Refactor of QUIC's rtt storage and calculation to have a single RttStats

net/quic/quic_sent_packet_manager_test.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/quic_sent_packet_manager.h"
 
 #include "base/stl_util.h"
 #include "net/quic/test_tools/quic_sent_packet_manager_peer.h"
 #include "net/quic/test_tools/quic_test_utils.h"
 #include "testing/gmock/include/gmock/gmock.h"
@@ skipping 17 matching lines @@
     // Disable tail loss probes for most tests.
     QuicSentPacketManagerPeer::SetMaxTailLossProbes(&manager_, 0);
     // Advance the time 1s so the send times are never QuicTime::Zero.
     clock_.AdvanceTime(QuicTime::Delta::FromMilliseconds(1000));
   }
 
   virtual ~QuicSentPacketManagerTest() {
     STLDeleteElements(&packets_);
   }
 
-  virtual void SetUp() {
-    // Ack handling requests a smoothed rtt for loss detection.
-    EXPECT_CALL(*send_algorithm_, SmoothedRtt())
-        .WillRepeatedly(Return(QuicTime::Delta::FromMilliseconds(1)));
-  }
-
   void VerifyUnackedPackets(QuicPacketSequenceNumber* packets,
                             size_t num_packets) {
     if (num_packets == 0) {
       EXPECT_FALSE(manager_.HasUnackedPackets());
       EXPECT_EQ(0u, QuicSentPacketManagerPeer::GetNumRetransmittablePackets(
           &manager_));
       return;
     }
 
     EXPECT_TRUE(manager_.HasUnackedPackets());
@@ skipping 151 matching lines @@
 TEST_F(QuicSentPacketManagerTest, RetransmitThenAck) {
   SendDataPacket(1);
   RetransmitAndSendPacket(1, 2);
 
   // Ack 2 but not 1.
   ReceivedPacketInfo received_info;
   received_info.largest_observed = 2;
   received_info.missing_packets.insert(1);
   EXPECT_CALL(*send_algorithm_, UpdateRtt(_));
   EXPECT_CALL(*send_algorithm_, OnPacketAcked(2, _)).Times(1);
-  manager_.OnIncomingAck(received_info, QuicTime::Zero());
+  manager_.OnIncomingAck(received_info, clock_.Now());
 
   // Packet 1 is unacked, pending, but not retransmittable.
   QuicPacketSequenceNumber unacked[] = { 1 };
   VerifyUnackedPackets(unacked, arraysize(unacked));
   EXPECT_TRUE(QuicSentPacketManagerPeer::HasPendingPackets(&manager_));
   VerifyRetransmittablePackets(NULL, 0);
 }
 
 TEST_F(QuicSentPacketManagerTest, RetransmitThenAckBeforeSend) {
   SendDataPacket(1);
   QuicSentPacketManagerPeer::MarkForRetransmission(
       &manager_, 1, NACK_RETRANSMISSION);
   EXPECT_TRUE(manager_.HasPendingRetransmissions());
 
   // Ack 1.
   ReceivedPacketInfo received_info;
   received_info.largest_observed = 1;
   EXPECT_CALL(*send_algorithm_, UpdateRtt(_));
   EXPECT_CALL(*send_algorithm_, OnPacketAcked(1, _)).Times(1);
-  manager_.OnIncomingAck(received_info, QuicTime::Zero());
+  manager_.OnIncomingAck(received_info, clock_.Now());
 
   // There should no longer be a pending retransmission.
   EXPECT_FALSE(manager_.HasPendingRetransmissions());
 
   // No unacked packets remain.
   VerifyUnackedPackets(NULL, 0);
   VerifyRetransmittablePackets(NULL, 0);
   EXPECT_EQ(0u, stats_.packets_spuriously_retransmitted);
 }
 
