blob: 0adb4362865e425d104da09dd70fd9c55868d145 [file] [log] [blame]
/*
* Copyright (c) 2019 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.
*/
#include "modules/rtp_rtcp/source/rtp_sender_egress.h"
#include <algorithm>
#include <limits>
#include <memory>
#include <utility>
#include "absl/strings/match.h"
#include "api/units/timestamp.h"
#include "logging/rtc_event_log/events/rtc_event_rtp_packet_outgoing.h"
#include "rtc_base/logging.h"
namespace webrtc {
namespace {
constexpr uint32_t kTimestampTicksPerMs = 90;
constexpr TimeDelta kSendSideDelayWindow = TimeDelta::Seconds(1);
constexpr int kBitrateStatisticsWindowMs = 1000;
constexpr size_t kRtpSequenceNumberMapMaxEntries = 1 << 13;
constexpr TimeDelta kUpdateInterval =
TimeDelta::Millis(kBitrateStatisticsWindowMs);
} // namespace
RtpSenderEgress::NonPacedPacketSender::NonPacedPacketSender(
TaskQueueBase& worker_queue,
RtpSenderEgress* sender,
PacketSequencer* sequencer)
: worker_queue_(worker_queue),
transport_sequence_number_(0),
sender_(sender),
sequencer_(sequencer) {
RTC_DCHECK(sequencer);
}
RtpSenderEgress::NonPacedPacketSender::~NonPacedPacketSender() {
RTC_DCHECK_RUN_ON(&worker_queue_);
}
void RtpSenderEgress::NonPacedPacketSender::EnqueuePackets(
std::vector<std::unique_ptr<RtpPacketToSend>> packets) {
if (!worker_queue_.IsCurrent()) {
worker_queue_.PostTask(SafeTask(
task_safety_.flag(), [this, packets = std::move(packets)]() mutable {
EnqueuePackets(std::move(packets));
}));
return;
}
RTC_DCHECK_RUN_ON(&worker_queue_);
for (auto& packet : packets) {
PrepareForSend(packet.get());
sender_->SendPacket(std::move(packet), PacedPacketInfo());
}
auto fec_packets = sender_->FetchFecPackets();
if (!fec_packets.empty()) {
EnqueuePackets(std::move(fec_packets));
}
}
void RtpSenderEgress::NonPacedPacketSender::PrepareForSend(
RtpPacketToSend* packet) {
RTC_DCHECK_RUN_ON(&worker_queue_);
// Assign sequence numbers, but not for flexfec which is already running on
// an internally maintained sequence number series.
if (packet->Ssrc() != sender_->FlexFecSsrc()) {
sequencer_->Sequence(*packet);
}
if (!packet->SetExtension<TransportSequenceNumber>(
++transport_sequence_number_)) {
--transport_sequence_number_;
}
packet->ReserveExtension<TransmissionOffset>();
packet->ReserveExtension<AbsoluteSendTime>();
}
RtpSenderEgress::RtpSenderEgress(const RtpRtcpInterface::Configuration& config,
RtpPacketHistory* packet_history)
: enable_send_packet_batching_(config.enable_send_packet_batching),
worker_queue_(TaskQueueBase::Current()),
ssrc_(config.local_media_ssrc),
rtx_ssrc_(config.rtx_send_ssrc),
flexfec_ssrc_(config.fec_generator ? config.fec_generator->FecSsrc()
: absl::nullopt),
populate_network2_timestamp_(config.populate_network2_timestamp),
clock_(config.clock),
packet_history_(packet_history),
transport_(config.outgoing_transport),
event_log_(config.event_log),
is_audio_(config.audio),
need_rtp_packet_infos_(config.need_rtp_packet_infos),
fec_generator_(config.fec_generator),
transport_feedback_observer_(config.transport_feedback_callback),
send_side_delay_observer_(config.send_side_delay_observer),
send_packet_observer_(config.send_packet_observer),
rtp_stats_callback_(config.rtp_stats_callback),
bitrate_callback_(config.send_bitrate_observer),
media_has_been_sent_(false),
force_part_of_allocation_(false),
timestamp_offset_(0),
max_delay_it_(send_delays_.end()),
sum_delays_(TimeDelta::Zero()),
