X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fvnet%2Fsession%2Fsession_node.c;h=fde1931aaf979cccb67185b1c8d5a2ae4ab4867a;hb=82fc5fd447ec2b140f1d6a8641106361176f1b80;hp=35704b75a0aeec3d3e8c4fc8839fefae3d1d5393;hpb=b0ffbee67bd17f6880a02184d18cd94156f2389e;p=vpp.git

diff --git a/src/vnet/session/session_node.c b/src/vnet/session/session_node.c
index 35704b75a0a..fde1931aaf9 100644
--- a/src/vnet/session/session_node.c
+++ b/src/vnet/session/session_node.c
@@ -25,12 +25,204 @@
 #include <vnet/session/session_debug.h>
 #include <svm/queue.h>
 
-static void session_mq_accepted_reply_handler (void *data);
+#define app_check_thread_and_barrier(_fn, _arg)				\
+  if (!vlib_thread_is_main_w_barrier ())				\
+    {									\
+     vlib_rpc_call_main_thread (_fn, (u8 *) _arg, sizeof(*_arg));	\
+      return;								\
+   }
 
 static void
-accepted_notify_cb (void *data, u32 data_len)
+session_mq_listen_handler (void *data)
 {
-  session_mq_accepted_reply_handler (data);
+  session_listen_msg_t *mp = (session_listen_msg_t *) data;
+  vnet_listen_args_t _a, *a = &_a;
+  app_worker_t *app_wrk;
+  application_t *app;
+  int rv;
+
+  app_check_thread_and_barrier (session_mq_listen_handler, mp);
+
+  app = application_lookup (mp->client_index);
+  if (!app)
+    return;
+
+  clib_memset (a, 0, sizeof (*a));
+  a->sep.is_ip4 = mp->is_ip4;
+  clib_memcpy_fast (&a->sep.ip, &mp->ip, sizeof (mp->ip));
+  a->sep.port = mp->port;
+  a->sep.fib_index = mp->vrf;
+  a->sep.sw_if_index = ENDPOINT_INVALID_INDEX;
+  a->sep.transport_proto = mp->proto;
+  a->sep_ext.ckpair_index = mp->ckpair_index;
+  a->app_index = app->app_index;
+  a->wrk_map_index = mp->wrk_index;
+
+  if ((rv = vnet_listen (a)))
+    clib_warning ("listen returned: %d", rv);
+
+  app_wrk = application_get_worker (app, mp->wrk_index);
+  mq_send_session_bound_cb (app_wrk->wrk_index, mp->context, a->handle, rv);
+  return;
+}
+
+static void
+session_mq_listen_uri_handler (void *data)
+{
+  session_listen_uri_msg_t *mp = (session_listen_uri_msg_t *) data;
+  vnet_listen_args_t _a, *a = &_a;
+  app_worker_t *app_wrk;
+  application_t *app;
+  int rv;
+
+  app_check_thread_and_barrier (session_mq_listen_uri_handler, mp);
+
+  app = application_lookup (mp->client_index);
+  if (!app)
+    return;
+
+  clib_memset (a, 0, sizeof (*a));
+  a->uri = (char *) mp->uri;
+  a->app_index = app->app_index;
+  rv = vnet_bind_uri (a);
+
+  app_wrk = application_get_worker (app, 0);
+  mq_send_session_bound_cb (app_wrk->wrk_index, mp->context, a->handle, rv);
+}
+
+static void
+session_mq_connect_handler (void *data)
+{
+  session_connect_msg_t *mp = (session_connect_msg_t *) data;
+  vnet_connect_args_t _a, *a = &_a;
+  app_worker_t *app_wrk;
+  application_t *app;
+  int rv;
+
+  app_check_thread_and_barrier (session_mq_connect_handler, mp);
+
+  app = application_lookup (mp->client_index);
+  if (!app)
+    return;
+
+  clib_memset (a, 0, sizeof (*a));
+  a->sep.is_ip4 = mp->is_ip4;
+  clib_memcpy_fast (&a->sep.ip, &mp->ip, sizeof (mp->ip));
+  a->sep.port = mp->port;
+  a->sep.transport_proto = mp->proto;
+  a->sep.peer.fib_index = mp->vrf;
+  a->sep.peer.sw_if_index = ENDPOINT_INVALID_INDEX;
+  a->sep_ext.parent_handle = mp->parent_handle;
+  a->sep_ext.ckpair_index = mp->ckpair_index;
+  if (mp->hostname_len)
+    {
