X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fvnet%2Fsession%2Fapplication_worker.c;h=7e03171b1159937aa4253278f3c7abc456030ff6;hb=94a6df005d9e94f3b836ad3c93d1464b4a840499;hp=2717ef01870807e1e48c72d46fcb52c3b7549242;hpb=f6c4313b6aa7746fe97afd398ce68c2efbef0600;p=vpp.git

diff --git a/src/vnet/session/application_worker.c b/src/vnet/session/application_worker.c
index 2717ef01870..7e03171b115 100644
--- a/src/vnet/session/application_worker.c
+++ b/src/vnet/session/application_worker.c
@@ -32,8 +32,8 @@ app_worker_alloc (application_t * app)
   app_wrk->app_index = app->app_index;
   app_wrk->wrk_map_index = ~0;
   app_wrk->connects_seg_manager = APP_INVALID_SEGMENT_MANAGER_INDEX;
-  app_wrk->first_segment_manager = APP_INVALID_SEGMENT_MANAGER_INDEX;
-  APP_DBG ("New app %v worker %u", app_get_name (app), app_wrk->wrk_index);
+  clib_spinlock_init (&app_wrk->detached_seg_managers_lock);
+  APP_DBG ("New app %v worker %u", app->name, app_wrk->wrk_index);
   return app_wrk;
 }
 
@@ -56,12 +56,11 @@ app_worker_free (app_worker_t * app_wrk)
 {
   application_t *app = application_get (app_wrk->app_index);
   vnet_unlisten_args_t _a, *a = &_a;
-  u64 handle, *handles = 0;
+  u64 handle, *handles = 0, *sm_indices = 0;
   segment_manager_t *sm;
-  u32 sm_index;
-  int i;
-  app_listener_t *al;
   session_t *ls;
+  u32 sm_index;
+  int i, j;
 
   /*
    *  Listener cleanup
@@ -70,21 +69,30 @@ app_worker_free (app_worker_t * app_wrk)
   /* *INDENT-OFF* */
   hash_foreach (handle, sm_index, app_wrk->listeners_table, ({
     ls = listen_session_get_from_handle (handle);
-    al = app_listener_get (app, ls->al_index);
-    vec_add1 (handles, app_listener_handle (al));
+    vec_add1 (handles, app_listen_session_handle (ls));
+    vec_add1 (sm_indices, sm_index);
     sm = segment_manager_get (sm_index);
-    sm->app_wrk_index = SEGMENT_MANAGER_INVALID_APP_INDEX;
   }));
   /* *INDENT-ON* */
 
   for (i = 0; i < vec_len (handles); i++)
     {
+      /* Cleanup listener */
       a->app_index = app->app_index;
       a->wrk_map_index = app_wrk->wrk_map_index;
       a->handle = handles[i];
-      /* seg manager is removed when unbind completes */
       (void) vnet_unlisten (a);
+
+      sm = segment_manager_get_if_valid (sm_indices[i]);
+      if (sm && !segment_manager_app_detached (sm))
+	{
+	  sm->first_is_protected = 0;
+	  segment_manager_init_free (sm);
+	}
     }
+  vec_reset_length (handles);
+  vec_free (sm_indices);
+  hash_free (app_wrk->listeners_table);
 
   /*
    * Connects segment manager cleanup
@@ -95,25 +103,48 @@ app_worker_free (app_worker_t * app_wrk)
       sm = segment_manager_get (app_wrk->connects_seg_manager);
       sm->app_wrk_index = SEGMENT_MANAGER_INVALID_APP_INDEX;
       sm->first_is_protected = 0;
-      segment_manager_init_del (sm);
+      segment_manager_init_free (sm);
     }
 