send_rates_(kNumMediaTypes,
{kBitrateStatisticsWindowMs, RateStatistics::kBpsScale}),
rtp_sequence_number_map_(need_rtp_packet_infos_
? std::make_unique<RtpSequenceNumberMap>(
kRtpSequenceNumberMapMaxEntries)
: nullptr) {
RTC_DCHECK(worker_queue_);
if (bitrate_callback_) {
update_task_ = RepeatingTaskHandle::DelayedStart(worker_queue_,
kUpdateInterval, [this]() {
PeriodicUpdate();
return kUpdateInterval;
});
}
}
RtpSenderEgress::~RtpSenderEgress() {
RTC_DCHECK_RUN_ON(worker_queue_);
update_task_.Stop();
}
void RtpSenderEgress::SendPacket(std::unique_ptr<RtpPacketToSend> packet,
const PacedPacketInfo& pacing_info) {
RTC_DCHECK_RUN_ON(worker_queue_);
RTC_DCHECK(packet);
if (packet->Ssrc() == ssrc_ &&
packet->packet_type() != RtpPacketMediaType::kRetransmission) {
if (last_sent_seq_.has_value()) {
RTC_DCHECK_EQ(static_cast<uint16_t>(*last_sent_seq_ + 1),
packet->SequenceNumber());
}
last_sent_seq_ = packet->SequenceNumber();
} else if (packet->Ssrc() == rtx_ssrc_) {
if (last_sent_rtx_seq_.has_value()) {
RTC_DCHECK_EQ(static_cast<uint16_t>(*last_sent_rtx_seq_ + 1),
packet->SequenceNumber());
}
last_sent_rtx_seq_ = packet->SequenceNumber();
}
RTC_DCHECK(packet->packet_type().has_value());
RTC_DCHECK(HasCorrectSsrc(*packet));
if (packet->packet_type() == RtpPacketMediaType::kRetransmission) {
RTC_DCHECK(packet->retransmitted_sequence_number().has_value());
}
const Timestamp now = clock_->CurrentTime();
#if BWE_TEST_LOGGING_COMPILE_TIME_ENABLE
BweTestLoggingPlot(now, packet->Ssrc());
#endif
if (need_rtp_packet_infos_ &&
packet->packet_type() == RtpPacketToSend::Type::kVideo) {
// Last packet of a frame, add it to sequence number info map.
const uint32_t timestamp = packet->Timestamp() - timestamp_offset_;
rtp_sequence_number_map_->InsertPacket(
packet->SequenceNumber(),
RtpSequenceNumberMap::Info(
timestamp, packet->is_first_packet_of_frame(), packet->Marker()));
}
if (fec_generator_ && packet->fec_protect_packet()) {
// This packet should be protected by FEC, add it to packet generator.
RTC_DCHECK(fec_generator_);
RTC_DCHECK(packet->packet_type() == RtpPacketMediaType::kVideo);
absl::optional<std::pair<FecProtectionParams, FecProtectionParams>>
new_fec_params;
new_fec_params.swap(pending_fec_params_);
if (new_fec_params) {
fec_generator_->SetProtectionParameters(new_fec_params->first,
new_fec_params->second);
}
if (packet->is_red()) {
RtpPacketToSend unpacked_packet(*packet);
const rtc::CopyOnWriteBuffer buffer = packet->Buffer();
// Grab media payload type from RED header.
const size_t headers_size = packet->headers_size();
unpacked_packet.SetPayloadType(buffer[headers_size]);
// Copy the media payload into the unpacked buffer.
uint8_t* payload_buffer =
unpacked_packet.SetPayloadSize(packet->payload_size() - 1);
std::copy(&packet->payload()[0] + 1,
&packet->payload()[0] + packet->payload_size(), payload_buffer);
fec_generator_->AddPacketAndGenerateFec(unpacked_packet);
} else {
// If not RED encapsulated - we can just insert packet directly.
fec_generator_->AddPacketAndGenerateFec(*packet);
}
}
// Bug webrtc:7859. While FEC is invoked from rtp_sender_video, and not after
// the pacer, these modifications of the header below are happening after the
// FEC protection packets are calculated. This will corrupt recovered packets
// at the same place. It's not an issue for extensions, which are present in
// all the packets (their content just may be incorrect on recovered packets).
