/**
* We're leaving the current thread. So we need to deactivate
* this.
*/
void InterpreterInstance::exitCurrentThread()
{
// find the current activity and deactivate it, and
// release the kernel lock.
RexxActivity *activity = findActivity();
activity->exitCurrentThread();
}
RexxActivity *ActivityManager::findActivity()
/******************************************************************************/
/* Function: Locate the activity associated with a thread */
/******************************************************************************/
{
return findActivity(SysActivity::queryThreadID());
}
/**
* Attach a thread to an interpreter instance.
*
* @return The attached activity.
*/
RexxActivity *InterpreterInstance::attachThread()
{
// first check for an existing activity
RexxActivity *activity = findActivity();
// do we have this? we can just return it
if (activity != OREF_NULL)
{
// make sure we mark this as attached...we might be nested and don't want to
// clean this up until we complete
activity->nestAttach();
return activity;
}
// we need to get a new activity set up for this particular thread
activity = ActivityManager::attachThread();
// resource lock must come AFTER we attach the thread, otherwise
// we can create a deadlock situation when we attempt to get the kernel
// lock
ResourceSection lock("InterpreterInstance::attachThread", 0);
// add this to the activity lists
allActivities->append((RexxObject *)activity);
// associate the thread with this instance
activity->setupAttachedActivity(this);
return activity;
}
/**
* Attach an activity to an interpreter instance
*
* @param instance The interpreter instance involved.
*
* @return Either an existing activity, or a new activity created for
* this thread.
*/
RexxActivity *ActivityManager::attachThread()
{
// it's possible we already have an activity active for this thread. That
// most likely occurs in nested RexxStart() calls.
RexxActivity *oldActivity = findActivity();
// we have an activity created for this thread already. The interpreter instance
// should already have handled the case of an attach for an already attached thread.
// so we're going to have a new activity to create, and potentially an existing one to
// suspend
// we need to lock the kernel to have access to the memory manager to
// create this activity.
lockKernel();
RexxActivity *activityObject = createCurrentActivity();
// Do we have a nested interpreter call occurring on the same thread? We need to
// mark the old activity as suspended, and chain this to the new activity.
if (oldActivity != OREF_NULL)
{
oldActivity->setSuspended(true);
// this pushes this down the stack.
activityObject->setNestedActivity(oldActivity);
}
unlockKernel(); /* release kernel semaphore */
// now we need to have this activity become the kernel owner.
activityObject->requestAccess();
// this will help ensure that the code after the request access call
// is only executed after access acquired.
sentinel = true;
// belt-and-braces. Make sure the current activity is explicitly set to
// this activity before leaving.
currentActivity = activityObject;
return activityObject;
}
/**
* Flip on external trace for a thread.
*
* @param thread_id The target thread id.
* @param on_or_off The trace setting.
*
* @return true if this worked, false otherwise.
*/
bool ActivityManager::setActivityTrace(thread_id_t thread_id, bool on_or_off )
{
ResourceSection lock;
// locate the activity associated with this thread_id. If not found, return
// a failure.
Activity *activity = findActivity(thread_id);
if (activity != OREF_NULL)
{
return activity->setTrace(on_or_off);
}
return false; // this was a failure
}
/**
* Raise a halt condition on an activity.
*
* @param thread_id The target thread identifier.
* @param description
* The description of the halt.
*
* @return Returns the halt result. Returns false if a halt
* condition is already pending or the target activity
* is not found.
*/
bool ActivityManager::haltActivity(thread_id_t thread_id, RexxString * description )
{
ResourceSection lock;
// locate the activity associated with this thread_id. If not found, return
// a failure.
Activity *activity = findActivity(thread_id);
if (activity != OREF_NULL)
{
return activity->halt(description);
}
return false; // this was a failure
}
/**
* Get an already existing activity for the current thread and
* give it kernel access before returning. This will fail if
* the thread has not been properly attached.
*
* @return The activity for this thread.
*/
RexxActivity *ActivityManager::getActivity()
{
// it's possible we already have an activity active for this thread. That
// most likely occurs in nested RexxStart() calls.
RexxActivity *activityObject = findActivity();
if (activityObject == OREF_NULL) /* Nope, 1st time through here. */
{
// this is an error....not sure how to handle this.
return OREF_NULL;
}
// go acquire the kernel lock and take care of nesting
activityObject->enterCurrentThread();
return activityObject; // Return the activity for thread
}
/**
* Get an already existing activity for the current thread and
* give it kernel access before returning. This will fail if
* the thread has not been properly attached.
*
* @return The activity for this thread.
*/
Activity *ActivityManager::getActivity()
{
// it's possible we already have an activity active for this thread. That
// most likely occurs in nested RexxStart() calls.