+      vec_validate (a->sep_ext.hostname, mp->hostname_len - 1);
+      clib_memcpy_fast (a->sep_ext.hostname, mp->hostname, mp->hostname_len);
+    }
+  a->api_context = mp->context;
+  a->app_index = app->app_index;
+  a->wrk_map_index = mp->wrk_index;
+
+  if ((rv = vnet_connect (a)))
+    {
+      clib_warning ("connect returned: %U", format_vnet_api_errno, rv);
+      app_wrk = application_get_worker (app, mp->wrk_index);
+      mq_send_session_connected_cb (app_wrk->wrk_index, mp->context, 0,
+				    /* is_fail */ 1);
+    }
+
+  vec_free (a->sep_ext.hostname);
+}
+
+static void
+session_mq_connect_uri_handler (void *data)
+{
+  session_connect_uri_msg_t *mp = (session_connect_uri_msg_t *) data;
+  vnet_connect_args_t _a, *a = &_a;
+  app_worker_t *app_wrk;
+  application_t *app;
+  int rv;
+
+  app_check_thread_and_barrier (session_mq_connect_uri_handler, mp);
+
+  app = application_lookup (mp->client_index);
+  if (!app)
+    return;
+
+  clib_memset (a, 0, sizeof (*a));
+  a->uri = (char *) mp->uri;
+  a->api_context = mp->context;
+  a->app_index = app->app_index;
+  if ((rv = vnet_connect_uri (a)))
+    {
+      clib_warning ("connect_uri returned: %d", rv);
+      app_wrk = application_get_worker (app, 0 /* default wrk only */ );
+      mq_send_session_connected_cb (app_wrk->wrk_index, mp->context, 0,
+				    /* is_fail */ 1);
+    }
+}
+
+static void
+session_mq_disconnect_handler (void *data)
+{
+  session_disconnect_msg_t *mp = (session_disconnect_msg_t *) data;
+  vnet_disconnect_args_t _a, *a = &_a;
+  application_t *app;
+
+  app = application_lookup (mp->client_index);
+  if (!app)
+    return;
+
+  a->app_index = app->app_index;
+  a->handle = mp->handle;
+  vnet_disconnect_session (a);
+}
+
+static void
+app_mq_detach_handler (void *data)
+{
+  session_app_detach_msg_t *mp = (session_app_detach_msg_t *) data;
+  vnet_app_detach_args_t _a, *a = &_a;
+  application_t *app;
+
+  app_check_thread_and_barrier (app_mq_detach_handler, mp);
+
+  app = application_lookup (mp->client_index);
+  if (!app)
+    return;
+
+  a->app_index = app->app_index;
+  a->api_client_index = mp->client_index;
+  vnet_application_detach (a);
+}
+
+static void
+session_mq_unlisten_handler (void *data)
+{
+  session_unlisten_msg_t *mp = (session_unlisten_msg_t *) data;
+  vnet_unlisten_args_t _a, *a = &_a;
+  app_worker_t *app_wrk;
+  application_t *app;
+  int rv;
+
+  app_check_thread_and_barrier (session_mq_unlisten_handler, mp);
+
+  app = application_lookup (mp->client_index);
+  if (!app)
+    return;
+
+  clib_memset (a, 0, sizeof (*a));
+  a->app_index = app->app_index;
+  a->handle = mp->handle;
+  a->wrk_map_index = mp->wrk_index;
+  if ((rv = vnet_unlisten (a)))
+    clib_warning ("unlisten returned: %d", rv);
+
+  app_wrk = application_get_worker (app, a->wrk_map_index);
+  if (!app_wrk)
+    return;
+
+  mq_send_unlisten_reply (app_wrk, mp->handle, mp->context, rv);
 }
 
 static void
@@ -56,8 +248,8 @@ session_mq_accepted_reply_handler (void *data)
   if (vlib_num_workers () && vlib_get_thread_index () != 0
       && session_thread_from_handle (mp->handle) == 0)
     {
-      vl_api_rpc_call_main_thread (accepted_notify_cb, data,
-				   sizeof (session_accepted_reply_msg_t));
+      vlib_rpc_call_main_thread (session_mq_accepted_reply_handler,
+				 (u8 *) mp, sizeof (*mp));
       return;
     }
 
