protected final void releaseAllLocks(Component host_) {
String old_ = state;
setState(State_UNLOCKING);
for (LockPack p_ = (LockPack) host_.locks; p_ != null; p_ = p_.next)
if (p_.holder == this) {
// unlock(host_, p_.target, true);
// below is copied from unlock()
synchronized (p_) {
p_.holder = null;
p_.counter = -1;
// p_.counter is not zero, see Note 1 above
if (p_.lockReqCount == 0) {
continue;
}
p_.lockReqCount--;
synchronized (aruntime) {
if (aruntime.getWorkforce()) {
p_.notify(); // dont know who's going to wake up
aruntime.nthreadsWaiting--;
} else aruntime.newTask(Task.createNotify(p_), this);
}
}
}
setState(old_);
}
// Notifies all the threads waiting on the object.
protected final void notifyAll(Component host_, Object o_) {
if (o_ == null) return;
String old_ = state;
setState(State_NOTIFYING);
// sleepOn = o_;
LockPack p_ = lookforLock(host_, o_);
synchronized (o_) {
// setState(State_NOTIFYING2);
// sleepOn = null;
if (p_.waitCount == 0) return;
// runtime._notifyMany(o_, p_.waitCount, this);
synchronized (aruntime) {
if (aruntime.getWorkforce(p_.waitCount)) {
o_.notifyAll(); // dont know who's going to wake up
aruntime.nthreadsWaiting -= p_.waitCount;
} else {
int remainingWorkforce_ = aruntime.getRemainingWorkforce();
// notify "remainingWorkforce_" threads
for (int i = 0; i < remainingWorkforce_; i++) o_.notify();
aruntime.nthreadsWaiting -= remainingWorkforce_;
for (int i = p_.waitCount - remainingWorkforce_; i > 0; i--)
aruntime.newTask(Task.createNotify(o_), this);
}
}
p_.waitCount = 0;
}
setState(old_);
}
protected void unlock(Component host_, Object o_, boolean release_) {
LockPack p_ = lookforLock(host_, o_);
String old_ = state;
setState(State_UNLOCKING);
synchronized (p_) {
if (release_ || --p_.counter < 0) p_.counter = 0;
if (p_.counter == 0) {
if (p_.lockReqCount == 0) {
p_.holder = null;
return;
}
// Note 1:
// what if another thread grabs the lock before
// the one being notified below?
// p_.counter is not zero so other threads cannot just grab it
p_.lockReqCount--;
p_.counter = -1;
p_.holder = null;
synchronized (aruntime) {
if (aruntime.getWorkforce()) {
p_.notify(); // dont know who's going to wake up
aruntime.nthreadsWaiting--;
} else {
aruntime.newTask(Task.createNotify(p_), this);
}
}
// ---
}
}
setState(old_);
}
// Make thread wait on the object until being notified by another thread.
protected final void wait(Component host_, Object o_) {
// if (nextTask != null) _semanticsError("wait(Object)");
// looking for LockPack in host
LockPack p_ = lookforLock(host_, o_);
String old_ = state;
setState(State_WAITING);
synchronized (o_) {
// Records the status if the thread holds the lock.
if (waitPack == null) waitPack = new WaitPack();
waitPack.target = p_.target;
if (p_.holder == this) {
waitPack.counter = p_.counter;
// unlock(host_, o_, true/* release all grabs */);
// below is copied from unlock()
synchronized (p_) {
p_.holder = null;
if (p_.lockReqCount == 0) p_.counter = 0;
else {
p_.counter = -1;
// p_.counter is not zero, see Note 1 above
p_.lockReqCount--;
synchronized (aruntime) {
if (aruntime.getWorkforce()) {
p_.notify(); // dont know who's going to wake up
aruntime.nthreadsWaiting--;
} else aruntime.newTask(Task.createNotify(p_), this);
}
}
}
}
p_.waitCount++;
// waited to be notified
_sleepOn(o_, State_WAITING, null);
if (isOrphan()) throw new WorkerThreadInterruptedException("Orphan thread");
// _awakened();
// re-grabbing the lock if necessary.
