experiment with exponential decay model
[c11tester.git] / execution.cc
index 87dbe69eeeea320257cda85dc16b905665502529..e1c5e2ddbb06767e13c51d55b230f553d5f2c67d 100644 (file)
@@ -28,7 +28,6 @@ struct model_snapshot_members {
                next_thread_id(INITIAL_THREAD_ID),
                used_sequence_numbers(0),
                bugs(),
-               bad_synchronization(false),
                asserted(false)
        { }
 
@@ -42,7 +41,6 @@ struct model_snapshot_members {
        modelclock_t used_sequence_numbers;
        SnapVector<bug_message *> bugs;
        /** @brief Incorrectly-ordered synchronization was made */
-       bool bad_synchronization;
        bool asserted;
 
        SNAPSHOTALLOC
@@ -73,8 +71,8 @@ ModelExecution::ModelExecution(ModelChecker *m, Scheduler *scheduler) :
        /* Initialize a model-checker thread, for special ModelActions */
        model_thread = new Thread(get_next_id());
        add_thread(model_thread);
-       scheduler->register_engine(this);
        fuzzer->register_engine(m->get_history(), this);
+       scheduler->register_engine(this);
 }
 
 /** @brief Destructor */
@@ -161,6 +159,7 @@ bool ModelExecution::should_wake_up(const ModelAction *curr, const Thread *threa
                if (fence_release && *(get_last_action(thread->get_id())) < *fence_release)
                        return true;
        }
+       /* The sleep is literally sleeping */
        if (asleep->is_sleep()) {
                if (fuzzer->shouldWake(asleep))
                        return true;
@@ -174,29 +173,20 @@ void ModelExecution::wake_up_sleeping_actions(ModelAction *curr)
        for (unsigned int i = 0;i < get_num_threads();i++) {
                Thread *thr = get_thread(int_to_id(i));
                if (scheduler->is_sleep_set(thr)) {
-                       if (should_wake_up(curr, thr))
+                       if (should_wake_up(curr, thr)) {
                                /* Remove this thread from sleep set */
                                scheduler->remove_sleep(thr);
+                               if (thr->get_pending()->is_sleep())
+                                       thr->set_wakeup_state(true);
+                       }
                }
        }
 }
 
-/** @brief Alert the model-checker that an incorrectly-ordered
- * synchronization was made */
-void ModelExecution::set_bad_synchronization()
-{
-       priv->bad_synchronization = true;
-}
-
-bool ModelExecution::assert_bug(const char *msg)
+void ModelExecution::assert_bug(const char *msg)
 {
        priv->bugs.push_back(new bug_message(msg));
-
-       if (isfeasibleprefix()) {
-               set_assert();
-               return true;
-       }
-       return false;
+       set_assert();
 }
 
 /** @return True, if any bugs have been reported for this execution */
@@ -297,10 +287,19 @@ bool ModelExecution::process_read(ModelAction *curr, SnapVector<ModelAction *> *
                rf_set->push_back(nonatomicstore);
        }
 
+       // Remove writes that violate read modification order
+       uint i = 0;
+       while (i < rf_set->size()) {
+               ModelAction * rf = (*rf_set)[i];
+               if (!r_modification_order(curr, rf, NULL, NULL, true)) {
+                       (*rf_set)[i] = rf_set->back();
+                       rf_set->pop_back();
+               } else
+                       i++;
+       }
+
        while(true) {
                int index = fuzzer->selectWrite(curr, rf_set);
-               if (index == -1)        // no feasible write exists
-                       return false;
 
                ModelAction *rf = (*rf_set)[index];
 
@@ -319,6 +318,9 @@ bool ModelExecution::process_read(ModelAction *curr, SnapVector<ModelAction *> *
                        }
                        return true;
                }
+
+               ASSERT(false);
+               /* TODO: Following code not needed anymore */
                priorset->clear();
                (*rf_set)[index] = rf_set->back();
                rf_set->pop_back();
@@ -565,6 +567,12 @@ void ModelExecution::process_thread_action(ModelAction *curr)
        case THREAD_START: {
                break;
        }
+       case THREAD_SLEEP: {
+               Thread *th = get_thread(curr);
+               th->set_pending(curr);
+               scheduler->add_sleep(th);
+               break;
+       }
        default:
                break;
        }
@@ -644,7 +652,7 @@ void ModelExecution::read_from(ModelAction *act, ModelAction *rf)
 bool ModelExecution::synchronize(const ModelAction *first, ModelAction *second)
 {
        if (*second < *first) {
-               set_bad_synchronization();
+               ASSERT(0);      //This should not happend
                return false;
        }
        return second->synchronize_with(first);
@@ -702,7 +710,7 @@ ModelAction * ModelExecution::check_current_action(ModelAction *curr)
        wake_up_sleeping_actions(curr);
 