-  /* If first segment manager is used by a listener */
-  if (app_wrk->first_segment_manager != APP_INVALID_SEGMENT_MANAGER_INDEX
-      && app_wrk->first_segment_manager != app_wrk->connects_seg_manager)
+  /*
+   * Half-open cleanup
+   */
+
+  for (i = 0; i < vec_len (app_wrk->half_open_table); i++)
     {
-      sm = segment_manager_get (app_wrk->first_segment_manager);
-      sm->first_is_protected = 0;
-      sm->app_wrk_index = SEGMENT_MANAGER_INVALID_APP_INDEX;
-      /* .. and has no fifos, e.g. it might be used for redirected sessions,
-       * remove it */
-      if (!segment_manager_has_fifos (sm))
-	segment_manager_del (sm);
+      if (!app_wrk->half_open_table[i])
+	continue;
+
+      /* *INDENT-OFF* */
+      hash_foreach (handle, sm_index, app_wrk->half_open_table[i], ({
+	vec_add1 (handles, handle);
+      }));
+      /* *INDENT-ON* */
+
+      for (j = 0; j < vec_len (handles); j++)
+	session_cleanup_half_open (i, handles[j]);
+
+      hash_free (app_wrk->half_open_table[i]);
+      vec_reset_length (handles);
     }
 
-  pool_put (app_workers, app_wrk);
+  vec_free (app_wrk->half_open_table);
+  vec_free (handles);
+
+  /*
+   * Detached listener segment managers cleanup
+   */
+  for (i = 0; i < vec_len (app_wrk->detached_seg_managers); i++)
+    {
+      sm = segment_manager_get (app_wrk->detached_seg_managers[i]);
+      segment_manager_init_free (sm);
+    }
+  vec_free (app_wrk->detached_seg_managers);
+  clib_spinlock_free (&app_wrk->detached_seg_managers_lock);
+
   if (CLIB_DEBUG)
     clib_memset (app_wrk, 0xfe, sizeof (*app_wrk));
+  pool_put (app_workers, app_wrk);
 }
 
 application_t *
@@ -129,20 +160,11 @@ app_worker_get_app (u32 wrk_index)
 static segment_manager_t *
 app_worker_alloc_segment_manager (app_worker_t * app_wrk)
 {
-  segment_manager_t *sm = 0;
-
-  /* If the first segment manager is not in use, don't allocate a new one */
-  if (app_wrk->first_segment_manager != APP_INVALID_SEGMENT_MANAGER_INDEX
-      && app_wrk->first_segment_manager_in_use == 0)
-    {
-      sm = segment_manager_get (app_wrk->first_segment_manager);
-      app_wrk->first_segment_manager_in_use = 1;
-      return sm;
-    }
+  segment_manager_t *sm;
 
-  sm = segment_manager_new ();
+  sm = segment_manager_alloc ();
   sm->app_wrk_index = app_wrk->wrk_index;
-
+  segment_manager_init (sm);
   return sm;
 }
 
@@ -150,22 +172,20 @@ static int
 app_worker_alloc_session_fifos (segment_manager_t * sm, session_t * s)
 {
   svm_fifo_t *rx_fifo = 0, *tx_fifo = 0;
-  u32 fifo_segment_index;
   int rv;
 
-  if ((rv = segment_manager_alloc_session_fifos (sm, &rx_fifo, &tx_fifo,
-						 &fifo_segment_index)))
+  if ((rv = segment_manager_alloc_session_fifos (sm, s->thread_index,
+						 &rx_fifo, &tx_fifo)))
     return rv;
 
-  rx_fifo->master_session_index = s->session_index;
+  rx_fifo->shr->master_session_index = s->session_index;
   rx_fifo->master_thread_index = s->thread_index;
 
-  tx_fifo->master_session_index = s->session_index;
+  tx_fifo->shr->master_session_index = s->session_index;
   tx_fifo->master_thread_index = s->thread_index;
 
   s->rx_fifo = rx_fifo;
   s->tx_fifo = tx_fifo;
-  s->svm_segment_index = fifo_segment_index;
   return 0;
 }
 
@@ -177,16 +197,17 @@ app_worker_init_listener (app_worker_t * app_wrk, session_t * ls)
   /* Allocate segment manager. All sessions derived out of a listen session
    * have fifos allocated by the same segment manager. */
   if (!(sm = app_worker_alloc_segment_manager (app_wrk)))
-    return -1;
+    return SESSION_E_ALLOC;
 
   /* Keep track of the segment manager for the listener or this worker */
   hash_set (app_wrk->listeners_table, listen_session_get_handle (ls),
 	    segment_manager_index (sm));
 
