changes to allow running programs with racing initialization...
[model-checker.git] / model.cc
index a96a79c851ee83b5624df3bdafda7487802bf5b1..f8aa4f0a4fd49b6eb487539c9fece2d15146e2a0 100644 (file)
--- a/model.cc
+++ b/model.cc
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <algorithm>
+#include <mutex>
 
 #include "model.h"
 #include "action.h"
@@ -11,7 +12,6 @@
 #include "cyclegraph.h"
 #include "promise.h"
 #include "datarace.h"
-#include "mutex.h"
 #include "threads-model.h"
 
 #define INITIAL_THREAD_ID      0
@@ -31,6 +31,7 @@ ModelChecker::ModelChecker(struct model_params params) :
        thread_map(new HashTable<int, Thread *, int>()),
        obj_map(new HashTable<const void *, action_list_t, uintptr_t, 4>()),
        lock_waiters_map(new HashTable<const void *, action_list_t, uintptr_t, 4>()),
+       condvar_waiters_map(new HashTable<const void *, action_list_t, uintptr_t, 4>()),
        obj_thrd_map(new HashTable<void *, std::vector<action_list_t>, uintptr_t, 4 >()),
        promises(new std::vector< Promise *, SnapshotAlloc<Promise *> >()),
        futurevalues(new std::vector< struct PendingFutureValue, SnapshotAlloc<struct PendingFutureValue> >()),
@@ -63,6 +64,7 @@ ModelChecker::~ModelChecker()
        delete obj_thrd_map;
        delete obj_map;
        delete lock_waiters_map;
+       delete condvar_waiters_map;
        delete action_trace;
 
        for (unsigned int i = 0; i < promises->size(); i++)
@@ -162,7 +164,11 @@ Thread * ModelChecker::get_next_thread(ModelAction *curr)
                scheduler->update_sleep_set(prevnode);
 
                /* Reached divergence point */
-               if (nextnode->increment_promise()) {
+               if (nextnode->increment_misc()) {
+                       /* The next node will try to satisfy a different misc_index values. */
+                       tid = next->get_tid();
+                       node_stack->pop_restofstack(2);
+               } else if (nextnode->increment_promise()) {
                        /* The next node will try to satisfy a different set of promises. */
                        tid = next->get_tid();
                        node_stack->pop_restofstack(2);
@@ -319,6 +325,32 @@ ModelAction * ModelChecker::get_last_conflict(ModelAction *act)
                }
                break;
        }
+       case ATOMIC_WAIT: {
+               /* linear search: from most recent to oldest */
+               action_list_t *list = obj_map->get_safe_ptr(act->get_location());
+               action_list_t::reverse_iterator rit;
+               for (rit = list->rbegin(); rit != list->rend(); rit++) {
+                       ModelAction *prev = *rit;
+                       if (!act->same_thread(prev)&&prev->is_failed_trylock())
+                               return prev;
+                       if (!act->same_thread(prev)&&prev->is_notify())
+                               return prev;
+               }
+               break;
+       }
+
+       case ATOMIC_NOTIFY_ALL:
+       case ATOMIC_NOTIFY_ONE: {
+               /* linear search: from most recent to oldest */
+               action_list_t *list = obj_map->get_safe_ptr(act->get_location());
+               action_list_t::reverse_iterator rit;
+               for (rit = list->rbegin(); rit != list->rend(); rit++) {
+                       ModelAction *prev = *rit;
+                       if (!act->same_thread(prev)&&prev->is_wait())
+                               return prev;
+               }
+               break;
+       }
        default:
                break;
        }
@@ -466,8 +498,17 @@ bool ModelChecker::process_read(ModelAction *curr, bool second_part_of_rmw)
  * @return True if synchronization was updated; false otherwise
  */
 bool ModelChecker::process_mutex(ModelAction *curr) {
-       std::mutex *mutex = (std::mutex *)curr->get_location();
-       struct std::mutex_state *state = mutex->get_state();
+       std::mutex *mutex=NULL;
+       struct std::mutex_state *state=NULL;
+
+       if (curr->is_trylock() || curr->is_lock() || curr->is_unlock()) {
+               mutex = (std::mutex *)curr->get_location();
+               state = mutex->get_state();
+       } else if(curr->is_wait()) {
+               mutex = (std::mutex *)curr->get_value();
+               state = mutex->get_state();
+       }
+
        switch (curr->get_type()) {
        case ATOMIC_TRYLOCK: {
                bool success = !state->islocked;
@@ -505,6 +546,43 @@ bool ModelChecker::process_mutex(ModelAction *curr) {
                waiters->clear();
                break;
        }
+       case ATOMIC_WAIT: {
+               //unlock the lock
+               state->islocked = false;
+               //wake up the other threads
+               action_list_t *waiters = lock_waiters_map->get_safe_ptr((void *) curr->get_value());
+               //activate all the waiting threads
+               for (action_list_t::iterator rit = waiters->begin(); rit != waiters->end(); rit++) {
+                       scheduler->wake(get_thread(*rit));
+               }
+               waiters->clear();
+               //check whether we should go to sleep or not...simulate spurious failures
+               if (curr->get_node()->get_misc()==0) {
+                       condvar_waiters_map->get_safe_ptr(curr->get_location())->push_back(curr);
+                       //disable us
+                       scheduler->sleep(get_current_thread());
+               }
+               break;
+       }
+       case ATOMIC_NOTIFY_ALL: {
+               action_list_t *waiters = condvar_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->wake(get_thread(*rit));
+               }
+               waiters->clear();
+               break;
+       }
+       case ATOMIC_NOTIFY_ONE: {
+               action_list_t *waiters = condvar_waiters_map->get_safe_ptr(curr->get_location());
+               int wakeupthread=curr->get_node()->get_misc();
+               action_list_t::iterator it = waiters->begin();
+               advance(it, wakeupthread);
+               scheduler->wake(get_thread(*it));
+               waiters->erase(it);
+               break;
+       }
+
        default:
                ASSERT(0);
        }
@@ -712,6 +790,11 @@ ModelAction * ModelChecker::initialize_curr_action(ModelAction *curr)
                        compute_promises(newcurr);
                else if (newcurr->is_relseq_fixup())
                        compute_relseq_breakwrites(newcurr);
+               else if (newcurr->is_wait())
+                       newcurr->get_node()->set_misc_max(2);
+               else if (newcurr->is_notify_one()) {
+                       newcurr->get_node()->set_misc_max(condvar_waiters_map->get_safe_ptr(newcurr->get_location())->size());
+               }
        }
        return newcurr;
 }
@@ -856,6 +939,7 @@ void ModelChecker::check_curr_backtracking(ModelAction * curr) {
        Node *parnode = currnode->get_parent();
 
