1 files changed, 127 insertions, 118 deletions

diff --git a/chromium/net/quic/quic_sent_packet_manager.h b/chromium/net/quic/quic_sent_packet_manager.h
index 71c61e93c03..2e75786119a 100644
--- a/chromium/net/quic/quic_sent_packet_manager.h
+++ b/chromium/net/quic/quic_sent_packet_manager.h
@@ -14,14 +14,14 @@
 #include <vector>
 
 #include "base/containers/hash_tables.h"
+#include "base/memory/scoped_ptr.h"
 #include "net/base/linked_hash_map.h"
+#include "net/quic/congestion_control/loss_detection_interface.h"
+#include "net/quic/congestion_control/rtt_stats.h"
 #include "net/quic/congestion_control/send_algorithm_interface.h"
 #include "net/quic/quic_ack_notifier_manager.h"
 #include "net/quic/quic_protocol.h"
-
-NET_EXPORT_PRIVATE extern bool FLAGS_track_retransmission_history;
-NET_EXPORT_PRIVATE extern bool FLAGS_limit_rto_increase_for_tests;
-NET_EXPORT_PRIVATE extern bool FLAGS_enable_quic_pacing;
+#include "net/quic/quic_unacked_packet_map.h"
 
 namespace net {
 
@@ -32,6 +32,7 @@ class QuicSentPacketManagerPeer;
 
 class QuicClock;
 class QuicConfig;
+struct QuicConnectionStats;
 
 // Class which tracks the set of packets sent on a QUIC connection and contains
 // a send algorithm to decide when to send new packets.  It keeps track of any
@@ -40,6 +41,19 @@ class QuicConfig;
 // previous transmission is acked, the data will not be retransmitted.
 class NET_EXPORT_PRIVATE QuicSentPacketManager {
  public:
+  // Interface which gets callbacks from the QuicSentPacketManager at
+  // interesting points.  Implementations must not mutate the state of
+  // the packet manager or connection as a result of these callbacks.
+  class NET_EXPORT_PRIVATE DebugDelegate {
+   public:
+    virtual ~DebugDelegate() {}
+
+    // Called when a spurious retransmission is detected.
+    virtual void OnSpuriousPacketRetransmition(
+        TransmissionType transmission_type,
+        QuicByteCount byte_size) {}
+  };
+
   // Struct to store the pending retransmission information.
   struct PendingRetransmission {
     PendingRetransmission(QuicPacketSequenceNumber sequence_number,
@@ -58,25 +72,15 @@ class NET_EXPORT_PRIVATE QuicSentPacketManager {
         QuicSequenceNumberLength sequence_number_length;
   };
 
-  // Interface which provides callbacks that the manager needs.
-  class NET_EXPORT_PRIVATE HelperInterface {
-   public:
-    virtual ~HelperInterface();
-
-    // Called to return the sequence number of the next packet to be sent.
-    virtual QuicPacketSequenceNumber GetNextPacketSequenceNumber() = 0;
-  };
-
   QuicSentPacketManager(bool is_server,
-                        HelperInterface* helper,
                         const QuicClock* clock,
-                        CongestionFeedbackType congestion_type);
+                        QuicConnectionStats* stats,
+                        CongestionFeedbackType congestion_type,
+                        LossDetectionType loss_type);
   virtual ~QuicSentPacketManager();
 
   virtual void SetFromConfig(const QuicConfig& config);
 
-  virtual void SetMaxPacketSize(QuicByteCount max_packet_size);
-
   // Called when a new packet is serialized.  If the packet contains
   // retransmittable data, it will be added to the unacked packet map.
   void OnSerializedPacket(const SerializedPacket& serialized_packet);
@@ -87,22 +91,24 @@ class NET_EXPORT_PRIVATE QuicSentPacketManager {
   void OnRetransmittedPacket(QuicPacketSequenceNumber old_sequence_number,
                              QuicPacketSequenceNumber new_sequence_number);
 
-  // Processes the incoming ack and returns true if the retransmission or ack
-  // alarm should be reset.
-  bool OnIncomingAck(const ReceivedPacketInfo& received_info,
+  // Processes the incoming ack.
+  void OnIncomingAck(const ReceivedPacketInfo& received_info,
                      QuicTime ack_receive_time);
 
-  // Discards any information for the packet corresponding to |sequence_number|.
-  // If this packet has been retransmitted, information on those packets
-  // will be discarded as well.
-  void DiscardUnackedPacket(QuicPacketSequenceNumber sequence_number);
-
   // Returns true if the non-FEC packet |sequence_number| is unacked.
   bool IsUnacked(QuicPacketSequenceNumber sequence_number) const;
 
