Lock scheme #8: Introduced the new locking scheme

webrtc/modules/audio_processing/echo_control_mobile_impl.cc

Index: webrtc/modules/audio_processing/echo_control_mobile_impl.cc
diff --git a/webrtc/modules/audio_processing/echo_control_mobile_impl.cc b/webrtc/modules/audio_processing/echo_control_mobile_impl.cc
index a32c77c1420cdbbc62032bc38bc1cb3119d89b6f..5ff7bd728d2a9a51dbe56b096697e45d96dfa746 100644
--- a/webrtc/modules/audio_processing/echo_control_mobile_impl.cc
+++ b/webrtc/modules/audio_processing/echo_control_mobile_impl.cc
@@ -15,7 +15,6 @@
 
 #include "webrtc/modules/audio_processing/aecm/echo_control_mobile.h"
 #include "webrtc/modules/audio_processing/audio_buffer.h"
-#include "webrtc/system_wrappers/include/critical_section_wrapper.h"
 #include "webrtc/system_wrappers/include/logging.h"
 
 namespace webrtc {
@@ -69,14 +68,20 @@ size_t EchoControlMobile::echo_path_size_bytes() {
 }
 
 EchoControlMobileImpl::EchoControlMobileImpl(const AudioProcessing* apm,
-                                             CriticalSectionWrapper* crit)
+                                             rtc::CriticalSection* crit_render,
+                                             rtc::CriticalSection* crit_capture)
     : ProcessingComponent(),
       apm_(apm),
-      crit_(crit),
+      crit_render_(crit_render),
+      crit_capture_(crit_capture),
       routing_mode_(kSpeakerphone),
       comfort_noise_enabled_(true),
       external_echo_path_(NULL),
-      render_queue_element_max_size_(0) {}
+      render_queue_element_max_size_(0) {
+  RTC_DCHECK(apm);
+  RTC_DCHECK(crit_render);
+  RTC_DCHECK(crit_capture);
+}
 
 EchoControlMobileImpl::~EchoControlMobileImpl() {
     if (external_echo_path_ != NULL) {
@@ -86,15 +91,16 @@ EchoControlMobileImpl::~EchoControlMobileImpl() {
 }
 
 int EchoControlMobileImpl::ProcessRenderAudio(const AudioBuffer* audio) {
+  rtc::CritScope cs_render(crit_render_);
+
   if (!is_component_enabled()) {
-    return apm_->kNoError;
+    return AudioProcessing::kNoError;
   }
 
   assert(audio->num_frames_per_band() <= 160);
   assert(audio->num_channels() == apm_->num_reverse_channels());
 
-  int err = apm_->kNoError;
-
+  int err = AudioProcessing::kNoError;
   // The ordering convention must be followed to pass to the correct AECM.
   size_t handle_index = 0;
   render_queue_buffer_.clear();
@@ -105,7 +111,7 @@ int EchoControlMobileImpl::ProcessRenderAudio(const AudioBuffer* audio) {
           my_handle, audio->split_bands_const(j)[kBand0To8kHz],
           audio->num_frames_per_band());
 
-      if (err != apm_->kNoError)
+      if (err != AudioProcessing::kNoError)
         return MapError(err);  // TODO(ajm): warning possible?);
 
       // Buffer the samples in the render queue.
@@ -120,18 +126,21 @@ int EchoControlMobileImpl::ProcessRenderAudio(const AudioBuffer* audio) {
 
   // Insert the samples into the queue.
   if (!render_signal_queue_->Insert(&render_queue_buffer_)) {
+    // The data queue is full and needs to be emptied.
     ReadQueuedRenderData();
 
     // Retry the insert (should always work).
     RTC_DCHECK_EQ(render_signal_queue_->Insert(&render_queue_buffer_), true);
   }
 
-  return apm_->kNoError;
+  return AudioProcessing::kNoError;
 }
 
 // Read chunks of data that were received and queued on the render side from
 // a queue. All the data chunks are buffered into the farend signal of the AEC.
 void EchoControlMobileImpl::ReadQueuedRenderData() {
+  rtc::CritScope cs_capture(crit_capture_);
+
   if (!is_component_enabled()) {
     return;
   }
@@ -156,18 +165,20 @@ void EchoControlMobileImpl::ReadQueuedRenderData() {
 }
 
 int EchoControlMobileImpl::ProcessCaptureAudio(AudioBuffer* audio) {
+  rtc::CritScope cs_capture(crit_capture_);
+
   if (!is_component_enabled()) {
-    return apm_->kNoError;
+    return AudioProcessing::kNoError;
   }
 
   if (!apm_->was_stream_delay_set()) {
-    return apm_->kStreamParameterNotSetError;
+    return AudioProcessing::kStreamParameterNotSetError;
   }
 
   assert(audio->num_frames_per_band() <= 160);
   assert(audio->num_channels() == apm_->num_output_channels());
 
