Reduce taking locks in RTPSenderVideo::SendVideo

webrtc/modules/rtp_rtcp/source/rtp_sender_video.h

 /*
  *  Copyright (c) 2012 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 24 matching lines @@
 
 class RTPSenderVideo {
  public:
   RTPSenderVideo(Clock* clock,
                  RTPSender* rtpSender,
                  FlexfecSender* flexfec_sender);
   virtual ~RTPSenderVideo();
 
   virtual RtpVideoCodecTypes VideoCodecType() const;
 
-  size_t FecPacketOverhead() const;
+  size_t FecPacketOverhead() const {
+    rtc::CritScope cs(&crit_);
+    return CalculateFecPacketOverhead();
+  }
 
   static RtpUtility::Payload* CreateVideoPayload(
       const char payload_name[RTP_PAYLOAD_NAME_SIZE],
       int8_t payload_type);
 
   bool SendVideo(RtpVideoCodecTypes video_type,
                  FrameType frame_type,
                  int8_t payload_type,
                  uint32_t capture_timestamp,
                  int64_t capture_time_ms,
@@ skipping 11 matching lines @@
   void SetFecParameters(const FecProtectionParams& delta_params,
                         const FecProtectionParams& key_params);
 
   uint32_t VideoBitrateSent() const;
   uint32_t FecOverheadRate() const;
 
   int SelectiveRetransmissions() const;
   void SetSelectiveRetransmissions(uint8_t settings);
 
  private:
+  size_t CalculateFecPacketOverhead() const EXCLUSIVE_LOCKS_REQUIRED(crit_);
+
   void SendVideoPacket(std::unique_ptr<RtpPacketToSend> packet,
                        StorageType storage);
 
   void SendVideoPacketAsRedMaybeWithUlpfec(
       std::unique_ptr<RtpPacketToSend> media_packet,
       StorageType media_packet_storage,
       bool protect_media_packet);
 
   // TODO(brandtr): Remove the FlexFEC functions when FlexfecSender has been
   // moved to PacedSender.
@@ skipping 38 matching lines @@
   // and any padding overhead.
   RateStatistics fec_bitrate_ GUARDED_BY(stats_crit_);
   // Bitrate used for video payload and RTP headers.
   RateStatistics video_bitrate_ GUARDED_BY(stats_crit_);
   OneTimeEvent first_frame_sent_;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_RTP_RTCP_SOURCE_RTP_SENDER_VIDEO_H_