Add WebThread in AudioDestination to support AudioWorkletThread

third_party/WebKit/Source/platform/audio/PushPullFIFO.cpp

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "platform/audio/PushPullFIFO.h"
 
 #include <memory>
 #include "platform/audio/AudioUtilities.h"
 #include "wtf/PtrUtil.h"
 
@@ skipping 16 matching lines @@
       m_underflowCount(0) {
   CHECK_LE(m_fifoLength, kMaxFIFOLength);
   m_fifoBus = AudioBus::create(numberOfChannels, m_fifoLength);
 }
 
 PushPullFIFO::~PushPullFIFO() {}
 
 // Push the data from |inputBus| to FIFO. The size of push is determined by
 // the length of |inputBus|.
 void PushPullFIFO::push(const AudioBus* inputBus) {
+  MutexLocker lock(m_threadMutex);
+
   CHECK(inputBus);
   CHECK_EQ(inputBus->length(), AudioUtilities::kRenderQuantumFrames);
   SECURITY_CHECK(inputBus->length() <= m_fifoLength);
   SECURITY_CHECK(m_indexWrite < m_fifoLength);
 
   const size_t inputBusLength = inputBus->length();
   const size_t remainder = m_fifoLength - m_indexWrite;
 
   for (unsigned i = 0; i < m_fifoBus->numberOfChannels(); ++i) {
     float* fifoBusChannel = m_fifoBus->channel(i)->mutableData();
@@ skipping 29 matching lines @@
 
   // Update the number of frames available in FIFO.
   m_framesAvailable =
       std::min(m_framesAvailable + inputBusLength, m_fifoLength);
   DCHECK_EQ((m_indexRead + m_framesAvailable) % m_fifoLength, m_indexWrite);
 }
 
 // Pull the data out of FIFO to |outputBus|. If remaining frame in the FIFO
 // is less than the frames to pull, provides remaining frame plus the silence.
 void PushPullFIFO::pull(AudioBus* outputBus, size_t framesRequested) {
+  MutexLocker lock(m_threadMutex);
+
 #if OS(ANDROID)
   if (!outputBus) {
     // Log when outputBus or FIFO object is invalid. (crbug.com/692423)
     LOG(WARNING) << "[WebAudio/PushPullFIFO::pull <" << static_cast<void*>(this)
                  << ">] |outputBus| is invalid.";
     // Silently return to avoid crash.
     return;
   }
 
   // The following checks are in place to catch the inexplicable crash.
@@ skipping 61 matching lines @@
                    << ", requestedFrames=" << framesRequested
                    << ", fifoLength=" << m_fifoLength << ")";
     }
   }
 
   // Update the number of frames in FIFO.
   m_framesAvailable -= framesToFill;
   DCHECK_EQ((m_indexRead + m_framesAvailable) % m_fifoLength, m_indexWrite);
 }
 
+size_t PushPullFIFO::framesAvailable() const {
+  MutexLocker lock(m_threadMutex);
+  return m_framesAvailable;

[o1ka, 2017/03/30 13:17:05]

This is correct but unfortunate to have a lock here, as we discussed - we want
to minimize locking. That's why I propose to refactor the code and to get rid of
this method.

[hongchan, 2017/03/30 18:36:00]

Acknowledged.

+}
+
+AudioBus* PushPullFIFO::getFIFOBusForTest() const {
+  MutexLocker lock(m_threadMutex);
+  return m_fifoBus.get();
+}
+
 const PushPullFIFOStateForTest PushPullFIFO::getStateForTest() const {
+  MutexLocker lock(m_threadMutex);
   return {length(),     numberOfChannels(), framesAvailable(), m_indexRead,
           m_indexWrite, m_overflowCount,    m_underflowCount};
 }
 
 }  // namespace blink