-  int err = apm_->kNoError;
+  int err = AudioProcessing::kNoError;
 
   // The ordering convention must be followed to pass to the correct AECM.
   size_t handle_index = 0;
@@ -190,86 +201,99 @@ int EchoControlMobileImpl::ProcessCaptureAudio(AudioBuffer* audio) {
           audio->num_frames_per_band(),
           apm_->stream_delay_ms());
 
-      if (err != apm_->kNoError)
+      if (err != AudioProcessing::kNoError)
         return MapError(err);
 
       handle_index++;
     }
   }
 
-  return apm_->kNoError;
+  return AudioProcessing::kNoError;
 }
 
 int EchoControlMobileImpl::Enable(bool enable) {
-  CriticalSectionScoped crit_scoped(crit_);
   // Ensure AEC and AECM are not both enabled.
+  rtc::CritScope cs_render(crit_render_);
+  rtc::CritScope cs_capture(crit_capture_);
+  // The is_enabled call is safe from a deadlock perspective
+  // as both locks are allready held in the correct order.
   if (enable && apm_->echo_cancellation()->is_enabled()) {
-    return apm_->kBadParameterError;
+    return AudioProcessing::kBadParameterError;
   }
 
   return EnableComponent(enable);
 }
 
 bool EchoControlMobileImpl::is_enabled() const {
+  rtc::CritScope cs(crit_capture_);
   return is_component_enabled();
 }
 
 int EchoControlMobileImpl::set_routing_mode(RoutingMode mode) {
-  CriticalSectionScoped crit_scoped(crit_);
   if (MapSetting(mode) == -1) {
-    return apm_->kBadParameterError;
+    return AudioProcessing::kBadParameterError;
   }
 
-  routing_mode_ = mode;
+  {
+    rtc::CritScope cs(crit_capture_);
+    routing_mode_ = mode;
+  }
   return Configure();
 }
 
 EchoControlMobile::RoutingMode EchoControlMobileImpl::routing_mode()
     const {
+  rtc::CritScope cs(crit_capture_);
   return routing_mode_;
 }
 
 int EchoControlMobileImpl::enable_comfort_noise(bool enable) {
-  CriticalSectionScoped crit_scoped(crit_);
-  comfort_noise_enabled_ = enable;
+  {
+    rtc::CritScope cs(crit_capture_);
+    comfort_noise_enabled_ = enable;
+  }
   return Configure();
 }
 
 bool EchoControlMobileImpl::is_comfort_noise_enabled() const {
+  rtc::CritScope cs(crit_capture_);
   return comfort_noise_enabled_;
 }
 
 int EchoControlMobileImpl::SetEchoPath(const void* echo_path,
                                        size_t size_bytes) {
-  CriticalSectionScoped crit_scoped(crit_);
-  if (echo_path == NULL) {
-    return apm_->kNullPointerError;
-  }
-  if (size_bytes != echo_path_size_bytes()) {
-    // Size mismatch
-    return apm_->kBadParameterError;
-  }
+  {
+    rtc::CritScope cs_render(crit_render_);
+    rtc::CritScope cs_capture(crit_capture_);
+    if (echo_path == NULL) {
+      return AudioProcessing::kNullPointerError;
+    }
+    if (size_bytes != echo_path_size_bytes()) {
+      // Size mismatch
+      return AudioProcessing::kBadParameterError;
+    }
 