   // Requests retransmission of all unacked packets of |retransmission_type|.
   void RetransmitUnackedPackets(RetransmissionType retransmission_type);
 
+  // Retransmits the oldest pending packet there is still a tail loss probe
+  // pending.  Invoked after OnRetransmissionTimeout.
+  bool MaybeRetransmitTailLossProbe();
+
+  // Removes the retransmittable frames from all unencrypted packets to ensure
+  // they don't get retransmitted.
+  void NeuterUnencryptedPackets();
+
   // Returns true if the unacked packet |sequence_number| has retransmittable
   // frames.  This will only return false if the packet has been acked, if a
   // previous transmission of this packet was ACK'd, or if this packet has been
@@ -117,39 +123,19 @@ class NET_EXPORT_PRIVATE QuicSentPacketManager {
 
   bool HasUnackedPackets() const;
 
-  // Returns the number of unacked packets which have retransmittable frames.
-  size_t GetNumRetransmittablePackets() const;
-
-  // Returns the smallest sequence number of a sent packet which has not been
-  // acked by the peer.  Excludes any packets which have been retransmitted
-  // with a new sequence number. If all packets have been acked, returns the
-  // sequence number of the next packet that will be sent.
+  // Returns the smallest sequence number of a serialized packet which has not
+  // been acked by the peer.  If there are no unacked packets, returns 0.
   QuicPacketSequenceNumber GetLeastUnackedSentPacket() const;
 
-  // Returns the set of sequence numbers of all unacked packets.
-  // Test only.
-  SequenceNumberSet GetUnackedPackets() const;
-
-  // Returns true if |sequence_number| is a previous transmission of packet.
-  bool IsPreviousTransmission(QuicPacketSequenceNumber sequence_number) const;
-
-  // TODO(ianswett): Combine the congestion control related methods below with
-  // some of the methods above and cleanup the resulting code.
-  // Called when we have received an ack frame from peer.
-  // Returns a set containing all the sequence numbers to be nack retransmitted
-  // as a result of the ack.
-  virtual SequenceNumberSet OnIncomingAckFrame(
-      const ReceivedPacketInfo& received_info,
-      const QuicTime& ack_receive_time);
-
   // Called when a congestion feedback frame is received from peer.
   virtual void OnIncomingQuicCongestionFeedbackFrame(
       const QuicCongestionFeedbackFrame& frame,
       const QuicTime& feedback_receive_time);
 
   // Called when we have sent bytes to the peer.  This informs the manager both
-  // the number of bytes sent and if they were retransmitted.
-  virtual void OnPacketSent(QuicPacketSequenceNumber sequence_number,
+  // the number of bytes sent and if they were retransmitted.  Returns true if
+  // the sender should reset the retransmission timer.
+  virtual bool OnPacketSent(QuicPacketSequenceNumber sequence_number,
                             QuicTime sent_time,
                             QuicByteCount bytes,
                             TransmissionType transmission_type,
@@ -158,28 +144,23 @@ class NET_EXPORT_PRIVATE QuicSentPacketManager {
   // Called when the retransmission timer expires.
   virtual void OnRetransmissionTimeout();
 
-  // Called when a packet is timed out, such as an RTO.  Removes the bytes from
-  // the congestion manager, but does not change the congestion window size.
-  virtual void OnPacketAbandoned(QuicPacketSequenceNumber sequence_number);
-
   // Calculate the time until we can send the next packet to the wire.
   // Note 1: When kUnknownWaitTime is returned, there is no need to poll
   // TimeUntilSend again until we receive an OnIncomingAckFrame event.
   // Note 2: Send algorithms may or may not use |retransmit| in their
   // calculations.
   virtual QuicTime::Delta TimeUntilSend(QuicTime now,
-                                        TransmissionType transmission_type,
-                                        HasRetransmittableData retransmittable,
-                                        IsHandshake handshake);
+                                        HasRetransmittableData retransmittable);
 
   // Returns amount of time for delayed ack timer.
-  const QuicTime::Delta DelayedAckTime();
+  const QuicTime::Delta DelayedAckTime() const;
 
-  // Returns the current RTO delay.
-  const QuicTime::Delta GetRetransmissionDelay() const;
+  // Returns the current delay for the retransmission timer, which may send
+  // either a tail loss probe or do a full RTO.  Returns QuicTime::Zero() if
+  // there are no retransmittable packets.
+  const QuicTime GetRetransmissionTime() const;
 
-  // Returns the estimated smoothed RTT calculated by the congestion algorithm.
-  const QuicTime::Delta SmoothedRtt() const;
+  const RttStats* GetRttStats() const;
 
