session: cleanup use of api_client_index

Change-Id: I8a680be62ab91d2ccb144641981a635506973a49
Signed-off-by: Florin Coras <fcoras@cisco.com>

10 files changed, 98 insertions, 158 deletions

diff --git a/src/plugins/unittest/session_test.c b/src/plugins/unittest/session_test.c
index e24516668ff..c1622d17fa2 100644
--- a/src/plugins/unittest/session_test.c
+++ b/src/plugins/unittest/session_test.c
@@ -419,7 +419,7 @@ session_test_namespace (vlib_main_t * vm, unformat_input_t * input)
   u64 options[APP_OPTIONS_N_OPTIONS], dummy_secret = 1234;
   u32 server_index, server_st_index, server_local_st_index;
   u32 dummy_port = 1234, client_index, server_wrk_index;
-  u32 dummy_api_context = 4321, dummy_client_api_index = 1234;
+  u32 dummy_api_context = 4321, dummy_client_api_index = ~0;
   u32 dummy_server_api_index = ~0, sw_if_index = 0;
   session_endpoint_t server_sep = SESSION_ENDPOINT_NULL;
   session_endpoint_t client_sep = SESSION_ENDPOINT_NULL;
@@ -1493,7 +1493,7 @@ session_test_rules (vlib_main_t * vm, unformat_input_t * input)
   app_ns = app_namespace_get_from_id (ns_id);
 
   attach_args.namespace_id = ns_id;
-  attach_args.api_client_index = dummy_server_api_index - 1;
+  attach_args.api_client_index = dummy_server_api_index;
   error = vnet_application_attach (&attach_args);
   SESSION_TEST ((error == 0), "server2 attached");
   server_index2 = attach_args.app_index;
diff --git a/src/vcl/vcl_bapi.c b/src/vcl/vcl_bapi.c
index 7dd601cf737..cc494ed3b6d 100644
--- a/src/vcl/vcl_bapi.c
+++ b/src/vcl/vcl_bapi.c
@@ -131,6 +131,7 @@ vl_api_application_attach_reply_t_handler (vl_api_application_attach_reply_t *
 	return;
     }
 
+  vcm->app_index = clib_net_to_host_u32 (mp->app_index);
   vcm->app_state = STATE_APP_ATTACHED;
 }
 
@@ -429,7 +430,7 @@ vcl_send_app_worker_add_del (u8 is_add)
 
   mp->_vl_msg_id = ntohs (VL_API_APP_WORKER_ADD_DEL);
   mp->client_index = vcm->my_client_index;
-  mp->app_api_index = clib_host_to_net_u32 (vcm->main_api_client_index);
+  mp->app_index = clib_host_to_net_u32 (vcm->app_index);
   mp->context = wrk_index;
   mp->is_add = is_add;
   if (!is_add)
diff --git a/src/vcl/vcl_cfg.c b/src/vcl/vcl_cfg.c
index 3e92941d720..402bb91315f 100644
--- a/src/vcl/vcl_cfg.c
+++ b/src/vcl/vcl_cfg.c
@@ -22,7 +22,7 @@
 static vppcom_main_t _vppcom_main = {
   .debug = VPPCOM_DEBUG_INIT,
   .is_init = 0,
-  .main_api_client_index = ~0,
+  .app_index = ~0,
   .my_client_index = ~0
 };
 
diff --git a/src/vcl/vcl_private.h b/src/vcl/vcl_private.h
index 7bb0dbc5a66..0204bd5493e 100644
--- a/src/vcl/vcl_private.h
+++ b/src/vcl/vcl_private.h
@@ -282,8 +282,8 @@ typedef struct vppcom_main_t_
   /** Current pid, may be different from main_pid if forked child */
   pid_t current_pid;
 
-  /** Main process api client index. It's used by vpp to identify the app */
-  u32 main_api_client_index;
+  /** App's index in vpp. It's used by vpp to identify the app */
+  u32 app_index;
 
