X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=action.cc;h=e88fceef66a8d173e851f4439afd55f1d96564f4;hb=fc32611957cecd106751b62bc4de4aeddc9af56c;hp=6a18ffee8359603d41c475b374817e910287906c;hpb=1ced3dc2f0a7640ec7f724c477ea87affc697ea9;p=model-checker.git

diff --git a/action.cc b/action.cc
index 6a18ffe..e88fcee 100644
--- a/action.cc
+++ b/action.cc
@@ -7,54 +7,134 @@
 #include "action.h"
 #include "clockvector.h"
 #include "common.h"
+#include "threads-model.h"
+#include "nodestack.h"
 
-ModelAction::ModelAction(action_type_t type, memory_order order, void *loc, uint64_t value) :
+#define ACTION_INITIAL_CLOCK 0
+
+/**
+ * @brief Construct a new ModelAction
+ *
+ * @param type The type of action
+ * @param order The memory order of this action. A "don't care" for non-ATOMIC
+ * actions (e.g., THREAD_* or MODEL_* actions).
+ * @param loc The location that this action acts upon
+ * @param value (optional) A value associated with the action (e.g., the value
+ * read or written). Defaults to a given macro constant, for debugging purposes.
+ * @param thread (optional) The Thread in which this action occurred. If NULL
+ * (default), then a Thread is assigned according to the scheduler.
+ */
+ModelAction::ModelAction(action_type_t type, memory_order order, void *loc,
+		uint64_t value, Thread *thread) :
 	type(type),
 	order(order),
 	location(loc),
 	value(value),
 	reads_from(NULL),
-	cv(NULL)
+	last_fence_release(NULL),
+	node(NULL),
+	seq_number(ACTION_INITIAL_CLOCK),
+	cv(NULL),
+	sleep_flag(false)
 {
-	Thread *t = thread_current();
+	/* References to NULL atomic variables can end up here */
+	ASSERT(loc || type == ATOMIC_FENCE || type == MODEL_FIXUP_RELSEQ);
+
+	Thread *t = thread ? thread : thread_current();
 	this->tid = t->get_id();
-	this->seq_number = model->get_next_seq_num();
 }
 
+/** @brief ModelAction destructor */
 ModelAction::~ModelAction()
 {
-	if (cv)
-		delete cv;
+	/**
+	 * We can't free the clock vector:
+	 * Clock vectors are snapshotting state. When we delete model actions,
+	 * they are at the end of the node list and have invalid old clock
+	 * vectors which have already been rolled back to an unallocated state.
+	 */
+
+	/*
+	 if (cv)
+		delete cv; */
+}
+
+void ModelAction::copy_from_new(ModelAction *newaction)
+{
+	seq_number = newaction->seq_number;
+}
+
+void ModelAction::set_seq_number(modelclock_t num)
+{
+	/* ATOMIC_UNINIT actions should never have non-zero clock */
+	ASSERT(!is_uninitialized());
+	ASSERT(seq_number == ACTION_INITIAL_CLOCK);
+	seq_number = num;
+}
+
+bool ModelAction::is_thread_start() const
+{
+	return type == THREAD_START;
 }
 
-void ModelAction::copy_from_new(ModelAction *newaction) {
-	seq_number=newaction->seq_number;
+bool ModelAction::is_relseq_fixup() const
+{
+	return type == MODEL_FIXUP_RELSEQ;
 }
 
-bool ModelAction::is_mutex_op() const {
-	return type == ATOMIC_LOCK || type == ATOMIC_TRYLOCK || type == ATOMIC_UNLOCK;
+bool ModelAction::is_mutex_op() const
+{
+	return type == ATOMIC_LOCK || type == ATOMIC_TRYLOCK || type == ATOMIC_UNLOCK || type == ATOMIC_WAIT || type == ATOMIC_NOTIFY_ONE || type == ATOMIC_NOTIFY_ALL;
 }
 
-bool ModelAction::is_lock() const {
+bool ModelAction::is_lock() const
+{
 	return type == ATOMIC_LOCK;
 }
 
-bool ModelAction::is_unlock() const {
+bool ModelAction::is_wait() const {
+	return type == ATOMIC_WAIT;
+}
+
+bool ModelAction::is_notify() const {
+	return type==ATOMIC_NOTIFY_ONE || type==ATOMIC_NOTIFY_ALL;
+}
+
+bool ModelAction::is_notify_one() const {
+	return type==ATOMIC_NOTIFY_ONE;
+}
+
+bool ModelAction::is_unlock() const
+{
 	return type == ATOMIC_UNLOCK;
 }
 
-bool ModelAction::is_trylock() const {
+bool ModelAction::is_trylock() const
+{
 	return type == ATOMIC_TRYLOCK;
 }
 
-bool ModelAction::is_success_lock() const {
+bool ModelAction::is_success_lock() const
+{
 	return type == ATOMIC_LOCK || (type == ATOMIC_TRYLOCK && value == VALUE_TRYSUCCESS);
 }
 
-bool ModelAction::is_failed_trylock() const {
+bool ModelAction::is_failed_trylock() const
+{
 	return (type == ATOMIC_TRYLOCK && value == VALUE_TRYFAILED);
 }
 