   // Returns the estimated bandwidth calculated by the congestion algorithm.
   QuicBandwidth BandwidthEstimate() const;
@@ -195,73 +176,91 @@ class NET_EXPORT_PRIVATE QuicSentPacketManager {
 
   bool using_pacing() const { return using_pacing_; }
 
+  void set_debug_delegate(DebugDelegate* debug_delegate) {
+    debug_delegate_ = debug_delegate;
+  }
 
  private:
   friend class test::QuicConnectionPeer;
   friend class test::QuicSentPacketManagerPeer;
 
-  struct TransmissionInfo {
-    TransmissionInfo()
-        : retransmittable_frames(NULL),
-          sequence_number_length(PACKET_1BYTE_SEQUENCE_NUMBER),
-          sent_time(QuicTime::Zero()),
-          previous_transmissions(NULL) { }
-    TransmissionInfo(RetransmittableFrames* retransmittable_frames,
-                     QuicSequenceNumberLength sequence_number_length)
-        : retransmittable_frames(retransmittable_frames),
-          sequence_number_length(sequence_number_length),
-          sent_time(QuicTime::Zero()),
-          previous_transmissions(NULL) {
-    }
-
-    RetransmittableFrames* retransmittable_frames;
-    QuicSequenceNumberLength sequence_number_length;
-    // Zero when the packet is serialized, non-zero once it's sent.
-    QuicTime sent_time;
-    // Stores all previous transmissions if the packet has been retransmitted,
-    // and is NULL otherwise.
-    SequenceNumberSet* previous_transmissions;
+  // The retransmission timer is a single timer which switches modes depending
+  // upon connection state.
+  enum RetransmissionTimeoutMode {
+    // A conventional TCP style RTO.
+    RTO_MODE,
+    // A tail loss probe.  By default, QUIC sends up to two before RTOing.
+    TLP_MODE,
+    // Retransmission of handshake packets prior to handshake completion.
+    HANDSHAKE_MODE,
+    // Re-invoke the loss detection when a packet is not acked before the
+    // loss detection algorithm expects.
+    LOSS_MODE,
   };
 
   typedef linked_hash_map<QuicPacketSequenceNumber,
-                          TransmissionInfo> UnackedPacketMap;
-  typedef linked_hash_map<QuicPacketSequenceNumber,
                           TransmissionType> PendingRetransmissionMap;
-  typedef base::hash_map<QuicPacketSequenceNumber, SequenceNumberSet*>
-                         PreviousTransmissionMap;
 
   // Process the incoming ack looking for newly ack'd data packets.
   void HandleAckForSentPackets(const ReceivedPacketInfo& received_info);
 
+  // Returns the current retransmission mode.
+  RetransmissionTimeoutMode GetRetransmissionMode() const;
+
+  // Retransmits all crypto stream packets.
+  void RetransmitCryptoPackets();
+
+  // Retransmits all the packets and abandons by invoking a full RTO.
+  void RetransmitAllPackets();
+
+  // Returns the timer for retransmitting crypto handshake packets.
+  const QuicTime::Delta GetCryptoRetransmissionDelay() const;
+
+  // Returns the timer for a new tail loss probe.
+  const QuicTime::Delta GetTailLossProbeDelay() const;
+
+  // Returns the retransmission timeout, after which a full RTO occurs.
+  const QuicTime::Delta GetRetransmissionDelay() const;
+
   // Update the RTT if the ack is for the largest acked sequence number.
-  void MaybeUpdateRTT(const ReceivedPacketInfo& received_info,
+  // Returns true if the rtt was updated.
+  bool MaybeUpdateRTT(const ReceivedPacketInfo& received_info,
                       const QuicTime& ack_receive_time);
 
-  // Marks |sequence_number| as having been seen by the peer.  Returns an
-  // iterator to the next remaining unacked packet.
-  UnackedPacketMap::iterator MarkPacketReceivedByPeer(
-      QuicPacketSequenceNumber sequence_number);
-
-  // Simply removes the entries, if any, from the unacked packet map
-  // and the retransmission map.
-  void DiscardPacket(QuicPacketSequenceNumber sequence_number);
+  // Invokes the loss detection algorithm and loses and retransmits packets if
+  // necessary.
+  void InvokeLossDetection(QuicTime time);
+
+  // Invokes OnCongestionEvent if |rtt_updated| is true, there are pending acks,
+  // or pending losses.  Clears pending acks and pending losses afterwards.
+  // |bytes_in_flight| is the number of bytes in flight before the losses or
+  // acks.
+  void MaybeInvokeCongestionEvent(bool rtt_updated,
+                                  QuicByteCount bytes_in_flight);
+
+  // Marks |sequence_number| as having been revived by the peer, but not
+  // received, so the packet remains pending if it is and the congestion control
+  // does not consider the packet acked.
+  void MarkPacketRevived(QuicPacketSequenceNumber sequence_number,
+                         QuicTime::Delta delta_largest_observed);
+
+  // Removes the retransmittability and pending properties from the packet at
+  // |it| due to receipt by the peer.  Returns an iterator to the next remaining
+  // unacked packet.
+  QuicUnackedPacketMap::const_iterator MarkPacketHandled(
+      QuicUnackedPacketMap::const_iterator it,
+      QuicTime::Delta delta_largest_observed);
 