@@ -121,7 +313,7 @@ session_mq_reset_reply_handler (void *data)
   app_wrk = app_worker_get (s->app_wrk_index);
   if (!app_wrk || app_wrk->app_index != app->app_index)
     {
-      clib_warning ("App % does not own handle 0x%lx!", app->app_index,
+      clib_warning ("App %u does not own handle 0x%lx!", app->app_index,
 		    mp->handle);
       return;
     }
@@ -175,7 +367,6 @@ session_mq_disconnected_handler (void *data)
   svm_msg_q_lock_and_alloc_msg_w_ring (app_wrk->event_queue,
 				       SESSION_MQ_CTRL_EVT_RING,
 				       SVM_Q_WAIT, msg);
-  svm_msg_q_unlock (app_wrk->event_queue);
   evt = svm_msg_q_msg_data (app_wrk->event_queue, msg);
   clib_memset (evt, 0, sizeof (*evt));
   evt->event_type = SESSION_CTRL_EVT_DISCONNECTED_REPLY;
@@ -183,7 +374,7 @@ session_mq_disconnected_handler (void *data)
   rmp->handle = mp->handle;
   rmp->context = mp->context;
   rmp->retval = rv;
-  svm_msg_q_add (app_wrk->event_queue, msg, SVM_Q_WAIT);
+  svm_msg_q_add_and_unlock (app_wrk->event_queue, msg);
 }
 
 static void
@@ -250,13 +441,12 @@ session_mq_worker_update_handler (void *data)
       svm_msg_q_lock_and_alloc_msg_w_ring (app_wrk->event_queue,
 					   SESSION_MQ_CTRL_EVT_RING,
 					   SVM_Q_WAIT, msg);
-      svm_msg_q_unlock (app_wrk->event_queue);
       evt = svm_msg_q_msg_data (app_wrk->event_queue, msg);
       clib_memset (evt, 0, sizeof (*evt));
       evt->event_type = SESSION_CTRL_EVT_REQ_WORKER_UPDATE;
       wump = (session_req_worker_update_msg_t *) evt->data;
       wump->session_handle = mp->handle;
-      svm_msg_q_add (app_wrk->event_queue, msg, SVM_Q_WAIT);
+      svm_msg_q_add_and_unlock (app_wrk->event_queue, msg);
       return;
     }
 
@@ -268,7 +458,6 @@ session_mq_worker_update_handler (void *data)
   svm_msg_q_lock_and_alloc_msg_w_ring (app_wrk->event_queue,
 				       SESSION_MQ_CTRL_EVT_RING,
 				       SVM_Q_WAIT, msg);
-  svm_msg_q_unlock (app_wrk->event_queue);
   evt = svm_msg_q_msg_data (app_wrk->event_queue, msg);
   clib_memset (evt, 0, sizeof (*evt));
   evt->event_type = SESSION_CTRL_EVT_WORKER_UPDATE_REPLY;
@@ -277,7 +466,7 @@ session_mq_worker_update_handler (void *data)
   rmp->rx_fifo = pointer_to_uword (s->rx_fifo);
   rmp->tx_fifo = pointer_to_uword (s->tx_fifo);
   rmp->segment_handle = session_segment_handle (s);
-  svm_msg_q_add (app_wrk->event_queue, msg, SVM_Q_WAIT);
+  svm_msg_q_add_and_unlock (app_wrk->event_queue, msg);
 