   /** API client handle */
   u32 my_client_index;
diff --git a/src/vcl/vppcom.c b/src/vcl/vppcom.c
index 669f04fe1e3..f20167226e8 100644
--- a/src/vcl/vppcom.c
+++ b/src/vcl/vppcom.c
@@ -773,7 +773,6 @@ vppcom_app_create (char *app_name)
 	  VERR ("couldn't connect to VPP!");
 	  return rv;
 	}
-      vcm->main_api_client_index = vcm->my_client_index;
       VDBG (0, "sending session enable");
       rv = vppcom_app_session_enable ();
       if (rv)
diff --git a/src/vnet/session/application.c b/src/vnet/session/application.c
index 72c57688e42..a70625a9bc5 100644
--- a/src/vnet/session/application.c
+++ b/src/vnet/session/application.c
@@ -97,26 +97,9 @@ app_worker_map_get (application_t * app, u32 map_index)
   return pool_elt_at_index (app->worker_maps, map_index);
 }
 
-static u8 *
-app_get_name_from_reg_index (application_t * app)
-{
-  u8 *app_name;
-
-  vl_api_registration_t *regp;
-  regp = vl_api_client_index_to_registration (app->api_client_index);
-  if (!regp)
-    app_name = format (0, "builtin-%d%c", app->app_index, 0);
-  else
-    app_name = format (0, "%s%c", regp->name, 0);
-
-  return app_name;
-}
-
 static const u8 *
 app_get_name (application_t * app)
 {
-  if (!app->name)
-    app->name = app_get_name_from_reg_index (app);
   return app->name;
 }
 
@@ -155,24 +138,6 @@ application_local_listener_session_endpoint (local_session_t * ll,
   sep->is_ip4 = ll->listener_session_type & 1;
 }
 
-int
-application_api_queue_is_full (application_t * app)
-{
-  svm_queue_t *q;
-
-  /* builtin servers are always OK */
-  if (app->api_client_index == ~0)
-    return 0;
-
-  q = vl_api_client_index_to_input_queue (app->api_client_index);
-  if (!q)
-    return 1;
-
-  if (q->cursize == q->maxsize)
-    return 1;
-  return 0;
-}
-
 /**
  * Returns app name for app-index
  */
@@ -188,7 +153,8 @@ application_name_from_index (u32 app_index)
 static void
 application_api_table_add (u32 app_index, u32 api_client_index)
 {
-  hash_set (app_main.app_by_api_client_index, api_client_index, app_index);
+  if (api_client_index != APP_INVALID_INDEX)
+    hash_set (app_main.app_by_api_client_index, api_client_index, app_index);
 }
 
 static void
@@ -198,22 +164,15 @@ application_api_table_del (u32 api_client_index)
 }
 
 static void
-application_table_add (application_t * app)
+application_name_table_add (application_t * app)
 {
-  if (app->api_client_index != APP_INVALID_INDEX)
-    hash_set (app_main.app_by_api_client_index, app->api_client_index,
-	      app->app_index);
-  else if (app->name)
-    hash_set_mem (app_main.app_by_name, app->name, app->app_index);
+  hash_set_mem (app_main.app_by_name, app->name, app->app_index);
 }
 
 static void
-application_table_del (application_t * app)
+application_name_table_del (application_t * app)
 {
-  if (app->api_client_index != APP_INVALID_INDEX)
-    hash_unset (app_main.app_by_api_client_index, app->api_client_index);
-  else if (app->name)
-    hash_unset_mem (app_main.app_by_name, app->name);
+  hash_unset_mem (app_main.app_by_name, app->name);
 }
 
 application_t *
@@ -265,12 +224,6 @@ application_get_if_valid (u32 app_index)
   return pool_elt_at_index (app_main.app_pool, app_index);
 }
 
-u32
-application_index (application_t * app)
-{
-  return app - app_main.app_pool;
-}
-
 static void
 application_verify_cb_fns (session_cb_vft_t * cb_fns)
 {
@@ -350,7 +303,6 @@ application_alloc_and_init (app_init_args_t * a)
   /* Check that the obvious things are properly set up */
   application_verify_cb_fns (a->session_cb_vft);
 