+/** @return True if this operation is performed on a C/C++ atomic variable */
+bool ModelAction::is_atomic_var() const
+{
+	return is_read() || could_be_write();
+}
+
+bool ModelAction::is_uninitialized() const
+{
+	return type == ATOMIC_UNINIT;
+}
+
 bool ModelAction::is_read() const
 {
 	return type == ATOMIC_READ || type == ATOMIC_RMWR || type == ATOMIC_RMW;
@@ -62,7 +142,12 @@ bool ModelAction::is_read() const
 
 bool ModelAction::is_write() const
 {
-	return type == ATOMIC_WRITE || type == ATOMIC_RMW || type == ATOMIC_INIT;
+	return type == ATOMIC_WRITE || type == ATOMIC_RMW || type == ATOMIC_INIT || type == ATOMIC_UNINIT;
+}
+
+bool ModelAction::could_be_write() const
+{
+	return is_write() || is_rmwr();
 }
 
 bool ModelAction::is_rmwr() const
@@ -90,6 +175,11 @@ bool ModelAction::is_initialization() const
 	return type == ATOMIC_INIT;
 }
 
+bool ModelAction::is_relaxed() const
+{
+	return order == std::memory_order_relaxed;
+}
+
 bool ModelAction::is_acquire() const
 {
 	switch (order) {
@@ -121,6 +211,19 @@ bool ModelAction::is_seqcst() const
 
 bool ModelAction::same_var(const ModelAction *act) const
 {
+	if ( act->is_wait() || is_wait() ) {
+		if ( act->is_wait() && is_wait() ) {
+			if ( ((void *)value) == ((void *)act->value) )
+				return true;
+		} else if ( is_wait() ) {
+			if ( ((void *)value) == act->location )
+				return true;
+		} else if ( act->is_wait() ) {
+			if ( location == ((void *)act->value) )
+				return true;
+		}
+	}
+
 	return location == act->location;
 }
 
@@ -130,8 +233,8 @@ bool ModelAction::same_thread(const ModelAction *act) const
 }
 
 void ModelAction::copy_typeandorder(ModelAction * act) {
-	this->type=act->type;
-	this->order=act->order;
+	this->type = act->type;
+	this->order = act->order;
 }
 
 /** This method changes an existing read part of an RMW action into either:
@@ -159,9 +262,9 @@ void ModelAction::process_rmw(ModelAction * act) {
  *  @param act is the action to consider exploring a reordering.
  *  @return tells whether we have to explore a reordering.
  */
-bool ModelAction::is_synchronizing(const ModelAction *act) const
+bool ModelAction::could_synchronize_with(const ModelAction *act) const
 {
-	//Same thread can't be reordered
+	// Same thread can't be reordered
 	if (same_thread(act))
 		return false;
 
@@ -169,15 +272,36 @@ bool ModelAction::is_synchronizing(const ModelAction *act) const
 	if (!same_var(act))
 		return false;
 
-	// Explore interleavings of seqcst writes to guarantee total order
-	// of seq_cst operations that don't commute
-	if (is_write() && is_seqcst() && act->is_write() && act->is_seqcst())
+	// Explore interleavings of seqcst writes/fences to guarantee total
+	// order of seq_cst operations that don't commute
+	if ((could_be_write() || act->could_be_write() || is_fence() || act->is_fence())
+			&& is_seqcst() && act->is_seqcst())
+		return true;
+
+	// Explore synchronizing read/write/fence pairs
+	if (is_acquire() && act->is_release() && (is_read() || is_fence()) &&
+			(act->could_be_write() || act->is_fence()))
+		return true;
+
+	// lock just released...we can grab lock
+	if ((is_lock() ||is_trylock()) && (act->is_unlock()||act->is_wait()))
+		return true;
+
+	// lock just acquired...we can fail to grab lock
+	if (is_trylock() && act->is_success_lock())
 		return true;
 
-	// Explore synchronizing read/write pairs
-	if (is_read() && is_acquire() && act->is_write() && act->is_release())
+	// other thread stalling on lock...we can release lock
+	if (is_unlock() && (act->is_trylock()||act->is_lock()))
 		return true;
-	if (is_write() && is_release() && act->is_read() && act->is_acquire())
+
+	if (is_trylock() && (act->is_unlock()||act->is_wait()))
+		return true;
+
+	if ( is_notify() && act->is_wait() )
+		return true;
+
+	if ( is_wait() && act->is_notify() )
 		return true;
 
 	// Otherwise handle by reads_from relation
@@ -186,18 +310,22 @@ bool ModelAction::is_synchronizing(const ModelAction *act) const
 
 bool ModelAction::is_conflicting_lock(const ModelAction *act) const
 {
-	//Must be different threads to reorder
+	// Must be different threads to reorder
 	if (same_thread(act))
 		return false;
 	
-	//Try to reorder a lock past a successful lock
+	// Try to reorder a lock past a successful lock
 	if (act->is_success_lock())
 		return true;
 	
-	//Try to push a successful trylock past an unlock
+	// Try to push a successful trylock past an unlock
 	if (act->is_unlock() && is_trylock() && value == VALUE_TRYSUCCESS)
 		return true;
 
