(NULL), + bugs(), + stats(), + failed_promise(false), + too_many_reads(false), + bad_synchronization(false), + asserted(false) + { } + + ~model_snapshot_members() { + for (unsigned int i = 0; i < bugs.size(); i++) + delete bugs[i]; + bugs.clear(); + } + ModelAction *current_action; unsigned int next_thread_id; modelclock_t used_sequence_numbers; @@ -44,6 +65,13 @@ struct model_snapshot_members { ModelAction *next_backtrack; std::vector< bug_message *, SnapshotAlloc > bugs; struct execution_stats stats; + bool failed_promise; + bool too_many_reads; + /** @brief Incorrectly-ordered synchronization was made */ + bool bad_synchronization; + bool asserted; + + SNAPSHOTALLOC }; /** @brief Constructor */ @@ -64,17 +92,9 @@ ModelChecker::ModelChecker(struct model_params params) : pending_rel_seqs(new std::vector< struct release_seq *, SnapshotAlloc >()), thrd_last_action(new std::vector< ModelAction *, SnapshotAlloc >(1)), node_stack(new NodeStack()), - mo_graph(new CycleGraph()), - failed_promise(false), - too_many_reads(false), - asserted(false), - bad_synchronization(false) + priv(new struct model_snapshot_members()), + mo_graph(new CycleGraph()) { - /* Allocate this "size" on the snapshotting heap */ - priv = (struct model_snapshot_members *)snapshot_calloc(1, sizeof(*priv)); - /* First thread created will have id INITIAL_THREAD_ID */ - priv->next_thread_id = INITIAL_THREAD_ID; - /* Initialize a model-checker thread, for special ModelActions */ model_thread = new Thread(get_next_id()); thread_map->put(id_to_int(model_thread->get_id()), model_thread); @@ -103,11 +123,7 @@ ModelChecker::~ModelChecker() delete node_stack; delete scheduler; delete mo_graph; - - for (unsigned int i = 0; i < priv->bugs.size(); i++) - delete priv->bugs[i]; - priv->bugs.clear(); - snapshot_free(priv); + delete priv; } static action_list_t * get_safe_ptr_action(HashTable * hash, void * ptr) { @@ -136,10 +152,6 @@ void ModelChecker::reset_to_initial_state() { DEBUG("+++ Resetting to initial state +++\n"); node_stack->reset_execution(); - failed_promise = false; - too_many_reads = false; - bad_synchronization = false; - reset_asserted(); /* Print all model-checker output before rollback */ fflush(model_out); @@ -297,6 +309,23 @@ void ModelChecker::wake_up_sleeping_actions(ModelAction * curr) { } } +/** @brief Alert the model-checker that an incorrectly-ordered + * synchronization was made */ +void ModelChecker::set_bad_synchronization() +{ + priv->bad_synchronization = true; +} + +bool ModelChecker::has_asserted() const +{ + return priv->asserted; +} + +void ModelChecker::set_assert() +{ + priv->asserted = true; +} + /** * Check if we are in a deadlock. Should only be called at the end of an * execution, although it should not give false positives in the middle of an @@ -395,24 +424,54 @@ void ModelChecker::print_bugs() const void ModelChecker::record_stats() { stats.num_total++; - if (!isfinalfeasible()) + if (!isfeasibleprefix()) stats.num_infeasible++; else if (have_bug_reports()) stats.num_buggy_executions++; else if (is_complete_execution()) stats.num_complete++; + else + stats.num_redundant++; } /** @brief Print execution stats */ 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); model_print("Total nodes created: %d\n", node_stack->get_total_nodes()); } +/** + * @brief End-of-exeuction print + * @param printbugs Should any existing bugs be printed? + */ +void ModelChecker::print_execution(bool printbugs) const +{ + print_program_output(); + + if (DBG_ENABLED() || 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"); + print_stats(); + } + + /* Don't print invalid bugs */ + if (printbugs) + print_bugs(); + + model_print("\n"); + print_summary(); +} + /** * Queries the model-checker for more executions to explore and, if one * exists, resets the model-checker state to execute a new execution. @@ -423,44 +482,28 @@ void ModelChecker::print_stats() const bool ModelChecker::next_execution() { DBG(); + /* Is this execution a feasible execution that's worth bug-checking? */ + bool complete = isfeasibleprefix() && (is_complete_execution() || + have_bug_reports()); - if (isfinalfeasible() && (is_complete_execution() || have_bug_reports())) { + /* End-of-execution bug checks */ + if (complete) { if (is_deadlocked()) assert_bug("Deadlock detected"); checkDataRaces(); + } - if (DBG_ENABLED() || params.verbose || have_bug_reports()) { - print_program_output(); - - if (DBG_ENABLED() || 