-  app->api_client_index = a->api_client_index;
   app->flags = options[APP_OPTIONS_FLAGS];
   app->cb_fns = *a->session_cb_vft;
   app->ns_index = options[APP_OPTIONS_NAMESPACE];
@@ -384,8 +336,12 @@ application_alloc_and_init (app_init_args_t * a)
   props->segment_type = seg_type;
 
   /* Add app to lookup by api_client_index table */
-  application_table_add (app);
-  a->app_index = application_index (app);
+  if (!application_is_builtin (app))
+    application_api_table_add (app->app_index, a->api_client_index);
+  else
+    application_name_table_add (app);
+
+  a->app_index = app->app_index;
 
   APP_DBG ("New app name: %v api index: %u index %u", app->name,
 	   app->api_client_index, app->app_index);
@@ -442,7 +398,8 @@ application_free (application_t * app)
   /*
    * Cleanup remaining state
    */
-  application_table_del (app);
+  if (application_is_builtin (app))
+    application_name_table_del (app);
   vec_free (app->name);
   vec_free (app->tls_cert);
   vec_free (app->tls_key);
@@ -469,7 +426,7 @@ application_detach_process (application_t * app, u32 api_client_index)
   /* *INDENT-OFF* */
   pool_foreach (wrk_map, app->worker_maps, ({
     app_wrk = app_worker_get (wrk_map->wrk_index);
-    if (app_wrk->api_index == api_client_index)
+    if (app_wrk->api_client_index == api_client_index)
       vec_add1 (wrks, app_wrk->wrk_index);
   }));
   /* *INDENT-ON* */
@@ -482,7 +439,7 @@ application_detach_process (application_t * app, u32 api_client_index)
     }
 
   args->app_index = app->app_index;
-  args->api_index = api_client_index;
+  args->api_client_index = api_client_index;
   vec_foreach (wrk_index, wrks)
   {
     app_wrk = app_worker_get (wrk_index[0]);
@@ -668,7 +625,6 @@ app_worker_alloc_and_init (application_t * app, app_worker_t ** wrk)
   app_wrk->listeners_table = hash_create (0, sizeof (u64));
   app_wrk->event_queue = segment_manager_event_queue (sm);
   app_wrk->app_is_builtin = application_is_builtin (app);
-  app_wrk->api_index = app->api_client_index;
 
   /*
    * Segment manager for local sessions
@@ -962,12 +918,8 @@ vnet_app_worker_add_del (vnet_app_worker_add_del_args_t * a)
 	return clib_error_return_code (0, rv, 0, "app wrk init: %d", rv);
 
       /* Map worker api index to the app */
-      if (a->api_index != app->api_client_index
-	  && app->api_client_index != APP_INVALID_INDEX)
-	{
-	  app_wrk->api_index = a->api_index;
-	  application_api_table_add (app->app_index, a->api_index);
-	}
+      app_wrk->api_client_index = a->api_client_index;
+      application_api_table_add (app->app_index, a->api_client_index);
 
       sm = segment_manager_get (app_wrk->first_segment_manager);
       fs = segment_manager_get_segment_w_lock (sm, 0);
@@ -987,8 +939,7 @@ vnet_app_worker_add_del (vnet_app_worker_add_del_args_t * a)
       if (!app_wrk)
 	return clib_error_return_code (0, VNET_API_ERROR_INVALID_VALUE, 0,
 				       "No worker %u", a->wrk_index);
-      if (app->api_client_index != app_wrk->api_index)
-	application_api_table_del (app_wrk->api_index);
+      application_api_table_del (app_wrk->api_client_index);
       app_worker_free (app_wrk);
       app_worker_map_free (app, wrk_map);
       if (application_n_workers (app) == 0)
@@ -1060,7 +1011,7 @@ app_worker_add_segment_notify (u32 app_wrk_index, ssvm_private_t * fs)
 {
   app_worker_t *app_wrk = app_worker_get (app_wrk_index);
   application_t *app = application_get (app_wrk->app_index);
-  return app->cb_fns.add_segment_callback (app->api_client_index, fs);
+  return app->cb_fns.add_segment_callback (app_wrk->api_client_index, fs);
 }
 
 u32
@@ -1709,7 +1660,7 @@ application_local_session_connect (app_worker_t * client_wrk,
   ls->listener_session_type = ll->session_type;
   ls->session_state = SESSION_STATE_READY;
 
