Add quic stats for d6d events

Summary: This increases visibility over d6d lifecycle.

Reviewed By: avasylev

Differential Revision: D24026410

fbshipit-source-id: ee382a5fb60e48d4ee441ad760251673a10c85da

quic/d6d/QuicD6DStateFunctions.cpp

@@ -24,6 +24,9 @@ static TimePoint reportUpperBound(QuicConnectionStateBase& conn) {
   auto& d6d = conn.d6d;
   const auto lastProbeSize = d6d.lastProbe->packetSize;
   const auto now = Clock::now();
+
+  QUIC_STATS(
+      conn.statsCallback, onConnectionPMTUUpperBoundDetected, lastProbeSize);
   if (conn.instrumentationObservers_.size() > 0) {
     InstrumentationObserver::PMTUUpperBoundEvent upperBoundEvent(
         now,
@@ -51,6 +54,10 @@ static TimePoint reportUpperBound(QuicConnectionStateBase& conn) {
 static TimePoint reportBlackhole(
     QuicConnectionStateBase& conn,
     const OutstandingPacket& packet) {
+  QUIC_STATS(
+      conn.statsCallback,
+      onConnectionPMTUBlackholeDetected,
+      packet.metadata.encodedSize);
   auto& d6d = conn.d6d;
   const auto now = Clock::now();
   if (conn.instrumentationObservers_.size() > 0) {
@@ -117,6 +124,7 @@ void onD6DLastProbeAcked(QuicConnectionStateBase& conn) {
         LOG(ERROR) << "D6D lastProbeSize <= udpSendPacketLen";
         return;
       }
+      QUIC_STATS(conn.statsCallback, onConnectionPMTURaised);
       conn.udpSendPacketLen = lastProbeSize;
       if (maybeNextProbeSize.hasValue() &&
           *maybeNextProbeSize > conn.udpSendPacketLen &&

quic/samples/echo/LogQuicStats.h

@@ -149,6 +149,26 @@ class LogQuicStats : public quic::QuicTransportStatsCallback {
             << "onUDPSocketWriteError errorType=" << toString(errorType);
   }
 
+  void onConnectionD6DStarted() override {
+    VLOG(2) << prefix_ << "onConnectionD6DStarted";
+  }
+
+  void onConnectionPMTURaised() override {
+    VLOG(2) << prefix_ << "onConnectionPMTURaised";
+  }
+
+  void onConnectionPMTUBlackholeDetected(
+      uint64_t pmtuAtBlackholeTime) override {
+    VLOG(2) << prefix_
+            << "onConnectionPMTUBlackholeDetected pmtuAtBlackholeTime="
+            << pmtuAtBlackholeTime;
+  }
+
+  void onConnectionPMTUUpperBoundDetected(uint64_t pmtuUpperBound) override {
+    VLOG(2) << prefix_ << "onConnectionPMTUUpperBoundDetected pmtuUpperBound="
+            << pmtuUpperBound;
+  }
+
  private:
   std::string prefix_;
 };

quic/server/QuicServerTransport.cpp

@@ -536,6 +536,7 @@ void QuicServerTransport::maybeStartD6DProbing() {
     // connections, for which probing is relatively expensive and less
     // valuable
     conn_->pendingEvents.d6d.sendProbeDelay = kDefaultD6DKickStartDelay;
+    QUIC_STATS(conn_->statsCallback, onConnectionD6DStarted);
   }
 }
 

quic/state/QuicTransportStatsCallback.h

@@ -136,6 +136,15 @@ class QuicTransportStatsCallback {
 
   virtual void onUDPSocketWriteError(SocketErrorType errorType) = 0;
 
+  virtual void onConnectionD6DStarted() = 0;
+
+  virtual void onConnectionPMTURaised() = 0;
+
+  virtual void onConnectionPMTUBlackholeDetected(
+      uint64_t pmtuAtBlackholeTime) = 0;
+
+  virtual void onConnectionPMTUUpperBoundDetected(uint64_t pmtuUpperBound) = 0;
+
   static const char* toString(ConnectionCloseReason reason) {
     switch (reason) {
       case ConnectionCloseReason::NONE:

quic/state/test/MockQuicStats.h

@@ -47,6 +47,10 @@ class MockQuicStats : public QuicTransportStatsCallback {
   MOCK_METHOD1(onRead, void(size_t));
   MOCK_METHOD1(onWrite, void(size_t));
   MOCK_METHOD1(onUDPSocketWriteError, void(SocketErrorType));
+  MOCK_METHOD0(onConnectionD6DStarted, void());
+  MOCK_METHOD0(onConnectionPMTURaised, void());
+  MOCK_METHOD1(onConnectionPMTUBlackholeDetected, void(uint64_t));
+  MOCK_METHOD1(onConnectionPMTUUpperBoundDetected, void(uint64_t));
 };
 
 class MockQuicStatsFactory : public QuicTransportStatsCallbackFactory {