-  if (session_transport_service_type (ls) == TRANSPORT_SERVICE_CL)
+  if (transport_connection_is_cless (session_get_transport (ls)))
     {
-      if (!ls->rx_fifo && app_worker_alloc_session_fifos (sm, ls))
-	return -1;
+      if (ls->rx_fifo)
+	return SESSION_E_NOSUPPORT;
+      return app_worker_alloc_session_fifos (sm, ls);
     }
   return 0;
 }
@@ -196,9 +217,10 @@ app_worker_start_listen (app_worker_t * app_wrk,
 			 app_listener_t * app_listener)
 {
   session_t *ls;
+  int rv;
 
   if (clib_bitmap_get (app_listener->workers, app_wrk->wrk_map_index))
-    return VNET_API_ERROR_ADDRESS_IN_USE;
+    return SESSION_E_ALREADY_LISTENING;
 
   app_listener->workers = clib_bitmap_set (app_listener->workers,
 					   app_wrk->wrk_map_index, 1);
@@ -206,43 +228,87 @@ app_worker_start_listen (app_worker_t * app_wrk,
   if (app_listener->session_index != SESSION_INVALID_INDEX)
     {
       ls = session_get (app_listener->session_index, 0);
-      if (app_worker_init_listener (app_wrk, ls))
-	return -1;
+      if ((rv = app_worker_init_listener (app_wrk, ls)))
+	return rv;
     }
 
   if (app_listener->local_index != SESSION_INVALID_INDEX)
     {
       ls = session_get (app_listener->local_index, 0);
-      if (app_worker_init_listener (app_wrk, ls))
-	return -1;
+      if ((rv = app_worker_init_listener (app_wrk, ls)))
+	return rv;
     }
 
   return 0;
 }
 
+static void
+app_worker_add_detached_sm (app_worker_t * app_wrk, u32 sm_index)
+{
+  vec_add1 (app_wrk->detached_seg_managers, sm_index);
+}
+
+void
+app_worker_del_detached_sm (app_worker_t * app_wrk, u32 sm_index)
+{
+  u32 i;
+
+  clib_spinlock_lock (&app_wrk->detached_seg_managers_lock);
+  for (i = 0; i < vec_len (app_wrk->detached_seg_managers); i++)
+    {
+      if (app_wrk->detached_seg_managers[i] == sm_index)
+	{
+	  vec_del1 (app_wrk->detached_seg_managers, i);
+	  break;
+	}
+    }
+  clib_spinlock_unlock (&app_wrk->detached_seg_managers_lock);
+}
+
 static void
 app_worker_stop_listen_session (app_worker_t * app_wrk, session_t * ls)
 {
   session_handle_t handle;
   segment_manager_t *sm;
   uword *sm_indexp;
+  session_state_t *states = 0;
 
   handle = listen_session_get_handle (ls);
   sm_indexp = hash_get (app_wrk->listeners_table, handle);
   if (PREDICT_FALSE (!sm_indexp))
     return;
 
-  sm = segment_manager_get (*sm_indexp);
-  if (app_wrk->first_segment_manager == *sm_indexp)
+  /* Dealloc fifos, if any (dgram listeners) */
+  if (ls->rx_fifo)
     {
-      /* Delete sessions but don't remove segment manager */
-      app_wrk->first_segment_manager_in_use = 0;
-      segment_manager_del_sessions (sm);
+      segment_manager_dealloc_fifos (ls->rx_fifo, ls->tx_fifo);
+      ls->tx_fifo = ls->rx_fifo = 0;
     }
-  else
+
+  /* Try to cleanup segment manager */
+  sm = segment_manager_get (*sm_indexp);
+  if (sm)
     {
-      segment_manager_init_del (sm);
+      segment_manager_app_detach (sm);
+      if (!segment_manager_has_fifos (sm))
+	{
+	  /* Empty segment manager, cleanup it up */
+	  segment_manager_free (sm);
+	}
+      else
+	{
+	  /* Delete sessions in CREATED state */
+	  vec_add1 (states, SESSION_STATE_CREATED);
+	  segment_manager_del_sessions_filter (sm, states);
+	  vec_free (states);
+
+	  /* Track segment manager in case app detaches and all the
+	   * outstanding sessions need to be closed */
+	  app_worker_add_detached_sm (app_wrk, *sm_indexp);
+	  sm->flags |= SEG_MANAGER_F_DETACHED_LISTENER;
+	}
     }
+
   hash_unset (app_wrk->listeners_table, handle);
 }
 
@@ -279,11 +345,16 @@ app_worker_init_accepted (session_t * s)
   app_worker_t *app_wrk;
   segment_manager_t *sm;
   session_t *listener;
+  application_t *app;
 