// In case of VideoTimingExtension, since it's present not in every packet,
// data after rtp header may be corrupted if these packets are protected by
// the FEC.
if (packet->HasExtension<TransmissionOffset>() &&
packet->capture_time() > Timestamp::Zero()) {
TimeDelta diff = now - packet->capture_time();
packet->SetExtension<TransmissionOffset>(kTimestampTicksPerMs * diff.ms());
}
if (packet->HasExtension<AbsoluteSendTime>()) {
packet->SetExtension<AbsoluteSendTime>(AbsoluteSendTime::To24Bits(now));
}
if (packet->HasExtension<VideoTimingExtension>()) {
if (populate_network2_timestamp_) {
packet->set_network2_time(now);
} else {
packet->set_pacer_exit_time(now);
}
}
auto compound_packet = Packet{std::move(packet), pacing_info, now};
if (enable_send_packet_batching_ && !is_audio_) {
packets_to_send_.push_back(std::move(compound_packet));
} else {
CompleteSendPacket(compound_packet, false);
}
}
void RtpSenderEgress::OnBatchComplete() {
RTC_DCHECK_RUN_ON(worker_queue_);
for (auto& packet : packets_to_send_) {
CompleteSendPacket(packet, &packet == &packets_to_send_.back());
}
packets_to_send_.clear();
}
void RtpSenderEgress::CompleteSendPacket(const Packet& compound_packet,
bool last_in_batch) {
RTC_DCHECK_RUN_ON(worker_queue_);
auto& [packet, pacing_info, now] = compound_packet;
const bool is_media = packet->packet_type() == RtpPacketMediaType::kAudio ||
packet->packet_type() == RtpPacketMediaType::kVideo;
PacketOptions options;
options.included_in_allocation = force_part_of_allocation_;
// Downstream code actually uses this flag to distinguish between media and
// everything else.
options.is_retransmit = !is_media;
if (auto packet_id = packet->GetExtension<TransportSequenceNumber>()) {
options.packet_id = *packet_id;
options.included_in_feedback = true;
options.included_in_allocation = true;
AddPacketToTransportFeedback(*packet_id, *packet, pacing_info);
}
options.additional_data = packet->additional_data();
const uint32_t packet_ssrc = packet->Ssrc();
if (packet->packet_type() != RtpPacketMediaType::kPadding &&
packet->packet_type() != RtpPacketMediaType::kRetransmission) {
UpdateDelayStatistics(packet->capture_time(), now, packet_ssrc);
UpdateOnSendPacket(options.packet_id, packet->capture_time(), packet_ssrc);
}
options.batchable = enable_send_packet_batching_ && !is_audio_;
options.last_packet_in_batch = last_in_batch;
const bool send_success = SendPacketToNetwork(*packet, options, pacing_info);
// Put packet in retransmission history or update pending status even if
// actual sending fails.
if (is_media && packet->allow_retransmission()) {
packet_history_->PutRtpPacket(std::make_unique<RtpPacketToSend>(*packet),
now);
} else if (packet->retransmitted_sequence_number()) {
packet_history_->MarkPacketAsSent(*packet->retransmitted_sequence_number());
}
if (send_success) {
// `media_has_been_sent_` is used by RTPSender to figure out if it can send
// padding in the absence of transport-cc or abs-send-time.
// In those cases media must be sent first to set a reference timestamp.
media_has_been_sent_ = true;
// TODO(sprang): Add support for FEC protecting all header extensions, add
// media packet to generator here instead.
