Upstream version 9.38.198.0
[platform/framework/web/crosswalk.git] / src / net / quic / quic_received_packet_manager.cc
index 2ebbd97..a915e62 100644 (file)
@@ -7,6 +7,7 @@
 #include "base/logging.h"
 #include "base/stl_util.h"
 #include "net/base/linked_hash_map.h"
+#include "net/quic/quic_connection_stats.h"
 
 using std::make_pair;
 using std::max;
@@ -25,17 +26,117 @@ const size_t kMaxPacketsAfterNewMissing = 4;
 
 }
 
+QuicReceivedPacketManager::EntropyTracker::EntropyTracker()
+    :  packets_entropy_hash_(0),
+       first_gap_(1),
+       largest_observed_(0) {
+}
+
+QuicReceivedPacketManager::EntropyTracker::~EntropyTracker() {}
+
+QuicPacketEntropyHash QuicReceivedPacketManager::EntropyTracker::EntropyHash(
+    QuicPacketSequenceNumber sequence_number) const {
+  DCHECK_LE(sequence_number, largest_observed_);
+  if (sequence_number == largest_observed_) {
+    return packets_entropy_hash_;
+  }
+
+  DCHECK_GE(sequence_number, first_gap_);
+  ReceivedEntropyMap::const_iterator it =
+      packets_entropy_.upper_bound(sequence_number);
+  // When this map is empty we should only query entropy for
+  // largest_observed_, since no other entropy can be correctly
+  // calculated, because we're not storing the entropy for any prior packets.
+  // TODO(rtenneti): add support for LOG_IF_EVERY_N_SEC to chromium.
+  // LOG_IF_EVERY_N_SEC(DFATAL, it == packets_entropy_.end(), 10)
+  LOG_IF(DFATAL, it == packets_entropy_.end())
+      << "EntropyHash may be unknown. largest_received: "
+      << largest_observed_
+      << " sequence_number: " << sequence_number;
+
+  // TODO(satyamshekhar): Make this O(1).
+  QuicPacketEntropyHash hash = packets_entropy_hash_;
+  for (; it != packets_entropy_.end(); ++it) {
+    hash ^= it->second;
+  }
+  return hash;
+}
+
+void QuicReceivedPacketManager::EntropyTracker::RecordPacketEntropyHash(
+    QuicPacketSequenceNumber sequence_number,
+    QuicPacketEntropyHash entropy_hash) {
+  if (sequence_number < first_gap_) {
+    DVLOG(1) << "Ignoring received packet entropy for sequence_number:"
+             << sequence_number << " less than largest_peer_sequence_number:"
+             << first_gap_;
+    return;
+  }
+
+  if (sequence_number > largest_observed_) {
+    largest_observed_ = sequence_number;
+  }
+
+  packets_entropy_hash_ ^= entropy_hash;
+  DVLOG(2) << "setting cumulative received entropy hash to: "
+           << static_cast<int>(packets_entropy_hash_)
+           << " updated with sequence number " << sequence_number
+           << " entropy hash: " << static_cast<int>(entropy_hash);
+
+  packets_entropy_.insert(make_pair(sequence_number, entropy_hash));
+  AdvanceFirstGapAndGarbageCollectEntropyMap();
+}
+
+void QuicReceivedPacketManager::EntropyTracker::SetCumulativeEntropyUpTo(
+    QuicPacketSequenceNumber sequence_number,
+    QuicPacketEntropyHash entropy_hash) {
+  DCHECK_LE(sequence_number, largest_observed_);
+  if (sequence_number < first_gap_) {
+    DVLOG(1) << "Ignoring set entropy at:" << sequence_number
+             << " less than first_gap_:" << first_gap_;
+    return;
+  }
+  // Compute the current entropy based on the hash.
+  packets_entropy_hash_ = entropy_hash;
+  ReceivedEntropyMap::iterator it =
+      packets_entropy_.lower_bound(sequence_number);
+  // TODO(satyamshekhar): Make this O(1).
+  for (; it != packets_entropy_.end(); ++it) {
+    packets_entropy_hash_ ^= it->second;
+  }
+  // Update first_gap_ and discard old entropies.
+  first_gap_ = sequence_number;
+  packets_entropy_.erase(
+      packets_entropy_.begin(),
+      packets_entropy_.lower_bound(sequence_number));
+
+  // Garbage collect entries from the beginning of the map.
+  AdvanceFirstGapAndGarbageCollectEntropyMap();
+}
+
+void QuicReceivedPacketManager::EntropyTracker::
+AdvanceFirstGapAndGarbageCollectEntropyMap() {
+  while (!packets_entropy_.empty()) {
+    ReceivedEntropyMap::iterator it = packets_entropy_.begin();
+    if (it->first != first_gap_) {
+      DCHECK_GT(it->first, first_gap_);
+      break;
+    }
+    packets_entropy_.erase(it);
+    ++first_gap_;
+  }
+}
+
 QuicReceivedPacketManager::QuicReceivedPacketManager(
-    CongestionFeedbackType congestion_type)
-    : packets_entropy_hash_(0),
-      largest_sequence_number_(0),
-      peer_largest_observed_packet_(0),
+    CongestionFeedbackType congestion_type,
+    QuicConnectionStats* stats)
+    : peer_largest_observed_packet_(0),
       least_packet_awaited_by_peer_(1),
       peer_least_packet_awaiting_ack_(0),
       time_largest_observed_(QuicTime::Zero()),
-      receive_algorithm_(ReceiveAlgorithmInterface::Create(congestion_type)) {
-  received_info_.largest_observed = 0;
-  received_info_.entropy_hash = 0;
+      receive_algorithm_(ReceiveAlgorithmInterface::Create(congestion_type)),
+      stats_(stats) {
+  ack_frame_.largest_observed = 0;
+  ack_frame_.entropy_hash = 0;
 }
 
