webrtc_m130/modules/pacing/packet_router.h
Erik Språng 478cb46435 Add GeneratePadding method to replace TimeToSendPadding
Unlike TimeToSendPadding(), the new GeneratePadding() method will
generate RTP packets and put them in the pacer queue, which will be
responsible for actually sending them.

A slight difference from previous logic is that we do not use a lower
bound of 50bytes for getting payload packets, instead we always try and
then abort if the next padding packet is larger than the current
available budget.

Since we're not sending the packets immediately, we don't need to worry
about twcc sequence numbering or updating the stats, that will be
handled by the general SendPacket() codepath. We can also omit the
PacingInfo struct and the return value of bytes sent, as that will
be handled when taking the packets out of the queue.

Bug: webrtc:10633
Change-Id: I066c292805a0bf76c59f68e66c21ea23fdb56c03
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/143794
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Reviewed-by: Sebastian Jansson <srte@webrtc.org>
Commit-Queue: Erik Språng <sprang@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#28403}
2019-06-27 13:39:05 +00:00

141 lines
5.4 KiB
C++

/*
* Copyright (c) 2015 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.
*/
#ifndef MODULES_PACING_PACKET_ROUTER_H_
#define MODULES_PACING_PACKET_ROUTER_H_
#include <stddef.h>
#include <stdint.h>
#include <list>
#include <memory>
#include <unordered_map>
#include <vector>
#include "api/transport/network_types.h"
#include "modules/remote_bitrate_estimator/include/remote_bitrate_estimator.h"
#include "modules/rtp_rtcp/include/rtp_rtcp_defines.h"
#include "modules/rtp_rtcp/source/rtp_packet_to_send.h"
#include "rtc_base/constructor_magic.h"
#include "rtc_base/critical_section.h"
#include "rtc_base/thread_annotations.h"
namespace webrtc {
class RtpRtcp;
namespace rtcp {
class TransportFeedback;
} // namespace rtcp
// PacketRouter keeps track of rtp send modules to support the pacer.
// In addition, it handles feedback messages, which are sent on a send
// module if possible (sender report), otherwise on receive module
// (receiver report). For the latter case, we also keep track of the
// receive modules.
class PacketRouter : public TransportSequenceNumberAllocator,
public RemoteBitrateObserver,
public TransportFeedbackSenderInterface {
public:
PacketRouter();
~PacketRouter() override;
void AddSendRtpModule(RtpRtcp* rtp_module, bool remb_candidate);
void RemoveSendRtpModule(RtpRtcp* rtp_module);
void AddReceiveRtpModule(RtcpFeedbackSenderInterface* rtcp_sender,
bool remb_candidate);
void RemoveReceiveRtpModule(RtcpFeedbackSenderInterface* rtcp_sender);
virtual RtpPacketSendResult TimeToSendPacket(
uint32_t ssrc,
uint16_t sequence_number,
int64_t capture_timestamp,
bool retransmission,
const PacedPacketInfo& packet_info);
virtual void SendPacket(std::unique_ptr<RtpPacketToSend> packet,
const PacedPacketInfo& cluster_info);
virtual size_t TimeToSendPadding(size_t bytes,
const PacedPacketInfo& packet_info);
virtual void GeneratePadding(size_t target_size_bytes);
void SetTransportWideSequenceNumber(uint16_t sequence_number);
uint16_t AllocateSequenceNumber() override;
// Called every time there is a new bitrate estimate for a receive channel
// group. This call will trigger a new RTCP REMB packet if the bitrate
// estimate has decreased or if no RTCP REMB packet has been sent for
// a certain time interval.
// Implements RtpReceiveBitrateUpdate.
void OnReceiveBitrateChanged(const std::vector<uint32_t>& ssrcs,
uint32_t bitrate_bps) override;
// Ensures remote party notified of the receive bitrate limit no larger than
// |bitrate_bps|.
void SetMaxDesiredReceiveBitrate(int64_t bitrate_bps);
// Send REMB feedback.
bool SendRemb(int64_t bitrate_bps, const std::vector<uint32_t>& ssrcs);
// Send transport feedback packet to send-side.
bool SendTransportFeedback(rtcp::TransportFeedback* packet) override;
private:
RtpRtcp* FindRtpModule(uint32_t ssrc)
RTC_EXCLUSIVE_LOCKS_REQUIRED(modules_crit_);
void AddRembModuleCandidate(RtcpFeedbackSenderInterface* candidate_module,
bool media_sender)
RTC_EXCLUSIVE_LOCKS_REQUIRED(modules_crit_);
void MaybeRemoveRembModuleCandidate(
RtcpFeedbackSenderInterface* candidate_module,
bool media_sender) RTC_EXCLUSIVE_LOCKS_REQUIRED(modules_crit_);
void UnsetActiveRembModule() RTC_EXCLUSIVE_LOCKS_REQUIRED(modules_crit_);
void DetermineActiveRembModule() RTC_EXCLUSIVE_LOCKS_REQUIRED(modules_crit_);
rtc::CriticalSection modules_crit_;
// Rtp and Rtcp modules of the rtp senders.
std::list<RtpRtcp*> rtp_send_modules_ RTC_GUARDED_BY(modules_crit_);
// Ssrc to RtpRtcp module cache.
std::unordered_map<uint32_t, RtpRtcp*> rtp_module_cache_map_
RTC_GUARDED_BY(modules_crit_);
// The last module used to send media.
RtpRtcp* last_send_module_ RTC_GUARDED_BY(modules_crit_);
// Rtcp modules of the rtp receivers.
std::vector<RtcpFeedbackSenderInterface*> rtcp_feedback_senders_
RTC_GUARDED_BY(modules_crit_);
// TODO(eladalon): remb_crit_ only ever held from one function, and it's not
// clear if that function can actually be called from more than one thread.
rtc::CriticalSection remb_crit_;
// The last time a REMB was sent.
int64_t last_remb_time_ms_ RTC_GUARDED_BY(remb_crit_);
int64_t last_send_bitrate_bps_ RTC_GUARDED_BY(remb_crit_);
// The last bitrate update.
int64_t bitrate_bps_ RTC_GUARDED_BY(remb_crit_);
int64_t max_bitrate_bps_ RTC_GUARDED_BY(remb_crit_);
// Candidates for the REMB module can be RTP sender/receiver modules, with
// the sender modules taking precedence.
std::vector<RtcpFeedbackSenderInterface*> sender_remb_candidates_
RTC_GUARDED_BY(modules_crit_);
std::vector<RtcpFeedbackSenderInterface*> receiver_remb_candidates_
RTC_GUARDED_BY(modules_crit_);
RtcpFeedbackSenderInterface* active_remb_module_
RTC_GUARDED_BY(modules_crit_);
volatile int transport_seq_;
RTC_DISALLOW_COPY_AND_ASSIGN(PacketRouter);
};
} // namespace webrtc
#endif // MODULES_PACING_PACKET_ROUTER_H_