@@ skipping 212 matching lines @@
   ReceivedPacketInfo received_info;
   received_info.largest_observed = 4;
   received_info.missing_packets.insert(1);
   received_info.missing_packets.insert(2);
   received_info.missing_packets.insert(3);
   received_info.missing_packets.insert(4);
   received_info.is_truncated = true;
   EXPECT_CALL(*send_algorithm_, UpdateRtt(_));
   EXPECT_CALL(*send_algorithm_, OnPacketLost(1, _));
   EXPECT_CALL(*send_algorithm_, OnPacketAbandoned(1, _));
-  manager_.OnIncomingAck(received_info, QuicTime::Zero());
+  manager_.OnIncomingAck(received_info, clock_.Now());
 
   // High water mark will be raised.
   QuicPacketSequenceNumber unacked[] = { 2, 3, 4 };
   VerifyUnackedPackets(unacked, arraysize(unacked));
   QuicPacketSequenceNumber retransmittable[] = { 4 };
   VerifyRetransmittablePackets(retransmittable, arraysize(retransmittable));
 }
 
 TEST_F(QuicSentPacketManagerTest, AckPreviousTransmissionThenTruncatedAck) {
   SendDataPacket(1);
   RetransmitAndSendPacket(1, 2);
   RetransmitAndSendPacket(2, 3);
   RetransmitAndSendPacket(3, 4);
   manager_.OnSerializedPacket(CreateDataPacket(5));
   manager_.OnSerializedPacket(CreateDataPacket(6));
   manager_.OnSerializedPacket(CreateDataPacket(7));
   manager_.OnSerializedPacket(CreateDataPacket(8));
   manager_.OnSerializedPacket(CreateDataPacket(9));
 
   // Ack previous transmission
   {
     ReceivedPacketInfo received_info;
     received_info.largest_observed = 2;
     received_info.missing_packets.insert(1);
     EXPECT_CALL(*send_algorithm_, UpdateRtt(_));
     EXPECT_CALL(*send_algorithm_, OnPacketAcked(2, _));
-    manager_.OnIncomingAck(received_info, QuicTime::Zero());
+    manager_.OnIncomingAck(received_info, clock_.Now());
     EXPECT_TRUE(manager_.IsUnacked(4));
   }
 
   // Truncated ack with 4 NACKs
   {
     ReceivedPacketInfo received_info;
     received_info.largest_observed = 6;
     received_info.missing_packets.insert(3);
     received_info.missing_packets.insert(4);
     received_info.missing_packets.insert(5);
     received_info.missing_packets.insert(6);
     received_info.is_truncated = true;
     EXPECT_CALL(*send_algorithm_, OnPacketAcked(1, _));
     EXPECT_CALL(*send_algorithm_, OnPacketLost(3, _));
     EXPECT_CALL(*send_algorithm_, OnPacketAbandoned(3, _));
-    manager_.OnIncomingAck(received_info, QuicTime::Zero());
+    manager_.OnIncomingAck(received_info, clock_.Now());
   }
 
   // High water mark will be raised.
   QuicPacketSequenceNumber unacked[] = { 4, 5, 6, 7, 8, 9 };
   VerifyUnackedPackets(unacked, arraysize(unacked));
   QuicPacketSequenceNumber retransmittable[] = { 5, 6, 7, 8, 9 };
   VerifyRetransmittablePackets(retransmittable, arraysize(retransmittable));
 }
 
 TEST_F(QuicSentPacketManagerTest, GetLeastUnackedSentPacket) {
@@ skipping 40 matching lines @@
   QuicPacketSequenceNumber unacked[] = { 1, 2, 3 };
   VerifyUnackedPackets(unacked, arraysize(unacked));
   VerifyRetransmittablePackets(NULL, 0);
 
   manager_.DiscardUnackedPacket(1);
   EXPECT_EQ(2u, manager_.GetLeastUnackedSentPacket());
 
   // Ack 2.
   ReceivedPacketInfo received_info;
   received_info.largest_observed = 2;
-  manager_.OnIncomingAck(received_info, QuicTime::Zero());
+  manager_.OnIncomingAck(received_info, clock_.Now());
 
   EXPECT_EQ(3u, manager_.GetLeastUnackedSentPacket());
 
   // Discard the 3rd packet and ensure there are no FEC packets.
   manager_.DiscardUnackedPacket(3);
   EXPECT_FALSE(manager_.HasUnackedPackets());
 }
 