-  listener = listen_session_get (s->listener_index);
+  listener = listen_session_get_from_handle (s->listener_handle);
   app_wrk = application_listener_select_worker (listener);
   s->app_wrk_index = app_wrk->wrk_index;
 
+  app = application_get (app_wrk->app_index);
+  if (app->cb_fns.fifo_tuning_callback)
+    s->flags |= SESSION_F_CUSTOM_FIFO_TUNING;
+
   sm = app_worker_get_listen_segment_manager (app_wrk, listener);
   if (app_worker_alloc_session_fifos (sm, s))
     return -1;
@@ -304,22 +375,122 @@ app_worker_init_connected (app_worker_t * app_wrk, session_t * s)
   application_t *app = application_get (app_wrk->app_index);
   segment_manager_t *sm;
 
+  if (app->cb_fns.fifo_tuning_callback)
+    s->flags |= SESSION_F_CUSTOM_FIFO_TUNING;
+
   /* Allocate fifos for session, unless the app is a builtin proxy */
-  if (!application_is_builtin_proxy (app))
-    {
-      sm = app_worker_get_connect_segment_manager (app_wrk);
-      if (app_worker_alloc_session_fifos (sm, s))
-	return -1;
-    }
-  return 0;
+  if (application_is_builtin_proxy (app))
+    return 0;
+
+  sm = app_worker_get_connect_segment_manager (app_wrk);
+  return app_worker_alloc_session_fifos (sm, s);
 }
 
 int
-app_worker_connect_notify (app_worker_t * app_wrk, session_t * s, u32 opaque)
+app_worker_connect_notify (app_worker_t * app_wrk, session_t * s,
+			   session_error_t err, u32 opaque)
 {
   application_t *app = application_get (app_wrk->app_index);
   return app->cb_fns.session_connected_callback (app_wrk->wrk_index, opaque,
-						 s, s == 0 /* is_fail */ );
+						 s, err);
+}
+
+int
+app_worker_add_half_open (app_worker_t * app_wrk, transport_proto_t tp,
+			  session_handle_t ho_handle,
+			  session_handle_t wrk_handle)
+{
+  ASSERT (vlib_get_thread_index () == 0);
+  vec_validate (app_wrk->half_open_table, tp);
+  hash_set (app_wrk->half_open_table[tp], ho_handle, wrk_handle);
+  return 0;
+}
+
+int
+app_worker_del_half_open (app_worker_t * app_wrk, transport_proto_t tp,
+			  session_handle_t ho_handle)
+{
+  ASSERT (vlib_get_thread_index () == 0);
+  hash_unset (app_wrk->half_open_table[tp], ho_handle);
+  return 0;
+}
+
+u64
+app_worker_lookup_half_open (app_worker_t * app_wrk, transport_proto_t tp,
+			     session_handle_t ho_handle)
+{
+  u64 *ho_wrk_handlep;
+
+  /* No locking because all updates are done from main thread */
+  ho_wrk_handlep = hash_get (app_wrk->half_open_table[tp], ho_handle);
+  if (!ho_wrk_handlep)
+    return SESSION_INVALID_HANDLE;
+
+  return *ho_wrk_handlep;
+}
+
+int
+app_worker_close_notify (app_worker_t * app_wrk, session_t * s)
+{
+  application_t *app = application_get (app_wrk->app_index);
+  app->cb_fns.session_disconnect_callback (s);
+  return 0;
+}
+
+int
+app_worker_transport_closed_notify (app_worker_t * app_wrk, session_t * s)
+{
+  application_t *app = application_get (app_wrk->app_index);
+  if (app->cb_fns.session_transport_closed_callback)
+    app->cb_fns.session_transport_closed_callback (s);
+  return 0;
+}
+
+int
+app_worker_reset_notify (app_worker_t * app_wrk, session_t * s)
+{
+  application_t *app = application_get (app_wrk->app_index);
+  app->cb_fns.session_reset_callback (s);
+  return 0;
+}
+
+int
+app_worker_cleanup_notify (app_worker_t * app_wrk, session_t * s,
+			   session_cleanup_ntf_t ntf)
+{
+  application_t *app = application_get (app_wrk->app_index);
+  if (app->cb_fns.session_cleanup_callback)
+    app->cb_fns.session_cleanup_callback (s, ntf);
+  return 0;
+}
+
+int
+app_worker_builtin_rx (app_worker_t * app_wrk, session_t * s)
+{
+  application_t *app = application_get (app_wrk->app_index);
+  app->cb_fns.builtin_app_rx_callback (s);
+  return 0;
+}
+
+int
+app_worker_builtin_tx (app_worker_t * app_wrk, session_t * s)
+{
+  application_t *app = application_get (app_wrk->app_index);
+
+  if (!app->cb_fns.builtin_app_tx_callback)
+    return 0;
+
+  app->cb_fns.builtin_app_tx_callback (s);
+  return 0;
+}
+
+int
+app_worker_migrate_notify (app_worker_t * app_wrk, session_t * s,
+			   session_handle_t new_sh)
+{
+  application_t *app = application_get (app_wrk->app_index);
+  app->cb_fns.session_migrate_callback (s, new_sh);
+  return 0;
 }
 
