void AudioNode::deref(RefType refType)
{
// The actually work for deref happens completely within the audio context's graph lock.
// In the case of the audio thread, we must use a tryLock to avoid glitches.
bool hasLock = false;
bool mustReleaseLock = false;
if (context()->isAudioThread()) {
// Real-time audio thread must not contend lock (to avoid glitches).
hasLock = context()->tryLock(mustReleaseLock);
} else {
context()->lock(mustReleaseLock);
hasLock = true;
}
if (hasLock) {
// This is where the real deref work happens.
finishDeref(refType);
if (mustReleaseLock)
context()->unlock();
} else {
// We were unable to get the lock, so put this in a list to finish up later.
ASSERT(context()->isAudioThread());
context()->addDeferredFinishDeref(this, refType);
}
// Once AudioContext::uninitialize() is called there's no more chances for deleteMarkedNodes() to get called, so we call here.
// We can't call in AudioContext::~AudioContext() since it will never be called as long as any AudioNode is alive
// because AudioNodes keep a reference to the context.
if (context()->isAudioThreadFinished())
context()->deleteMarkedNodes();
}
// This method could be called both by the main thread because
// (1) a RefCounted ptr has been deleted or from the audio thread
// because (2) of a disconnect or the deletion of a node that was
// connected to us.
void AudioNode::decrementRefCount(RefType refType) {
bool hasLock;
if (!m_context->canUpdateGraph()) {
m_context->lock();
hasLock = true;
} else {
hasLock = m_context->tryLock();
}
if (hasLock) {
finishDeref(refType);
m_context->unlock();
} else {
assert(m_context->isAudioThread());
m_context->deferFinishDeref(this);
}
}
