action_trace(),
thread_map(2), /* We'll always need at least 2 threads */
pthread_map(0),
- pthread_counter(0),
+ pthread_counter(1),
obj_map(),
condvar_waiters_map(),
obj_thrd_map(),
thrd_last_fence_release(),
node_stack(node_stack),
priv(new struct model_snapshot_members ()),
- mo_graph(new CycleGraph()),
+ mo_graph(new CycleGraph()),
fuzzer(new Fuzzer())
{
/* Initialize a model-checker thread, for special ModelActions */
* @param rf_set is the set of model actions we can possibly read from
* @return True if processing this read updates the mo_graph.
*/
-void ModelExecution::process_read(ModelAction *curr, SnapVector<const ModelAction *> * rf_set)
+void ModelExecution::process_read(ModelAction *curr, SnapVector<ModelAction *> * rf_set)
{
SnapVector<const ModelAction *> * priorset = new SnapVector<const ModelAction *>();
while(true) {
int index = fuzzer->selectWrite(curr, rf_set);
- const ModelAction *rf = (*rf_set)[index];
+ ModelAction *rf = (*rf_set)[index];
ASSERT(rf);
get_thread(curr)->set_return_value(curr->get_return_value());
delete priorset;
if (canprune && curr->get_type() == ATOMIC_READ) {
- int tid = id_to_int(curr->get_tid());
- (*obj_thrd_map.get(curr->get_location()))[tid].pop_back();
+ int tid = id_to_int(curr->get_tid());
+ (*obj_thrd_map.get(curr->get_location()))[tid].pop_back();
}
return;
}
}
case ATOMIC_WAIT:
case ATOMIC_UNLOCK: {
+ //TODO: FIX WAIT SITUATION...WAITS CAN SPURIOUSLY FAIL...TIMED WAITS SHOULD PROBABLY JUST BE THE SAME AS NORMAL WAITS...THINK ABOUT PROBABILITIES THOUGH....AS IN TIMED WAIT MUST FAIL TO GUARANTEE PROGRESS...NORMAL WAIT MAY FAIL...SO NEED NORMAL WAIT TO WORK CORRECTLY IN THE CASE IT SPURIOUSLY FAILS AND IN THE CASE IT DOESN'T... TIMED WAITS MUST EVENMTUALLY RELEASE...
+
/* wake up the other threads */
for (unsigned int i = 0;i < get_num_threads();i++) {
Thread *t = get_thread(int_to_id(i));
continue;
/* Establish hypothetical release sequences */
- rel_heads_list_t release_heads;
- get_release_seq_heads(curr, act, &release_heads);
- for (unsigned int i = 0;i < release_heads.size();i++)
- synchronize(release_heads[i], curr);
- if (release_heads.size() != 0)
+ ClockVector *cv = get_hb_from_write(act);
+ if (curr->get_cv()->merge(cv))
updated = true;
}
}
*/
bool ModelExecution::initialize_curr_action(ModelAction **curr)
{
- ModelAction *newcurr;
-
if ((*curr)->is_rmwc() || (*curr)->is_rmw()) {
- newcurr = process_rmw(*curr);
+ ModelAction *newcurr = process_rmw(*curr);
delete *curr;
*curr = newcurr;
return false;
- }
-
- (*curr)->set_seq_number(get_next_seq_num());
-
- newcurr = node_stack->explore_action(*curr);
- if (newcurr) {
- /* First restore type and order in case of RMW operation */
- if ((*curr)->is_rmwr())
- newcurr->copy_typeandorder(*curr);
-
- ASSERT((*curr)->get_location() == newcurr->get_location());
- newcurr->copy_from_new(*curr);
-
- /* Discard duplicate ModelAction; use action from NodeStack */
- delete *curr;
-
- /* Always compute new clock vector */
- newcurr->create_cv(get_parent_action(newcurr->get_tid()));
-
- *curr = newcurr;
- return false; /* Action was explored previously */
} else {
- newcurr = *curr;
+ ModelAction *newcurr = *curr;
+ newcurr->set_seq_number(get_next_seq_num());
+ node_stack->add_action(newcurr);
/* Always compute new clock vector */
newcurr->create_cv(get_parent_action(newcurr->get_tid()));
* @return True if this read established synchronization
*/
-bool ModelExecution::read_from(ModelAction *act, const ModelAction *rf)
+void ModelExecution::read_from(ModelAction *act, ModelAction *rf)
{
ASSERT(rf);
ASSERT(rf->is_write());
act->set_read_from(rf);
if (act->is_acquire()) {
- rel_heads_list_t release_heads;
- get_release_seq_heads(act, act, &release_heads);
- int num_heads = release_heads.size();
- for (unsigned int i = 0;i < release_heads.size();i++)
- if (!synchronize(release_heads[i], act))
- num_heads--;
- return num_heads > 0;
+ ClockVector *cv = get_hb_from_write(rf);
+ if (cv == NULL)
+ return;
+ act->get_cv()->merge(cv);
}
- return false;
}
/**
if (!second_part_of_rmw && curr->get_type() != NOOP)
add_action_to_lists(curr);
- SnapVector<const ModelAction *> * rf_set = NULL;
+ SnapVector<ModelAction *> * rf_set = NULL;
/* Build may_read_from set for newly-created actions */
if (newly_explored && curr->is_read())
rf_set = build_may_read_from(curr);
/* Last SC fence in the current thread */
ModelAction *last_sc_fence_local = get_last_seq_cst_fence(curr->get_tid(), NULL);
- ModelAction *last_sc_write = NULL;
- if (curr->is_seqcst())
- last_sc_write = get_last_seq_cst_write(curr);
int tid = curr->get_tid();
ModelAction *prev_same_thread = NULL;
/* Iterate over all threads */
- for (i = 0;i < thrd_lists->size();i++, tid = (((unsigned int)(tid+1)) == thrd_lists->size()) ? 0: tid + 1) {
+ for (i = 0;i < thrd_lists->size();i++, tid = (((unsigned int)(tid+1)) == thrd_lists->size()) ? 0 : tid + 1) {
/* Last SC fence in thread tid */
ModelAction *last_sc_fence_thread_local = NULL;
if (i != 0)
//Only need to iterate if either hb has changed for thread in question or SC fence after last operation...