   // Request that |sequence_number| be retransmitted after the other pending
-  // retransmissions.  Returns false if there are no retransmittable frames for
-  // |sequence_number| and true if it will be retransmitted.
-  bool MarkForRetransmission(QuicPacketSequenceNumber sequence_number,
+  // retransmissions.  Does not add it to the retransmissions if it's already
+  // a pending retransmission.
+  void MarkForRetransmission(QuicPacketSequenceNumber sequence_number,
                              TransmissionType transmission_type);
 
-  // Returns the length of the serialized sequence number for
-  // the packet |sequence_number|.
-  QuicSequenceNumberLength GetSequenceNumberLength(
-      QuicPacketSequenceNumber sequence_number) const;
-
-  // Clears up to |num_to_clear| previous transmissions in order to make room
-  // in the ack frame for new acks.
-  void ClearPreviousRetransmissions(size_t num_to_clear);
-
-  void CleanupPacketHistory();
+  // Notify observers about spurious retransmits.
+  void RecordSpuriousRetransmissions(
+      const SequenceNumberSet& all_transmissions,
+      QuicPacketSequenceNumber acked_sequence_number);
 
   // Newly serialized retransmittable and fec packets are added to this map,
   // which contains owning pointers to any contained frames.  If a packet is
@@ -271,7 +270,7 @@ class NET_EXPORT_PRIVATE QuicSentPacketManager {
   // If the old packet is acked before the new packet, then the old entry will
   // be removed from the map and the new entry's retransmittable frames will be
   // set to NULL.
-  UnackedPacketMap unacked_packets_;
+  QuicUnackedPacketMap unacked_packets_;
 
   // Pending retransmissions which have not been packetized and sent yet.
   PendingRetransmissionMap pending_retransmissions_;
@@ -279,25 +278,35 @@ class NET_EXPORT_PRIVATE QuicSentPacketManager {
   // Tracks if the connection was created by the server.
   bool is_server_;
 
-  HelperInterface* helper_;
-
   // An AckNotifier can register to be informed when ACKs have been received for
   // all packets that a given block of data was sent in. The AckNotifierManager
   // maintains the currently active notifiers.
   AckNotifierManager ack_notifier_manager_;
 
   const QuicClock* clock_;
+  QuicConnectionStats* stats_;
+  DebugDelegate* debug_delegate_;
+  RttStats rtt_stats_;
   scoped_ptr<SendAlgorithmInterface> send_algorithm_;
-  // Tracks the send time, size, and nack count of sent packets.  Packets are
-  // removed after 5 seconds and they've been removed from pending_packets_.
-  SendAlgorithmInterface::SentPacketsMap packet_history_map_;
-  // Packets that are outstanding and have not been abandoned or lost.
-  SequenceNumberSet pending_packets_;
-  QuicTime::Delta rtt_sample_;  // RTT estimate from the most recent ACK.
+  scoped_ptr<LossDetectionInterface> loss_algorithm_;
+
+  QuicPacketSequenceNumber largest_observed_;  // From the most recent ACK.
   // Number of times the RTO timer has fired in a row without receiving an ack.
   size_t consecutive_rto_count_;
+  // Number of times the tail loss probe has been sent.
+  size_t consecutive_tlp_count_;
+  // Number of times the crypto handshake has been retransmitted.
+  size_t consecutive_crypto_retransmission_count_;
+  // Whether a tlp packet can be sent even if the send algorithm says not to.
+  bool pending_tlp_transmission_;
+  // Maximum number of tail loss probes to send before firing an RTO.
+  size_t max_tail_loss_probes_;
   bool using_pacing_;
 
+  // Sets of packets acked and lost as a result of the last congestion event.
+  SendAlgorithmInterface::CongestionMap packets_acked_;
+  SendAlgorithmInterface::CongestionMap packets_lost_;
+
   DISALLOW_COPY_AND_ASSIGN(QuicSentPacketManager);
 };