diff options
| -rw-r--r-- | pkg/sentry/socket/netstack/netstack.go | 1 | ||||
| -rw-r--r-- | pkg/tcpip/tcpip.go | 4 | ||||
| -rw-r--r-- | pkg/tcpip/transport/tcp/snd.go | 7 | ||||
| -rw-r--r-- | pkg/tcpip/transport/tcp/tcp_rack_test.go | 44 |
4 files changed, 56 insertions, 0 deletions
diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go index 0f8cbe7e2..9b844b0c0 100644 --- a/pkg/sentry/socket/netstack/netstack.go +++ b/pkg/sentry/socket/netstack/netstack.go @@ -274,6 +274,7 @@ var Metrics = tcpip.Stats{ Timeouts: mustCreateMetric("/netstack/tcp/timeouts", "Number of times RTO expired."), ChecksumErrors: mustCreateMetric("/netstack/tcp/checksum_errors", "Number of segments dropped due to bad checksums."), FailedPortReservations: mustCreateMetric("/netstack/tcp/failed_port_reservations", "Number of time TCP failed to reserve a port."), + SegmentsAckedWithDSACK: mustCreateMetric("/netstack/tcp/segments_acked_with_dsack", "Number of segments for which DSACK was received."), }, UDP: tcpip.UDPStats{ PacketsReceived: mustCreateMetric("/netstack/udp/packets_received", "Number of UDP datagrams received via HandlePacket."), diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go index 8f2658f64..55683b4fb 100644 --- a/pkg/tcpip/tcpip.go +++ b/pkg/tcpip/tcpip.go @@ -1845,6 +1845,10 @@ type TCPStats struct { // FailedPortReservations is the number of times TCP failed to reserve // a port. FailedPortReservations *StatCounter + + // SegmentsAckedWithDSACK is the number of segments acknowledged with + // DSACK. + SegmentsAckedWithDSACK *StatCounter } // UDPStats collects UDP-specific stats. diff --git a/pkg/tcpip/transport/tcp/snd.go b/pkg/tcpip/transport/tcp/snd.go index 72d58dcff..92a66f17e 100644 --- a/pkg/tcpip/transport/tcp/snd.go +++ b/pkg/tcpip/transport/tcp/snd.go @@ -1154,6 +1154,13 @@ func (s *sender) walkSACK(rcvdSeg *segment) { idx := 0 n := len(rcvdSeg.parsedOptions.SACKBlocks) if checkDSACK(rcvdSeg) { + dsackBlock := rcvdSeg.parsedOptions.SACKBlocks[0] + numDSACK := uint64(dsackBlock.End-dsackBlock.Start) / uint64(s.MaxPayloadSize) + // numDSACK can be zero when DSACK is sent for subsegments. + if numDSACK < 1 { + numDSACK = 1 + } + s.ep.stack.Stats().TCP.SegmentsAckedWithDSACK.IncrementBy(numDSACK) s.rc.setDSACKSeen(true) idx = 1 n-- diff --git a/pkg/tcpip/transport/tcp/tcp_rack_test.go b/pkg/tcpip/transport/tcp/tcp_rack_test.go index d826ff724..89e9fb886 100644 --- a/pkg/tcpip/transport/tcp/tcp_rack_test.go +++ b/pkg/tcpip/transport/tcp/tcp_rack_test.go @@ -540,6 +540,28 @@ func TestRACKDetectDSACK(t *testing.T) { case invalidDSACKDetected: t.Fatalf("RACK DSACK detected when there is no duplicate SACK") } + + metricPollFn := func() error { + tcpStats := c.Stack().Stats().TCP + stats := []struct { + stat *tcpip.StatCounter + name string + want uint64 + }{ + // Check DSACK was received for one segment. + {tcpStats.SegmentsAckedWithDSACK, "stats.TCP.SegmentsAckedWithDSACK", 1}, + } + for _, s := range stats { + if got, want := s.stat.Value(), s.want; got != want { + return fmt.Errorf("got %s.Value() = %d, want = %d", s.name, got, want) + } + } + return nil + } + + if err := testutil.Poll(metricPollFn, 1*time.Second); err != nil { + t.Error(err) + } } // TestRACKDetectDSACKWithOutOfOrder tests that RACK detects DSACK with out of @@ -680,6 +702,28 @@ func TestRACKDetectDSACKSingleDup(t *testing.T) { case invalidDSACKDetected: t.Fatalf("RACK DSACK detected when there is no duplicate SACK") } + + metricPollFn := func() error { + tcpStats := c.Stack().Stats().TCP + stats := []struct { + stat *tcpip.StatCounter + name string + want uint64 + }{ + // Check DSACK was received for a subsegment. + {tcpStats.SegmentsAckedWithDSACK, "stats.TCP.SegmentsAckedWithDSACK", 1}, + } + for _, s := range stats { + if got, want := s.stat.Value(), s.want; got != want { + return fmt.Errorf("got %s.Value() = %d, want = %d", s.name, got, want) + } + } + return nil + } + + if err := testutil.Poll(metricPollFn, 1*time.Second); err != nil { + t.Error(err) + } } // TestRACKDetectDSACKDupWithCumulativeACK tests DSACK for two non-contiguous |