-  if ((rv = server->cb_fns.add_segment_callback (server->api_client_index,
+  if ((rv = server->cb_fns.add_segment_callback (server_wrk->api_client_index,
 						 &seg->ssvm)))
     {
       clib_warning ("failed to notify server of new segment");
@@ -1763,7 +1714,7 @@ application_local_session_connect_notify (local_session_t * ls)
 
   sm = application_get_local_segment_manager_w_session (server_wrk, ls);
   seg = segment_manager_get_segment_w_lock (sm, ls->svm_segment_index);
-  if ((rv = client->cb_fns.add_segment_callback (client->api_client_index,
+  if ((rv = client->cb_fns.add_segment_callback (client_wrk->api_client_index,
 						 &seg->ssvm)))
     {
       clib_warning ("failed to notify client %u of new segment",
@@ -1819,12 +1770,12 @@ application_local_session_cleanup (app_worker_t * client_wrk,
   if (!has_transport)
     {
       application_t *server = application_get (server_wrk->app_index);
-      server->cb_fns.del_segment_callback (server->api_client_index,
+      server->cb_fns.del_segment_callback (server_wrk->api_client_index,
 					   &seg->ssvm);
       if (client_wrk)
 	{
 	  application_t *client = application_get (client_wrk->app_index);
-	  client->cb_fns.del_segment_callback (client->api_client_index,
+	  client->cb_fns.del_segment_callback (client_wrk->api_client_index,
 					       &seg->ssvm);
 	}
       segment_manager_del_segment (sm, seg);
@@ -1989,7 +1940,6 @@ format_app_worker_listener (u8 * s, va_list * args)
   u32 sm_index = va_arg (*args, u32);
   int verbose = va_arg (*args, int);
   stream_session_t *listener;
-  application_t *app;
   const u8 *app_name;
   u8 *str;
 
@@ -2004,8 +1954,7 @@ format_app_worker_listener (u8 * s, va_list * args)
       return s;
     }
 
-  app = application_get (app_wrk->app_index);
-  app_name = app_get_name (app);
+  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);
 
@@ -2014,7 +1963,7 @@ format_app_worker_listener (u8 * s, va_list * args)
       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,
-		  buf, app->api_client_index, handle, sm_index);
+		  buf, app_wrk->api_client_index, handle, sm_index);
     }
   else
     s = format (s, "%-40s%-25s%=10u", str, app_name, app_wrk->wrk_map_index);
@@ -2058,7 +2007,6 @@ app_worker_format_connects (app_worker_t * app_wrk, int verbose)
   vlib_main_t *vm = vlib_get_main ();
   segment_manager_t *sm;
   const u8 *app_name;
-  application_t *app;
   u8 *s = 0;
 
   /* Header */
@@ -2072,11 +2020,10 @@ app_worker_format_connects (app_worker_t * app_wrk, int verbose)
       return;
     }
 
-  app = application_get (app_wrk->app_index);
   if (app_wrk->connects_seg_manager == (u32) ~ 0)
     return;
 
-  app_name = app_get_name (app);
+  app_name = application_name_from_index (app_wrk->app_index);
 
   /* Across all fifo segments */
   sm = segment_manager_get (app_wrk->connects_seg_manager);
@@ -2088,28 +2035,28 @@ app_worker_format_connects (app_worker_t * app_wrk, int verbose)
 
     fifo = svm_fifo_segment_get_fifo_list (fifo_segment);
     while (fifo)
-	{
-	  u32 session_index, thread_index;
-	  stream_session_t *session;
+      {
+        u32 session_index, thread_index;
+        stream_session_t *session;
 
