From 92a00ca91affab8564b8875387758914ddc9785b Mon Sep 17 00:00:00 2001 From: Ian Gudger Date: Wed, 18 Mar 2020 16:25:20 -0700 Subject: Store segment transmit count. This will aid in segment reordering detection. Updates #691 PiperOrigin-RevId: 301692638 --- pkg/tcpip/transport/tcp/segment.go | 6 +++--- pkg/tcpip/transport/tcp/snd.go | 3 ++- 2 files changed, 5 insertions(+), 4 deletions(-) (limited to 'pkg/tcpip/transport') diff --git a/pkg/tcpip/transport/tcp/segment.go b/pkg/tcpip/transport/tcp/segment.go index 1c10da5ca..5d0bc4f72 100644 --- a/pkg/tcpip/transport/tcp/segment.go +++ b/pkg/tcpip/transport/tcp/segment.go @@ -56,9 +56,9 @@ type segment struct { options []byte `state:".([]byte)"` hasNewSACKInfo bool rcvdTime time.Time `state:".(unixTime)"` - // xmitTime is the last transmit time of this segment. A zero value - // indicates that the segment has yet to be transmitted. - xmitTime time.Time `state:".(unixTime)"` + // xmitTime is the last transmit time of this segment. + xmitTime time.Time `state:".(unixTime)"` + xmitCount uint32 } func newSegment(r *stack.Route, id stack.TransportEndpointID, pkt tcpip.PacketBuffer) *segment { diff --git a/pkg/tcpip/transport/tcp/snd.go b/pkg/tcpip/transport/tcp/snd.go index b74b61e7d..657c3146e 100644 --- a/pkg/tcpip/transport/tcp/snd.go +++ b/pkg/tcpip/transport/tcp/snd.go @@ -1229,7 +1229,7 @@ func (s *sender) handleRcvdSegment(seg *segment) { // sendSegment sends the specified segment. func (s *sender) sendSegment(seg *segment) *tcpip.Error { - if !seg.xmitTime.IsZero() { + if seg.xmitCount > 0 { s.ep.stack.Stats().TCP.Retransmits.Increment() s.ep.stats.SendErrors.Retransmits.Increment() if s.sndCwnd < s.sndSsthresh { @@ -1237,6 +1237,7 @@ func (s *sender) sendSegment(seg *segment) *tcpip.Error { } } seg.xmitTime = time.Now() + seg.xmitCount++ return s.sendSegmentFromView(seg.data, seg.flags, seg.sequenceNumber) } -- cgit v1.2.3