if (prev_same_thread != NULL &&
- (prev_same_thread->get_cv()->getClock(tid) == curr->get_cv()->getClock(tid)) &&
- (last_sc_fence_thread_local == NULL || *last_sc_fence_thread_local < *prev_same_thread)) {
- continue;
+ (prev_same_thread->get_cv()->getClock(tid) == curr->get_cv()->getClock(tid)) &&
+ (last_sc_fence_thread_local == NULL || *last_sc_fence_thread_local < *prev_same_thread)) {
+ continue;
}
-
+
/* Iterate over actions in thread, starting from most recent */
action_list_t *list = &(*thrd_lists)[tid];
action_list_t::reverse_iterator rit;
* before" curr
*/
if (act->happens_before(curr)) {
- if (i==0) {
- if (last_sc_fence_local == NULL ||
- (*last_sc_fence_local < *prev_same_thread)) {
- prev_same_thread = act;
- }
- }
+ if (i==0) {
+ if (last_sc_fence_local == NULL ||
+ (*last_sc_fence_local < *prev_same_thread)) {
+ prev_same_thread = act;
+ }
+ }
if (act->is_write()) {
if (mo_graph->checkReachable(rf, act))
return false;
}
/**
- * Finds the head(s) of the release sequence(s) containing a given ModelAction.
- * The ModelAction under consideration is expected to be taking part in
- * release/acquire synchronization as an object of the "reads from" relation.
- * Note that this can only provide release sequence support for RMW chains
- * which do not read from the future, as those actions cannot be traced until
- * their "promise" is fulfilled. Similarly, we may not even establish the
- * presence of a release sequence with certainty, as some modification order
- * constraints may be decided further in the future. Thus, this function
- * "returns" two pieces of data: a pass-by-reference vector of @a release_heads
- * and a boolean representing certainty.
+ * Computes the clock vector that happens before propagates from this write.
*
* @param rf The action that might be part of a release sequence. Must be a
* write.
- * @param release_heads A pass-by-reference style return parameter. After
- * execution of this function, release_heads will contain the heads of all the
- * relevant release sequences, if any exists with certainty
- * @return true, if the ModelExecution is certain that release_heads is complete;
- * false otherwise
+ * @return ClockVector of happens before relation.
*/
-bool ModelExecution::release_seq_heads(const ModelAction *rf, rel_heads_list_t *release_heads) const
-{
+ClockVector * ModelExecution::get_hb_from_write(ModelAction *rf) const {
+ SnapVector<ModelAction *> * processset = NULL;
for ( ;rf != NULL;rf = rf->get_reads_from()) {
ASSERT(rf->is_write());
+ if (!rf->is_rmw() || (rf->is_acquire() && rf->is_release()) || rf->get_rfcv() != NULL)
+ break;
+ if (processset == NULL)
+ processset = new SnapVector<ModelAction *>();
+ processset->push_back(rf);
+ }
- if (rf->is_release())
- release_heads->push_back(rf);
- else if (rf->get_last_fence_release())
- release_heads->push_back(rf->get_last_fence_release());
- if (!rf->is_rmw())
- break;/* End of RMW chain */
-
- /** @todo Need to be smarter here... In the linux lock
- * example, this will run to the beginning of the program for
- * every acquire. */
- /** @todo The way to be smarter here is to keep going until 1
- * thread has a release preceded by an acquire and you've seen
- * both. */
-
- /* acq_rel RMW is a sufficient stopping condition */
- if (rf->is_acquire() && rf->is_release())
- return true;/* complete */
- };
- ASSERT(rf); // Needs to be real write
-
- if (rf->is_release())
- return true;/* complete */
-
- /* else relaxed write
- * - check for fence-release in the same thread (29.8, stmt. 3)
- * - check modification order for contiguous subsequence
- * -> rf must be same thread as release */
-
- const ModelAction *fence_release = rf->get_last_fence_release();
- /* Synchronize with a fence-release unconditionally; we don't need to
- * find any more "contiguous subsequence..." for it */
- if (fence_release)
- release_heads->push_back(fence_release);
-
- return true; /* complete */
-}
-
-/**
- * An interface for getting the release sequence head(s) with which a
- * given ModelAction must synchronize. This function only returns a non-empty
- * result when it can locate a release sequence head with certainty. Otherwise,
- * it may mark the internal state of the ModelExecution so that it will handle
- * the release sequence at a later time, causing @a acquire to update its
- * synchronization at some later point in execution.