        /* Add uninitialized actions to lists */
-       if (!second_part_of_rmw && curr->get_type() != NOOP)
+       if (!second_part_of_rmw)
                add_uninit_action_to_lists(curr);
 
        SnapVector<ModelAction *> * rf_set = NULL;
@@ -711,15 +719,13 @@ ModelAction * ModelExecution::check_current_action(ModelAction *curr)
                rf_set = build_may_read_from(curr);
 
        if (curr->is_read() && !second_part_of_rmw) {
-               bool success = process_read(curr, rf_set);
+               process_read(curr, rf_set);
                delete rf_set;
-               if (!success)
-                       return curr;    // Do not add action to lists
        } else
                ASSERT(rf_set == NULL);
 
        /* Add the action to lists */
-       if (!second_part_of_rmw && curr->get_type() != NOOP)
+       if (!second_part_of_rmw)
                add_action_to_lists(curr);
 
        if (curr->is_write())
@@ -739,42 +745,6 @@ ModelAction * ModelExecution::check_current_action(ModelAction *curr)
        return curr;
 }
 
-/**
- * This is the strongest feasibility check available.
- * @return whether the current trace (partial or complete) must be a prefix of
- * a feasible trace.
- */
-bool ModelExecution::isfeasibleprefix() const
-{
-       return !is_infeasible();
-}
-
-/**
- * Print disagnostic information about an infeasible execution
- * @param prefix A string to prefix the output with; if NULL, then a default
- * message prefix will be provided
- */
-void ModelExecution::print_infeasibility(const char *prefix) const
-{
-       char buf[100];
-       char *ptr = buf;
-       if (priv->bad_synchronization)
-               ptr += sprintf(ptr, "[bad sw ordering]");
-       if (ptr != buf)
-               model_print("%s: %s", prefix ? prefix : "Infeasible", buf);
-}
-
-/**
- * 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 ModelExecution::is_infeasible() const
-{
-       return priv->bad_synchronization;
-}
-
 /** Close out a RMWR by converting previous RMWR into a RMW or READ. */
 ModelAction * ModelExecution::process_rmw(ModelAction *act) {
        ModelAction *lastread = get_last_action(act->get_tid());
@@ -799,10 +769,14 @@ ModelAction * ModelExecution::process_rmw(ModelAction *act) {
  *
  * @param curr The current action. Must be a read.
  * @param rf The ModelAction or Promise that curr reads from. Must be a write.
+ * @param check_only If true, then only check whether the current action satisfies
+ *        read modification order or not, without modifiying priorset and canprune.
+ *        False by default.
  * @return True if modification order edges were added; false otherwise
  */
 
