void AudioDestinationHandler::render(AudioBus* sourceBus, AudioBus* destinationBus, size_t numberOfFrames)
{
// We don't want denormals slowing down any of the audio processing
// since they can very seriously hurt performance.
// This will take care of all AudioNodes because they all process within this scope.
DenormalDisabler denormalDisabler;
// Need to check if the context actually alive. Otherwise the subsequent
// steps will fail. If the context is not alive somehow, return immediately
// and do nothing.
//
// TODO(hongchan): because the context can go away while rendering, so this
// check cannot guarantee the safe execution of the following steps.
ASSERT(context());
if (!context())
return;
context()->deferredTaskHandler().setAudioThreadToCurrentThread();
// If the destination node is not initialized, pass the silence to the final
// audio destination (one step before the FIFO). This check is for the case
// where the destination is in the middle of tearing down process.
if (!isInitialized()) {
destinationBus->zero();
return;
}
// Let the context take care of any business at the start of each render quantum.
context()->handlePreRenderTasks();
// Prepare the local audio input provider for this render quantum.
if (sourceBus)
m_localAudioInputProvider.set(sourceBus);
ASSERT(numberOfInputs() >= 1);
if (numberOfInputs() < 1) {
destinationBus->zero();
return;
}
// This will cause the node(s) connected to us to process, which in turn will pull on their input(s),
// all the way backwards through the rendering graph.
AudioBus* renderedBus = input(0).pull(destinationBus, numberOfFrames);
if (!renderedBus) {
destinationBus->zero();
} else if (renderedBus != destinationBus) {
// in-place processing was not possible - so copy
destinationBus->copyFrom(*renderedBus);
}
// Process nodes which need a little extra help because they are not connected to anything, but still need to process.
context()->deferredTaskHandler().processAutomaticPullNodes(numberOfFrames);
// Let the context take care of any business at the end of each render quantum.
context()->handlePostRenderTasks();
// Advance current sample-frame.
size_t newSampleFrame = m_currentSampleFrame + numberOfFrames;
releaseStore(&m_currentSampleFrame, newSampleFrame);
}
void resumeOthers(bool barrierLocked = false)
{
ThreadState::AttachedThreadStateSet& threads = ThreadState::attachedThreads();
atomicSubtract(&m_unparkedThreadCount, threads.size());
releaseStore(&m_canResume, 1);
// FIXME: Resumed threads will all contend for m_mutex just to unlock it
// later which is a waste of resources.
if (UNLIKELY(barrierLocked)) {
m_resume.broadcast();
} else {
// FIXME: Resumed threads will all contend for
// m_mutex just to unlock it later which is a waste of
// resources.
MutexLocker locker(m_mutex);
m_resume.broadcast();
}
ThreadState* current = ThreadState::current();
for (ThreadState* state : threads) {
if (state == current)
continue;
for (ThreadState::Interruptor* interruptor : state->interruptors())
interruptor->clearInterrupt();
}
threadAttachMutex().unlock();
ASSERT(ThreadState::current()->isAtSafePoint());
}
// Request other attached threads that are not at safe points to park themselves on safepoints.
bool parkOthers()
{
ASSERT(ThreadState::current()->isAtSafePoint());
// Lock threadAttachMutex() to prevent threads from attaching.
threadAttachMutex().lock();
ThreadState::AttachedThreadStateSet& threads = ThreadState::attachedThreads();
MutexLocker locker(m_mutex);
atomicAdd(&m_unparkedThreadCount, threads.size());
releaseStore(&m_canResume, 0);
ThreadState* current = ThreadState::current();
for (ThreadState* state : threads) {
if (state == current)
continue;
for (ThreadState::Interruptor* interruptor : state->interruptors())
interruptor->requestInterrupt();
}
while (acquireLoad(&m_unparkedThreadCount) > 0) {
double expirationTime = currentTime() + lockingTimeout();
if (!m_parked.timedWait(m_mutex, expirationTime)) {
// One of the other threads did not return to a safepoint within the maximum
// time we allow for threads to be parked. Abandon the GC and resume the
// currently parked threads.
resumeOthers(true);
return false;
}
}
return true;
}
bool OfflineAudioDestinationHandler::renderIfNotSuspended(AudioBus* sourceBus, AudioBus* destinationBus, size_t numberOfFrames)
{
// We don't want denormals slowing down any of the audio processing
// since they can very seriously hurt performance.
// This will take care of all AudioNodes because they all process within this scope.
DenormalDisabler denormalDisabler;
context()->deferredTaskHandler().setAudioThread(currentThread());
if (!context()->isDestinationInitialized()) {
destinationBus->zero();
return false;
}
// Take care pre-render tasks at the beginning of each render quantum. Then
// it will stop the rendering loop if the context needs to be suspended
// at the beginning of the next render quantum.
if (context()->handlePreOfflineRenderTasks()) {
suspendOfflineRendering();
return true;
}
// Prepare the local audio input provider for this render quantum.
if (sourceBus)
m_localAudioInputProvider.set(sourceBus);
ASSERT(numberOfInputs() >= 1);
if (numberOfInputs() < 1) {
destinationBus->zero();
return false;
}
// This will cause the node(s) connected to us to process, which in turn will pull on their input(s),
// all the way backwards through the rendering graph.
AudioBus* renderedBus = input(0).pull(destinationBus, numberOfFrames);
if (!renderedBus) {
destinationBus->zero();
} else if (renderedBus != destinationBus) {
// in-place processing was not possible - so copy
destinationBus->copyFrom(*renderedBus);
}
// Process nodes which need a little extra help because they are not connected to anything, but still need to process.
context()->deferredTaskHandler().processAutomaticPullNodes(numberOfFrames);
// Let the context take care of any business at the end of each render quantum.
context()->handlePostOfflineRenderTasks();
// Advance current sample-frame.
size_t newSampleFrame = m_currentSampleFrame + numberOfFrames;
releaseStore(&m_currentSampleFrame, newSampleFrame);
return false;
}
void GCInfoTable::ensureGCInfoIndex(const GCInfo* gcInfo, size_t* gcInfoIndexSlot)
{
ASSERT(gcInfo);
ASSERT(gcInfoIndexSlot);
// Keep a global GCInfoTable lock while allocating a new slot.
DEFINE_THREAD_SAFE_STATIC_LOCAL(Mutex, mutex, new Mutex);
MutexLocker locker(mutex);
// If more than one thread ends up allocating a slot for
// the same GCInfo, have later threads reuse the slot
// allocated by the first.
if (*gcInfoIndexSlot)
return;
int index = ++s_gcInfoIndex;
size_t gcInfoIndex = static_cast<size_t>(index);
RELEASE_ASSERT(gcInfoIndex < GCInfoTable::maxIndex);
if (gcInfoIndex >= s_gcInfoTableSize)
resize();
s_gcInfoTable[gcInfoIndex] = gcInfo;
releaseStore(reinterpret_cast<int*>(gcInfoIndexSlot), index);
}
void DeferredTaskHandler::setAudioThreadToCurrentThread() {
DCHECK(!isMainThread());
ThreadIdentifier thread = currentThread();
releaseStore(&m_audioThread, thread);
}
void CryptoResultImpl::ResultCancel::cancel()
{
releaseStore(&m_cancelled, 1);
}