 int
@@ -342,59 +513,40 @@ app_worker_own_session (app_worker_t * app_wrk, session_t * s)
   s->rx_fifo = 0;
   s->tx_fifo = 0;
 
-  sm = app_worker_get_or_alloc_connect_segment_manager (app_wrk);
+  sm = app_worker_get_connect_segment_manager (app_wrk);
   if (app_worker_alloc_session_fifos (sm, s))
     return -1;
 
-  if (!svm_fifo_is_empty (rxf))
-    {
-      clib_memcpy_fast (s->rx_fifo->data, rxf->data, rxf->nitems);
-      s->rx_fifo->head = rxf->head;
-      s->rx_fifo->tail = rxf->tail;
-      s->rx_fifo->cursize = rxf->cursize;
-    }
+  if (!svm_fifo_is_empty_cons (rxf))
+    svm_fifo_clone (s->rx_fifo, rxf);
 
-  if (!svm_fifo_is_empty (txf))
-    {
-      clib_memcpy_fast (s->tx_fifo->data, txf->data, txf->nitems);
-      s->tx_fifo->head = txf->head;
-      s->tx_fifo->tail = txf->tail;
-      s->tx_fifo->cursize = txf->cursize;
-    }
+  if (!svm_fifo_is_empty_cons (txf))
+    svm_fifo_clone (s->tx_fifo, txf);
 
-  segment_manager_dealloc_fifos (rxf->segment_index, rxf, txf);
+  segment_manager_dealloc_fifos (rxf, txf);
 
   return 0;
 }
 
 int
-app_worker_connect_session (app_worker_t * app, session_endpoint_t * sep,
+app_worker_connect_session (app_worker_t * app_wrk, session_endpoint_t * sep,
 			    u32 api_context)
 {
   int rv;
 
-  /* Make sure we have a segment manager for connects */
-  app_worker_alloc_connects_segment_manager (app);
-
-  if ((rv = session_open (app->wrk_index, sep, api_context)))
+  if ((rv = session_open (app_wrk->wrk_index, sep, api_context)))
     return rv;
 
   return 0;
 }
 
 int
-app_worker_alloc_connects_segment_manager (app_worker_t * app_wrk)
+app_worker_session_fifo_tuning (app_worker_t * app_wrk, session_t * s,
+				svm_fifo_t * f,
+				session_ft_action_t act, u32 len)
 {
-  segment_manager_t *sm;
-
-  if (app_wrk->connects_seg_manager == APP_INVALID_SEGMENT_MANAGER_INDEX)
-    {
-      sm = app_worker_alloc_segment_manager (app_wrk);
-      if (sm == 0)
-	return -1;
-      app_wrk->connects_seg_manager = segment_manager_index (sm);
-    }
-  return 0;
+  application_t *app = application_get (app_wrk->app_index);
+  return app->cb_fns.fifo_tuning_callback (s, f, act, len);
 }
 
 segment_manager_t *
@@ -404,21 +556,13 @@ app_worker_get_connect_segment_manager (app_worker_t * app)
   return segment_manager_get (app->connects_seg_manager);
 }
 
