X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fvcl%2Fvppcom.c;h=69d9285ff7e044de8728363d1ac8337e50be3695;hb=8ac1d6d05;hp=1991e3e72774ea05bcf0cb290f50793e0b54d04d;hpb=145987776f57de20e9724d58fe28796d40ffebfa;p=vpp.git

diff --git a/src/vcl/vppcom.c b/src/vcl/vppcom.c
index 1991e3e7277..69d9285ff7e 100644
--- a/src/vcl/vppcom.c
+++ b/src/vcl/vppcom.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Copyright (c) 2017-2019 Cisco and/or its affiliates.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this
  * You may obtain a copy of the License at:
@@ -15,58 +15,52 @@
 
 #include <stdio.h>
 #include <stdlib.h>
-#include <svm/svm_fifo_segment.h>
 #include <vcl/vppcom.h>
-#include <vcl/vcl_event.h>
 #include <vcl/vcl_debug.h>
 #include <vcl/vcl_private.h>
+#include <svm/fifo_segment.h>
 
 __thread uword __vcl_worker_index = ~0;
 
-static u8 not_ready;
-
-void
-sigsegv_signal (int signum)
+static int
+vcl_wait_for_segment (u64 segment_handle)
 {
-  not_ready = 1;
-}
+  vcl_worker_t *wrk = vcl_worker_get_current ();
+  u32 wait_for_seconds = 10, segment_index;
+  f64 timeout;
 
-static void
-vcl_wait_for_memory (void *mem)
-{
-  u8 __clib_unused test;
-  if (vcm->mounting_segment)
-    {
-      while (vcm->mounting_segment)
-	;
-      return;
-    }
-  if (1 || vcm->debug)
-    {
-      usleep (1e5);
-      return;
-    }
-  if (signal (SIGSEGV, sigsegv_signal))
+  if (segment_handle == VCL_INVALID_SEGMENT_HANDLE)
+    return 0;
+
+  timeout = clib_time_now (&wrk->clib_time) + wait_for_seconds;
+  while (clib_time_now (&wrk->clib_time) < timeout)
     {
-      perror ("signal()");
-      return;
+      segment_index = vcl_segment_table_lookup (segment_handle);
+      if (segment_index != VCL_INVALID_SEGMENT_INDEX)
+	return 0;
+      usleep (10);
     }
-  not_ready = 0;
+  return 1;
+}
 
-again:
-  test = *(u8 *) mem;
-  if (not_ready)
+static inline int
+vcl_mq_dequeue_batch (vcl_worker_t * wrk, svm_msg_q_t * mq, u32 n_max_msg)
+{
+  svm_msg_q_msg_t *msg;
+  u32 n_msgs;
+  int i;
+
+  n_msgs = clib_min (svm_msg_q_size (mq), n_max_msg);
+  for (i = 0; i < n_msgs; i++)
     {
-      not_ready = 0;
-      usleep (1);
-      goto again;
+      vec_add2 (wrk->mq_msg_vector, msg, 1);
+      svm_msg_q_sub_w_lock (mq, msg);
     }
-
-  signal (SIGSEGV, SIG_DFL);
+  return n_msgs;
 }
 
 const char *
-vppcom_session_state_str (session_state_t state)
+vppcom_session_state_str (vcl_session_state_t state)
 {
   char *st;
 
@@ -88,8 +82,8 @@ vppcom_session_state_str (session_state_t state)
       st = "STATE_ACCEPT";
       break;
 
-    case STATE_CLOSE_ON_EMPTY:
-      st = "STATE_CLOSE_ON_EMPTY";
+    case STATE_VPP_CLOSING:
+      st = "STATE_VPP_CLOSING";
       break;
 
     case STATE_DISCONNECT:
@@ -100,6 +94,14 @@ vppcom_session_state_str (session_state_t state)
       st = "STATE_FAILED";
       break;
 
+    case STATE_UPDATED:
+      st = "STATE_UPDATED";
+      break;
+
+    case STATE_LISTEN_NO_MQ:
+      st = "STATE_LISTEN_NO_MQ";
+      break;
+
     default:
       st = "UNKNOWN_STATE";
       break;
@@ -196,15 +198,6 @@ format_ip46_address (u8 * s, va_list * args)
  */
 
