Notfiy NQE of QUIC RTT

net/quic/quic_connection_logger.cc

Index: net/quic/quic_connection_logger.cc
diff --git a/net/quic/quic_connection_logger.cc b/net/quic/quic_connection_logger.cc
index c0eb82c68e5be162b63be4606af284ca2708d4df..a0c4c76cee8604f4396a421a2a47bdb51cb0c598 100644
--- a/net/quic/quic_connection_logger.cc
+++ b/net/quic/quic_connection_logger.cc
@@ -21,6 +21,7 @@
 #include "net/quic/crypto/crypto_handshake_message.h"
 #include "net/quic/crypto/crypto_protocol.h"
 #include "net/quic/quic_address_mismatch.h"
+#include "net/quic/quic_sent_packet_manager.h"
 #include "net/quic/quic_socket_address_coder.h"
 
 using base::StringPiece;
@@ -289,7 +290,9 @@ AddressFamily GetRealAddressFamily(const IPAddressNumber& address) {
 QuicConnectionLogger::QuicConnectionLogger(
     QuicSpdySession* session,
     const char* const connection_description,
-    const BoundNetLog& net_log)
+    const BoundNetLog& net_log,
+    QuicConnection* connection,
+    scoped_ptr<SocketPerformanceWatcher> socket_performance_watcher)
     : net_log_(net_log),
       session_(session),
       last_received_packet_number_(0),
@@ -309,7 +312,9 @@ QuicConnectionLogger::QuicConnectionLogger(
       num_duplicate_packets_(0),
       num_blocked_frames_received_(0),
       num_blocked_frames_sent_(0),
-      connection_description_(connection_description) {}
+      connection_description_(connection_description),
+      connection_(connection),
+      socket_performance_watcher_(socket_performance_watcher.Pass()) {}
 
 QuicConnectionLogger::~QuicConnectionLogger() {
   UMA_HISTOGRAM_COUNTS("Net.QuicSession.OutOfOrderPacketsReceived",
@@ -459,6 +464,14 @@ void QuicConnectionLogger::OnPacketSent(
         base::Bind(&NetLogQuicPacketRetransmittedCallback,
                    original_packet_number, serialized_packet.packet_number));
   }
+  // Notify socket performance watcher of the updated RTT value.
+  if (socket_performance_watcher_ && connection_) {

[Ryan Hamilton, 2015/09/17 01:59:49]

Why would we not have a connection?

[tbansal1, 2015/09/17 22:23:42]

Removed, I was just not sure, so tried to be on the safer side.

+    socket_performance_watcher_->OnUpdatedRTTAvailable(
+        base::TimeDelta::FromMicroseconds(connection_->sent_packet_manager()
+                                              .GetRttStats()
+                                              ->smoothed_rtt()
+                                              .ToMicroseconds()));
+  }
 }
 
 void QuicConnectionLogger::OnPacketReceived(const IPEndPoint& self_address,
@@ -477,6 +490,15 @@ void QuicConnectionLogger::OnPacketReceived(const IPEndPoint& self_address,
       NetLog::TYPE_QUIC_SESSION_PACKET_RECEIVED,
       base::Bind(&NetLogQuicPacketCallback, &self_address, &peer_address,
                  packet.length()));
+
+  // Notify socket performance watcher of the updated RTT value.
+  if (socket_performance_watcher_ && connection_) {
+    socket_performance_watcher_->OnUpdatedRTTAvailable(
+        base::TimeDelta::FromMicroseconds(connection_->sent_packet_manager()
+                                              .GetRttStats()
+                                              ->smoothed_rtt()
+                                              .ToMicroseconds()));
+  }

[Ryan Hamilton, 2015/09/17 01:59:49]

I think smoothed_rtt() can return Zero. Is that OK?

[tbansal1, 2015/09/17 22:23:42]

Added check for zero.

 }

[Ryan Hamilton, 2015/09/17 01:59:49]

Looking at this more closely, I see that you're re-fetching RTT on every packet
sent and received. I wonder if it might be a better idea to do this only when
the RTT changes. To do this, I propose you add a new method to
QuicConnectionDebugVisitorInterface:

void OnRttChanged(QuicTime::Delta rtt) {}

You can then call this method from:

https://code.google.com/p/chromium/codesearch#chromium/src/net/quic/quic_conn...

And then implement it in QuicConnectionLogger to do the logic you have here.

Does that sound workable?  Looks good otherwise...

[tbansal1, 2015/09/17 22:23:42]

Done. That's much cleaner :)

 
 void QuicConnectionLogger::OnUnauthenticatedHeader(