 TEST_F(QuicSentPacketManagerTest, GetSentTime) {
   VerifyUnackedPackets(NULL, 0);
@@ skipping 103 matching lines @@
   clock_.AdvanceTime(QuicTime::Delta::FromMilliseconds(20));
 
   EXPECT_CALL(*send_algorithm_, UpdateRtt(expected_rtt));
   EXPECT_CALL(*send_algorithm_,
               OnPacketAcked(sequence_number, _)).Times(1);
   ReceivedPacketInfo received_info;
   received_info.largest_observed = sequence_number;
   received_info.delta_time_largest_observed =
       QuicTime::Delta::FromMilliseconds(5);
   manager_.OnIncomingAck(received_info, clock_.Now());
-  EXPECT_EQ(expected_rtt, QuicSentPacketManagerPeer::rtt(&manager_));
+  EXPECT_EQ(expected_rtt,
+            QuicSentPacketManagerPeer::GetRttStats(&manager_)->latest_rtt());
 }
 
 TEST_F(QuicSentPacketManagerTest, RttWithInvalidDelta) {
   // Expect that the RTT is equal to the local time elapsed, since the
   // delta_time_largest_observed is larger than the local time elapsed
   // and is hence invalid.
   QuicPacketSequenceNumber sequence_number = 1;
   QuicTime::Delta expected_rtt = QuicTime::Delta::FromMilliseconds(10);
   SendDataPacket(sequence_number);
   clock_.AdvanceTime(expected_rtt);
 
   EXPECT_CALL(*send_algorithm_, UpdateRtt(expected_rtt));
   EXPECT_CALL(*send_algorithm_,
               OnPacketAcked(sequence_number, _)).Times(1);
   ReceivedPacketInfo received_info;
   received_info.largest_observed = sequence_number;
   received_info.delta_time_largest_observed =
       QuicTime::Delta::FromMilliseconds(11);
   manager_.OnIncomingAck(received_info, clock_.Now());
-  EXPECT_EQ(expected_rtt, QuicSentPacketManagerPeer::rtt(&manager_));
+  EXPECT_EQ(expected_rtt,
+            QuicSentPacketManagerPeer::GetRttStats(&manager_)->latest_rtt());
 }
 
 TEST_F(QuicSentPacketManagerTest, RttWithInfiniteDelta) {
   // Expect that the RTT is equal to the local time elapsed, since the
   // delta_time_largest_observed is infinite, and is hence invalid.
   QuicPacketSequenceNumber sequence_number = 1;
   QuicTime::Delta expected_rtt = QuicTime::Delta::FromMilliseconds(10);
   SendDataPacket(sequence_number);
   clock_.AdvanceTime(expected_rtt);
 
   EXPECT_CALL(*send_algorithm_, UpdateRtt(expected_rtt));
   EXPECT_CALL(*send_algorithm_,
               OnPacketAcked(sequence_number, _)).Times(1);
   ReceivedPacketInfo received_info;
   received_info.largest_observed = sequence_number;
   received_info.delta_time_largest_observed = QuicTime::Delta::Infinite();
   manager_.OnIncomingAck(received_info, clock_.Now());
-  EXPECT_EQ(expected_rtt, QuicSentPacketManagerPeer::rtt(&manager_));
+  EXPECT_EQ(expected_rtt,
+            QuicSentPacketManagerPeer::GetRttStats(&manager_)->latest_rtt());
 }
 
 TEST_F(QuicSentPacketManagerTest, RttZeroDelta) {
   // Expect that the RTT is the time between send and receive since the
   // delta_time_largest_observed is zero.
   QuicPacketSequenceNumber sequence_number = 1;
   QuicTime::Delta expected_rtt = QuicTime::Delta::FromMilliseconds(10);
   SendDataPacket(sequence_number);
   clock_.AdvanceTime(expected_rtt);
 