 
-static svm_msg_q_t *
-vcl_session_vpp_evt_q (vcl_worker_t * wrk, vcl_session_t * s)
-{
-  if (vcl_session_is_ct (s))
-    return wrk->vpp_event_queues[0];
-  else
-    return wrk->vpp_event_queues[s->tx_fifo->master_thread_index];
-}
-
 static void
 vcl_send_session_accepted_reply (svm_msg_q_t * mq, u32 context,
 				 session_handle_t handle, int retval)
@@ -248,8 +241,27 @@ vcl_send_session_reset_reply (svm_msg_q_t * mq, u32 context,
   app_send_ctrl_evt_to_vpp (mq, app_evt);
 }
 
+void
+vcl_send_session_worker_update (vcl_worker_t * wrk, vcl_session_t * s,
+				u32 wrk_index)
+{
+  app_session_evt_t _app_evt, *app_evt = &_app_evt;
+  session_worker_update_msg_t *mp;
+  svm_msg_q_t *mq;
+
+  mq = vcl_session_vpp_evt_q (wrk, s);
+  app_alloc_ctrl_evt_to_vpp (mq, app_evt, SESSION_CTRL_EVT_WORKER_UPDATE);
+  mp = (session_worker_update_msg_t *) app_evt->evt->data;
+  mp->client_index = wrk->my_client_index;
+  mp->handle = s->vpp_handle;
+  mp->req_wrk_index = wrk->vpp_wrk_index;
+  mp->wrk_index = wrk_index;
+  app_send_ctrl_evt_to_vpp (mq, app_evt);
+}
+
 static u32
-vcl_session_accepted_handler (vcl_worker_t * wrk, session_accepted_msg_t * mp)
+vcl_session_accepted_handler (vcl_worker_t * wrk, session_accepted_msg_t * mp,
+			      u32 ls_index)
 {
   vcl_session_t *session, *listen_session;
   svm_fifo_t *rx_fifo, *tx_fifo;
@@ -258,74 +270,70 @@ vcl_session_accepted_handler (vcl_worker_t * wrk, session_accepted_msg_t * mp)
 
   session = vcl_session_alloc (wrk);
 
-  listen_session = vcl_session_table_lookup_listener (wrk,
-						      mp->listener_handle);
-  if (!listen_session)
+  listen_session = vcl_session_get (wrk, ls_index);
+  if (listen_session->vpp_handle != mp->listener_handle)
     {
-      svm_msg_q_t *evt_q;
-      evt_q = uword_to_pointer (mp->vpp_event_queue_address, svm_msg_q_t *);
-      clib_warning ("VCL<%d>: ERROR: couldn't find listen session: "
-		    "unknown vpp listener handle %llx",
-		    getpid (), mp->listener_handle);
-      vcl_send_session_accepted_reply (evt_q, mp->context, mp->handle,
-				       VNET_API_ERROR_INVALID_ARGUMENT);
-      vcl_session_free (wrk, session);
-      return VCL_INVALID_SESSION_INDEX;
+      VDBG (0, "ERROR: listener handle %lu does not match session %u",
+	    mp->listener_handle, ls_index);
+      goto error;
     }
 
-  rx_fifo = uword_to_pointer (mp->server_rx_fifo, svm_fifo_t *);
-  tx_fifo = uword_to_pointer (mp->server_tx_fifo, svm_fifo_t *);
-
-  if (mp->server_event_queue_address)
+  if (vcl_wait_for_segment (mp->segment_handle))
     {
-      session->vpp_evt_q = uword_to_pointer (mp->client_event_queue_address,
-					     svm_msg_q_t *);
-      session->our_evt_q = uword_to_pointer (mp->server_event_queue_address,
-					     svm_msg_q_t *);
-      vcl_wait_for_memory (session->vpp_evt_q);
-      rx_fifo->master_session_index = session->session_index;
-      tx_fifo->master_session_index = session->session_index;
-      vec_validate (wrk->vpp_event_queues, 0);
-      evt_q = uword_to_pointer (mp->vpp_event_queue_address, svm_msg_q_t *);
-      wrk->vpp_event_queues[0] = evt_q;
+      VDBG (0, "ERROR: segment for session %u couldn't be mounted!",
+	    session->session_index);
+      goto error;
     }
-  else
-    {
-      session->vpp_evt_q = uword_to_pointer (mp->vpp_event_queue_address,
-					     svm_msg_q_t *);
-      rx_fifo->client_session_index = session->session_index;
-      tx_fifo->client_session_index = session->session_index;
 