if (waitPack.counter > 0) {
synchronized (p_) {
if (p_.holder != null) lock(host_, p_.target);
else {
p_.holder = this;
p_.counter = waitPack.counter;
}
}
}
}
if (p_ != null) {
waitPack.counter = 0;
waitPack.target = null;
}
}
/**
* Returns the thread that is holding the lock of the target object. The returned thread may be an
* orphan thread from previous run. final WorkerThread getHolder(Object o_) { Component host_ =
* getHost(); if (host_ == null) return null; LockPack p_ = lookforLock(host_, o_); return p_ ==
* null? null: p_.holder; }
*/
protected void yieldToRuntime() {
synchronized (this) { // avoid racing with runtime.stop()
if (aruntime.isSuspend())
// go into sleep if runtime is suspended
__sleepOn(this, State_PREACTIVE, state);
else if (runtime.resetting) throw new WorkerThreadInterruptedException();
aruntime.newTask(Task.createNotify(this), this);
_sleepOn(this, State_YIELD, null);
}
}
void _sleepOn(Object sleepOn_, String prestate_, String poststate_) {
if (poststate_ == null) poststate_ = state;
sleepOn = sleepOn_;
synchronized (sleepOn) {
if (nextTask != null) _semanticsError("wait()");
aruntime.threadBecomesWaiting(this);
__sleepOn(sleepOn_, prestate_, State_AWAKENING);
// runtime.threadAwakeFromWaiting(this);
if (aruntime.debug && aruntime.isDebugEnabledAt(aruntime.Debug_Q))
aruntime.println(
aruntime.Debug_Q, this, "awaked from indefinite sleep: " + _currentContext());
}
setState(poststate_);
}
protected void changeCurrentContext(Port port_, Object data_, String state_) {
// mainContext = new Task(port_, data_, mainContext.type, 0.0);
if (currentContext == mainContext || currentContext == null)
currentContext = new TaskReceive(port_, data_);
else {
currentContext.data = data_;
currentContext.port = port_;
}
if (state_ != null) state = state_;
;
if (aruntime.debug && aruntime.isDebugEnabledAt(ARuntime.Debug_THREAD))
aruntime.println(
ARuntime.Debug_THREAD,
this,
"currentContext ---> " + "state:" + state + "," + _currentContext());
}
protected final void setState(String new_) {
if (state == new_) return;
if (aruntime.debug) aruntime.threadStateChange(this, state, new_);
// if (stateQ.isFull()) stateQ.dequeue(); // temporary
// stateQ.enqueue(state); // temporary
state = new_;
}
// Notifies the first thread waiting on the object.
protected final void notify(Component host_, Object o_) {
if (o_ == null) return;
String old_ = state;
setState(State_NOTIFYING);
// sleepOn = o_;
LockPack p_ = lookforLock(host_, o_);
synchronized (o_) {
// setState(State_NOTIFYING2);
// sleepOn = null;
if (p_.waitCount == 0) return;
p_.waitCount--;
synchronized (aruntime) {
if (aruntime.getWorkforce()) {
o_.notify(); // dont know who's going to wake up
aruntime.nthreadsWaiting--;
} else {
aruntime.newTask(Task.createNotify(o_), this);
}
}
}
setState(old_);
}
void _sleepUntil(double time_, String poststate_) {
if (poststate_ == null) poststate_ = state;
setWakeupTime(time_);
// set the following two lines before calling
// runtime.threadRequestsWaiting() to avoid racing
// (see codes below)
if (sleepOn == null) sleepOn = this;
// for wait(Object, double), sleepOn is preset
synchronized (sleepOn) {
if (nextTask != null) _semanticsError("sleep()");
if (aruntime.threadRequestsSleeping(this, time_)) {
__sleepOn(sleepOn, State_SLEEPING, State_AWAKENING);
// runtime.threadAwakeFromSleeping(this);
if (aruntime.debug && aruntime.isDebugEnabledAt(aruntime.Debug_Q))
aruntime.println(
aruntime.Debug_Q, this, "awaked from finite sleep, " + _currentContext());
}
setWakeupTime(Double.NaN);
}
setState(poststate_);
}
/** Delay the starting until the time specified later(second). */
public void start() {
// if (port != null) System.out.println(this + " starts: " + data);
// runtime.startRegister(this);
if (aruntime.isSuspend()) return;
if (isAlive()) {
// __wakeUp();
synchronized (this) {
lastsleepon = this;
lastwakeupthread = Thread.currentThread();
try {
this.notify();
} catch (Exception e_) {
drcl.Debug.error(this, "start()| " + e_, false);
}
}
} else {
// the thread is newly created
setState(State_INACTIVE);
super.start();
}
}
/** Let go of the thread from sleep in idle. */
public void kill() {
if (isAlive()) interrupt();
else aruntime.remove(this);
}
/** Standard Thread.run(). */
public /*final*/ void run() {
if (Thread.currentThread() != this) {
throw new WorkerThreadException(
"not run() by the owning thread. Current thread:"
+ Thread.currentThread()
+ "---owning thread:"
+ this);
}
try {
if (aruntime.debug && aruntime.isDebugEnabledAt(ARuntime.Debug_THREAD))
aruntime.println(ARuntime.Debug_THREAD, this, "THREAD STARTS");
for (; ; ) {
// Note:
// getTask() and recycle() must happen atomically because
// during the time after this thread cannot get more tasks
// from runtime.getTask() and before it goes to recycle() to
// return workforce, another thread may produce a new task in
// the ready queue (without this thread knowing it) and that
// thread goes to the waiting state. Due to this racing,
// the simulation could be stalled as no thread is actively
// running to execute the new task in the ready queue.