   /*
    * Retransmit messages that may have been lost
@@ -515,12 +704,21 @@ session_tx_not_ready (session_t * s, u8 peek_data)
 {
   if (peek_data)
     {
+      if (PREDICT_TRUE (s->session_state == SESSION_STATE_READY))
+	return 0;
       /* Can retransmit for closed sessions but can't send new data if
        * session is not ready or closed */
-      if (s->session_state < SESSION_STATE_READY)
+      else if (s->session_state < SESSION_STATE_READY)
 	return 1;
-      if (s->session_state >= SESSION_STATE_TRANSPORT_CLOSED)
-	return 2;
+      else if (s->session_state >= SESSION_STATE_TRANSPORT_CLOSED)
+	{
+	  /* Allow closed transports to still send custom packets.
+	   * For instance, tcp may want to send acks in time-wait. */
+	  if (s->session_state != SESSION_STATE_TRANSPORT_DELETED
+	      && (s->flags & SESSION_F_CUSTOM_TX))
+	    return 0;
+	  return 2;
+	}
     }
   return 0;
 }
@@ -642,7 +840,6 @@ session_tx_fifo_read_and_snd_i (session_worker_t * wrk,
   tp = session_get_transport_proto (ctx->s);
   ctx->transport_vft = transport_protocol_get_vft (tp);
   ctx->tc = session_tx_get_transport (ctx, peek_data);
-  ctx->snd_mss = ctx->transport_vft->send_mss (ctx->tc);
 
   if (PREDICT_FALSE (e->event_type == SESSION_IO_EVT_TX_FLUSH))
     {
@@ -656,6 +853,9 @@ session_tx_fifo_read_and_snd_i (session_worker_t * wrk,
       ctx->s->flags &= ~SESSION_F_CUSTOM_TX;
       n_custom_tx = ctx->transport_vft->custom_tx (ctx->tc, max_burst);
       *n_tx_packets += n_custom_tx;
+      if (PREDICT_FALSE
+	  (ctx->s->session_state >= SESSION_STATE_TRANSPORT_CLOSED))
+	return SESSION_TX_OK;
       max_burst -= n_custom_tx;
       if (!max_burst)
 	{
@@ -664,6 +864,7 @@ session_tx_fifo_read_and_snd_i (session_worker_t * wrk,
 	}
     }
 
+  ctx->snd_mss = ctx->transport_vft->send_mss (ctx->tc);
   ctx->snd_space = transport_connection_snd_space (ctx->tc,
 						   vm->clib_time.
 						   last_cpu_time,
@@ -783,7 +984,7 @@ session_tx_fifo_read_and_snd_i (session_worker_t * wrk,
     vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
 
   *n_tx_packets += ctx->n_segs_per_evt;
-  transport_connection_update_tx_stats (ctx->tc, ctx->max_len_to_snd);
+  transport_connection_update_tx_bytes (ctx->tc, ctx->max_len_to_snd);
   vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 
   SESSION_EVT (SESSION_EVT_DEQ, ctx->s, ctx->max_len_to_snd, ctx->max_dequeue,
@@ -850,14 +1051,94 @@ session_event_get_session (session_event_t * e, u8 thread_index)
 }
 
