TCP ooo reception fixes

- Improve svm fifo handling of out-of-order segments
- Ensure tsval_recent is updated only if rcv_las falls withing the
  segments's sequence space
- Avoid directly dropping old ACKs
- Improve debugging

Change-Id: I88dbe2394a0ad7eb389a4cc12d013a13733953aa
Signed-off-by: Florin Coras <fcoras@cisco.com>

2 files changed, 19 insertions, 3 deletions

diff --git a/src/vnet/session/session.c b/src/vnet/session/session.c
index d17c93f8f69..e92bb440601 100644
--- a/src/vnet/session/session.c
+++ b/src/vnet/session/session.c
@@ -609,6 +609,21 @@ session_manager_flush_enqueue_events (u32 thread_index)
   return errors;
 }
 
+/**
+ * Init fifo tail and head pointers
+ *
+ * Useful if transport uses absolute offsets for tracking ooo segments.
+ */
+void
+stream_session_init_fifos_pointers (transport_connection_t * tc,
+				    u32 rx_pointer, u32 tx_pointer)
+{
+  stream_session_t *s;
+  s = stream_session_get (tc->s_index, tc->thread_index);
+  svm_fifo_init_pointers (s->server_rx_fifo, rx_pointer);
+  svm_fifo_init_pointers (s->server_tx_fifo, tx_pointer);
+}
+
 void
 stream_session_connect_notify (transport_connection_t * tc, u8 sst,
 			       u8 is_fail)
diff --git a/src/vnet/session/session.h b/src/vnet/session/session.h
index 8cd72f3577a..f41a8a96eb5 100644
--- a/src/vnet/session/session.h
+++ b/src/vnet/session/session.h
@@ -352,9 +352,10 @@ stream_session_peek_bytes (transport_connection_t * tc, u8 * buffer,
 			   u32 offset, u32 max_bytes);
 u32 stream_session_dequeue_drop (transport_connection_t * tc, u32 max_bytes);
 
-void
-stream_session_connect_notify (transport_connection_t * tc, u8 sst,
-			       u8 is_fail);
+void stream_session_connect_notify (transport_connection_t * tc, u8 sst,
+				    u8 is_fail);
+void stream_session_init_fifos_pointers (transport_connection_t * tc,
+					 u32 rx_pointer, u32 tx_pointer);
 
 void stream_session_accept_notify (transport_connection_t * tc);
 void stream_session_disconnect_notify (transport_connection_t * tc);