Refactor how padding is calculated.

webrtc/call/call.cc

 /*
  *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 37 matching lines @@
 #include "webrtc/voice_engine/include/voe_codec.h"
 
 namespace webrtc {
 
 const int Call::Config::kDefaultStartBitrateBps = 300000;
 
 namespace internal {
 
 class Call : public webrtc::Call,
              public PacketReceiver,
-             public CongestionController::Observer {
+             public CongestionController::Observer,
+             public BitrateAllocator::LimitObserver {
  public:
   explicit Call(const Call::Config& config);
   virtual ~Call();
 
   PacketReceiver* Receiver() override;
 
   webrtc::AudioSendStream* CreateAudioSendStream(
       const webrtc::AudioSendStream::Config& config) override;
   void DestroyAudioSendStream(webrtc::AudioSendStream* send_stream) override;
 
@@ skipping 26 matching lines @@
 
   void OnNetworkRouteChanged(const std::string& transport_name,
                              const rtc::NetworkRoute& network_route) override;
 
   void OnSentPacket(const rtc::SentPacket& sent_packet) override;
 
   // Implements BitrateObserver.
   void OnNetworkChanged(uint32_t bitrate_bps, uint8_t fraction_loss,
                         int64_t rtt_ms) override;
 
+  // Implements BitrateAllocator::LimitObserver.
+  void OnAllocationLimitsChanged(uint32_t min_send_bitrate_bps,
+                                 uint32_t max_padding_bitrate_bps) override;
+
  private:
   DeliveryStatus DeliverRtcp(MediaType media_type, const uint8_t* packet,
                              size_t length);
   DeliveryStatus DeliverRtp(MediaType media_type,
                             const uint8_t* packet,
                             size_t length,
                             const PacketTime& packet_time);
   void ConfigureSync(const std::string& sync_group)
       EXCLUSIVE_LOCKS_REQUIRED(receive_crit_);
 
@@ skipping 52 matching lines @@
   int64_t received_rtcp_bytes_;
   int64_t first_rtp_packet_received_ms_;
   int64_t last_rtp_packet_received_ms_;
   int64_t first_packet_sent_ms_;
 
   // TODO(holmer): Remove this lock once BitrateController no longer calls
   // OnNetworkChanged from multiple threads.
   rtc::CriticalSection bitrate_crit_;
   int64_t estimated_send_bitrate_sum_kbits_ GUARDED_BY(&bitrate_crit_);
   int64_t pacer_bitrate_sum_kbits_ GUARDED_BY(&bitrate_crit_);
+  uint32_t min_allocated_send_bitrate_bps_ GUARDED_BY(&bitrate_crit_);
   int64_t num_bitrate_updates_ GUARDED_BY(&bitrate_crit_);
 
   std::map<std::string, rtc::NetworkRoute> network_routes_;
 
   VieRemb remb_;
   const std::unique_ptr<CongestionController> congestion_controller_;
   const std::unique_ptr<SendDelayStats> video_send_delay_stats_;
 
   RTC_DISALLOW_COPY_AND_ASSIGN(Call);
 };
 }  // namespace internal
 
 Call* Call::Create(const Call::Config& config) {
   return new internal::Call(config);
 }
 
 namespace internal {
 
 Call::Call(const Call::Config& config)
     : clock_(Clock::GetRealTimeClock()),
       num_cpu_cores_(CpuInfo::DetectNumberOfCores()),
       module_process_thread_(ProcessThread::Create("ModuleProcessThread")),
       pacer_thread_(ProcessThread::Create("PacerThread")),
       call_stats_(new CallStats(clock_)),
-      bitrate_allocator_(new BitrateAllocator()),
+      bitrate_allocator_(new BitrateAllocator(this)),
       config_(config),
       audio_network_state_(kNetworkUp),
       video_network_state_(kNetworkUp),
       receive_crit_(RWLockWrapper::CreateRWLock()),
       send_crit_(RWLockWrapper::CreateRWLock()),
       received_video_bytes_(0),
       received_audio_bytes_(0),
       received_rtcp_bytes_(0),
       first_rtp_packet_received_ms_(-1),
       last_rtp_packet_received_ms_(-1),
       first_packet_sent_ms_(-1),
       estimated_send_bitrate_sum_kbits_(0),
       pacer_bitrate_sum_kbits_(0),
+      min_allocated_send_bitrate_bps_(0),
       num_bitrate_updates_(0),
       remb_(clock_),
       congestion_controller_(new CongestionController(clock_, this, &remb_)),
       video_send_delay_stats_(new SendDelayStats(clock_)) {
   RTC_DCHECK(configuration_thread_checker_.CalledOnValidThread());
   RTC_DCHECK_GE(config.bitrate_config.min_bitrate_bps, 0);
   RTC_DCHECK_GE(config.bitrate_config.start_bitrate_bps,
                 config.bitrate_config.min_bitrate_bps);
   if (config.bitrate_config.max_bitrate_bps != -1) {
     RTC_DCHECK_GE(config.bitrate_config.max_bitrate_bps,
@@ skipping 445 matching lines @@
 void Call::OnSentPacket(const rtc::SentPacket& sent_packet) {
   if (first_packet_sent_ms_ == -1)
     first_packet_sent_ms_ = clock_->TimeInMilliseconds();
   video_send_delay_stats_->OnSentPacket(sent_packet.packet_id,
                                         clock_->TimeInMilliseconds());
   congestion_controller_->OnSentPacket(sent_packet);
 }
 