-bool ModelExecution::r_modification_order(ModelAction *curr, const ModelAction *rf, SnapVector<const ModelAction *> * priorset, bool * canprune)
+bool ModelExecution::r_modification_order(ModelAction *curr, const ModelAction *rf,
+                                                                                                                                                                       SnapVector<const ModelAction *> * priorset, bool * canprune, bool check_only)
 {
        SnapVector<action_list_t> *thrd_lists = obj_thrd_map.get(curr->get_location());
        unsigned int i;
@@ -855,7 +829,8 @@ bool ModelExecution::r_modification_order(ModelAction *curr, const ModelAction *
                                                *act < *last_sc_fence_thread_local) {
                                        if (mo_graph->checkReachable(rf, act))
                                                return false;
-                                       priorset->push_back(act);
+                                       if (!check_only)
+                                               priorset->push_back(act);
                                        break;
                                }
                                /* C++, Section 29.3 statement 4 */
@@ -863,7 +838,8 @@ bool ModelExecution::r_modification_order(ModelAction *curr, const ModelAction *
                                                                 *act < *last_sc_fence_local) {
                                        if (mo_graph->checkReachable(rf, act))
                                                return false;
-                                       priorset->push_back(act);
+                                       if (!check_only)
+                                               priorset->push_back(act);
                                        break;
                                }
                                /* C++, Section 29.3 statement 6 */
@@ -871,7 +847,8 @@ bool ModelExecution::r_modification_order(ModelAction *curr, const ModelAction *
                                                                 *act < *last_sc_fence_thread_before) {
                                        if (mo_graph->checkReachable(rf, act))
                                                return false;
-                                       priorset->push_back(act);
+                                       if (!check_only)
+                                               priorset->push_back(act);
                                        break;
                                }
                        }
@@ -890,17 +867,20 @@ bool ModelExecution::r_modification_order(ModelAction *curr, const ModelAction *
                                if (act->is_write()) {
                                        if (mo_graph->checkReachable(rf, act))
                                                return false;
-                                       priorset->push_back(act);
+                                       if (!check_only)
+                                               priorset->push_back(act);
                                } else {
                                        const ModelAction *prevrf = act->get_reads_from();
                                        if (!prevrf->equals(rf)) {
                                                if (mo_graph->checkReachable(rf, prevrf))
                                                        return false;
-                                               priorset->push_back(prevrf);
+                                               if (!check_only)
+                                                       priorset->push_back(prevrf);
                                        } else {
                                                if (act->get_tid() == curr->get_tid()) {
                                                        //Can prune curr from obj list
-                                                       *canprune = true;
+                                                       if (!check_only)
+                                                               *canprune = true;
                                                }
                                        }
                                }
@@ -1136,7 +1116,7 @@ void ModelExecution::add_uninit_action_to_lists(ModelAction *act)
                if ((int)vec->size() <= uninit_id) {
                        int oldsize = (int) vec->size();
                        vec->resize(uninit_id + 1);
-                       for(int i = oldsize; i < uninit_id + 1; i++) {
+                       for(int i = oldsize;i < uninit_id + 1;i++) {
                                new (&(*vec)[i]) action_list_t();
                        }
                }
@@ -1152,7 +1132,7 @@ void ModelExecution::add_uninit_action_to_lists(ModelAction *act)
        if ((int)vec->size() <= tid) {
                uint oldsize = vec->size();
                vec->resize(priv->next_thread_id);
-               for(uint i = oldsize; i < priv->next_thread_id; i++)
+               for(uint i = oldsize;i < priv->next_thread_id;i++)
                        new (&(*vec)[i]) action_list_t();
        }
        if (uninit)
@@ -1187,7 +1167,7 @@ void ModelExecution::add_action_to_lists(ModelAction *act)
        if ((int)vec->size() <= tid) {
                uint oldsize = vec->size();
                vec->resize(priv->next_thread_id);
-               for(uint i = oldsize; i < priv->next_thread_id; i++)
+               for(uint i = oldsize;i < priv->next_thread_id;i++)
                        new (&(*vec)[i]) action_list_t();
        }
        (*vec)[tid].push_back(act);
@@ -1212,7 +1192,7 @@ void ModelExecution::add_action_to_lists(ModelAction *act)
                if ((int)vec->size() <= tid) {
                        uint oldsize = vec->size();
                        vec->resize(priv->next_thread_id);
-                       for(uint i = oldsize; i < priv->next_thread_id; i++)
+                       for(uint i = oldsize;i < priv->next_thread_id;i++)
                                new (&(*vec)[i]) action_list_t();
                }
                (*vec)[tid].push_back(act);
@@ -1585,13 +1565,11 @@ void ModelExecution::print_summary()
 #endif
 
        model_print("Execution trace %d:", get_execution_number());
-       if (isfeasibleprefix()) {
-               if (scheduler->all_threads_sleeping())
-                       model_print(" SLEEP-SET REDUNDANT");
-               if (have_bug_reports())
-                       model_print(" DETECTED BUG(S)");
-       } else
-               print_infeasibility(" INFEASIBLE");
+       if (scheduler->all_threads_sleeping())
+               model_print(" SLEEP-SET REDUNDANT");
+       if (have_bug_reports())
+               model_print(" DETECTED BUG(S)");
+
        model_print("\n");
 
        print_list(&action_trace);