-segment_manager_t *
-app_worker_get_or_alloc_connect_segment_manager (app_worker_t * app_wrk)
-{
-  if (app_wrk->connects_seg_manager == (u32) ~ 0)
-    app_worker_alloc_connects_segment_manager (app_wrk);
-  return segment_manager_get (app_wrk->connects_seg_manager);
-}
-
 segment_manager_t *
 app_worker_get_listen_segment_manager (app_worker_t * app,
 				       session_t * listener)
 {
   uword *smp;
   smp = hash_get (app->listeners_table, listen_session_get_handle (listener));
-  ASSERT (smp != 0);
+  ALWAYS_ASSERT (smp != 0);
   return segment_manager_get (*smp);
 }
 
@@ -438,7 +582,7 @@ app_worker_first_listener (app_worker_t * app_wrk, u8 fib_proto,
    hash_foreach (handle, sm_index, app_wrk->listeners_table, ({
      listener = listen_session_get_from_handle (handle);
      if (listener->session_type == sst
-	 && listener->enqueue_epoch != SESSION_PROXY_LISTENER_INDEX)
+	 && !(listener->flags & SESSION_F_PROXY))
        return listener;
    }));
   /* *INDENT-ON* */
@@ -461,8 +605,7 @@ app_worker_proxy_listener (app_worker_t * app_wrk, u8 fib_proto,
   /* *INDENT-OFF* */
    hash_foreach (handle, sm_index, app_wrk->listeners_table, ({
      listener = listen_session_get_from_handle (handle);
-     if (listener->session_type == sst
-	 && listener->enqueue_epoch == SESSION_PROXY_LISTENER_INDEX)
+     if (listener->session_type == sst && (listener->flags & SESSION_F_PROXY))
        return listener;
    }));
   /* *INDENT-ON* */
@@ -477,7 +620,8 @@ int
 app_worker_add_segment_notify (app_worker_t * app_wrk, u64 segment_handle)
 {
   application_t *app = application_get (app_wrk->app_index);
-  return app->cb_fns.add_segment_callback (app_wrk->api_client_index,
+
+  return app->cb_fns.add_segment_callback (app_wrk->wrk_index,
 					   segment_handle);
 }
 
@@ -485,150 +629,102 @@ int
 app_worker_del_segment_notify (app_worker_t * app_wrk, u64 segment_handle)
 {
   application_t *app = application_get (app_wrk->app_index);
-  return app->cb_fns.del_segment_callback (app_wrk->api_client_index,
+  return app->cb_fns.del_segment_callback (app_wrk->wrk_index,
 					   segment_handle);
 }
 
-u8
+static inline u8
 app_worker_application_is_builtin (app_worker_t * app_wrk)
 {
   return app_wrk->app_is_builtin;
 }
 
 static inline int
-app_enqueue_evt (svm_msg_q_t * mq, svm_msg_q_msg_t * msg, u8 lock)
-{
-  if (PREDICT_FALSE (svm_msg_q_is_full (mq)))
-    {
-      clib_warning ("evt q full");
-      svm_msg_q_free_msg (mq, msg);
-      if (lock)
-	svm_msg_q_unlock (mq);
-      return -1;
-    }
-
-  if (lock)
-    {
-      svm_msg_q_add_and_unlock (mq, msg);
-      return 0;
-    }
-
-  /* Even when not locking the ring, we must wait for queue mutex */
-  if (svm_msg_q_add (mq, msg, SVM_Q_WAIT))
-    {
-      clib_warning ("msg q add returned");
-      return -1;
-    }
-  return 0;
-}
-
-static inline int
-app_send_io_evt_rx (app_worker_t * app_wrk, session_t * s, u8 lock)
+app_send_io_evt_rx (app_worker_t * app_wrk, session_t * s)
 {
   session_event_t *evt;
   svm_msg_q_msg_t msg;
   svm_msg_q_t *mq;
 
-  if (PREDICT_FALSE (s->session_state != SESSION_STATE_READY
-		     && s->session_state != SESSION_STATE_LISTENING))
-    {
-      /* Session is closed so app will never clean up. Flush rx fifo */
-      if (s->session_state == SESSION_STATE_CLOSED)
-	svm_fifo_dequeue_drop_all (s->rx_fifo);
-      return 0;
-    }
-
   if (app_worker_application_is_builtin (app_wrk))
-    {
-      application_t *app = application_get (app_wrk->app_index);
-      return app->cb_fns.builtin_app_rx_callback (s);
-    }
+    return app_worker_builtin_rx (app_wrk, s);
 