synchronized (aruntime) {
if (mainContext == null || mainContext == DUMMY_CONTEXT) {
// grab a task from worker pool
nextTask = GETTING_TASK;
// XXX: temporary for debug
nextTask = aruntime.getTask(mainContext == null);
if (nextTask != null) {
// so null wont override DUMMY_CONTEXT
mainContext = nextTask;
nextTask = null;
} else {
setState(State_RECYCLING);
sleepOn = this;
aruntime.recycle(this);
// return workforce in recycle()
}
}
}
if (state == State_RECYCLING) {
setState(State_INACTIVE);
// BOOKMARK1:
// At this point, other threads may assign a new task
// to this thread and start this thread, so check if
// mainContext is being assigned within
// the following synchronized claus
synchronized (this) {
if (mainContext == DUMMY_CONTEXT) mainContext = null;
if (mainContext == null) {
__sleepOn(this, State_INACTIVE, State_INACTIVE);
continue;
} else sleepOn = null;
}
}
if (runtime.resetting) {
throw new WorkerThreadInterruptedException();
} else if (aruntime.isSuspend()) {
// go into sleep if runtime is suspended
synchronized (this) {
__sleepOn(this, State_PREACTIVE, State_ACTIVE);
}
}
if (mainContext.threadGroup != null) {
if (mainContext instanceof TaskNotify) {
// mainContext is TaskNotify:
// the object to be notified on is in "data"
synchronized (mainContext.data) {
if (aruntime.debug && aruntime.isDebugEnabledAt(ARuntime.Debug_THREAD))
aruntime.println(
ARuntime.Debug_THREAD,
this,
"EXECUTING notify:" + mainContext.data + "," + System.currentTimeMillis());
mainContext.data.notify();
aruntime.nthreadsWaiting--;
}
mainContext = null;
// workforce transfered to the waked up thread
continue;
} else if (getThreadGroup() != mainContext.threadGroup) {
aruntime.immediatelyStart(mainContext);
mainContext = null;
// workforce transfered to new thread
continue;
}
}
if (aruntime.debug && aruntime.isDebugEnabledAt(ARuntime.Debug_THREAD))
aruntime.println(ARuntime.Debug_THREAD, this, "EXECUTING:" + mainContext);
setState(State_ACTIVE);
// runtime.runCheck(this);
String method_ = "process()";
currentContext = mainContext;
returnPort = currentContext.returnPort;
// from server port, new context
try {
mainContext.execute(this);
} catch (NullPointerException e_) {
if (runtime == null) return;
e_.printStackTrace();
drcl.Debug.error(info());
} catch (Exception e_) {
e_.printStackTrace();
drcl.Debug.error(info());
} catch (SendReceiveException e_) {
e_.printStackTrace();
drcl.Debug.error(info());
}
currentContext.port = null;
currentContext.data = null;
finishing();
mainContext = DUMMY_CONTEXT;
// to maintain the ownership of workforce
if (!RECYCLING) {
aruntime.remove(this);
break;
}
if (nextTask != null) {
// error checking
if (mainContext != null && mainContext != DUMMY_CONTEXT)
drcl.Debug.systemFatalError("task assigned to occupied thread:" + this);
mainContext = nextTask;
nextTask = null;
}
} // for(;;)
drcl.Debug.systemFatalError("Unexpected finish at " + this);
} catch (WorkerThreadInterruptedException e_) {
// if (!runtime.resetting) {
// e_.printStackTrace();
// drcl.Debug.systemFatalError(
// "AWorkerThread terminates abnormally, " + this
// + "\nManager: " + runtime.diag());
// }
// Will releaseAllLocks()/cancelAllWaits() clean up the lock
// structure in components?
// Not if the thread comes across multiple components...
if (mainContext != null && mainContext.port != null) releaseAllLocks(mainContext.port.host);
aruntime.remove(this);
} catch (NullPointerException e_) {
if (runtime != null) {
e_.printStackTrace();
drcl.Debug.error(info());
}
}
runtime = null; // become an orphan
aruntime = null;
}