-  if (external_echo_path_ == NULL) {
-    external_echo_path_ = new unsigned char[size_bytes];
+    if (external_echo_path_ == NULL) {
+      external_echo_path_ = new unsigned char[size_bytes];
+    }
+    memcpy(external_echo_path_, echo_path, size_bytes);
   }
-  memcpy(external_echo_path_, echo_path, size_bytes);
 
   return Initialize();
 }
 
 int EchoControlMobileImpl::GetEchoPath(void* echo_path,
                                        size_t size_bytes) const {
-  CriticalSectionScoped crit_scoped(crit_);
+  rtc::CritScope cs(crit_capture_);
   if (echo_path == NULL) {
-    return apm_->kNullPointerError;
+    return AudioProcessing::kNullPointerError;
   }
   if (size_bytes != echo_path_size_bytes()) {
     // Size mismatch
-    return apm_->kBadParameterError;
+    return AudioProcessing::kBadParameterError;
   }
   if (!is_component_enabled()) {
-    return apm_->kNotEnabledError;
+    return AudioProcessing::kNotEnabledError;
   }
 
   // Get the echo path from the first channel
@@ -278,27 +302,30 @@ int EchoControlMobileImpl::GetEchoPath(void* echo_path,
   if (err != 0)
     return MapError(err);
 
-  return apm_->kNoError;
+  return AudioProcessing::kNoError;
 }
 
 int EchoControlMobileImpl::Initialize() {
-  if (!is_component_enabled()) {
-    return apm_->kNoError;
+  {
+    rtc::CritScope cs_capture(crit_capture_);
+    if (!is_component_enabled()) {
+      return AudioProcessing::kNoError;
+    }
   }
 
-  if (apm_->proc_sample_rate_hz() > apm_->kSampleRate16kHz) {
+  if (apm_->proc_sample_rate_hz() > AudioProcessing::kSampleRate16kHz) {
     LOG(LS_ERROR) << "AECM only supports 16 kHz or lower sample rates";
-    return apm_->kBadSampleRateError;
+    return AudioProcessing::kBadSampleRateError;
   }
 
   int err = ProcessingComponent::Initialize();
-  if (err != apm_->kNoError) {
+  if (err != AudioProcessing::kNoError) {
     return err;
   }
 
   AllocateRenderQueue();
 
-  return apm_->kNoError;
+  return AudioProcessing::kNoError;
 }
 
 void EchoControlMobileImpl::AllocateRenderQueue() {
@@ -306,6 +333,9 @@ void EchoControlMobileImpl::AllocateRenderQueue() {
       static_cast<size_t>(1),
       kMaxAllowedValuesOfSamplesPerFrame * num_handles_required());
 
+  rtc::CritScope cs_render(crit_render_);
+  rtc::CritScope cs_capture(crit_capture_);
+
   // Reallocate the queue if the queue item size is too small to fit the
   // data to put in the queue.
   if (render_queue_element_max_size_ < new_render_queue_element_max_size) {
@@ -330,10 +360,14 @@ void* EchoControlMobileImpl::CreateHandle() const {
 }
 
 void EchoControlMobileImpl::DestroyHandle(void* handle) const {
+  // This method is only called in a non-concurrent manner during APM
+  // destruction.
   WebRtcAecm_Free(static_cast<Handle*>(handle));
 }
 
 int EchoControlMobileImpl::InitializeHandle(void* handle) const {
+  rtc::CritScope cs_render(crit_render_);
+  rtc::CritScope cs_capture(crit_capture_);
   assert(handle != NULL);
   Handle* my_handle = static_cast<Handle*>(handle);
   if (WebRtcAecm_Init(my_handle, apm_->proc_sample_rate_hz()) != 0) {
@@ -347,10 +381,12 @@ int EchoControlMobileImpl::InitializeHandle(void* handle) const {
     }
   }
 
-  return apm_->kNoError;
+  return AudioProcessing::kNoError;
 }
 
 int EchoControlMobileImpl::ConfigureHandle(void* handle) const {
+  rtc::CritScope cs_render(crit_render_);
+  rtc::CritScope cs_capture(crit_capture_);
   AecmConfig config;
   config.cngMode = comfort_noise_enabled_;
   config.echoMode = MapSetting(routing_mode_);
@@ -359,11 +395,13 @@ int EchoControlMobileImpl::ConfigureHandle(void* handle) const {
 }
 
 int EchoControlMobileImpl::num_handles_required() const {
+  // Not locked as it only relies on APM public API which is threadsafe.
   return apm_->num_output_channels() *
          apm_->num_reverse_channels();
 }
 
 int EchoControlMobileImpl::GetHandleError(void* handle) const {
+  // Not locked as it does not rely on anything in the state.
   assert(handle != NULL);
   return AudioProcessing::kUnspecifiedError;
 }