Add WebThread in AudioDestination to support AudioWorkletThread

third_party/WebKit/Source/platform/audio/PushPullFIFOSmokeTest.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 <vector>
+#include "platform/CrossThreadFunctional.h"
+#include "platform/WaitableEvent.h"
+#include "platform/WebTaskRunner.h"
+#include "platform/audio/AudioUtilities.h"
+#include "platform/testing/UnitTestHelpers.h"
+#include "platform/wtf/Functional.h"
+#include "platform/wtf/PtrUtil.h"
+#include "public/platform/Platform.h"
+#include "public/platform/WebThread.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace blink {
+
+namespace {
+
+// To forcibly stop the message loop.
+// TODO(hongchan): move this hack into Test class.
+void FinishTest() {
+  LOG(INFO) << "FinishTest";
+  testing::ExitRunLoop();
+}
+
+// To wait for spawned threads to finish their tasks.
+// TODO(hongchan): move this hack into Test class.

[o1ka, 2017/04/25 08:23:22]

Fix TODOs?

[hongchan, 2017/04/25 20:36:42]

It seems to be impossible at the moment. Other Blink unit tests running on
multi-thread use the same hack like this. (registering start/stop functions in
global scope)

https://cs.chromium.org/chromium/src/third_party/WebKit/Source/web/tests/Virt...

I spent quite a while to fix this but couldn't find another way.

+void HoldTestForDuration(double duration_ms) {
+  LOG(INFO) << "HoldTestForDuration";
+  Platform::Current()->CurrentThread()->GetWebTaskRunner()->PostDelayedTask(
+      BLINK_FROM_HERE,
+      WTF::Bind(&FinishTest),
+      duration_ms);
+  testing::EnterRunLoop();
+}
+
+// Base FIFOClient with an extra thread for looping and jitter control. The
+// child class must define a specific task to run on the thread.
+class FIFOClient {
+ public:
+  FIFOClient(PushPullFIFO* fifo, size_t jitter_range_ms)
+      : fifo_(fifo),
+        jitter_range_ms_(jitter_range_ms),
+        client_thread_(WTF::WrapUnique(
+            Platform::Current()->CreateThread("client thread"))) {}
+
+  void Start(double duration_ms, double interval_ms) {
+    duration_ms_ = duration_ms;
+    interval_ms_ = interval_ms;
+    client_thread_->GetWebTaskRunner()->PostTask(
+        BLINK_FROM_HERE,
+        CrossThreadBind(&FIFOClient::RunTaskOnOwnThread,
+                        CrossThreadUnretained(this)));
+  }
+
+  virtual void RunTask() = 0;
+  virtual void Stop() = 0;
+
+ protected:
+  RefPtr<AudioBus> bus_;
+  PushPullFIFO* fifo_;
+  double elapsed_ms_ = 0;
+  int counter_ = 0;

[o1ka, 2017/04/25 08:23:22]

Could you refactor the code to make all the members private?

[hongchan, 2017/04/25 20:36:42]

Done.

+
+ private:
+  void RunTaskOnOwnThread() {
+    double interval_with_jitter = interval_ms_
+        + (static_cast<double>(std::rand()) / RAND_MAX) * jitter_range_ms_;
+    elapsed_ms_ += interval_with_jitter;
+    ++counter_;
+    RunTask();
+    if (elapsed_ms_ < duration_ms_) {
+      client_thread_->GetWebTaskRunner()->PostDelayedTask(
+              BLINK_FROM_HERE,
+              CrossThreadBind(&FIFOClient::RunTaskOnOwnThread,
+                              CrossThreadUnretained(this)),
+              interval_with_jitter);
+    } else {
+      Stop();
+    }
+  }
+
+  double duration_ms_;
+  double interval_ms_;
+  double jitter_range_ms_;

[o1ka, 2017/04/25 08:23:22]

Add comments for these members?

[hongchan, 2017/04/25 20:36:42]

Done.