-	  session_index = fifo->master_session_index;
-	  thread_index = fifo->master_thread_index;
+        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);
+        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->api_client_index, app_wrk->connects_seg_manager);
-	  else
-	    s = format (s, "%-40s%-20s", str, app_name);
+        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);
+        vlib_cli_output (vm, "%v", s);
+        vec_reset_length (s);
+        vec_free (str);
 
-	  fifo = fifo->next;
-	}
+        fifo = fifo->next;
+      }
     vec_free (s);
   }));
   /* *INDENT-ON* */
@@ -2279,12 +2226,10 @@ format_application (u8 * s, va_list * args)
   if (app == 0)
     {
       if (verbose)
-	s = format (s, "%-10s%-20s%-15s%-15s%-15s%-15s%-15s", "Index", "Name",
-		    "API Client", "Namespace", "Add seg size", "Rx-f size",
-		    "Tx-f size");
+	s = format (s, "%-10s%-20s%-15s%-15s%-15s%-15s", "Index", "Name",
+		    "Namespace", "Add seg size", "Rx-f size", "Tx-f size");
       else
-	s = format (s, "%-10s%-20s%-15s%-40s", "Index", "Name", "API Client",
-		    "Namespace");
+	s = format (s, "%-10s%-20s%-40s", "Index", "Name", "Namespace");
       return s;
     }
 
@@ -2292,14 +2237,13 @@ format_application (u8 * s, va_list * args)
   app_ns_name = app_namespace_id_from_index (app->ns_index);
   props = application_segment_manager_properties (app);
   if (verbose)
-    s = format (s, "%-10u%-20s%-15d%-15u%-15U%-15U%-15U", app->app_index,
-		app_name, app->api_client_index, app->ns_index,
+    s = format (s, "%-10u%-20s%-15u%-15U%-15U%-15U", app->app_index,
+		app_name, app->ns_index,
 		format_memory_size, props->add_segment_size,
 		format_memory_size, props->rx_fifo_size, format_memory_size,
 		props->tx_fifo_size);
   else
-    s = format (s, "%-10u%-20s%-15d%-40s", app->app_index, app_name,
-		app->api_client_index, app_ns_name);
+    s = format (s, "%-10u%-20s%-40s", app->app_index, app_name, app_ns_name);
   return s;
 }
 
diff --git a/src/vnet/session/application.h b/src/vnet/session/application.h
index 9c68433d5e9..596b197a0f4 100644
--- a/src/vnet/session/application.h
+++ b/src/vnet/session/application.h
@@ -102,7 +102,7 @@ typedef struct app_worker_
   uword *local_connects;
 
   /** API index for the worker. Needed for multi-process apps */
-  u32 api_index;
+  u32 api_client_index;
 
   u8 app_is_builtin;
 } app_worker_t;
@@ -124,10 +124,6 @@ typedef struct application_
   /** App index in app pool */
   u32 app_index;
 
-  /** Binary API connection index of app process that created the app,
-   *  ~0 if internal */
-  u32 api_client_index;
-
   /** Flags */
   u32 flags;
 
@@ -214,7 +210,7 @@ typedef struct _vnet_app_worker_add_del_args
 {
   u32 app_index;		/**< App for which a new worker is requested */
   u32 wrk_index;		/**< Index to delete or return value if add */
-  u32 api_index;		/**< Binary API client index */
+  u32 api_client_index;		/**< Binary API client index */
   ssvm_private_t *segment;	/**< First segment in segment manager */
   svm_msg_q_t *evt_q;		/**< Worker message queue */
   u8 is_add;			/**< Flag set if addition */
@@ -261,14 +257,11 @@ application_t *application_get (u32 index);
 application_t *application_get_if_valid (u32 index);
 application_t *application_lookup (u32 api_client_index);
 application_t *application_lookup_name (const u8 * name);
-u32 application_index (application_t * app);
 app_worker_t *application_get_worker (application_t * app, u32 wrk_index);
 app_worker_t *application_get_default_worker (application_t * app);
 app_worker_t *application_listener_select_worker (stream_session_t * ls,
 						  u8 is_local);
 