-      vpp_wrk_index = tx_fifo->master_thread_index;
-      vec_validate (wrk->vpp_event_queues, vpp_wrk_index);
-      wrk->vpp_event_queues[vpp_wrk_index] = session->vpp_evt_q;
-    }
+  rx_fifo = uword_to_pointer (mp->server_rx_fifo, svm_fifo_t *);
+  tx_fifo = uword_to_pointer (mp->server_tx_fifo, svm_fifo_t *);
+  session->vpp_evt_q = uword_to_pointer (mp->vpp_event_queue_address,
+					 svm_msg_q_t *);
+  rx_fifo->client_session_index = session->session_index;
+  tx_fifo->client_session_index = session->session_index;
+  rx_fifo->client_thread_index = vcl_get_worker_index ();
+  tx_fifo->client_thread_index = vcl_get_worker_index ();
+  vpp_wrk_index = tx_fifo->master_thread_index;
+  vec_validate (wrk->vpp_event_queues, vpp_wrk_index);
+  wrk->vpp_event_queues[vpp_wrk_index] = session->vpp_evt_q;
 
   session->vpp_handle = mp->handle;
-  session->client_context = mp->context;
+  session->vpp_thread_index = rx_fifo->master_thread_index;
   session->rx_fifo = rx_fifo;
   session->tx_fifo = tx_fifo;
 
   session->session_state = STATE_ACCEPT;
-  session->transport.rmt_port = mp->port;
-  session->transport.is_ip4 = mp->is_ip4;
-  clib_memcpy (&session->transport.rmt_ip, mp->ip, sizeof (ip46_address_t));
+  session->transport.rmt_port = mp->rmt.port;
+  session->transport.is_ip4 = mp->rmt.is_ip4;
+  clib_memcpy_fast (&session->transport.rmt_ip, &mp->rmt.ip,
+		    sizeof (ip46_address_t));
 
   vcl_session_table_add_vpp_handle (wrk, mp->handle, session->session_index);
   session->transport.lcl_port = listen_session->transport.lcl_port;
   session->transport.lcl_ip = listen_session->transport.lcl_ip;
   session->session_type = listen_session->session_type;
-  session->is_dgram = session->session_type == VPPCOM_PROTO_UDP;
-
-  VDBG (1, "VCL<%d>: vpp handle 0x%llx, sid %u: client accept request from %s"
-	" address %U port %d queue %p!", getpid (), mp->handle,
-	session->session_index,
-	mp->is_ip4 ? "IPv4" : "IPv6", format_ip46_address, &mp->ip,
-	mp->is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
-	clib_net_to_host_u16 (mp->port), session->vpp_evt_q);
+  session->is_dgram = vcl_proto_is_dgram (session->session_type);
+  session->listener_index = listen_session->session_index;
+  listen_session->n_accepted_sessions++;
+
+  VDBG (1, "session %u [0x%llx]: client accept request from %s address %U"
+	" port %d queue %p!", session->session_index, mp->handle,
+	mp->rmt.is_ip4 ? "IPv4" : "IPv6", format_ip46_address, &mp->rmt.ip,
+	mp->rmt.is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
+	clib_net_to_host_u16 (mp->rmt.port), session->vpp_evt_q);
   vcl_evt (VCL_EVT_ACCEPT, session, listen_session, session_index);
 
+  vcl_send_session_accepted_reply (session->vpp_evt_q, mp->context,
+				   session->vpp_handle, 0);
+
   return session->session_index;
+
+error:
+  evt_q = uword_to_pointer (mp->vpp_event_queue_address, svm_msg_q_t *);
+  vcl_send_session_accepted_reply (evt_q, mp->context, mp->handle,
+				   VNET_API_ERROR_INVALID_ARGUMENT);
+  vcl_session_free (wrk, session);
+  return VCL_INVALID_SESSION_INDEX;
 }
 
 static u32
@@ -335,22 +343,19 @@ vcl_session_connected_handler (vcl_worker_t * wrk,
   u32 session_index, vpp_wrk_index;
   svm_fifo_t *rx_fifo, *tx_fifo;
   vcl_session_t *session = 0;
-  svm_msg_q_t *evt_q;
 