+	// Try to push a successful trylock past a wait
+	if (act->is_wait() && is_trylock() && value == VALUE_TRYSUCCESS)
+		return true;
+
 	return false;
 }
 
@@ -224,18 +352,23 @@ void ModelAction::set_try_lock(bool obtainedlock) {
 		value=VALUE_TRYFAILED;
 }
 
-/** Update the model action's read_from action */
-void ModelAction::read_from(const ModelAction *act)
+/** @return The Node associated with this ModelAction */
+Node * ModelAction::get_node() const
+{
+	/* UNINIT actions do not have a Node */
+	ASSERT(!is_uninitialized());
+	return node;
+}
+
+/**
+ * Update the model action's read_from action
+ * @param act The action to read from; should be a write
+ */
+void ModelAction::set_read_from(const ModelAction *act)
 {
-	ASSERT(cv);
 	reads_from = act;
-	if (act != NULL && this->is_acquire()) {
-		rel_heads_list_t release_heads;
-		model->get_release_seq_heads(this, &release_heads);
-		for (unsigned int i = 0; i < release_heads.size(); i++)
-			if (!synchronize_with(release_heads[i]))
-				model->set_bad_synchronization();
-	}
+	if (act && act->is_uninitialized())
+		model->assert_bug("May read from uninitialized atomic\n");
 }
 
 /**
@@ -247,14 +380,14 @@ void ModelAction::read_from(const ModelAction *act)
 bool ModelAction::synchronize_with(const ModelAction *act) {
 	if (*this < *act && type != THREAD_JOIN && type != ATOMIC_LOCK)
 		return false;
-	model->check_promises(cv, act->cv);
+	model->check_promises(act->get_tid(), cv, act->cv);
 	cv->merge(act->cv);
 	return true;
 }
 
 bool ModelAction::has_synchronized_with(const ModelAction *act) const
 {
-	return cv->has_synchronized_with(act->cv);
+	return cv->synchronized_since(act);
 }
 
 /**
@@ -268,16 +401,14 @@ bool ModelAction::happens_before(const ModelAction *act) const
 	return act->cv->synchronized_since(this);
 }
 
-/**
- * Print nicely-formatted info about this ModelAction
- *
- * @param print_cv True if we want to print clock vector data. Might be false,
- * for instance, in situations where the clock vector might be invalid
- */
-void ModelAction::print(bool print_cv) const
+/** @brief Print nicely-formatted info about this ModelAction */
+void ModelAction::print() const
 {
 	const char *type_str, *mo_str;
 	switch (this->type) {
+	case MODEL_FIXUP_RELSEQ:
+		type_str = "relseq fixup";
+		break;
 	case THREAD_CREATE:
 		type_str = "thread create";
 		break;
@@ -293,6 +424,9 @@ void ModelAction::print(bool print_cv) const
 	case THREAD_FINISH:
 		type_str = "thread finish";
 		break;
+	case ATOMIC_UNINIT:
+		type_str = "uninitialized";
+		break;
 	case ATOMIC_READ:
 		type_str = "atomic read";
 		break;
@@ -323,6 +457,15 @@ void ModelAction::print(bool print_cv) const
 	case ATOMIC_TRYLOCK:
 		type_str = "trylock";
 		break;
+	case ATOMIC_WAIT:
+		type_str = "wait";
+		break;
+	case ATOMIC_NOTIFY_ONE:
+		type_str = "notify one";
+		break;
+	case ATOMIC_NOTIFY_ALL:
+		type_str = "notify all";
+		break;
 	default:
 		type_str = "unknown type";
 	}
@@ -350,17 +493,35 @@ void ModelAction::print(bool print_cv) const
 		break;
 	}
 
-	printf("(%3d) Thread: %-2d   Action: %-13s   MO: %7s  Loc: %14p  Value: %-12" PRIu64,
+	model_print("(%4d) Thread: %-2d   Action: %-13s   MO: %7s  Loc: %14p   Value: %-#18" PRIx64,
 			seq_number, id_to_int(tid), type_str, mo_str, location, valuetoprint);
 	if (is_read()) {
 		if (reads_from)
-			printf(" Rf: %d", reads_from->get_seq_number());
+			model_print("  Rf: %-3d", reads_from->get_seq_number());
 		else
-			printf(" Rf: ?");
+			model_print("  Rf: ?  ");
 	}
-	if (cv && print_cv) {
-		printf("\t");
+	if (cv) {
+		if (is_read())
+			model_print(" ");
+		else
+			model_print("          ");
 		cv->print();
 	} else
-		printf("\n");
+		model_print("\n");
+}
+
+/** @brief Print nicely-formatted info about this ModelAction */
+unsigned int ModelAction::hash() const
+{
+	unsigned int hash=(unsigned int) this->type;
+	hash^=((unsigned int)this->order)<<3;
+	hash^=seq_number<<5;
+	hash ^= id_to_int(tid) << 6;
+
+	if (is_read()) {
+		if (reads_from)
+			hash^=reads_from->get_seq_number();
+	}
+	return hash;
 }