-int application_api_queue_is_full (application_t * app);
-
 int application_is_proxy (application_t * app);
 int application_is_builtin (application_t * app);
 int application_is_builtin_proxy (application_t * app);
diff --git a/src/vnet/session/application_interface.c b/src/vnet/session/application_interface.c
index 3cd8c2f5eb3..2a09909dbef 100644
--- a/src/vnet/session/application_interface.c
+++ b/src/vnet/session/application_interface.c
@@ -496,11 +496,21 @@ vnet_application_attach (vnet_app_attach_args_t * a)
   app_worker_t *app_wrk;
   segment_manager_t *sm;
   u32 app_ns_index = 0;
+  u8 *app_name = 0;
   u64 secret;
   int rv;
 
   if (a->api_client_index != APP_INVALID_INDEX)
-    app = application_lookup (a->api_client_index);
+    {
+      app = application_lookup (a->api_client_index);
+      if (!app)
+	{
+	  vl_api_registration_t *regp;
+	  regp = vl_api_client_index_to_registration (a->api_client_index);
+	  app_name = format (0, "%s%c", regp->name, 0);
+	  a->name = app_name;
+	}
+    }
   else if (a->name)
     app = application_lookup_name (a->name);
   else
@@ -524,6 +534,7 @@ vnet_application_attach (vnet_app_attach_args_t * a)
     return clib_error_return_code (0, rv, 0, "app default wrk init: %d", rv);
 
   a->app_evt_q = app_wrk->event_queue;
+  app_wrk->api_client_index = a->api_client_index;
   sm = segment_manager_get (app_wrk->first_segment_manager);
   fs = segment_manager_get_segment_w_lock (sm, 0);
 
@@ -534,7 +545,7 @@ vnet_application_attach (vnet_app_attach_args_t * a)
   a->segment = &fs->ssvm;
 
   segment_manager_segment_reader_unlock (sm);
-
+  vec_free (app_name);
   return 0;
 }
 
diff --git a/src/vnet/session/session.api b/src/vnet/session/session.api
index 64b82051da2..eced1d47770 100644
--- a/src/vnet/session/session.api
+++ b/src/vnet/session/session.api
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-option version = "1.2.1";
+option version = "1.3.0";
 
 /** \brief client->vpp, attach application to session layer
     @param client_index - opaque cookie to identify the sender
@@ -44,6 +44,7 @@ option version = "1.2.1";
     @param segment_size - size of first shm segment
     @param segment_name_length - length of segment name 
     @param segment_name - name of segment client needs to attach to
+    @param app_index - index of the newly created app
 */
 define application_attach_reply {
     u32 context;
@@ -54,6 +55,7 @@ define application_attach_reply {
     u32 segment_size;
     u8 segment_name_length;
     u8 segment_name[128];
+    u32 app_index;
 };
 
 /** \brief Application add TLS certificate
@@ -437,7 +439,7 @@ autoreply define app_cut_through_registration_add
     @param client_index - opaque cookie to identify the sender
                           client to vpp direction only
     @param context - sender context, to match reply w/ request
-    @param app_api_index - explicit client api index
+    @param app_index - application index
     @param wrk_index - worker index, if a delete
     @param is_add - set if an add
 */
@@ -445,7 +447,7 @@ define app_worker_add_del
 {
   u32 client_index;
   u32 context;
-  u32 app_api_index;
+  u32 app_index;
   u32 wrk_index;
   u8 is_add;
 };
diff --git a/src/vnet/session/session_api.c b/src/vnet/session/session_api.c
index 58877010326..d960792ee86 100755
--- a/src/vnet/session/session_api.c
+++ b/src/vnet/session/session_api.c
@@ -207,10 +207,11 @@ send_session_accept_callback (stream_session_t * s)
   application_t *server;
 
   server = application_get (server_wrk->app_index);
-  reg = vl_mem_api_client_index_to_registration (server->api_client_index);
+  reg =
+    vl_mem_api_client_index_to_registration (server_wrk->api_client_index);
   if (!reg)
     {
-      clib_warning ("no registration: %u", server->api_client_index);
+      clib_warning ("no registration: %u", server_wrk->api_client_index);
       return -1;
     }
 