 QuicReceivedPacketManager::~QuicReceivedPacketManager() {}
@@ -48,81 +149,76 @@ void QuicReceivedPacketManager::RecordPacketReceived(
   DCHECK(IsAwaitingPacket(sequence_number));
 
   InsertMissingPacketsBetween(
-      &received_info_,
-      max(received_info_.largest_observed + 1, peer_least_packet_awaiting_ack_),
-      header.packet_sequence_number);
+      &ack_frame_,
+      max(ack_frame_.largest_observed + 1, peer_least_packet_awaiting_ack_),
+      sequence_number);
 
-  if (received_info_.largest_observed > header.packet_sequence_number) {
+  if (ack_frame_.largest_observed > sequence_number) {
     // We've gotten one of the out of order packets - remove it from our
     // "missing packets" list.
     DVLOG(1) << "Removing " << sequence_number << " from missing list";
-    received_info_.missing_packets.erase(sequence_number);
+    ack_frame_.missing_packets.erase(sequence_number);
+
+    // Record how out of order stats.
+    ++stats_->packets_reordered;
+    uint32 sequence_gap = ack_frame_.largest_observed - sequence_number;
+    stats_->max_sequence_reordering =
+        max(stats_->max_sequence_reordering, sequence_gap);
+    uint32 reordering_time_us =
+        receipt_time.Subtract(time_largest_observed_).ToMicroseconds();
+    stats_->max_time_reordering_us = max(stats_->max_time_reordering_us,
+                                         reordering_time_us);
   }
-  if (header.packet_sequence_number > received_info_.largest_observed) {
-    received_info_.largest_observed = header.packet_sequence_number;
+  if (sequence_number > ack_frame_.largest_observed) {
+    ack_frame_.largest_observed = sequence_number;
     time_largest_observed_ = receipt_time;
   }
-  RecordPacketEntropyHash(sequence_number, header.entropy_hash);
+  entropy_tracker_.RecordPacketEntropyHash(sequence_number,
+                                           header.entropy_hash);
 
   receive_algorithm_->RecordIncomingPacket(
       bytes, sequence_number, receipt_time);
+
+  ack_frame_.revived_packets.erase(sequence_number);
 }
 
 void QuicReceivedPacketManager::RecordPacketRevived(
     QuicPacketSequenceNumber sequence_number) {
   LOG_IF(DFATAL, !IsAwaitingPacket(sequence_number));
-  received_info_.revived_packets.insert(sequence_number);
+  ack_frame_.revived_packets.insert(sequence_number);
 }
 
 bool QuicReceivedPacketManager::IsMissing(
     QuicPacketSequenceNumber sequence_number) {
-  return ContainsKey(received_info_.missing_packets, sequence_number);
+  return ContainsKey(ack_frame_.missing_packets, sequence_number);
 }
 
 bool QuicReceivedPacketManager::IsAwaitingPacket(
     QuicPacketSequenceNumber sequence_number) {
-  return ::net::IsAwaitingPacket(received_info_, sequence_number);
+  return ::net::IsAwaitingPacket(ack_frame_, sequence_number);
 }
 
 void QuicReceivedPacketManager::UpdateReceivedPacketInfo(
-    ReceivedPacketInfo* received_info,
-    QuicTime approximate_now) {
-  *received_info = received_info_;
-  received_info->entropy_hash = EntropyHash(received_info_.largest_observed);
+    QuicAckFrame* ack_frame, QuicTime approximate_now) {
+  *ack_frame = ack_frame_;
+  ack_frame->entropy_hash = EntropyHash(ack_frame_.largest_observed);
 