 always_inline void
-session_event_dispatch (session_worker_t * wrk, vlib_node_runtime_t * node,
-			session_evt_elt_t * elt, u32 thread_index,
-			int *n_tx_packets)
+session_event_dispatch_ctrl (session_worker_t * wrk, session_evt_elt_t * elt)
+{
+  clib_llist_index_t ei;
+  void (*fp) (void *);
+  session_event_t *e;
+  session_t *s;
+
+  ei = clib_llist_entry_index (wrk->event_elts, elt);
+  e = &elt->evt;
+
+  switch (e->event_type)
+    {
+    case SESSION_CTRL_EVT_RPC:
+      fp = e->rpc_args.fp;
+      (*fp) (e->rpc_args.arg);
+      break;
+    case SESSION_CTRL_EVT_CLOSE:
+      s = session_get_from_handle_if_valid (e->session_handle);
+      if (PREDICT_FALSE (!s))
+	break;
+      session_transport_close (s);
+      break;
+    case SESSION_CTRL_EVT_RESET:
+      s = session_get_from_handle_if_valid (e->session_handle);
+      if (PREDICT_FALSE (!s))
+	break;
+      session_transport_reset (s);
+      break;
+    case SESSION_CTRL_EVT_LISTEN:
+      session_mq_listen_handler (session_evt_ctrl_data (wrk, elt));
+      break;
+    case SESSION_CTRL_EVT_LISTEN_URI:
+      session_mq_listen_uri_handler (session_evt_ctrl_data (wrk, elt));
+      break;
+    case SESSION_CTRL_EVT_UNLISTEN:
+      session_mq_unlisten_handler (session_evt_ctrl_data (wrk, elt));
+      break;
+    case SESSION_CTRL_EVT_CONNECT:
+      session_mq_connect_handler (session_evt_ctrl_data (wrk, elt));
+      break;
+    case SESSION_CTRL_EVT_CONNECT_URI:
+      session_mq_connect_uri_handler (session_evt_ctrl_data (wrk, elt));
+      break;
+    case SESSION_CTRL_EVT_DISCONNECT:
+      session_mq_disconnect_handler (session_evt_ctrl_data (wrk, elt));
+      break;
+    case SESSION_CTRL_EVT_DISCONNECTED:
+      session_mq_disconnected_handler (session_evt_ctrl_data (wrk, elt));
+      break;
+    case SESSION_CTRL_EVT_ACCEPTED_REPLY:
+      session_mq_accepted_reply_handler (session_evt_ctrl_data (wrk, elt));
+      break;
+    case SESSION_CTRL_EVT_DISCONNECTED_REPLY:
+      session_mq_disconnected_reply_handler (session_evt_ctrl_data (wrk,
+								    elt));
+      break;
+    case SESSION_CTRL_EVT_RESET_REPLY:
+      session_mq_reset_reply_handler (session_evt_ctrl_data (wrk, elt));
+      break;
+    case SESSION_CTRL_EVT_WORKER_UPDATE:
+      session_mq_worker_update_handler (session_evt_ctrl_data (wrk, elt));
+      break;
+    case SESSION_CTRL_EVT_APP_DETACH:
+      app_mq_detach_handler (session_evt_ctrl_data (wrk, elt));
+      break;
+    default:
+      clib_warning ("unhandled event type %d", e->event_type);
+    }
+
+  /* Regrab elements in case pool moved */
+  elt = pool_elt_at_index (wrk->event_elts, ei);
+  if (!clib_llist_elt_is_linked (elt, evt_list))
+    {
+      e = &elt->evt;
+      if (e->event_type >= SESSION_CTRL_EVT_BOUND)
+	session_evt_ctrl_data_free (wrk, elt);
+      session_evt_elt_free (wrk, elt);
+    }
+}
+
+always_inline void
+session_event_dispatch_io (session_worker_t * wrk, vlib_node_runtime_t * node,
+			   session_evt_elt_t * elt, u32 thread_index,
+			   int *n_tx_packets)
 {
   session_main_t *smm = &session_main;
   app_worker_t *app_wrk;
   clib_llist_index_t ei;
-  void (*fp) (void *);
   session_event_t *e;
   session_t *s;
 
@@ -887,12 +1168,6 @@ session_event_dispatch (session_worker_t * wrk, vlib_node_runtime_t * node,
       transport_app_rx_evt (session_get_transport_proto (s),
 			    s->connection_index, s->thread_index);
       break;
-    case SESSION_CTRL_EVT_CLOSE:
-      s = session_get_from_handle_if_valid (e->session_handle);
-      if (PREDICT_FALSE (!s))
-	break;
-      session_transport_close (s);
-      break;
     case SESSION_IO_EVT_BUILTIN_RX:
       s = session_event_get_session (e, thread_index);
       if (PREDICT_FALSE (!s || s->session_state >= SESSION_STATE_CLOSING))
@@ -907,27 +1182,6 @@ session_event_dispatch (session_worker_t * wrk, vlib_node_runtime_t * node,
       if (PREDICT_TRUE (s != 0))
 	session_tx_fifo_dequeue_internal (wrk, node, elt, n_tx_packets);
       break;
-    case SESSION_CTRL_EVT_RPC:
-      fp = e->rpc_args.fp;
-      (*fp) (e->rpc_args.arg);
-      break;
-    case SESSION_CTRL_EVT_DISCONNECTED:
-      session_mq_disconnected_handler (e->data);
-      break;
-    case SESSION_CTRL_EVT_ACCEPTED_REPLY:
-      session_mq_accepted_reply_handler (e->data);
-      break;
-    case SESSION_CTRL_EVT_CONNECTED_REPLY:
-      break;
-    case SESSION_CTRL_EVT_DISCONNECTED_REPLY:
-      session_mq_disconnected_reply_handler (e->data);
-      break;
-    case SESSION_CTRL_EVT_RESET_REPLY:
-      session_mq_reset_reply_handler (e->data);
-      break;
-    case SESSION_CTRL_EVT_WORKER_UPDATE:
-      session_mq_worker_update_handler (e->data);
-      break;
     default:
       clib_warning ("unhandled event type %d", e->event_type);
     }
@@ -938,6 +1192,43 @@ session_event_dispatch (session_worker_t * wrk, vlib_node_runtime_t * node,
     session_evt_elt_free (wrk, elt);
 }
 