- *
- * @param acquire The 'acquire' action that may synchronize with a release
- * sequence
- * @param read The read action that may read from a release sequence; this may
- * be the same as acquire, or else an earlier action in the same thread (i.e.,
- * when 'acquire' is a fence-acquire)
- * @param release_heads A pass-by-reference return parameter. Will be filled
- * with the head(s) of the release sequence(s), if they exists with certainty.
- * @see ModelExecution::release_seq_heads
- */
-void ModelExecution::get_release_seq_heads(ModelAction *acquire,
- ModelAction *read, rel_heads_list_t *release_heads)
-{
- const ModelAction *rf = read->get_reads_from();
+ int i = (processset == NULL) ? 0 : processset->size();
- release_seq_heads(rf, release_heads);
+ ClockVector * vec = NULL;
+ while(true) {
+ if (rf->get_rfcv() != NULL) {
+ vec = rf->get_rfcv();
+ } else if (rf->is_acquire() && rf->is_release()) {
+ vec = rf->get_cv();
+ } else if (rf->is_release() && !rf->is_rmw()) {
+ vec = rf->get_cv();
+ } else if (rf->is_release()) {
+ //have rmw that is release and doesn't have a rfcv
+ (vec = new ClockVector(vec, NULL))->merge(rf->get_cv());
+ rf->set_rfcv(vec);
+ } else {
+ //operation that isn't release
+ if (rf->get_last_fence_release()) {
+ if (vec == NULL)
+ vec = rf->get_last_fence_release()->get_cv();
+ else
+ (vec=new ClockVector(vec, NULL))->merge(rf->get_last_fence_release()->get_cv());
+ }
+ rf->set_rfcv(vec);
+ }
+ i--;
+ if (i >= 0) {
+ rf = (*processset)[i];
+ } else
+ break;
+ }
+ if (processset != NULL)
+ delete processset;
+ return vec;
}
/**
*/
ClockVector * ModelExecution::get_cv(thread_id_t tid) const
{
- return get_parent_action(tid)->get_cv();
+ ModelAction *firstaction=get_parent_action(tid);
+ return firstaction != NULL ? firstaction->get_cv() : NULL;
}
bool valequals(uint64_t val1, uint64_t val2, int size) {
* @param curr is the current ModelAction that we are exploring; it must be a
* 'read' operation.
*/
-SnapVector<const ModelAction *> * ModelExecution::build_may_read_from(ModelAction *curr)
+SnapVector<ModelAction *> * ModelExecution::build_may_read_from(ModelAction *curr)
{
SnapVector<action_list_t> *thrd_lists = obj_thrd_map.get(curr->get_location());
unsigned int i;
if (curr->is_seqcst())
last_sc_write = get_last_seq_cst_write(curr);
- SnapVector<const ModelAction *> * rf_set = new SnapVector<const ModelAction *>();
+ SnapVector<ModelAction *> * rf_set = new SnapVector<ModelAction *>();
/* Iterate over all threads */
for (i = 0;i < thrd_lists->size();i++) {
action_list_t *list = &(*thrd_lists)[i];
action_list_t::reverse_iterator rit;
for (rit = list->rbegin();rit != list->rend();rit++) {
- const ModelAction *act = *rit;
+ ModelAction *act = *rit;
/* Only consider 'write' actions */
if (!act->is_write()) {
if (act != curr && act->is_read() && act->happens_before(curr)) {
- const ModelAction *tmp = act->get_reads_from();
+ ModelAction *tmp = act->get_reads_from();
if (((unsigned int) id_to_int(tmp->get_tid()))==i)
act = tmp;
else
/* Do not split atomic RMW */
if (curr->is_rmwr())
return get_thread(curr);
- if (curr->is_write()) {
- std::memory_order order = curr->get_mo();
- switch(order) {
- case std::memory_order_relaxed:
- return get_thread(curr);
- case std::memory_order_release:
- return get_thread(curr);
- default:
- return NULL;
- }
- }
-
/* Follow CREATE with the created thread */
/* which is not needed, because model.cc takes care of this */
if (curr->get_type() == THREAD_CREATE)
projects / c11tester.git / blobdiff