From: Brian Norris <banorris@uci.edu>
Date: Sun, 3 Mar 2013 07:37:05 +0000 (-0800)
Subject: mutex: change 'islocked' to hold Thread pointer
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=d3f4056998c5b286c3102be270a863fa88a1bfd5;p=cdsspec-compiler.git

mutex: change 'islocked' to hold Thread pointer

We will need to know which Thread is holding the lock, so just stick it
in the mutex state.
---

diff --git a/include/mutex b/include/mutex
index 482af59..bd65a78 100644
--- a/include/mutex
+++ b/include/mutex
@@ -10,7 +10,7 @@
 
 namespace std {
 	struct mutex_state {
-		bool islocked;
+		void *locked; /* Thread holding the lock */
 		thread_id_t alloc_tid;
 		modelclock_t alloc_clock;
 	};
diff --git a/model.cc b/model.cc
index 7741760..276d18e 100644
--- a/model.cc
+++ b/model.cc
@@ -935,7 +935,7 @@ bool ModelChecker::process_mutex(ModelAction *curr)
 
 	switch (curr->get_type()) {
 	case ATOMIC_TRYLOCK: {
-		bool success = !state->islocked;
+		bool success = !state->locked;
 		curr->set_try_lock(success);
 		if (!success) {
 			get_thread(curr)->set_return_value(0);
@@ -947,7 +947,7 @@ bool ModelChecker::process_mutex(ModelAction *curr)
 	case ATOMIC_LOCK: {
 		if (curr->get_cv()->getClock(state->alloc_tid) <= state->alloc_clock)
 			assert_bug("Lock access before initialization");
-		state->islocked = true;
+		state->locked = get_thread(curr);
 		ModelAction *unlock = get_last_unlock(curr);
 		//synchronize with the previous unlock statement
 		if (unlock != NULL) {
@@ -958,7 +958,7 @@ bool ModelChecker::process_mutex(ModelAction *curr)
 	}
 	case ATOMIC_UNLOCK: {
 		//unlock the lock
-		state->islocked = false;
+		state->locked = NULL;
 		//wake up the other threads
 		action_list_t *waiters = get_safe_ptr_action(lock_waiters_map, curr->get_location());
 		//activate all the waiting threads
@@ -970,7 +970,7 @@ bool ModelChecker::process_mutex(ModelAction *curr)
 	}
 	case ATOMIC_WAIT: {
 		//unlock the lock
-		state->islocked = false;
+		state->locked = NULL;
 		//wake up the other threads
 		action_list_t *waiters = get_safe_ptr_action(lock_waiters_map, (void *) curr->get_value());
 		//activate all the waiting threads
@@ -1402,7 +1402,7 @@ bool ModelChecker::check_action_enabled(ModelAction *curr) {
 	if (curr->is_lock()) {
 		std::mutex *lock = (std::mutex *)curr->get_location();
 		struct std::mutex_state *state = lock->get_state();
-		if (state->islocked) {
+		if (state->locked) {
 			//Stick the action in the appropriate waiting queue
 			get_safe_ptr_action(lock_waiters_map, curr->get_location())->push_back(curr);
 			return false;
diff --git a/mutex.cc b/mutex.cc
index 0bb627d..da3184e 100644
--- a/mutex.cc
+++ b/mutex.cc
@@ -9,7 +9,7 @@ namespace std {
 
 mutex::mutex()
 {
-	state.islocked = false;
+	state.locked = NULL;
 	thread_id_t tid = thread_current()->get_id();
 	state.alloc_tid = tid;
 	state.alloc_clock = model->get_cv(tid)->getClock(tid);