RTC_DCHECK(packet->packet_type().has_value());
RtpPacketMediaType packet_type = *packet->packet_type();
RtpPacketCounter counter(*packet);
size_t size = packet->size();
UpdateRtpStats(now, packet_ssrc, packet_type, std::move(counter), size);
}
}
RtpSendRates RtpSenderEgress::GetSendRates(Timestamp now) const {
RTC_DCHECK_RUN_ON(worker_queue_);
RtpSendRates current_rates;
for (size_t i = 0; i < kNumMediaTypes; ++i) {
RtpPacketMediaType type = static_cast<RtpPacketMediaType>(i);
current_rates[type] =
DataRate::BitsPerSec(send_rates_[i].Rate(now.ms()).value_or(0));
}
return current_rates;
}
void RtpSenderEgress::GetDataCounters(StreamDataCounters* rtp_stats,
StreamDataCounters* rtx_stats) const {
RTC_DCHECK_RUN_ON(worker_queue_);
*rtp_stats = rtp_stats_;
*rtx_stats = rtx_rtp_stats_;
}
void RtpSenderEgress::ForceIncludeSendPacketsInAllocation(
bool part_of_allocation) {
RTC_DCHECK_RUN_ON(worker_queue_);
force_part_of_allocation_ = part_of_allocation;
}
bool RtpSenderEgress::MediaHasBeenSent() const {
RTC_DCHECK_RUN_ON(worker_queue_);
return media_has_been_sent_;
}
void RtpSenderEgress::SetMediaHasBeenSent(bool media_sent) {
RTC_DCHECK_RUN_ON(worker_queue_);
media_has_been_sent_ = media_sent;
}
void RtpSenderEgress::SetTimestampOffset(uint32_t timestamp) {
RTC_DCHECK_RUN_ON(worker_queue_);
timestamp_offset_ = timestamp;
}
std::vector<RtpSequenceNumberMap::Info> RtpSenderEgress::GetSentRtpPacketInfos(
rtc::ArrayView<const uint16_t> sequence_numbers) const {
RTC_DCHECK_RUN_ON(worker_queue_);
RTC_DCHECK(!sequence_numbers.empty());
if (!need_rtp_packet_infos_) {
return std::vector<RtpSequenceNumberMap::Info>();
}
std::vector<RtpSequenceNumberMap::Info> results;
results.reserve(sequence_numbers.size());
for (uint16_t sequence_number : sequence_numbers) {
const auto& info = rtp_sequence_number_map_->Get(sequence_number);
if (!info) {
// The empty vector will be returned. We can delay the clearing
// of the vector until after we exit the critical section.
return std::vector<RtpSequenceNumberMap::Info>();
}
results.push_back(*info);
}
return results;
}
void RtpSenderEgress::SetFecProtectionParameters(
const FecProtectionParams& delta_params,
const FecProtectionParams& key_params) {
RTC_DCHECK_RUN_ON(worker_queue_);
pending_fec_params_.emplace(delta_params, key_params);
}
std::vector<std::unique_ptr<RtpPacketToSend>>
RtpSenderEgress::FetchFecPackets() {
RTC_DCHECK_RUN_ON(worker_queue_);
if (fec_generator_) {
return fec_generator_->GetFecPackets();
}
return {};
}
void RtpSenderEgress::OnAbortedRetransmissions(
rtc::ArrayView<const uint16_t> sequence_numbers) {
RTC_DCHECK_RUN_ON(worker_queue_);
// Mark aborted retransmissions as sent, rather than leaving them in
// a 'pending' state - otherwise they can not be requested again and
// will not be cleared until the history has reached its max size.
for (uint16_t seq_no : sequence_numbers) {
packet_history_->MarkPacketAsSent(seq_no);
}
}
bool RtpSenderEgress::HasCorrectSsrc(const RtpPacketToSend& packet) const {
switch (*packet.packet_type()) {
case RtpPacketMediaType::kAudio:
case RtpPacketMediaType::kVideo:
return packet.Ssrc() == ssrc_;
case RtpPacketMediaType::kRetransmission:
case RtpPacketMediaType::kPadding:
// Both padding and retransmission must be on either the media or the
// RTX stream.
return packet.Ssrc() == rtx_ssrc_ || packet.Ssrc() == ssrc_;
case RtpPacketMediaType::kForwardErrorCorrection:
// FlexFEC is on separate SSRC, ULPFEC uses media SSRC.