@@ -284,13 +285,11 @@ send_session_disconnect_callback (stream_session_t * s)
   app_worker_t *app_wrk = app_worker_get (s->app_wrk_index);
   vl_api_disconnect_session_t *mp;
   vl_api_registration_t *reg;
-  application_t *app;
 
-  app = application_get (app_wrk->app_index);
-  reg = vl_mem_api_client_index_to_registration (app->api_client_index);
+  reg = vl_mem_api_client_index_to_registration (app_wrk->api_client_index);
   if (!reg)
     {
-      clib_warning ("no registration: %u", app->api_client_index);
+      clib_warning ("no registration: %u", app_wrk->api_client_index);
       return;
     }
 
@@ -298,7 +297,7 @@ send_session_disconnect_callback (stream_session_t * s)
   clib_memset (mp, 0, sizeof (*mp));
   mp->_vl_msg_id = clib_host_to_net_u16 (VL_API_DISCONNECT_SESSION);
   mp->handle = session_handle (s);
-  mp->context = app->api_client_index;
+  mp->context = app_wrk->api_client_index;
   vl_msg_api_send_shmem (reg->vl_input_queue, (u8 *) & mp);
 }
 
@@ -308,13 +307,11 @@ send_session_reset_callback (stream_session_t * s)
   app_worker_t *app_wrk = app_worker_get (s->app_wrk_index);
   vl_api_registration_t *reg;
   vl_api_reset_session_t *mp;
-  application_t *app;
 
-  app = application_get (app_wrk->app_index);
-  reg = vl_mem_api_client_index_to_registration (app->api_client_index);
+  reg = vl_mem_api_client_index_to_registration (app_wrk->api_client_index);
   if (!reg)
     {
-      clib_warning ("no registration: %u", app->api_client_index);
+      clib_warning ("no registration: %u", app_wrk->api_client_index);
       return;
     }
 
@@ -334,14 +331,12 @@ send_session_connected_callback (u32 app_wrk_index, u32 api_context,
   vl_api_registration_t *reg;
   svm_msg_q_t *vpp_queue;
   app_worker_t *app_wrk;
-  application_t *app;
 
   app_wrk = app_worker_get (app_wrk_index);
-  app = application_get (app_wrk->app_index);
-  reg = vl_mem_api_client_index_to_registration (app->api_client_index);
+  reg = vl_mem_api_client_index_to_registration (app_wrk->api_client_index);
   if (!reg)
     {
-      clib_warning ("no registration: %u", app->api_client_index);
+      clib_warning ("no registration: %u", app_wrk->api_client_index);
       return -1;
     }
 
@@ -467,7 +462,7 @@ mq_send_session_accepted_cb (stream_session_t * s)
       local_session_t *ll;
       u8 main_thread = vlib_num_workers ()? 1 : 0;
 
-      send_app_cut_through_registration_add (app->api_client_index,
+      send_app_cut_through_registration_add (app_wrk->api_client_index,
 					     app_wrk->wrk_map_index,
 					     ls->server_evt_q,
 					     ls->client_evt_q);
@@ -512,9 +507,7 @@ mq_send_session_disconnected_cb (stream_session_t * s)
   session_disconnected_msg_t *mp;
   svm_msg_q_t *app_mq;
   session_event_t *evt;
-  application_t *app;
 
-  app = application_get (app_wrk->app_index);
   app_mq = app_wrk->event_queue;
   if (mq_try_lock_and_alloc_msg (app_mq, msg))
     return;
@@ -523,7 +516,7 @@ mq_send_session_disconnected_cb (stream_session_t * s)
   evt->event_type = SESSION_CTRL_EVT_DISCONNECTED;
   mp = (session_disconnected_msg_t *) evt->data;
   mp->handle = session_handle (s);
-  mp->context = app->api_client_index;
+  mp->context = app_wrk->api_client_index;
   svm_msg_q_add_and_unlock (app_mq, msg);
 }
 