Activity *activityObject = findActivity();
// we generally should have something. Somehow we have an improperly
// attached thread. Just return a failure indicator.
if (activityObject == OREF_NULL)
{
return OREF_NULL;
}
// go acquire the kernel lock and take care of nesting
activityObject->enterCurrentThread();
return activityObject; // Return the activity for thread
}
bool ActivityManager::setActivityTrace(
thread_id_t thread_id, /* target thread id */
bool on_or_off ) /* trace on/off flag */
/******************************************************************************/
/* Function: Flip on a bit in a target activities top activation */
/******************************************************************************/
{
ResourceSection lock("ActivityManager::setActivityTrace", 0);
// locate the activity associated with this thread_id. If not found, return
// a failure.
RexxActivity *activity = findActivity(thread_id);
if (activity != OREF_NULL)
{
return activity->setTrace(on_or_off);
}
return false; // this was a failure
}
bool ActivityManager::haltActivity(
thread_id_t thread_id, /* target thread id */
RexxString * description ) /* description to use */
/******************************************************************************/
/* Function: Flip on a bit in a target activities top activation */
/******************************************************************************/
{
ResourceSection lock("ActivityManager::haltActivity", 0);
// locate the activity associated with this thread_id. If not found, return
// a failure.
RexxActivity *activity = findActivity(thread_id);
if (activity != OREF_NULL)
{
return activity->halt(description);
}
return false; // this was a failure
}
/**
* Get a root activity for a new interpreter instance.
*
* @return The newly created activity.
*/
Activity *ActivityManager::getRootActivity()
{
// it's possible we already have an activity active for this thread. That
// most likely occurs in nested RexxStart() calls. Get that activity first,
// and if we have one, we'll need to push this down.
Activity *oldActivity = findActivity();
// we need to lock the kernel to have access to the memory manager to
// create this activity.
lockKernel();
// get a new activity object
Activity *activityObject = createCurrentActivity();
unlockKernel();
// mark this as the root activity for an interpreter instance. Some operations
// are only permitted from the root threads.
activityObject->setInterpreterRoot();
// Do we have a nested interpreter call occurring on the same thread? We need to
// mark the old activity as suspended, and chain this to the new activity.
if (oldActivity != OREF_NULL)
{
oldActivity->setSuspended(true);
// this pushes this down the stack.
activityObject->setNestedActivity(oldActivity);
}
// now we need to have this activity become the kernel owner.
activityObject->requestAccess();
// this will help ensure that the code after the request access call
// is only executed after access acquired.
sentinel = true;
activityObject->activate(); // let the activity know it's in use, potentially nested
// belt-and-braces. Make sure the current activity is explicitly set to
// this activity before leaving.
currentActivity = activityObject;
return activityObject;
}
/**
* Attempt to shutdown the interpreter instance. This can only be done
* from the root activity.
*
* @return true if shutdown has been initiated, false otherwise.
*/
bool InterpreterInstance::terminate()
{
// if our current activity is not the root one, we can't do that
RexxActivity *current = findActivity();
// we also can't be doing active work on the root thread
if (current != rootActivity || rootActivity->isActive())
{
return false;
}
terminated = false;
// turn on the global termination in process flag
terminating = true;
{
ResourceSection lock("InterpreterInstance::terminate", 0);
// remove the current activity from the list so we don't clean everything
// up. We need to
allActivities->removeItem((RexxObject *)current);
// go remove all of the activities that are not doing work for this instance
removeInactiveActivities();
// no activities left? We can leave now
terminated = allActivities->items() == 0;
// we need to restore the rootActivity to the list for potentially running uninits
allActivities->append((RexxObject *)current);
}
// if there are active threads still running, we need to wait until
// they all finish
if (!terminated)
{
terminationSem.wait("InterpreterInstance::terminate", 0);
}
// if everything has terminated, then make sure we run the uninits before shutting down.
// This activity is currently the current activity. We're going to run the
// uninits on this one, so reactivate it until we're done running
enterOnCurrentThread();
// release any global references we've been holding.
globalReferences->empty();
// before we update of the data structures, make sure we process any
// pending uninit activity.
memoryObject.verboseMessage("Calling runUninits through collectAndUninit from InterpreterInstance::terminate\n");
memoryObject.collectAndUninit(Interpreter::lastInstance());
// do system specific termination of an instance
sysInstance.terminate();
// ok, deactivate this again...this will return the activity because the terminating
// flag is on.
exitCurrentThread();
terminationSem.close();
// make sure the root activity is removed by the ActivityManager;
ActivityManager::returnRootActivity(current);
// tell the main interpreter controller we're gone.
Interpreter::terminateInterpreterInstance(this);
return true;
}
/**
* Find an activity for the current thread that's associated
* with this activity.
*
* @return The target activity.
*/
RexxActivity *InterpreterInstance::findActivity()
{
return findActivity(SysActivity::queryThreadID());
}
/**
* Detach a thread from this interpreter instance.
*
* @return true if this worked ok.
*/
bool InterpreterInstance::detachThread()
{
// first check for an existing activity
return detachThread(findActivity());
}
/**
* Locate the activity associated with the current thread
*
* @return The Activity for this thread, if it exists.
*/
Activity *ActivityManager::findActivity()
{
return findActivity(SysActivity::queryThreadID());
}