   if (time_largest_observed_ == QuicTime::Zero()) {
     // We have received no packets.
-    received_info->delta_time_largest_observed = QuicTime::Delta::Infinite();
+    ack_frame->delta_time_largest_observed = QuicTime::Delta::Infinite();
     return;
   }
 
   if (approximate_now < time_largest_observed_) {
     // Approximate now may well be "in the past".
-    received_info->delta_time_largest_observed = QuicTime::Delta::Zero();
+    ack_frame->delta_time_largest_observed = QuicTime::Delta::Zero();
     return;
   }
 
-  received_info->delta_time_largest_observed =
+  ack_frame->delta_time_largest_observed =
       approximate_now.Subtract(time_largest_observed_);
 }
 
-void QuicReceivedPacketManager::RecordPacketEntropyHash(
-    QuicPacketSequenceNumber sequence_number,
-    QuicPacketEntropyHash entropy_hash) {
-  if (sequence_number < largest_sequence_number_) {
-    DVLOG(1) << "Ignoring received packet entropy for sequence_number:"
-               << sequence_number << " less than largest_peer_sequence_number:"
-               << largest_sequence_number_;
-    return;
-  }
-  packets_entropy_.insert(make_pair(sequence_number, entropy_hash));
-  packets_entropy_hash_ ^= entropy_hash;
-  DVLOG(2) << "setting cumulative received entropy hash to: "
-           << static_cast<int>(packets_entropy_hash_)
-           << " updated with sequence number " << sequence_number
-           << " entropy hash: " << static_cast<int>(entropy_hash);
-}
-
 bool QuicReceivedPacketManager::GenerateCongestionFeedback(
     QuicCongestionFeedbackFrame* feedback) {
   return receive_algorithm_->GenerateCongestionFeedback(feedback);
@@ -130,110 +226,62 @@ bool QuicReceivedPacketManager::GenerateCongestionFeedback(
 
 QuicPacketEntropyHash QuicReceivedPacketManager::EntropyHash(
     QuicPacketSequenceNumber sequence_number) const {
-  DCHECK_LE(sequence_number, received_info_.largest_observed);
-  DCHECK_GE(sequence_number, largest_sequence_number_);
-  if (sequence_number == received_info_.largest_observed) {
-    return packets_entropy_hash_;
-  }
-
-  ReceivedEntropyMap::const_iterator it =
-      packets_entropy_.upper_bound(sequence_number);
-  // When this map is empty we should only query entropy for
-  // received_info_.largest_observed, since no other entropy can be correctly
-  // calculated, because we're not storing the entropy for any prior packets.
-  // TODO(rtenneti): add support for LOG_IF_EVERY_N_SEC to chromium.
-  // LOG_IF_EVERY_N_SEC(DFATAL, it == packets_entropy_.end(), 10)
-  LOG_IF(DFATAL, it == packets_entropy_.end())
-      << "EntropyHash may be unknown. largest_received: "
-      << received_info_.largest_observed
-      << " sequence_number: " << sequence_number;
-
-  // TODO(satyamshekhar): Make this O(1).
-  QuicPacketEntropyHash hash = packets_entropy_hash_;
-  for (; it != packets_entropy_.end(); ++it) {
-    hash ^= it->second;
-  }
-  return hash;
-}
-
-void QuicReceivedPacketManager::RecalculateEntropyHash(
-    QuicPacketSequenceNumber peer_least_unacked,
-    QuicPacketEntropyHash entropy_hash) {
-  DCHECK_LE(peer_least_unacked, received_info_.largest_observed);
-  if (peer_least_unacked < largest_sequence_number_) {
-    DVLOG(1) << "Ignoring received peer_least_unacked:" << peer_least_unacked
-               << " less than largest_peer_sequence_number:"
-               << largest_sequence_number_;
-    return;
-  }
-  largest_sequence_number_ = peer_least_unacked;
-  packets_entropy_hash_ = entropy_hash;
-  ReceivedEntropyMap::iterator it =
-      packets_entropy_.lower_bound(peer_least_unacked);
-  // TODO(satyamshekhar): Make this O(1).
-  for (; it != packets_entropy_.end(); ++it) {
-    packets_entropy_hash_ ^= it->second;
-  }
-  // Discard entropies before least unacked.
-  packets_entropy_.erase(
-      packets_entropy_.begin(),
-      packets_entropy_.lower_bound(
-          min(peer_least_unacked, received_info_.largest_observed)));
+  return entropy_tracker_.EntropyHash(sequence_number);
 }
 
 void QuicReceivedPacketManager::UpdatePacketInformationReceivedByPeer(
-    const ReceivedPacketInfo& received_info) {
+    const QuicAckFrame& ack_frame) {
   // ValidateAck should fail if largest_observed ever shrinks.
-  DCHECK_LE(peer_largest_observed_packet_, received_info.largest_observed);
-  peer_largest_observed_packet_ = received_info.largest_observed;
+  DCHECK_LE(peer_largest_observed_packet_, ack_frame.largest_observed);
+  peer_largest_observed_packet_ = ack_frame.largest_observed;
 