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"); - print_stats(); - } - - print_bugs(); - model_print("\n"); - print_summary(); - } else - clear_program_output(); + record_stats(); - earliest_diverge = NULL; - } else if (DBG_ENABLED()) { - print_program_output(); - model_print("\n"); - print_stats(); - print_summary(); - } else { + /* Output */ + if (DBG_ENABLED() || params.verbose || have_bug_reports()) + print_execution(complete); + else clear_program_output(); - } - record_stats(); + if (complete) + earliest_diverge = NULL; if ((diverge = get_next_backtrack()) == NULL) return false; @@ -480,6 +523,9 @@ ModelAction * ModelChecker::get_last_conflict(ModelAction *act) case ATOMIC_READ: case ATOMIC_WRITE: case ATOMIC_RMW: { + /* Optimization: relaxed operations don't need backtracking */ + if (act->is_relaxed()) + return NULL; /* linear search: from most recent to oldest */ action_list_t *list = get_safe_ptr_action(obj_map, act->get_location()); action_list_t::reverse_iterator rit; @@ -649,9 +695,9 @@ bool ModelChecker::process_read(ModelAction *curr, bool second_part_of_rmw) } - if (!second_part_of_rmw&&!isfeasible()&&(curr->get_node()->increment_read_from()||curr->get_node()->increment_future_value())) { + if (!second_part_of_rmw&&is_infeasible()&&(curr->get_node()->increment_read_from()||curr->get_node()->increment_future_value())) { mo_graph->rollbackChanges(); - too_many_reads = false; + priv->too_many_reads = false; continue; } @@ -1164,48 +1210,67 @@ bool ModelChecker::promises_expired() const return false; } -/** @return whether the current partial trace must be a prefix of a - * feasible trace. */ +/** + * This is the strongest feasibility check available. + * @return whether the current trace (partial or complete) must be a prefix of + * a feasible trace. + */ bool ModelChecker::isfeasibleprefix() const { - return promises->size() == 0 && pending_rel_seqs->size() == 0 && isfeasible(); + return pending_rel_seqs->size() == 0 && is_feasible_prefix_ignore_relseq(); } -/** @return whether the current partial trace is feasible. */ -bool ModelChecker::isfeasible() const +/** + * Returns whether the current completed trace is feasible, except for pending + * release sequences. + */ +bool ModelChecker::is_feasible_prefix_ignore_relseq() const +{ + if (DBG_ENABLED() && promises->size() != 0) + DEBUG("Infeasible: unrevolved promises\n"); + + return !is_infeasible() && promises->size() == 0; +} + +/** + * Check if the current partial trace is infeasible. Does not check any + * end-of-execution flags, which might rule out the execution. Thus, this is + * useful only for ruling an execution as infeasible. + * @return whether the current partial trace is infeasible. + */ +bool ModelChecker::is_infeasible() const { if (DBG_ENABLED() && mo_graph->checkForRMWViolation()) DEBUG("Infeasible: RMW violation\n"); - return !mo_graph->checkForRMWViolation() && isfeasibleotherthanRMW(); + return mo_graph->checkForRMWViolation() || is_infeasible_ignoreRMW(); } -/** @return whether the current partial trace is feasible other than - * multiple RMW reading from the same store. */ -bool ModelChecker::isfeasibleotherthanRMW() const +/** + * Check If the current partial trace is infeasible, while ignoring + * infeasibility related to 2 RMW's reading from the same store. It does not + * check end-of-execution feasibility. + * @see ModelChecker::is_infeasible + * @return whether the current partial trace is infeasible, ignoring multiple + * RMWs reading from the same store. + * */ +bool ModelChecker::is_infeasible_ignoreRMW() const { if (DBG_ENABLED()) { if (mo_graph->checkForCycles()) DEBUG("Infeasible: modification order cycles\n"); - if (failed_promise) + if (priv->failed_promise) DEBUG("Infeasible: failed promise\n"); - if (too_many_reads) + if (priv->too_many_reads) DEBUG("Infeasible: too many reads\n"); - if (bad_synchronization) + if (priv->bad_synchronization) DEBUG("Infeasible: bad synchronization ordering\n"); if (promises_expired()) DEBUG("Infeasible: promises expired\n"); } - return !mo_graph->checkForCycles() && !failed_promise && !too_many_reads && !bad_synchronization && !promises_expired(); -} - -/** Returns whether the current completed trace is feasible. */ -bool ModelChecker::isfinalfeasible() const -{ - if (DBG_ENABLED() && promises->size() != 0) - DEBUG("Infeasible: unrevolved promises\n"); - - return isfeasible() && promises->size() == 0; + return mo_graph->checkForCycles() || priv->failed_promise || + priv->too_many_reads || priv->bad_synchronization || + promises_expired(); } /** Close out a RMWR by converting previous RMWR into a RMW or READ. */ @@ -1237,7 +1302,7 @@ void ModelChecker::check_recency(ModelAction *curr, const ModelAction *rf) { return; //Must make sure that execution is currently feasible... We could //accidentally clear by rolling back - if (!isfeasible()) + if (is_infeasible()) return; std::vector *thrd_lists = get_safe_ptr_vect_action(obj_thrd_map, curr->get_location()); int tid = id_to_int(curr->get_tid()); @@ -1280,7 +1345,7 @@ void ModelChecker::check_recency(ModelAction *curr, const ModelAction *rf) { /* Test to see whether this is a feasible write to read from*/ mo_graph->startChanges(); r_modification_order(curr, write); - bool feasiblereadfrom = isfeasible(); + bool feasiblereadfrom = !is_infeasible(); mo_graph->rollbackChanges(); if (!feasiblereadfrom) @@ -1305,7 +1370,7 @@ void ModelChecker::check_recency(ModelAction *curr, const ModelAction *rf) { } } if (feasiblewrite) { - too_many_reads = true; + priv->too_many_reads = true; return; } } @@ -1540,8 +1605,8 @@ bool ModelChecker::w_modification_order(ModelAction *curr) */ if (thin_air_constraint_may_allow(curr, act)) { - if (isfeasible() || - (curr->is_rmw() && act->is_rmw() && curr->get_reads_from() == act->get_reads_from() && isfeasibleotherthanRMW())) { + if (!is_infeasible() || + (curr->is_rmw() && act->is_rmw() && curr->get_reads_from() == act->get_reads_from() && !is_infeasible_ignoreRMW())) { struct PendingFutureValue pfv = {curr,act}; futurevalues->push_back(pfv); } @@ -2047,7 +2112,7 @@ void ModelChecker::check_promises(thread_id_t tid, ClockVector *old_cv, ClockVec merge_cv->synchronized_since(act)) { if (promise->increment_threads(tid)) { //Promise has failed - failed_promise = true; + priv->failed_promise = true; return; } } @@ -2058,7 +2123,7 @@ void ModelChecker::check_promises_thread_disabled() { for (unsigned int i = 0; i < promises->size(); i++) { Promise *promise = (*promises)[i]; if (promise->check_promise()) { - failed_promise = true; + priv->failed_promise = true; return; } } @@ -2109,12 +2174,12 @@ void ModelChecker::mo_check_promises(thread_id_t tid, const ModelAction *write) promise->set_write(write); //The pwrite cannot happen before the promise if (write->happens_before(act) && (write != act)) { - failed_promise = true; + priv->failed_promise = true; return; } } if (mo_graph->checkPromise(write, promise)) { - failed_promise = true; + priv->failed_promise = true; return; } } @@ -2125,7 +2190,7 @@ void ModelChecker::mo_check_promises(thread_id_t tid, const ModelAction *write) if (promise->get_write()&&mo_graph->checkReachable(promise->get_write(), write)) { if (promise->increment_threads(tid)) { - failed_promise = true; + priv->failed_promise = true; return; } } @@ -2299,7 +2364,7 @@ void ModelChecker::print_summary() const dumpGraph(buffername); #endif - if (!isfinalfeasible()) + if (!isfeasibleprefix()) model_print("INFEASIBLE EXECUTION!\n"); print_list(action_trace, stats.num_total); model_print("\n"); @@ -2410,7 +2475,7 @@ bool ModelChecker::take_step() { Thread *next = scheduler->next_thread(priv->nextThread); /* Infeasible -> don't take any more steps */ - if (!isfeasible()) + if (is_infeasible()) return false; else if (isfeasibleprefix() && have_bug_reports()) { set_assert(); @@ -2436,7 +2501,7 @@ bool ModelChecker::take_step() { * (4) no pending promises */ if (!pending_rel_seqs->empty() && (!next || next->is_model_thread()) && - isfinalfeasible() && !unrealizedraces.empty()) { + is_feasible_prefix_ignore_relseq() && !unrealizedraces.empty()) { model_print("*** WARNING: release sequence fixup action (%zu pending release seuqences) ***\n", pending_rel_seqs->size()); ModelAction *fixup = new ModelAction(MODEL_FIXUP_RELSEQ, @@ -2464,9 +2529,24 @@ bool ModelChecker::take_step() { return (Thread::swap(&system_context, next) == 0); } -/** Runs the current execution until threre are no more steps to take. */ -void ModelChecker::finish_execution() { - DBG(); +/** 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 Run ModelChecker for the user program */ +void ModelChecker::run() +{ + do { + thrd_t user_thread; + + /* Start user program */ + add_thread(new Thread(&user_thread, &user_main_wrapper, NULL)); + + /* Wait for all threads to complete */ + while (take_step()); + } while (next_execution()); - while (take_step()); + print_stats(); }