Improvements to tcp rx path and debugging

- Increment rcv_nxt for fin packets
- Call tcp_segment_rcv only if buffer has data
- Parse rcv opts before deleting half-open connection
- Fix initial rcv_wnd
- Improved event logging

Change-Id: I9b83c04f432c4cec832c480b03e534deff02c3b1
Signed-off-by: Florin Coras <fcoras@cisco.com>

5 files changed, 130 insertions, 14 deletions

diff --git a/src/vnet/session/node.c b/src/vnet/session/node.c
index 983b78b8..8d703b0b 100644
--- a/src/vnet/session/node.c
+++ b/src/vnet/session/node.c
@@ -443,6 +443,79 @@ dump_thread_0_event_queue (void)
     }
 }
 
+static u8
+session_node_cmp_event (session_fifo_event_t * e, svm_fifo_t * f)
+{
+  stream_session_t *s;
+  switch (e->event_type)
+    {
+    case FIFO_EVENT_APP_RX:
+    case FIFO_EVENT_APP_TX:
+    case FIFO_EVENT_BUILTIN_RX:
+      if (e->fifo == f)
+	return 1;
+      break;
+    case FIFO_EVENT_DISCONNECT:
+      break;
+    case FIFO_EVENT_RPC:
+      s = stream_session_get_from_handle (e->session_handle);
+      if (!s)
+	{
+	  clib_warning ("session has event but doesn't exist!");
+	  break;
+	}
+      if (s->server_rx_fifo == f || s->server_tx_fifo == f)
+	return 1;
+      break;
+    default:
+      break;
+    }
+  return 0;
+}
+
+u8
+session_node_lookup_fifo_event (svm_fifo_t * f, session_fifo_event_t * e)
+{
+  session_manager_main_t *smm = vnet_get_session_manager_main ();
+  unix_shared_memory_queue_t *q;
+  session_fifo_event_t *pending_event_vector, *evt;
+  int i, index, found = 0;
+  i8 *headp;
+  u8 thread_index;
+
+  ASSERT (e);
+  thread_index = f->master_thread_index;
+  /*
+   * Search evt queue
+   */
+  q = smm->vpp_event_queues[thread_index];
+  index = q->head;
+  for (i = 0; i < q->cursize; i++)
+    {
+      headp = (i8 *) (&q->data[0] + q->elsize * index);
+      clib_memcpy (e, headp, q->elsize);
+      found = session_node_cmp_event (e, f);
+      if (found)
+	break;
+      if (++index == q->maxsize)
+	index = 0;
+    }
+  /*
+   * Search pending events vector
+   */
+  pending_event_vector = smm->pending_event_vector[thread_index];
+  vec_foreach (evt, pending_event_vector)
+  {
+    found = session_node_cmp_event (evt, f);
+    if (found)
+      {
+	clib_memcpy (e, evt, sizeof (*evt));
+	break;
+      }
+  }
+  return found;
+}
+
 static uword
 session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
 		       vlib_frame_t * frame)
diff --git a/src/vnet/session/session.c b/src/vnet/session/session.c
index 2c2a27c1..09bc00e7 100644
--- a/src/vnet/session/session.c
+++ b/src/vnet/session/session.c
@@ -32,6 +32,22 @@ static transport_proto_vft_t *tp_vfts;
 
 session_manager_main_t session_manager_main;
 
+transport_connection_t *
+stream_session_lookup_half_open (transport_connection_t * tc)
+{
+  session_manager_main_t *smm = &session_manager_main;
+  session_kv4_t kv4;
+  int rv;
+  if (tc->is_ip4)
+    {
+      make_v4_ss_kv_from_tc (&kv4, tc);
+      rv = clib_bihash_search_inline_16_8 (&smm->v4_half_open_hash, &kv4);
+      if (rv == 0)
+	return tp_vfts[tc->proto].get_half_open (kv4.value & 0xFFFFFFFFULL);
+    }
+  return 0;
+}
+
 /*
  * Session lookup key; (src-ip, dst-ip, src-port, dst-port, session-type)
  * Value: (owner thread index << 32 | session_index);
@@ -501,7 +517,7 @@ stream_session_create_i (segment_manager_t * sm, transport_connection_t * tc,
   tc->s_index = s->session_index;
 
   /* Add to the main lookup table */
-  value = (((u64) thread_index) << 32) | (u64) s->session_index;
+  value = stream_session_handle (s);
   stream_session_table_add_for_tc (tc, value);
 
   *ret_s = s;
@@ -817,8 +833,18 @@ stream_session_connect_notify (transport_connection_t * tc, u8 sst,
     }
 
   /* Notify client */
-  app->cb_fns.session_connected_callback (app->index, api_context, new_s,
-					  is_fail);
+  if (app->cb_fns.session_connected_callback (app->index, api_context, new_s,
+					      is_fail))
+    {
+      clib_warning ("failed to notify app");
+      if (!is_fail)
+	stream_session_disconnect (new_s);
+    }
+  else
+    {
+      if (!is_fail)
+	new_s->session_state = SESSION_STATE_READY;
+    }
 
