// Doubly-linked list of Threads per action for class/classloader pair
// Class circularity support: links in thread before loading superclass
// bootstrapsearchpath support: links in a thread before load_instance_class
// definers: use as queue of define requestors, including owner of
// define token. Appends for debugging of requestor order
void add_seen_thread(Thread* thread, PlaceholderTable::classloadAction action) {
assert_lock_strong(SystemDictionary_lock);
SeenThread* threadEntry = new SeenThread(thread);
SeenThread* seen = actionToQueue(action);
if (seen == NULL) {
set_threadQ(threadEntry, action);
return;
}
SeenThread* next;
while ((next = seen->next()) != NULL) {
seen = next;
}
seen->set_next(threadEntry);
threadEntry->set_prev(seen);
return;
}
// returns true if seenthreadQ is now empty
// Note, caller must ensure probe still exists while holding
// SystemDictionary_lock
// ignores if cleanup has already been done
// if found, deletes SeenThread
bool remove_seen_thread(Thread* thread, PlaceholderTable::classloadAction action) {
assert_lock_strong(SystemDictionary_lock);
SeenThread* threadQ = actionToQueue(action);
SeenThread* seen = threadQ;
SeenThread* prev = NULL;
while (seen) {
if (thread == seen->thread()) {
if (prev) {
prev->set_next(seen->next());
} else {
set_threadQ(seen->next(), action);
}
if (seen->next()) {
seen->next()->set_prev(prev);
}
delete seen;
break;
}
prev = seen;
seen = seen->next();
}
return (actionToQueue(action) == NULL);
}