Revert "Reduce locking in VideoReceiver and check the threading model."
This reverts commit c75f1e45093a8d5cc62937c7708b87aa5c5bf0b0.
Reason for revert: Breaking internal project
Original change's description:
> Reduce locking in VideoReceiver and check the threading model.
>
> Note: This is a subset of code that was previously reviewed here:
> - https://codereview.webrtc.org/2764573002/
>
> * Added two notification methods, DecoderThreadStarting() and DecoderThreadStopped()
> * Allows us to establish a period when the decoder thread is not running and it is
> safe to modify variables such as callbacks, that are only read when the decoder
> thread is running.
> * Allows us to DCHECK thread guarantees/correctness.
> * Allows synchronizing callbacks from the module process thread and have them only
> active while the decoder thread is running.
> * The above, allows us to establish two modes for the thread,
> single-threaded-mutable and multi-threaded-const.
> * Using that knowledge, we can remove |receive_crit_| as well as locking for a
> number of member variables.
> * Removed |VCMFrameBuffer _frameFromFile| (unused).
> * Clean up several of my TODOs
>
> Bug: webrtc:7361, chromium:695438
> Change-Id: Id0048ee9624f76103c088d02825eb5c0d6c8913c
> Reviewed-on: https://webrtc-review.googlesource.com/55000
> Commit-Queue: Tommi <tommi@webrtc.org>
> Reviewed-by: Philip Eliasson <philipel@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#22133}
TBR=tommi@webrtc.org,philipel@webrtc.org
Change-Id: I4d78e8b2c05b36e1a3f64cb38d652579b3a23f22
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: webrtc:7361, chromium:695438
Reviewed-on: https://webrtc-review.googlesource.com/56280
Reviewed-by: Lu Liu <lliuu@webrtc.org>
Commit-Queue: Lu Liu <lliuu@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22141}diff --git a/modules/video_coding/video_coding_impl.h b/modules/video_coding/video_coding_impl.h
index 3b692d1..8a442c8 100644
--- a/modules/video_coding/video_coding_impl.h
+++ b/modules/video_coding/video_coding_impl.h
@@ -143,7 +143,7 @@
VCMTiming* timing,
NackSender* nack_sender = nullptr,
KeyFrameRequestSender* keyframe_request_sender = nullptr);
- ~VideoReceiver() override;
+ ~VideoReceiver();
int32_t RegisterReceiveCodec(const VideoCodec* receiveCodec,
int32_t numberOfCores,
@@ -161,6 +161,9 @@
int32_t Decode(const webrtc::VCMEncodedFrame* frame);
+ // Called on the decoder thread when thread is exiting.
+ void DecodingStopped();
+
int32_t IncomingPacket(const uint8_t* incomingPayload,
size_t payloadLength,
const WebRtcRTPHeader& rtpInfo);
@@ -185,72 +188,41 @@
int64_t TimeUntilNextProcess() override;
void Process() override;
- void ProcessThreadAttached(ProcessThread* process_thread) override;
void TriggerDecoderShutdown();
- // Notification methods that are used to check our internal state and validate
- // threading assumptions. These are called by VideoReceiveStream.
- // See |IsDecoderThreadRunning()| for more details.
- void DecoderThreadStarting();
- void DecoderThreadStopped();
-
protected:
- int32_t Decode(const webrtc::VCMEncodedFrame& frame);
+ int32_t Decode(const webrtc::VCMEncodedFrame& frame)
+ RTC_EXCLUSIVE_LOCKS_REQUIRED(receive_crit_);
int32_t RequestKeyFrame();
private:
- // Used for DCHECKing thread correctness.
- // In build where DCHECKs are enabled, will return false before
- // DecoderThreadStarting is called, then true until DecoderThreadStopped
- // is called.
- // In builds where DCHECKs aren't enabled, it will return true.
- bool IsDecoderThreadRunning();
-
- rtc::ThreadChecker construction_thread_checker_;
- rtc::ThreadChecker decoder_thread_checker_;
- rtc::ThreadChecker module_thread_checker_;
+ rtc::ThreadChecker construction_thread_;
Clock* const clock_;
rtc::CriticalSection process_crit_;
+ rtc::CriticalSection receive_crit_;
VCMTiming* _timing;
VCMReceiver _receiver;
VCMDecodedFrameCallback _decodedFrameCallback;
+ VCMFrameTypeCallback* _frameTypeCallback RTC_GUARDED_BY(process_crit_);
+ VCMReceiveStatisticsCallback* _receiveStatsCallback
+ RTC_GUARDED_BY(process_crit_);
+ VCMPacketRequestCallback* _packetRequestCallback
+ RTC_GUARDED_BY(process_crit_);
- // These callbacks are set on the construction thread before being attached
- // to the module thread or decoding started, so a lock is not required.
- VCMFrameTypeCallback* _frameTypeCallback;
- VCMReceiveStatisticsCallback* _receiveStatsCallback;
- VCMPacketRequestCallback* _packetRequestCallback;
-
- // Used on both the module and decoder thread.
+ VCMFrameBuffer _frameFromFile;
bool _scheduleKeyRequest RTC_GUARDED_BY(process_crit_);
bool drop_frames_until_keyframe_ RTC_GUARDED_BY(process_crit_);
+ size_t max_nack_list_size_ RTC_GUARDED_BY(process_crit_);
- // Modified on the construction thread while not attached to the process
- // thread. Once attached to the process thread, its value is only read
- // so a lock is not required.
- size_t max_nack_list_size_;
+ VCMDecoderDataBase _codecDataBase RTC_GUARDED_BY(receive_crit_);
+ EncodedImageCallback* pre_decode_image_callback_;
- // Callbacks are set before the decoder thread starts.
- // Once the decoder thread has been started, usage of |_codecDataBase| moves
- // over to the decoder thread.
- VCMDecoderDataBase _codecDataBase;
- EncodedImageCallback* const pre_decode_image_callback_;
-
- VCMProcessTimer _receiveStatsTimer RTC_GUARDED_BY(module_thread_checker_);
- VCMProcessTimer _retransmissionTimer RTC_GUARDED_BY(module_thread_checker_);
- VCMProcessTimer _keyRequestTimer RTC_GUARDED_BY(module_thread_checker_);
- QpParser qp_parser_ RTC_GUARDED_BY(decoder_thread_checker_);
- ThreadUnsafeOneTimeEvent first_frame_received_
- RTC_GUARDED_BY(decoder_thread_checker_);
- // Modified on the construction thread. Can be read without a lock and assumed
- // to be non-null on the module and decoder threads.
- ProcessThread* process_thread_ = nullptr;
- bool is_attached_to_process_thread_
- RTC_GUARDED_BY(construction_thread_checker_) = false;
-#if RTC_DCHECK_IS_ON
- bool decoder_thread_is_running_ = false;
-#endif
+ VCMProcessTimer _receiveStatsTimer;
+ VCMProcessTimer _retransmissionTimer;
+ VCMProcessTimer _keyRequestTimer;
+ QpParser qp_parser_;
+ ThreadUnsafeOneTimeEvent first_frame_received_;
};
} // namespace vcm