   /* Cleanup session lookup */
   stream_session_half_open_table_del (smm, sst, tc);
@@ -862,15 +888,19 @@ void
 stream_session_delete (stream_session_t * s)
 {
   session_manager_main_t *smm = vnet_get_session_manager_main ();
+  int rv;
 
   /* Delete from the main lookup table. */
-  stream_session_table_del (smm, s);
+  if ((rv = stream_session_table_del (smm, s)))
+    clib_warning ("hash delete error, rv %d", rv);
 
   /* Cleanup fifo segments */
   segment_manager_dealloc_fifos (s->svm_segment_index, s->server_rx_fifo,
 				 s->server_tx_fifo);
 
   pool_put (smm->sessions[s->thread_index], s);
+  if (CLIB_DEBUG)
+    memset (s, 0xFA, sizeof (*s));
 }
 
 /**
diff --git a/src/vnet/session/session.h b/src/vnet/session/session.h
index 6069c574..6c616326 100644
--- a/src/vnet/session/session.h
+++ b/src/vnet/session/session.h
@@ -170,6 +170,8 @@ typedef int
 extern session_fifo_rx_fn session_tx_fifo_peek_and_snd;
 extern session_fifo_rx_fn session_tx_fifo_dequeue_and_snd;
 
+u8 session_node_lookup_fifo_event (svm_fifo_t * f, session_fifo_event_t * e);
+
 struct _session_manager_main
 {
   /** Lookup tables for established sessions and listeners */
@@ -289,6 +291,8 @@ transport_connection_t *stream_session_lookup_transport6 (ip6_address_t * lcl,
 
 stream_session_t *stream_session_lookup_listener (ip46_address_t * lcl,
 						  u16 lcl_port, u8 proto);
+transport_connection_t
+  * stream_session_lookup_half_open (transport_connection_t * tc);
 void stream_session_table_add_for_tc (transport_connection_t * tc, u64 value);
 int stream_session_table_del_for_tc (transport_connection_t * tc);
 
diff --git a/src/vnet/session/session_api.c b/src/vnet/session/session_api.c
index 60f764af..6bee3e27 100755
--- a/src/vnet/session/session_api.c
+++ b/src/vnet/session/session_api.c
@@ -184,13 +184,6 @@ send_session_connected_callback (u32 app_index, u32 api_context,
     }
 
   vl_msg_api_send_shmem (q, (u8 *) & mp);
-
-  /* Remove client if connect failed */
-  if (!is_fail)
-    {
-      s->session_state = SESSION_STATE_READY;
-    }
-
   return 0;
 }
 
diff --git a/src/vnet/session/session_cli.c b/src/vnet/session/session_cli.c
index e8e6f99c..4d432977 100755
--- a/src/vnet/session/session_cli.c
+++ b/src/vnet/session/session_cli.c
@@ -19,8 +19,24 @@ u8 *
 format_stream_session_fifos (u8 * s, va_list * args)
 {
   stream_session_t *ss = va_arg (*args, stream_session_t *);
+  int verbose = va_arg (*args, int);
+  session_fifo_event_t _e, *e = &_e;
+  u8 found;
+
   s = format (s, " Rx fifo: %U", format_svm_fifo, ss->server_rx_fifo, 1);
+  if (verbose > 2 && ss->server_rx_fifo->has_event)
+    {
+      found = session_node_lookup_fifo_event (ss->server_rx_fifo, e);
+      s = format (s, " session node event: %s\n",
+		  found ? "found" : "not found");
+    }
   s = format (s, " Tx fifo: %U", format_svm_fifo, ss->server_tx_fifo, 1);
+  if (verbose > 2 && ss->server_tx_fifo->has_event)
+    {
+      found = session_node_lookup_fifo_event (ss->server_tx_fifo, e);
+      s = format (s, " session node event: %s\n",
+		  found ? "found" : "not found");
+    }
   return s;
 }
 
@@ -55,7 +71,7 @@ format_stream_session (u8 * s, va_list * args)
       if (verbose == 1)
 	s = format (s, "%v", str);
       if (verbose > 1)
-	s = format (s, "%U", format_stream_session_fifos, ss);
+	s = format (s, "%U", format_stream_session_fifos, ss, verbose);
     }
   else if (ss->session_state == SESSION_STATE_LISTENING)
     {
@@ -75,7 +91,7 @@ format_stream_session (u8 * s, va_list * args)
       if (verbose == 1)
 	s = format (s, "%v", str);
       if (verbose > 1)
-	s = format (s, "%U", format_stream_session_fifos, ss);
+	s = format (s, "%U", format_stream_session_fifos, ss, verbose);
     }
   else
     {
@@ -248,7 +264,7 @@ show_session_command_fn (vlib_main_t * vm, unformat_input_t * input,
 
   if (one_session)
     {
-      vlib_cli_output (vm, "%U", format_stream_session, s, 2);
+      vlib_cli_output (vm, "%U", format_stream_session, s, 3);
       return 0;
     }