@@ -536,9 +529,7 @@ mq_send_local_session_disconnected_cb (u32 app_wrk_index,
   session_disconnected_msg_t *mp;
   svm_msg_q_t *app_mq;
   session_event_t *evt;
-  application_t *app;
 
-  app = application_get (app_wrk->app_index);
   app_mq = app_wrk->event_queue;
   if (mq_try_lock_and_alloc_msg (app_mq, msg))
     return;
@@ -547,7 +538,7 @@ mq_send_local_session_disconnected_cb (u32 app_wrk_index,
   evt->event_type = SESSION_CTRL_EVT_DISCONNECTED;
   mp = (session_disconnected_msg_t *) evt->data;
   mp->handle = application_local_session_handle (ls);
-  mp->context = app->api_client_index;
+  mp->context = app_wrk->api_client_index;
   svm_msg_q_add_and_unlock (app_mq, msg);
 }
 
@@ -581,15 +572,13 @@ mq_send_session_connected_cb (u32 app_wrk_index, u32 api_context,
   transport_connection_t *tc;
   app_worker_t *app_wrk;
   session_event_t *evt;
-  application_t *app;
 
   app_wrk = app_worker_get (app_wrk_index);
-  app = application_get (app_wrk->app_index);
   app_mq = app_wrk->event_queue;
   if (!app_mq)
     {
-      clib_warning ("app %u with api index: %u not attached", app->app_index,
-		    app->api_client_index);
+      clib_warning ("app %u with api index: %u not attached",
+		    app_wrk->app_index, app_wrk->api_client_index);
       return -1;
     }
 
@@ -627,7 +616,7 @@ mq_send_session_connected_cb (u32 app_wrk_index, u32 api_context,
       local_session_t *ls = (local_session_t *) s;
       u8 main_thread = vlib_num_workers ()? 1 : 0;
 
-      send_app_cut_through_registration_add (app->api_client_index,
+      send_app_cut_through_registration_add (app_wrk->api_client_index,
 					     app_wrk->wrk_map_index,
 					     ls->client_evt_q,
 					     ls->server_evt_q);
@@ -668,8 +657,8 @@ mq_send_session_bound_cb (u32 app_wrk_index, u32 api_context,
   app_mq = app_wrk->event_queue;
   if (!app_mq)
     {
-      clib_warning ("app %u with api index: %u not attached", app->app_index,
-		    app->api_client_index);
+      clib_warning ("app %u with api index: %u not attached",
+		    app_wrk->app_index, app_wrk->api_client_index);
       return -1;
     }
 
@@ -820,6 +809,7 @@ done:
     if (!rv)
       {
 	segp = a->segment;
+	rmp->app_index = clib_host_to_net_u32 (a->app_index);
 	rmp->segment_name_length = 0;
 	rmp->segment_size = segp->ssvm_size;
 	if (vec_len (segp->name))
@@ -1350,7 +1340,7 @@ vl_api_app_worker_add_del_t_handler (vl_api_app_worker_add_del_t * mp)
   if (!reg)
     return;
 
-  app = application_lookup (clib_net_to_host_u32 (mp->app_api_index));
+  app = application_get_if_valid (clib_net_to_host_u32 (mp->app_index));
   if (!app)
     {
       rv = VNET_API_ERROR_INVALID_VALUE;
@@ -1360,7 +1350,7 @@ vl_api_app_worker_add_del_t_handler (vl_api_app_worker_add_del_t * mp)
   vnet_app_worker_add_del_args_t args = {
     .app_index = app->app_index,
     .wrk_index = clib_net_to_host_u32 (mp->wrk_index),
-    .api_index = mp->client_index,
+    .api_client_index = mp->client_index,
     .is_add = mp->is_add
   };
   error = vnet_app_worker_add_del (&args);