   session_index = mp->context;
   session = vcl_session_get (wrk, session_index);
   if (!session)
     {
-      clib_warning ("[%s] ERROR: vpp handle 0x%llx, sid %u: "
-		    "Invalid session index (%u)!",
-		    getpid (), mp->handle, session_index);
+      VDBG (0, "ERROR: vpp handle 0x%llx has no session index (%u)!",
+	    mp->handle, session_index);
       return VCL_INVALID_SESSION_INDEX;
     }
   if (mp->retval)
     {
-      clib_warning ("VCL<%d>: ERROR: sid %u: connect failed! %U", getpid (),
-		    mp->handle, session_index, format_api_error,
-		    ntohl (mp->retval));
+      VDBG (0, "ERROR: session index %u: connect failed! %U",
+	    session_index, format_api_error, ntohl (mp->retval));
       session->session_state = STATE_FAILED;
       session->vpp_handle = mp->handle;
       return session_index;
@@ -358,50 +363,76 @@ vcl_session_connected_handler (vcl_worker_t * wrk,
 
   rx_fifo = uword_to_pointer (mp->server_rx_fifo, svm_fifo_t *);
   tx_fifo = uword_to_pointer (mp->server_tx_fifo, svm_fifo_t *);
-  vcl_wait_for_memory (rx_fifo);
+  if (vcl_wait_for_segment (mp->segment_handle))
+    {
+      VDBG (0, "segment for session %u couldn't be mounted!",
+	    session->session_index);
+      session->session_state = STATE_FAILED;
+      return VCL_INVALID_SESSION_INDEX;
+    }
+
   rx_fifo->client_session_index = session_index;
   tx_fifo->client_session_index = session_index;
+  rx_fifo->client_thread_index = vcl_get_worker_index ();
+  tx_fifo->client_thread_index = vcl_get_worker_index ();
 
-  if (mp->client_event_queue_address)
-    {
-      session->vpp_evt_q = uword_to_pointer (mp->server_event_queue_address,
-					     svm_msg_q_t *);
-      session->our_evt_q = uword_to_pointer (mp->client_event_queue_address,
-					     svm_msg_q_t *);
+  session->vpp_evt_q = uword_to_pointer (mp->vpp_event_queue_address,
+					 svm_msg_q_t *);
+  vpp_wrk_index = tx_fifo->master_thread_index;
+  vec_validate (wrk->vpp_event_queues, vpp_wrk_index);
+  wrk->vpp_event_queues[vpp_wrk_index] = session->vpp_evt_q;
 
-      vec_validate (wrk->vpp_event_queues, 0);
-      evt_q = uword_to_pointer (mp->vpp_event_queue_address, svm_msg_q_t *);
-      wrk->vpp_event_queues[0] = evt_q;
-    }
-  else
+  if (mp->ct_rx_fifo)
     {
-      session->vpp_evt_q = uword_to_pointer (mp->vpp_event_queue_address,
-					     svm_msg_q_t *);
-      vpp_wrk_index = tx_fifo->master_thread_index;
-      vec_validate (wrk->vpp_event_queues, vpp_wrk_index);
-      wrk->vpp_event_queues[vpp_wrk_index] = session->vpp_evt_q;
+      session->ct_rx_fifo = uword_to_pointer (mp->ct_rx_fifo, svm_fifo_t *);
+      session->ct_tx_fifo = uword_to_pointer (mp->ct_tx_fifo, svm_fifo_t *);
+      if (vcl_wait_for_segment (mp->ct_segment_handle))
+	{
+	  VDBG (0, "ct segment for session %u couldn't be mounted!",
+		session->session_index);
+	  session->session_state = STATE_FAILED;
+	  return VCL_INVALID_SESSION_INDEX;
+	}
     }
 
   session->rx_fifo = rx_fifo;
   session->tx_fifo = tx_fifo;
   session->vpp_handle = mp->handle;
-  session->transport.is_ip4 = mp->is_ip4;
-  clib_memcpy (&session->transport.lcl_ip, mp->lcl_ip,
-	       sizeof (session->transport.lcl_ip));
-  session->transport.lcl_port = mp->lcl_port;
+  session->vpp_thread_index = rx_fifo->master_thread_index;
+  session->transport.is_ip4 = mp->lcl.is_ip4;
+  clib_memcpy_fast (&session->transport.lcl_ip, &mp->lcl.ip,
+		    sizeof (session->transport.lcl_ip));
+  session->transport.lcl_port = mp->lcl.port;
   session->session_state = STATE_CONNECT;
 