-  if (svm_fifo_has_event (s->rx_fifo) || svm_fifo_is_empty (s->rx_fifo))
+  if (svm_fifo_has_event (s->rx_fifo))
     return 0;
 
   mq = app_wrk->event_queue;
-  if (lock)
-    svm_msg_q_lock (mq);
+  svm_msg_q_lock (mq);
+
+  if (PREDICT_FALSE (svm_msg_q_is_full (mq)))
+    {
+      clib_warning ("evt q full");
+      svm_msg_q_unlock (mq);
+      return -1;
+    }
 
   if (PREDICT_FALSE (svm_msg_q_ring_is_full (mq, SESSION_MQ_IO_EVT_RING)))
     {
       clib_warning ("evt q rings full");
-      if (lock)
-	svm_msg_q_unlock (mq);
+      svm_msg_q_unlock (mq);
       return -1;
     }
 
   msg = svm_msg_q_alloc_msg_w_ring (mq, SESSION_MQ_IO_EVT_RING);
-  ASSERT (!svm_msg_q_msg_is_invalid (&msg));
-
   evt = (session_event_t *) svm_msg_q_msg_data (mq, &msg);
-  evt->fifo = s->rx_fifo;
+  evt->session_index = s->rx_fifo->shr->client_session_index;
   evt->event_type = SESSION_IO_EVT_RX;
 
   (void) svm_fifo_set_event (s->rx_fifo);
+  svm_msg_q_add_and_unlock (mq, &msg);
 
-  if (app_enqueue_evt (mq, &msg, lock))
-    return -1;
   return 0;
 }
 
 static inline int
-app_send_io_evt_tx (app_worker_t * app_wrk, session_t * s, u8 lock)
+app_send_io_evt_tx (app_worker_t * app_wrk, session_t * s)
 {
   svm_msg_q_t *mq;
   session_event_t *evt;
   svm_msg_q_msg_t msg;
 
   if (app_worker_application_is_builtin (app_wrk))
-    return 0;
+    return app_worker_builtin_tx (app_wrk, s);
 
   mq = app_wrk->event_queue;
-  if (lock)
-    svm_msg_q_lock (mq);
+  svm_msg_q_lock (mq);
+
+  if (PREDICT_FALSE (svm_msg_q_is_full (mq)))
+    {
+      clib_warning ("evt q full");
+      svm_msg_q_unlock (mq);
+      return -1;
+    }
 
   if (PREDICT_FALSE (svm_msg_q_ring_is_full (mq, SESSION_MQ_IO_EVT_RING)))
     {
       clib_warning ("evt q rings full");
-      if (lock)
-	svm_msg_q_unlock (mq);
+      svm_msg_q_unlock (mq);
       return -1;
     }
 
   msg = svm_msg_q_alloc_msg_w_ring (mq, SESSION_MQ_IO_EVT_RING);
-  ASSERT (!svm_msg_q_msg_is_invalid (&msg));
-
   evt = (session_event_t *) svm_msg_q_msg_data (mq, &msg);
   evt->event_type = SESSION_IO_EVT_TX;
-  evt->fifo = s->tx_fifo;
+  evt->session_index = s->tx_fifo->shr->client_session_index;
 
-  return app_enqueue_evt (mq, &msg, lock);
+  svm_msg_q_add_and_unlock (mq, &msg);
+  return 0;
 }
 
 /* *INDENT-OFF* */
 typedef int (app_send_evt_handler_fn) (app_worker_t *app,
-				       session_t *s,
-				       u8 lock);
-static app_send_evt_handler_fn * const app_send_evt_handler_fns[3] = {
+				       session_t *s);
+static app_send_evt_handler_fn * const app_send_evt_handler_fns[2] = {
     app_send_io_evt_rx,
-    0,
     app_send_io_evt_tx,
 };
 /* *INDENT-ON* */
 
