#include "promise.h"
#include "datarace.h"
#include "mutex.h"
+#include "threads.h"
#define INITIAL_THREAD_ID 0
num_executions(0),
num_feasible_executions(0),
diverge(NULL),
+ earliest_diverge(NULL),
action_trace(new action_list_t()),
thread_map(new HashTable<int, Thread *, int>()),
obj_map(new HashTable<const void *, action_list_t, uintptr_t, 4>()),
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()
{
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()) {
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();
}
- DEBUG("*** ModelChecker chose next thread = %d ***\n", tid);
+ DEBUG("*** ModelChecker chose next thread = %d ***\n", id_to_int(tid));
ASSERT(tid != THREAD_ID_T_NONE);
return thread_map->get(id_to_int(tid));
}
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();
if (!node->set_backtrack(tid))
continue;
DEBUG("Setting backtrack: conflict = %d, instead tid = %d\n",
- prev->get_tid(), t->get_id());
+ id_to_int(prev->get_tid()),
+ id_to_int(t->get_id()));
if (DBG_ENABLED()) {
prev->print();
act->print();
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;
* (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: {
scheduler->sleep(waiting);
} else {
do_complete_join(curr);
- synchronized = true;
+ updated = true; /* trigger rel-seq checks */
}
break;
}
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: {
break;
}
- return synchronized;
+ return updated;
}
/**
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 */
/* 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);
}
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()) {
/** Close out a RMWR by converting previous RMWR into a RMW or READ. */
ModelAction * ModelChecker::process_rmw(ModelAction *act) {
- int tid = id_to_int(act->get_tid());
- ModelAction *lastread = get_last_action(tid);
+ ModelAction *lastread = get_last_action(act->get_tid());
lastread->process_rmw(act);
if (act->is_rmw() && lastread->get_reads_from()!=NULL) {
mo_graph->addRMWEdge(lastread->get_reads_from(), lastread);
}
} else {
const ModelAction *prevreadfrom = act->get_reads_from();
- if (prevreadfrom != NULL && rf != prevreadfrom) {
+ //if the previous read is unresolved, keep going...
+ if (prevreadfrom == NULL)
+ continue;
+
+ if (rf != prevreadfrom) {
mo_graph->addEdge(prevreadfrom, rf);
added = true;
}
ModelAction *act = *rit;
if (act == curr) {
/*
- * If RMW, we already have all relevant edges,
- * so just skip to next thread.
- * If normal write, we need to look at earlier
- * actions, so continue processing list.
+ * 1) If RMW and it actually read from something, then we
+ * already have all relevant edges, so just skip to next
+ * thread.
+ *
+ * 2) If RMW and it didn't read from anything, we should
+ * whatever edge we can get to speed up convergence.
+ *
+ * 3) If normal write, we need to look at earlier actions, so
+ * continue processing list.
*/
- if (curr->is_rmw())
- break;
- else
+ if (curr->is_rmw()) {
+ if (curr->get_reads_from()!=NULL)
+ break;
+ else
+ continue;
+ } else
continue;
}
*/
if (act->is_write())
mo_graph->addEdge(act, curr);
- else if (act->is_read() && act->get_reads_from() != NULL)
+ else if (act->is_read()) {
+ //if previous read accessed a null, just keep going
+ if (act->get_reads_from() == NULL)
+ continue;
mo_graph->addEdge(act->get_reads_from(), curr);
+ }
added = true;
break;
} else if (act->is_read() && !act->is_synchronizing(curr) &&
ModelAction *last = get_last_action(int_to_id(i));
if (last && (rf->happens_before(last) ||
- last->get_type() == THREAD_FINISH))
+ get_thread(int_to_id(i))->is_complete()))
future_ordered = true;
for (rit = list->rbegin(); rit != list->rend(); rit++) {
}
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));
//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
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());
+ if (action->get_reads_from()!=NULL)
+ 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");
char buffername[100];
sprintf(buffername, "exec%04u", num_executions);
mo_graph->dumpGraphToFile(buffername);
+ sprintf(buffername, "graph%04u", num_executions);
+ dumpGraph(buffername);
#endif
if (!isfinalfeasible())
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) const
+{
+ 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) const
+{
+ 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)
if (has_asserted())
return false;
- Thread * curr = thread_current();
+ Thread *curr = thread_current();
if (curr) {
if (curr->get_state() == THREAD_READY) {
ASSERT(priv->current_action);
ASSERT(false);
}
}
- Thread * next = scheduler->next_thread(priv->nextThread);
+ Thread *next = scheduler->next_thread(priv->nextThread);
/* Infeasible -> don't take any more steps */
if (!isfeasible())
return false;
- if (next)
- next->set_state(THREAD_RUNNING);
- DEBUG("(%d, %d)\n", curr ? curr->get_id() : -1, next ? next->get_id() : -1);
+ DEBUG("(%d, %d)\n", curr ? id_to_int(curr->get_id()) : -1,
+ next ? id_to_int(next->get_id()) : -1);
/* next == NULL -> don't take any more steps */
if (!next)
return false;
- if ( next->get_pending() != NULL ) {
- //restart a pending action
+ next->set_state(THREAD_RUNNING);
+
+ if (next->get_pending() != NULL) {
+ /* restart a pending action */
set_current_action(next->get_pending());
next->set_pending(NULL);
next->set_state(THREAD_READY);
projects / model-checker.git / blobdiff