   /* Add it to lookup table */
-  hash_set (wrk->session_index_by_vpp_handles, mp->handle, session_index);
+  vcl_session_table_add_vpp_handle (wrk, mp->handle, session_index);
 
-  VDBG (1, "VCL<%d>: vpp handle 0x%llx, sid %u: connect succeeded! "
-	"session_rx_fifo %p, refcnt %d, session_tx_fifo %p, refcnt %d",
-	getpid (), mp->handle, session_index, session->rx_fifo,
+  VDBG (1, "session %u [0x%llx] connected! rx_fifo %p, refcnt %d, tx_fifo %p,"
+	" refcnt %d", session_index, mp->handle, session->rx_fifo,
 	session->rx_fifo->refcnt, session->tx_fifo, session->tx_fifo->refcnt);
 
   return session_index;
 }
 
+static int
+vcl_flag_accepted_session (vcl_session_t * session, u64 handle, u32 flags)
+{
+  vcl_session_msg_t *accepted_msg;
+  int i;
+
+  for (i = 0; i < vec_len (session->accept_evts_fifo); i++)
+    {
+      accepted_msg = &session->accept_evts_fifo[i];
+      if (accepted_msg->accepted_msg.handle == handle)
+	{
+	  accepted_msg->flags |= flags;
+	  return 1;
+	}
+    }
+  return 0;
+}
+
 static u32
 vcl_session_reset_handler (vcl_worker_t * wrk,
 			   session_reset_msg_t * reset_msg)
@@ -416,10 +447,19 @@ vcl_session_reset_handler (vcl_worker_t * wrk,
       VDBG (0, "request to reset unknown handle 0x%llx", reset_msg->handle);
       return VCL_INVALID_SESSION_INDEX;
     }
-  session->session_state = STATE_CLOSE_ON_EMPTY;
-  VDBG (0, "reset handle 0x%llx, sid %u ", reset_msg->handle, sid);
-  vcl_send_session_reset_reply (vcl_session_vpp_evt_q (wrk, session),
-				vcm->my_client_index, reset_msg->handle, 0);
+
+  /* Caught a reset before actually accepting the session */
+  if (session->session_state == STATE_LISTEN)
+    {
+
+      if (!vcl_flag_accepted_session (session, reset_msg->handle,
+				      VCL_ACCEPTED_F_RESET))
+	VDBG (0, "session was not accepted!");
+      return VCL_INVALID_SESSION_INDEX;
+    }
+
+  session->session_state = STATE_DISCONNECT;
+  VDBG (0, "reset session %u [0x%llx]", sid, reset_msg->handle);
   return sid;
 }
 
@@ -432,8 +472,8 @@ vcl_session_bound_handler (vcl_worker_t * wrk, session_bound_msg_t * mp)
   session = vcl_session_get (wrk, sid);
   if (mp->retval)
     {
-      VDBG (0, "VCL<%d>: ERROR: vpp handle 0x%llx, sid %u: bind failed: %U",
-	    getpid (), mp->handle, sid, format_api_error, ntohl (mp->retval));
+      VERR ("session %u [0x%llx]: bind failed: %U", sid, mp->handle,
+	    format_api_error, mp->retval);
       if (session)
 	{
 	  session->session_state = STATE_FAILED;
@@ -442,21 +482,24 @@ vcl_session_bound_handler (vcl_worker_t * wrk, session_bound_msg_t * mp)
 	}
       else
 	{
-	  clib_warning ("[%s] ERROR: vpp handle 0x%llx, sid %u: "
-			"Invalid session index (%u)!",
-			getpid (), mp->handle, sid);
+	  VDBG (0, "ERROR: session %u [0x%llx]: Invalid session index!",
+		sid, mp->handle);
 	  return VCL_INVALID_SESSION_INDEX;
 	}
     }
 
   session->vpp_handle = mp->handle;
   session->transport.is_ip4 = mp->lcl_is_ip4;
-  clib_memcpy (&session->transport.lcl_ip, mp->lcl_ip,
-	       sizeof (ip46_address_t));
+  clib_memcpy_fast (&session->transport.lcl_ip, mp->lcl_ip,
+		    sizeof (ip46_address_t));
   session->transport.lcl_port = mp->lcl_port;
   vcl_session_table_add_listener (wrk, mp->handle, sid);
   session->session_state = STATE_LISTEN;
 