   EXPECT_CALL(*send_algorithm_, UpdateRtt(expected_rtt));
   EXPECT_CALL(*send_algorithm_, OnPacketAcked(sequence_number, _))
       .Times(1);
   ReceivedPacketInfo received_info;
   received_info.largest_observed = sequence_number;
   received_info.delta_time_largest_observed = QuicTime::Delta::Zero();
   manager_.OnIncomingAck(received_info, clock_.Now());
-  EXPECT_EQ(expected_rtt, QuicSentPacketManagerPeer::rtt(&manager_));
+  EXPECT_EQ(expected_rtt,
+            QuicSentPacketManagerPeer::GetRttStats(&manager_)->latest_rtt());
 }
 
 TEST_F(QuicSentPacketManagerTest, TailLossProbeTimeout) {
   QuicSentPacketManagerPeer::SetMaxTailLossProbes(&manager_, 2);
 
   // Send 1 packet.
   QuicPacketSequenceNumber sequence_number = 1;
   SendDataPacket(sequence_number);
 
   // The first tail loss probe retransmits 1 packet.
@@ skipping 200 matching lines @@
 }
 
 TEST_F(QuicSentPacketManagerTest, GetTransmissionTime) {
   EXPECT_EQ(QuicTime::Zero(), manager_.GetRetransmissionTime());
 }
 
 TEST_F(QuicSentPacketManagerTest, GetTransmissionTimeCryptoHandshake) {
   SendCryptoPacket(1);
 
   // Check the min.
-  EXPECT_CALL(*send_algorithm_, SmoothedRtt())
-      .WillRepeatedly(Return(QuicTime::Delta::FromMilliseconds(1)));
+  QuicSentPacketManagerPeer::GetRttStats(&manager_)->set_initial_rtt_us(
+      1 * base::Time::kMicrosecondsPerMillisecond);
   EXPECT_EQ(clock_.Now().Add(QuicTime::Delta::FromMilliseconds(10)),
             manager_.GetRetransmissionTime());
 
   // Test with a standard smoothed RTT.
-  EXPECT_CALL(*send_algorithm_, SmoothedRtt())
-      .WillRepeatedly(Return(QuicTime::Delta::FromMilliseconds(100)));
+  QuicSentPacketManagerPeer::GetRttStats(&manager_)->set_initial_rtt_us(
+      100 * base::Time::kMicrosecondsPerMillisecond);
 
   QuicTime::Delta srtt = manager_.SmoothedRtt();
-  QuicTime expected_time = clock_.Now().Add(QuicTime::Delta::FromMilliseconds(
-      static_cast<int64>(1.5 * srtt.ToMilliseconds())));
+  QuicTime expected_time = clock_.Now().Add(srtt.Multiply(1.5));
   EXPECT_EQ(expected_time, manager_.GetRetransmissionTime());
 
   // Retransmit the packet by invoking the retransmission timeout.
-  clock_.AdvanceTime(QuicTime::Delta::FromMilliseconds(
-      static_cast<int64>(1.5 * srtt.ToMilliseconds())));
+  clock_.AdvanceTime(srtt.Multiply(1.5));
   EXPECT_CALL(*send_algorithm_, OnPacketAbandoned(_, _));
   manager_.OnRetransmissionTimeout();
   RetransmitNextPacket(2);
 
   // The retransmission time should now be twice as far in the future.
-  expected_time = clock_.Now().Add(QuicTime::Delta::FromMilliseconds(
-        static_cast<int64>(2 * 1.5 * srtt.ToMilliseconds())));
+  expected_time = clock_.Now().Add(srtt.Multiply(2).Multiply(1.5));
   EXPECT_EQ(expected_time, manager_.GetRetransmissionTime());
 }
 
 TEST_F(QuicSentPacketManagerTest, GetTransmissionTimeTailLossProbe) {
   QuicSentPacketManagerPeer::SetMaxTailLossProbes(&manager_, 2);
   SendDataPacket(1);
   SendDataPacket(2);
 
   // Check the min.
-  EXPECT_CALL(*send_algorithm_, SmoothedRtt())
-      .WillRepeatedly(Return(QuicTime::Delta::FromMilliseconds(1)));
+  QuicSentPacketManagerPeer::GetRttStats(&manager_)->set_initial_rtt_us(
+      1 * base::Time::kMicrosecondsPerMillisecond);
   EXPECT_EQ(clock_.Now().Add(QuicTime::Delta::FromMilliseconds(10)),
             manager_.GetRetransmissionTime());
 