return packet.Ssrc() == ssrc_ || packet.Ssrc() == flexfec_ssrc_;
}
return false;
}
void RtpSenderEgress::AddPacketToTransportFeedback(
uint16_t packet_id,
const RtpPacketToSend& packet,
const PacedPacketInfo& pacing_info) {
if (transport_feedback_observer_) {
RtpPacketSendInfo packet_info;
packet_info.transport_sequence_number = packet_id;
packet_info.rtp_timestamp = packet.Timestamp();
packet_info.length = packet.size();
packet_info.pacing_info = pacing_info;
packet_info.packet_type = packet.packet_type();
switch (*packet_info.packet_type) {
case RtpPacketMediaType::kAudio:
case RtpPacketMediaType::kVideo:
packet_info.media_ssrc = ssrc_;
packet_info.rtp_sequence_number = packet.SequenceNumber();
break;
case RtpPacketMediaType::kRetransmission:
// For retransmissions, we're want to remove the original media packet
// if the retransmit arrives - so populate that in the packet info.
packet_info.media_ssrc = ssrc_;
packet_info.rtp_sequence_number =
*packet.retransmitted_sequence_number();
break;
case RtpPacketMediaType::kPadding:
case RtpPacketMediaType::kForwardErrorCorrection:
// We're not interested in feedback about these packets being received
// or lost.
break;
}
transport_feedback_observer_->OnAddPacket(packet_info);
}
}
void RtpSenderEgress::UpdateDelayStatistics(Timestamp capture_time,
Timestamp now,
uint32_t ssrc) {
RTC_DCHECK_RUN_ON(worker_queue_);
if (!send_side_delay_observer_ || capture_time.IsInfinite())
return;
TimeDelta avg_delay = TimeDelta::Zero();
TimeDelta max_delay = TimeDelta::Zero();
{
// Compute the max and average of the recent capture-to-send delays.
// The time complexity of the current approach depends on the distribution
// of the delay values. This could be done more efficiently.
// Remove elements older than kSendSideDelayWindowMs.
auto lower_bound = send_delays_.lower_bound(now - kSendSideDelayWindow);
for (auto it = send_delays_.begin(); it != lower_bound; ++it) {
if (max_delay_it_ == it) {
max_delay_it_ = send_delays_.end();
}
sum_delays_ -= it->second;
}
send_delays_.erase(send_delays_.begin(), lower_bound);
if (max_delay_it_ == send_delays_.end()) {
// Removed the previous max. Need to recompute.
RecomputeMaxSendDelay();
}
// Add the new element.
TimeDelta new_send_delay = now - capture_time;
auto [it, inserted] = send_delays_.emplace(now, new_send_delay);
if (!inserted) {
// TODO(terelius): If we have multiple delay measurements during the same
// millisecond then we keep the most recent one. It is not clear that this
// is the right decision, but it preserves an earlier behavior.
TimeDelta previous_send_delay = it->second;
sum_delays_ -= previous_send_delay;
it->second = new_send_delay;
if (max_delay_it_ == it && new_send_delay < previous_send_delay) {
RecomputeMaxSendDelay();
}
}
if (max_delay_it_ == send_delays_.end() ||
it->second >= max_delay_it_->second) {
max_delay_it_ = it;
}
sum_delays_ += new_send_delay;
size_t num_delays = send_delays_.size();
RTC_DCHECK(max_delay_it_ != send_delays_.end());
max_delay = max_delay_it_->second;
avg_delay = sum_delays_ / num_delays;
}
send_side_delay_observer_->SendSideDelayUpdated(avg_delay.ms(),
max_delay.ms(), ssrc);
}
void RtpSenderEgress::RecomputeMaxSendDelay() {
RTC_DCHECK_RUN_ON(worker_queue_);
max_delay_it_ = send_delays_.begin();
for (auto it = send_delays_.begin(); it != send_delays_.end(); ++it) {
if (it->second >= max_delay_it_->second) {
max_delay_it_ = it;
}
}
}
void RtpSenderEgress::UpdateOnSendPacket(int packet_id,
Timestamp capture_time,
uint32_t ssrc) {
if (!send_packet_observer_ || capture_time.IsInfinite() || packet_id == -1) {
return;
}
send_packet_observer_->OnSendPacket(packet_id, capture_time.ms(), ssrc);
}
bool RtpSenderEgress::SendPacketToNetwork(const RtpPacketToSend& packet,
const PacketOptions& options,
const PacedPacketInfo& pacing_info) {
RTC_DCHECK_RUN_ON(worker_queue_);
int bytes_sent = -1;
if (transport_) {
bytes_sent = transport_->SendRtp(packet.data(), packet.size(), options)
? static_cast<int>(packet.size())
: -1;
if (event_log_ && bytes_sent > 0) {
event_log_->Log(std::make_unique<RtcEventRtpPacketOutgoing>(
packet, pacing_info.probe_cluster_id));
}
}
if (bytes_sent <= 0) {
RTC_LOG(LS_WARNING) << "Transport failed to send packet.";
return false;
}
return true;
}
void RtpSenderEgress::UpdateRtpStats(Timestamp now,
uint32_t packet_ssrc,
RtpPacketMediaType packet_type,
RtpPacketCounter counter,
size_t packet_size) {
RTC_DCHECK_RUN_ON(worker_queue_);
// TODO(bugs.webrtc.org/11581): send_rates_ should be touched only on the
// worker thread.
RtpSendRates send_rates;
StreamDataCounters* counters =
packet_ssrc == rtx_ssrc_ ? &rtx_rtp_stats_ : &rtp_stats_;
counters->MaybeSetFirstPacketTime(now);
if (packet_type == RtpPacketMediaType::kForwardErrorCorrection) {
counters->fec.Add(counter);
} else if (packet_type == RtpPacketMediaType::kRetransmission) {
counters->retransmitted.Add(counter);
}
counters->transmitted.Add(counter);
send_rates_[static_cast<size_t>(packet_type)].Update(packet_size, now.ms());
if (bitrate_callback_) {
send_rates = GetSendRates(now);
}
if (rtp_stats_callback_) {
rtp_stats_callback_->DataCountersUpdated(*counters, packet_ssrc);
}
// The bitrate_callback_ and rtp_stats_callback_ pointers in practice point
// to the same object, so these callbacks could be consolidated into one.
if (bitrate_callback_) {
bitrate_callback_->Notify(
send_rates.Sum().bps(),
send_rates[RtpPacketMediaType::kRetransmission].bps(), ssrc_);
}
}
void RtpSenderEgress::PeriodicUpdate() {
RTC_DCHECK_RUN_ON(worker_queue_);
RTC_DCHECK(bitrate_callback_);
RtpSendRates send_rates = GetSendRates(clock_->CurrentTime());
bitrate_callback_->Notify(
send_rates.Sum().bps(),
send_rates[RtpPacketMediaType::kRetransmission].bps(), ssrc_);
}
#if BWE_TEST_LOGGING_COMPILE_TIME_ENABLE
void RtpSenderEgress::BweTestLoggingPlot(Timestamp now, uint32_t packet_ssrc) {
RTC_DCHECK_RUN_ON(worker_queue_);
const auto rates = GetSendRates(now);
if (is_audio_) {
BWE_TEST_LOGGING_PLOT_WITH_SSRC(1, "AudioTotBitrate_kbps", now.ms(),
rates.Sum().kbps(), packet_ssrc);
BWE_TEST_LOGGING_PLOT_WITH_SSRC(
1, "AudioNackBitrate_kbps", now.ms(),
rates[RtpPacketMediaType::kRetransmission].kbps(), packet_ssrc);
} else {
BWE_TEST_LOGGING_PLOT_WITH_SSRC(1, "VideoTotBitrate_kbps", now.ms(),
rates.Sum().kbps(), packet_ssrc);
BWE_TEST_LOGGING_PLOT_WITH_SSRC(
1, "VideoNackBitrate_kbps", now.ms(),
rates[RtpPacketMediaType::kRetransmission].kbps(), packet_ssrc);
}
}
#endif // BWE_TEST_LOGGING_COMPILE_TIME_ENABLE
} // namespace webrtc