-/**
- * Send event to application
- *
- * Logic from queue perspective is non-blocking. If there's
- * not enough space to enqueue a message, we return.
- */
-int
-app_worker_send_event (app_worker_t * app, session_t * s, u8 evt_type)
-{
-  ASSERT (app && evt_type <= SESSION_IO_EVT_TX);
-  return app_send_evt_handler_fns[evt_type] (app, s, 0 /* lock */ );
-}
-
 /**
  * Send event to application
  *
@@ -639,7 +735,7 @@ int
 app_worker_lock_and_send_event (app_worker_t * app, session_t * s,
 				u8 evt_type)
 {
-  return app_send_evt_handler_fns[evt_type] (app, s, 1 /* lock */ );
+  return app_send_evt_handler_fns[evt_type] (app, s);
 }
 
 u8 *
@@ -656,27 +752,30 @@ format_app_worker_listener (u8 * s, va_list * args)
   if (!app_wrk)
     {
       if (verbose)
-	s = format (s, "%-40s%-25s%=10s%-15s%-15s%-10s", "Connection", "App",
+	s = format (s, "%-40s%-25s%-10s%-15s%-15s%-10s", "Connection", "App",
 		    "Wrk", "API Client", "ListenerID", "SegManager");
       else
-	s = format (s, "%-40s%-25s%=10s", "Connection", "App", "Wrk");
+	s = format (s, "%-40s%-25s%-10s", "Connection", "App", "Wrk");
 
       return s;
     }
 
   app_name = application_name_from_index (app_wrk->app_index);
   listener = listen_session_get_from_handle (handle);
-  str = format (0, "%U", format_stream_session, listener, verbose);
+  str = format (0, "%U", format_session, listener, verbose);
 
   if (verbose)
     {
-      char buf[32];
-      sprintf (buf, "%u(%u)", app_wrk->wrk_map_index, app_wrk->wrk_index);
-      s = format (s, "%-40s%-25s%=10s%-15u%-15u%-10u", str, app_name,
+      u8 *buf;
+      buf = format (0, "%u(%u)", app_wrk->wrk_map_index, app_wrk->wrk_index);
+      s = format (s, "%-40v%-25v%-10v%-15u%-15u%-10u", str, app_name,
 		  buf, app_wrk->api_client_index, handle, sm_index);
+      vec_free (buf);
     }
   else
-    s = format (s, "%-40s%-25s%=10u", str, app_name, app_wrk->wrk_map_index);
+    s = format (s, "%-40v%-25v%=10u", str, app_name, app_wrk->wrk_map_index);
+
+  vec_free (str);
 
   return s;
 }
@@ -697,63 +796,20 @@ format_app_worker (u8 * s, va_list * args)
 void
 app_worker_format_connects (app_worker_t * app_wrk, int verbose)
 {
-  svm_fifo_segment_private_t *fifo_segment;
-  vlib_main_t *vm = vlib_get_main ();
   segment_manager_t *sm;
-  const u8 *app_name;
-  u8 *s = 0;
 
   /* Header */
   if (!app_wrk)
     {
-      if (verbose)
-	vlib_cli_output (vm, "%-40s%-20s%-15s%-10s", "Connection", "App",
-			 "API Client", "SegManager");
-      else
-	vlib_cli_output (vm, "%-40s%-20s", "Connection", "App");
+      segment_manager_format_sessions (0, verbose);
       return;
     }
 
   if (app_wrk->connects_seg_manager == (u32) ~ 0)
     return;
 
-  app_name = application_name_from_index (app_wrk->app_index);
-
-  /* Across all fifo segments */
   sm = segment_manager_get (app_wrk->connects_seg_manager);
-
-  /* *INDENT-OFF* */
-  segment_manager_foreach_segment_w_lock (fifo_segment, sm, ({
-    svm_fifo_t *fifo;
-    u8 *str;
-
-    fifo = svm_fifo_segment_get_fifo_list (fifo_segment);
-    while (fifo)
-      {
-        u32 session_index, thread_index;
-        session_t *session;
-
-        session_index = fifo->master_session_index;
-        thread_index = fifo->master_thread_index;
-
-        session = session_get (session_index, thread_index);
-        str = format (0, "%U", format_stream_session, session, verbose);
-
-        if (verbose)
-          s = format (s, "%-40s%-20s%-15u%-10u", str, app_name,
-                      app_wrk->api_client_index, app_wrk->connects_seg_manager);
-        else
-          s = format (s, "%-40s%-20s", str, app_name);
-
-        vlib_cli_output (vm, "%v", s);
-        vec_reset_length (s);
-        vec_free (str);
-
-        fifo = fifo->next;
-      }
-    vec_free (s);
-  }));
-  /* *INDENT-ON* */
+  segment_manager_format_sessions (sm, verbose);
 }
 
 /*