        if ((!parnode->backtrack_empty() ||
+                        !currnode->misc_empty() ||
                         !currnode->read_from_empty() ||
                         !currnode->future_value_empty() ||
                         !currnode->promise_empty() ||
@@ -1425,8 +1509,8 @@ bool ModelChecker::release_seq_heads(const ModelAction *rf,
                                continue;
                        }
 
-                       /* Only writes can break release sequences */
-                       if (!act->is_write())
+                       /* Only non-RMW writes can break release sequences */
+                       if (!act->is_write() || act->is_rmw())
                                continue;
 
                        /* Check modification order */
@@ -1582,6 +1666,20 @@ void ModelChecker::add_action_to_lists(ModelAction *act)
        if ((int)thrd_last_action->size() <= tid)
                thrd_last_action->resize(get_num_threads());
        (*thrd_last_action)[tid] = act;
+
+       if (act->is_wait()) {
+               void *mutex_loc=(void *) act->get_value();
+               obj_map->get_safe_ptr(mutex_loc)->push_back(act);
+       
+               std::vector<action_list_t> *vec = obj_thrd_map->get_safe_ptr(mutex_loc);
+               if (tid >= (int)vec->size())
+                       vec->resize(priv->next_thread_id);
+               (*vec)[tid].push_back(act);
+
+               if ((int)thrd_last_action->size() <= tid)
+                       thrd_last_action->resize(get_num_threads());
+               (*thrd_last_action)[tid] = act;
+       }
 }
 
 /**
@@ -1633,7 +1731,7 @@ ModelAction * ModelChecker::get_last_unlock(ModelAction *curr) const
        /* Find: max({i in dom(S) | isUnlock(t_i) && samevar(t_i, t)}) */
        action_list_t::reverse_iterator rit;
        for (rit = list->rbegin(); rit != list->rend(); rit++)
-               if ((*rit)->is_unlock())
+               if ((*rit)->is_unlock() || (*rit)->is_wait())
                        return *rit;
        return NULL;
 }
@@ -1717,6 +1815,7 @@ void ModelChecker::compute_promises(ModelAction *curr)
                                act->is_read() &&
                                !act->could_synchronize_with(curr) &&
                                !act->same_thread(curr) &&
+                               act->get_location() == curr->get_location() &&
                                promise->get_value() == curr->get_value()) {
                        curr->get_node()->set_promise(i);
                }
@@ -1895,6 +1994,7 @@ void ModelChecker::build_reads_from_past(ModelAction *curr)
        if (!initialized) {
                /** @todo Need a more informative way of reporting errors. */
                printf("ERROR: may read from uninitialized atomic\n");
+               set_assert();
        }
 
        if (DBG_ENABLED() || !initialized) {
@@ -1904,8 +2004,6 @@ void ModelChecker::build_reads_from_past(ModelAction *curr)
                curr->get_node()->print_may_read_from();
                printf("End printing may_read_from\n");
        }
-
-       ASSERT(initialized);
 }
 
 bool ModelChecker::sleep_can_read_from(ModelAction * curr, const ModelAction *write) {