   // Test with a standard smoothed RTT.
-  EXPECT_CALL(*send_algorithm_, SmoothedRtt())
-      .WillRepeatedly(Return(QuicTime::Delta::FromMilliseconds(100)));
+  QuicSentPacketManagerPeer::GetRttStats(&manager_)->set_initial_rtt_us(
+      100 * base::Time::kMicrosecondsPerMillisecond);
   QuicTime::Delta srtt = manager_.SmoothedRtt();
-  QuicTime::Delta expected_tlp_delay = QuicTime::Delta::FromMilliseconds(
-      static_cast<int64>(2 * srtt.ToMilliseconds()));
+  QuicTime::Delta expected_tlp_delay = srtt.Multiply(2);
   QuicTime expected_time = clock_.Now().Add(expected_tlp_delay);
   EXPECT_EQ(expected_time, manager_.GetRetransmissionTime());
 
   // Retransmit the packet by invoking the retransmission timeout.
   clock_.AdvanceTime(expected_tlp_delay);
   manager_.OnRetransmissionTimeout();
   RetransmitNextPacket(3);
   EXPECT_FALSE(manager_.HasPendingRetransmissions());
 
   expected_time = clock_.Now().Add(expected_tlp_delay);
   EXPECT_EQ(expected_time, manager_.GetRetransmissionTime());
 }
 
 TEST_F(QuicSentPacketManagerTest, GetTransmissionTimeRTO) {
-  EXPECT_CALL(*send_algorithm_, SmoothedRtt())
-      .WillRepeatedly(Return(QuicTime::Delta::FromMilliseconds(100)));
+  QuicSentPacketManagerPeer::GetRttStats(&manager_)->UpdateRtt(
+      QuicTime::Delta::FromMilliseconds(100), QuicTime::Delta::Zero());
 
   SendDataPacket(1);
   SendDataPacket(2);
 
   QuicTime::Delta expected_rto_delay = QuicTime::Delta::FromMilliseconds(500);
   EXPECT_CALL(*send_algorithm_, RetransmissionDelay())
       .WillRepeatedly(Return(expected_rto_delay));
   QuicTime expected_time = clock_.Now().Add(expected_rto_delay);
   EXPECT_EQ(expected_time, manager_.GetRetransmissionTime());
 
@@ skipping 69 matching lines @@
 
   EXPECT_CALL(*loss_algorithm, GetLossTimeout())
       .WillRepeatedly(Return(QuicTime::Zero()));
   SendDataPacket(1);
   SendDataPacket(2);
 
   // Handle an ack which causes the loss algorithm to be evaluated and
   // set the loss timeout.
   EXPECT_CALL(*send_algorithm_, UpdateRtt(_));
   EXPECT_CALL(*send_algorithm_, OnPacketAcked(2, _));
-  EXPECT_CALL(*loss_algorithm, DetectLostPackets(_, _, _, _, _))
+  EXPECT_CALL(*loss_algorithm, DetectLostPackets(_, _, _, _))
       .WillOnce(Return(SequenceNumberSet()));
   ReceivedPacketInfo received_info;
   received_info.largest_observed = 2;
   received_info.missing_packets.insert(1);
   manager_.OnIncomingAck(received_info, clock_.Now());
 
   QuicTime timeout(clock_.Now().Add(QuicTime::Delta::FromMilliseconds(10)));
   EXPECT_CALL(*loss_algorithm, GetLossTimeout())
       .WillRepeatedly(Return(timeout));
   EXPECT_EQ(timeout, manager_.GetRetransmissionTime());
 
   // Fire the retransmission timeout and ensure the loss detection algorithm
   // is invoked.
-  EXPECT_CALL(*loss_algorithm, DetectLostPackets(_, _, _, _, _))
+  EXPECT_CALL(*loss_algorithm, DetectLostPackets(_, _, _, _))
       .WillOnce(Return(SequenceNumberSet()));
   manager_.OnRetransmissionTimeout();
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace net