Add GoogCCScenario test of WebRTC-Bwe-ResetOnAdapterIdChange

The test tests that a route change does not cause BWE do drop unless the adapter is changed.

Bug: webrtc:42221538
Change-Id: I49be55172aff285c55d2564ec3389f3fc7c01d62
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/350820
Reviewed-by: Jonas Oreland <jonaso@webrtc.org>
Reviewed-by: Jonas Oreland <jonaso@google.com>
Commit-Queue: Per Kjellander <perkj@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#42347}

modules/congestion_controller/goog_cc/goog_cc_network_control_unittest.cc

@@ -799,6 +799,44 @@ TEST(GoogCcScenario, MaintainsLowRateInSafeResetTrial) {
   EXPECT_NEAR(client->send_bandwidth().kbps(), kLinkCapacity.kbps(), 50);
 }
 
+TEST(GoogCcScenario, DoNotResetBweUnlessNetworkAdapterChangeOnRoutChange) {
+  ScopedFieldTrials trial("WebRTC-Bwe-ResetOnAdapterIdChange/Enabled/");
+  Scenario s("googcc_unit/do_not_reset_bwe_unless_adapter_change");
+
+  const DataRate kLinkCapacity = DataRate::KilobitsPerSec(1000);
+  const DataRate kStartRate = DataRate::KilobitsPerSec(300);
+
+  auto send_net = s.CreateSimulationNode([&](NetworkSimulationConfig* c) {
+    c->bandwidth = kLinkCapacity;
+    c->delay = TimeDelta::Millis(50);
+  });
+  auto* client = s.CreateClient("send", [&](CallClientConfig* c) {
+    c->transport.rates.start_rate = kStartRate;
+  });
+  client->UpdateNetworkAdapterId(0);
+  auto* route = s.CreateRoutes(
+      client, {send_net}, s.CreateClient("return", CallClientConfig()),
+      {s.CreateSimulationNode(NetworkSimulationConfig())});
+  s.CreateVideoStream(route->forward(), VideoStreamConfig());
+  // Allow the controller to stabilize.
+  s.RunFor(TimeDelta::Millis(500));
+  EXPECT_NEAR(client->send_bandwidth().kbps(), kLinkCapacity.kbps(), 300);
+  s.ChangeRoute(route->forward(), {send_net});
+  // Allow new settings to propagate.
+  s.RunFor(TimeDelta::Millis(50));
+  // Under the trial, the target should not drop.
+  EXPECT_NEAR(client->send_bandwidth().kbps(), kLinkCapacity.kbps(), 300);
+
+  s.RunFor(TimeDelta::Millis(500));
+  // But if adapter id change, BWE should reset and start from the beginning if
+  // the network route changes.
+  client->UpdateNetworkAdapterId(1);
+  s.ChangeRoute(route->forward(), {send_net});
+  // Allow new settings to propagate.
+  s.RunFor(TimeDelta::Millis(50));
+  EXPECT_NEAR(client->send_bandwidth().kbps(), kStartRate.kbps(), 30);
+}
+
 TEST(GoogCcScenario, CutsHighRateInSafeResetTrial) {
   const DataRate kLinkCapacity = DataRate::KilobitsPerSec(1000);
   const DataRate kStartRate = DataRate::KilobitsPerSec(300);
@@ -819,6 +857,7 @@ TEST(GoogCcScenario, CutsHighRateInSafeResetTrial) {
   // Allow the controller to stabilize.
   s.RunFor(TimeDelta::Millis(500));
   EXPECT_NEAR(client->send_bandwidth().kbps(), kLinkCapacity.kbps(), 300);
+  client->UpdateNetworkAdapterId(1);
   s.ChangeRoute(route->forward(), {send_net});
   // Allow new settings to propagate.
   s.RunFor(TimeDelta::Millis(50));
@@ -851,6 +890,7 @@ TEST(GoogCcScenario, DetectsHighRateInSafeResetTrial) {
   // Allow the controller to stabilize.
   s.RunFor(TimeDelta::Millis(2000));
   EXPECT_NEAR(client->send_bandwidth().kbps(), kInitialLinkCapacity.kbps(), 50);
+  client->UpdateNetworkAdapterId(1);
   s.ChangeRoute(route->forward(), {new_net});
   // Allow new settings to propagate, but not probes to be received.
   s.RunFor(TimeDelta::Millis(50));

test/scenario/call_client.cc

@@ -364,6 +364,10 @@ void CallClient::SendTask(std::function<void()> task) {
   task_queue_.SendTask(std::move(task));
 }
 
+void CallClient::UpdateNetworkAdapterId(int adapter_id) {
+  transport_->UpdateAdapterId(adapter_id);
+}
+
 int16_t CallClient::Bind(EmulatedEndpoint* endpoint) {
   uint16_t port = endpoint->BindReceiver(0, this).value();
   endpoints_.push_back({endpoint, port});

test/scenario/call_client.h

@@ -130,6 +130,9 @@ class CallClient : public EmulatedNetworkReceiverInterface {
   void SetVideoReceiveRtpHeaderExtensions(
       rtc::ArrayView<RtpExtension> extensions);
 
+  // Sets the network adapter id used next time the network route changes.
+  void UpdateNetworkAdapterId(int adapter_id);
+
   void OnPacketReceived(EmulatedIpPacket packet) override;
   std::unique_ptr<RtcEventLogOutput> GetLogWriter(std::string name);
 

test/scenario/network_node.cc

@@ -14,6 +14,7 @@
 #include <vector>
 
 #include "absl/cleanup/cleanup.h"
+#include "api/sequence_checker.h"
 #include "rtc_base/net_helper.h"
 #include "rtc_base/numerics/safe_minmax.h"
 
@@ -33,6 +34,12 @@ SimulatedNetwork::Config CreateSimulationConfig(
       config.packet_queue_length_limit.value_or(0);
   return sim_config;
 }
+
+rtc::RouteEndpoint CreateRouteEndpoint(uint16_t network_id,
+                                       uint16_t adapter_id) {
+  return rtc::RouteEndpoint(rtc::ADAPTER_TYPE_UNKNOWN, adapter_id, network_id,
+                            /* uses_turn = */ false);
+}
 }  // namespace
 
 SimulationNode::SimulationNode(NetworkSimulationConfig config,
@@ -68,7 +75,9 @@ ColumnPrinter SimulationNode::ConfigPrinter() const {
 
 NetworkNodeTransport::NetworkNodeTransport(Clock* sender_clock,
                                            Call* sender_call)
-    : sender_clock_(sender_clock), sender_call_(sender_call) {}
+    : sender_clock_(sender_clock), sender_call_(sender_call) {
+  sequence_checker_.Detach();
+}
 
 NetworkNodeTransport::~NetworkNodeTransport() = default;
 
@@ -103,16 +112,26 @@ bool NetworkNodeTransport::SendRtcp(rtc::ArrayView<const uint8_t> packet) {
   return true;
 }
 
+void NetworkNodeTransport::UpdateAdapterId(int adapter_id) {
+  RTC_DCHECK_RUN_ON(&sequence_checker_);
+  adapter_id_ = adapter_id;
+}
+
 void NetworkNodeTransport::Connect(EmulatedEndpoint* endpoint,
                                    const rtc::SocketAddress& receiver_address,
                                    DataSize packet_overhead) {
+  RTC_DCHECK_RUN_ON(&sequence_checker_);
   rtc::NetworkRoute route;
   route.connected = true;
   // We assume that the address will be unique in the lower bytes.
-  route.local = rtc::RouteEndpoint::CreateWithNetworkId(static_cast<uint16_t>(
-      receiver_address.ipaddr().v4AddressAsHostOrderInteger()));
-  route.remote = rtc::RouteEndpoint::CreateWithNetworkId(static_cast<uint16_t>(
-      receiver_address.ipaddr().v4AddressAsHostOrderInteger()));
+  route.local = CreateRouteEndpoint(
+      static_cast<uint16_t>(
+          receiver_address.ipaddr().v4AddressAsHostOrderInteger()),
+      adapter_id_);
+  route.remote = CreateRouteEndpoint(
+      static_cast<uint16_t>(
+          receiver_address.ipaddr().v4AddressAsHostOrderInteger()),
+      adapter_id_);
   route.packet_overhead = packet_overhead.bytes() +
                           receiver_address.ipaddr().overhead() +
                           cricket::kUdpHeaderSize;

test/scenario/network_node.h

@@ -17,6 +17,7 @@
 #include <vector>
 
 #include "api/call/transport.h"
+#include "api/sequence_checker.h"
 #include "api/units/timestamp.h"
 #include "call/call.h"
 #include "rtc_base/copy_on_write_buffer.h"
@@ -53,6 +54,8 @@ class NetworkNodeTransport : public Transport {
   NetworkNodeTransport(Clock* sender_clock, Call* sender_call);
   ~NetworkNodeTransport() override;
 
+  void UpdateAdapterId(int adapter_id);
+
   bool SendRtp(rtc::ArrayView<const uint8_t> packet,
                const PacketOptions& options) override;
   bool SendRtcp(rtc::ArrayView<const uint8_t> packet) override;
@@ -68,6 +71,9 @@ class NetworkNodeTransport : public Transport {
   }
 
  private:
+  SequenceChecker sequence_checker_;
+  int adapter_id_ RTC_GUARDED_BY(sequence_checker_) = 0;
+
   Mutex mutex_;
   Clock* const sender_clock_;
   Call* const sender_call_;