-  if (received_info.missing_packets.empty()) {
+  if (ack_frame.missing_packets.empty()) {
     least_packet_awaited_by_peer_ = peer_largest_observed_packet_ + 1;
   } else {
-    least_packet_awaited_by_peer_ = *(received_info.missing_packets.begin());
+    least_packet_awaited_by_peer_ = *(ack_frame.missing_packets.begin());
   }
 }
 
 bool QuicReceivedPacketManager::DontWaitForPacketsBefore(
     QuicPacketSequenceNumber least_unacked) {
-  received_info_.revived_packets.erase(
-      received_info_.revived_packets.begin(),
-      received_info_.revived_packets.lower_bound(least_unacked));
-  size_t missing_packets_count = received_info_.missing_packets.size();
-  received_info_.missing_packets.erase(
-      received_info_.missing_packets.begin(),
-      received_info_.missing_packets.lower_bound(least_unacked));
-  return missing_packets_count != received_info_.missing_packets.size();
+  ack_frame_.revived_packets.erase(
+      ack_frame_.revived_packets.begin(),
+      ack_frame_.revived_packets.lower_bound(least_unacked));
+  size_t missing_packets_count = ack_frame_.missing_packets.size();
+  ack_frame_.missing_packets.erase(
+      ack_frame_.missing_packets.begin(),
+      ack_frame_.missing_packets.lower_bound(least_unacked));
+  return missing_packets_count != ack_frame_.missing_packets.size();
 }
 
 void QuicReceivedPacketManager::UpdatePacketInformationSentByPeer(
-    const SentPacketInfo& sent_info) {
+    const QuicStopWaitingFrame& stop_waiting) {
   // ValidateAck() should fail if peer_least_packet_awaiting_ack_ shrinks.
-  DCHECK_LE(peer_least_packet_awaiting_ack_, sent_info.least_unacked);
-  if (sent_info.least_unacked > peer_least_packet_awaiting_ack_) {
-    bool missed_packets = DontWaitForPacketsBefore(sent_info.least_unacked);
-    if (missed_packets || sent_info.least_unacked >
-            received_info_.largest_observed + 1) {
+  DCHECK_LE(peer_least_packet_awaiting_ack_, stop_waiting.least_unacked);
+  if (stop_waiting.least_unacked > peer_least_packet_awaiting_ack_) {
+    bool missed_packets = DontWaitForPacketsBefore(stop_waiting.least_unacked);
+    if (missed_packets) {
       DVLOG(1) << "Updating entropy hashed since we missed packets";
       // There were some missing packets that we won't ever get now. Recalculate
       // the received entropy hash.
-      RecalculateEntropyHash(sent_info.least_unacked, sent_info.entropy_hash);
+      entropy_tracker_.SetCumulativeEntropyUpTo(stop_waiting.least_unacked,
+                                                stop_waiting.entropy_hash);
     }
-    peer_least_packet_awaiting_ack_ = sent_info.least_unacked;
+    peer_least_packet_awaiting_ack_ = stop_waiting.least_unacked;
   }
-  DCHECK(received_info_.missing_packets.empty() ||
-         *received_info_.missing_packets.begin() >=
+  DCHECK(ack_frame_.missing_packets.empty() ||
+         *ack_frame_.missing_packets.begin() >=
              peer_least_packet_awaiting_ack_);
 }
 
 bool QuicReceivedPacketManager::HasMissingPackets() {
-  return !received_info_.missing_packets.empty();
+  return !ack_frame_.missing_packets.empty();
 }
 
 bool QuicReceivedPacketManager::HasNewMissingPackets() {
   return HasMissingPackets() &&
-      (received_info_.largest_observed -
-       *received_info_.missing_packets.rbegin()) <= kMaxPacketsAfterNewMissing;
+      (ack_frame_.largest_observed -
+       *ack_frame_.missing_packets.rbegin()) <= kMaxPacketsAfterNewMissing;
 }
 
 }  // namespace net