+/* *INDENT-OFF* */
+static const u32 session_evt_msg_sizes[] = {
+#define _(symc, sym) 							\
+  [SESSION_CTRL_EVT_ ## symc] = sizeof (session_ ## sym ##_msg_t),
+  foreach_session_ctrl_evt
+#undef _
+};
+/* *INDENT-ON* */
+
+always_inline void
+session_evt_add_to_list (session_worker_t * wrk, session_event_t * evt)
+{
+  session_evt_elt_t *elt;
+
+  if (evt->event_type >= SESSION_CTRL_EVT_RPC)
+    {
+      elt = session_evt_alloc_ctrl (wrk);
+      if (evt->event_type >= SESSION_CTRL_EVT_BOUND)
+	{
+	  elt->evt.ctrl_data_index = session_evt_ctrl_data_alloc (wrk);
+	  elt->evt.event_type = evt->event_type;
+	  clib_memcpy_fast (session_evt_ctrl_data (wrk, elt), evt->data,
+			    session_evt_msg_sizes[evt->event_type]);
+	}
+      else
+	{
+	  /* Internal control events fit into io events footprint */
+	  clib_memcpy_fast (&elt->evt, evt, sizeof (elt->evt));
+	}
+    }
+  else
+    {
+      elt = session_evt_alloc_new (wrk);
+      clib_memcpy_fast (&elt->evt, evt, sizeof (elt->evt));
+    }
+}
+
 static uword
 session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
 		       vlib_frame_t * frame)
@@ -975,14 +1266,7 @@ session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
 	{
 	  svm_msg_q_sub_w_lock (mq, msg);
 	  evt = svm_msg_q_msg_data (mq, msg);
-	  if (evt->event_type > SESSION_IO_EVT_BUILTIN_TX)
-	    elt = session_evt_alloc_ctrl (wrk);
-	  else
-	    elt = session_evt_alloc_new (wrk);
-	  /* Works because reply messages are smaller than a session evt.
-	   * If we ever need to support bigger messages this needs to be
-	   * fixed */
-	  clib_memcpy_fast (&elt->evt, evt, sizeof (elt->evt));
+	  session_evt_add_to_list (wrk, evt);
 	  svm_msg_q_free_msg (mq, msg);
 	}
       svm_msg_q_unlock (mq);
@@ -997,7 +1281,7 @@ session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
   /* *INDENT-OFF* */
   clib_llist_foreach_safe (wrk->event_elts, evt_list, ctrl_he, elt, ({
     clib_llist_remove (wrk->event_elts, evt_list, elt);
-    session_event_dispatch (wrk, node, elt, thread_index, &n_tx_packets);
+    session_event_dispatch_ctrl (wrk, elt);
   }));
   /* *INDENT-ON* */
 
@@ -1022,7 +1306,7 @@ session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
 	continue;
       }
 
-    session_event_dispatch (wrk, node, elt, thread_index, &n_tx_packets);
+    session_event_dispatch_io (wrk, node, elt, thread_index, &n_tx_packets);
   }));
   /* *INDENT-ON* */
 
@@ -1039,7 +1323,7 @@ session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
 
       clib_llist_pop_first (wrk->event_elts, evt_list, elt, old_he);
       ei = clib_llist_entry_index (wrk->event_elts, elt);
-      session_event_dispatch (wrk, node, elt, thread_index, &n_tx_packets);
+      session_event_dispatch_io (wrk, node, elt, thread_index, &n_tx_packets);
 
       old_he = pool_elt_at_index (wrk->event_elts, wrk->old_head);
       if (n_tx_packets >= VLIB_FRAME_SIZE || ei == old_ti)
@@ -1058,6 +1342,7 @@ session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
 VLIB_REGISTER_NODE (session_queue_node) =
 {
   .function = session_queue_node_fn,
+  .flags = VLIB_NODE_FLAG_TRACE_SUPPORTED,
   .name = "session-queue",
   .format_trace = format_session_queue_trace,
   .type = VLIB_NODE_TYPE_INPUT,