 void Call::OnNetworkChanged(uint32_t target_bitrate_bps, uint8_t fraction_loss,
                             int64_t rtt_ms) {
-  uint32_t allocated_bitrate_bps = bitrate_allocator_->OnNetworkChanged(
-      target_bitrate_bps, fraction_loss, rtt_ms);
+  bitrate_allocator_->OnNetworkChanged(target_bitrate_bps, fraction_loss,
+                                       rtt_ms);
 
-  int pad_up_to_bitrate_bps = 0;
-  {
-    ReadLockScoped read_lock(*send_crit_);
-    // No need to update as long as we're not sending.
-    if (video_send_streams_.empty())
-      return;
-
-    for (VideoSendStream* stream : video_send_streams_)
-      pad_up_to_bitrate_bps += stream->GetPaddingNeededBps();
-  }
-  // Allocated bitrate might be higher than bitrate estimate if enforcing min
-  // bitrate, or lower if estimate is higher than the sum of max bitrates, so
-  // set the pacer bitrate to the maximum of the two.
-  uint32_t pacer_bitrate_bps =
-      std::max(target_bitrate_bps, allocated_bitrate_bps);
   {
     rtc::CritScope lock(&bitrate_crit_);
     // We only update these stats if we have send streams, and assume that
     // OnNetworkChanged is called roughly with a fixed frequency.
     estimated_send_bitrate_sum_kbits_ += target_bitrate_bps / 1000;
+    // Pacer bitrate might be higher than bitrate estimate if enforcing min
+    // bitrate.
+    uint32_t pacer_bitrate_bps =
+        std::max(target_bitrate_bps, min_allocated_send_bitrate_bps_);
     pacer_bitrate_sum_kbits_ += pacer_bitrate_bps / 1000;
     ++num_bitrate_updates_;
   }
+}
 
-  // Make sure to not ask for more padding than the current BWE allows for.
-  pad_up_to_bitrate_bps = std::min(static_cast<uint32_t>(pad_up_to_bitrate_bps),
-                                   target_bitrate_bps);
-  congestion_controller_->SetAllocatedSendBitrate(allocated_bitrate_bps,
-                                                  pad_up_to_bitrate_bps);
+void Call::OnAllocationLimitsChanged(uint32_t min_send_bitrate_bps,
+                                     uint32_t max_padding_bitrate_bps) {
+  congestion_controller_->SetAllocatedSendBitrateLimits(
+      min_send_bitrate_bps, max_padding_bitrate_bps);
+  rtc::CritScope lock(&bitrate_crit_);
+  min_allocated_send_bitrate_bps_ = min_send_bitrate_bps;
 }
 
 void Call::ConfigureSync(const std::string& sync_group) {
   // Set sync only if there was no previous one.
   if (voice_engine() == nullptr || sync_group.empty())
     return;
 
   AudioReceiveStream* sync_audio_stream = nullptr;
   // Find existing audio stream.
   const auto it = sync_stream_mapping_.find(sync_group);
@@ skipping 133 matching lines @@
   // thread. Then this check can be enabled.
   // RTC_DCHECK(!configuration_thread_checker_.CalledOnValidThread());
   if (RtpHeaderParser::IsRtcp(packet, length))
     return DeliverRtcp(media_type, packet, length);
 
   return DeliverRtp(media_type, packet, length, packet_time);
 }
 
 }  // namespace internal
 }  // namespace webrtc