+  std::unique_ptr<WebThread> client_thread_;
+};
+
+// FIFO-pulling client (consumer). This mimics the audio device thread.
+class PullClient : public FIFOClient {
+ public:
+  PullClient(PushPullFIFO* fifo, size_t frames_to_pull, double jitter_range_ms)
+      : FIFOClient(fifo, jitter_range_ms),
+        frames_to_pull_(frames_to_pull) {
+    bus_ = AudioBus::Create(fifo_->NumberOfChannels(), frames_to_pull_);
+  }
+
+  void RunTask() override {
+    fifo_->Pull(bus_.Get(), frames_to_pull_);
+  }
+
+  void Stop() override {
+    LOG(INFO) << "PullClient::Stop (" << counter_ << "calls)";
+  }
+
+ private:
+  size_t frames_to_pull_;
+};
+
+// FIFO-pushing client (producer). This mimics the WebAudio rendering thread.
+class PushClient : public FIFOClient {
+ public:
+  PushClient(PushPullFIFO* fifo, size_t frames_to_push, double jitter_range_ms)
+      : FIFOClient(fifo, jitter_range_ms) {
+    bus_ = AudioBus::Create(fifo_->NumberOfChannels(), frames_to_push);
+  }
+
+  void RunTask() override {
+    fifo_->Push(bus_.Get());
+  }
+
+  void Stop() override {
+    LOG(INFO) << "PushClient::Stop (" << counter_ << "calls)";
+  }
+};
+
+struct FIFOSmokeTestParam {
+  const double sample_rate;
+  const unsigned number_of_channels;
+  const size_t fifo_length;
+  const double test_duration_ms;
+  // Buffer size for pulling. Equivalent of |callback_buffer_size|.
+  const size_t pull_buffer_size;
+  // Jitter added to the regular pulling interval, where j is
+  // 0 < j < jitter_range_ms.
+  const double pull_jitter_range_ms;
+  // Buffer size for pushing. Equivalent of WebAudio render quantum.
+  const size_t push_buffer_size;
+  // Jitter range for the pushing interval.
+  const double push_jitter_range_ms;
+};
+
+class PushPullFIFOSmokeTest
+    : public ::testing::TestWithParam<FIFOSmokeTestParam> {};
+
+TEST_P(PushPullFIFOSmokeTest, SmokeTests) {
+  const FIFOSmokeTestParam param = GetParam();
+  const double sample_rate = param.sample_rate * 4;
+
+  const double pull_interval_ms =
+      param.pull_buffer_size / sample_rate * 1000;
+  const double push_interval_ms =
+      param.push_buffer_size / sample_rate * 1000;
+
+  std::unique_ptr<PushPullFIFO> test_fifo = WTF::WrapUnique(
+      new PushPullFIFO(param.number_of_channels, param.fifo_length));
+  std::unique_ptr<PullClient> pull_client = WTF::WrapUnique(new PullClient(
+      test_fifo.get(), param.pull_buffer_size, param.pull_jitter_range_ms));
+  std::unique_ptr<PushClient> push_client = WTF::WrapUnique(new PushClient(
+      test_fifo.get(), param.push_buffer_size, param.push_jitter_range_ms));
+
+  LOG(INFO) << "PushPullFIFOSmokeTest - Start";
+
+  pull_client->Start(param.test_duration_ms, pull_interval_ms);
+  push_client->Start(param.test_duration_ms, push_interval_ms);
+
+  // If the operation does not cause a crash for the test period, it's passed.
+  // Also give a bit more time to finish the tear-down process.
+  HoldTestForDuration(param.test_duration_ms + 150);
+}
+
+FIFOSmokeTestParam smoke_test_params[] = {
+  // Test case 0 (OSX): 256 Pull, 128 Push, Minimal jitter.
+  // WebThread's priority is lower than the device thread, so its jitter range
+  // is slightly bigger than the other.
+  {48000, 2, 8192, 1000, 256, 1, 128, 2},
+
+  // Test case 1 (Windows): 480 Pull, 128 Push. Moderate Jitter.

[o1ka, 2017/04/25 08:23:22]

Since WebAudio has introduced user-specified buffer sizes, should the tests
cover both 10 ms and 20 ms pulls?

[hongchan, 2017/04/25 20:36:42]

10ms = 480. (in 48000Hz)

I can do 960 as well if that's what you mean.

By the way, you can see why I picked these numbers here:
https://docs.google.com/document/d/1WnqZHcA2TQjS1aKvzx2nnJ2y2tWK1Xp_0BhFGpsry...

+  // Windows' audio callback is known to be ~10ms and UMA data shows the
+  // evidence for it. The jitter range was determined speculatively.
+  {48000, 2, 8192, 1000, 480, 2, 128, 3},
+
+  // Test case 2 (Ubuntu/Linux): 512 Pull, 128 Push. Unstable callback, but
+  // fast CPU. A typical configuration for Ubuntu + PulseAudio setup.
+  // PulseAudio's callback is known to be rather unstable.
+  {48000, 2, 8192, 1000, 512, 8, 128, 1},
+
+  // Test case 3 (Android-Reference): 512 Pull, 128 Push. Similar to Linux, but
+  // low profile CPU.
+  {44100, 2, 8192, 1000, 512, 8, 128, 3},
+
+  // Test case 4 (Android-ExternalA): 441 Pull, 128 Push. Extreme jitter with
+  // low profile CPU.
+  {44100, 2, 8192, 1000, 441, 24, 128, 8},
+
+  // Test case 5 (Android-ExternalB): 5768 Pull, 128 Push. Huge callback with
+  // large jitter. Low profile CPU.
+  {44100, 2, 8192, 1000, 5768, 120, 128, 12}

[o1ka, 2017/04/25 08:23:22]

Consider running at least one test for a longer time, like 10 seconds?

[hongchan, 2017/04/25 20:36:42]

Good idea. Done.

+};
+
+INSTANTIATE_TEST_CASE_P(PushPullFIFOSmokeTest,
+                        PushPullFIFOSmokeTest,
+                        ::testing::ValuesIn(smoke_test_params));
+
+}  // namespace
+
+}  // namespace blink