+  session->vpp_evt_q = uword_to_pointer (mp->vpp_evt_q, svm_msg_q_t *);
+  vec_validate (wrk->vpp_event_queues, 0);
+  wrk->vpp_event_queues[0] = session->vpp_evt_q;
+
   if (session->is_dgram)
     {
       svm_fifo_t *rx_fifo, *tx_fifo;
@@ -469,41 +512,153 @@ vcl_session_bound_handler (vcl_worker_t * wrk, session_bound_msg_t * mp)
       session->tx_fifo = tx_fifo;
     }
 
-  VDBG (1, "VCL<%d>: vpp handle 0x%llx, sid %u: bind succeeded!",
-	getpid (), mp->handle, sid);
+  VDBG (0, "session %u [0x%llx]: listen succeeded!", sid, mp->handle);
   return sid;
 }
 
-int
-vcl_handle_mq_ctrl_event (vcl_worker_t * wrk, session_event_t * e)
+static void
+vcl_session_unlisten_reply_handler (vcl_worker_t * wrk, void *data)
+{
+  session_unlisten_reply_msg_t *mp = (session_unlisten_reply_msg_t *) data;
+  vcl_session_t *s;
+
+  s = vcl_session_get_w_vpp_handle (wrk, mp->handle);
+  if (!s || s->session_state != STATE_DISCONNECT)
+    {
+      VDBG (0, "Unlisten reply with wrong handle %llx", mp->handle);
+      return;
+    }
+
+  if (mp->retval)
+    VDBG (0, "ERROR: session %u [0xllx]: unlisten failed: %U",
+	  s->session_index, mp->handle, format_api_error, ntohl (mp->retval));
+
+  if (mp->context != wrk->wrk_index)
+    VDBG (0, "wrong context");
+
+  vcl_session_table_del_vpp_handle (wrk, mp->handle);
+  vcl_session_free (wrk, s);
+}
+
+static vcl_session_t *
+vcl_session_accepted (vcl_worker_t * wrk, session_accepted_msg_t * msg)
 {
-  session_accepted_msg_t *accepted_msg;
-  session_disconnected_msg_t *disconnected_msg;
   vcl_session_msg_t *vcl_msg;
   vcl_session_t *session;
-  u64 handle;
-  u32 sid;
+
+  session = vcl_session_get_w_vpp_handle (wrk, msg->handle);
+  if (PREDICT_FALSE (session != 0))
+    VWRN ("session overlap handle %lu state %u!", msg->handle,
+	  session->session_state);
+
+  session = vcl_session_table_lookup_listener (wrk, msg->listener_handle);
+  if (!session)
+    {
+      VERR ("couldn't find listen session: listener handle %llx",
+	    msg->listener_handle);
+      return 0;
+    }
+
+  clib_fifo_add2 (session->accept_evts_fifo, vcl_msg);
+  vcl_msg->accepted_msg = *msg;
+  /* Session handle points to listener until fully accepted by app */
+  vcl_session_table_add_vpp_handle (wrk, msg->handle, session->session_index);
+
+  return session;
+}
+
+static vcl_session_t *
+vcl_session_disconnected_handler (vcl_worker_t * wrk,
+				  session_disconnected_msg_t * msg)
+{
+  vcl_session_t *session;
+
+  session = vcl_session_get_w_vpp_handle (wrk, msg->handle);
+  if (!session)
+    {
+      VDBG (0, "request to disconnect unknown handle 0x%llx", msg->handle);
+      return 0;
+    }
+
+  /* Caught a disconnect before actually accepting the session */
+  if (session->session_state == STATE_LISTEN)
+    {
+      if (!vcl_flag_accepted_session (session, msg->handle,
+				      VCL_ACCEPTED_F_CLOSED))
+	VDBG (0, "session was not accepted!");
+      return 0;
+    }
+
+  session->session_state = STATE_VPP_CLOSING;
+  return session;
+}
+
+static void
+vcl_session_req_worker_update_handler (vcl_worker_t * wrk, void *data)
+{
+  session_req_worker_update_msg_t *msg;
+  vcl_session_t *s;
+
+  msg = (session_req_worker_update_msg_t *) data;
+  s = vcl_session_get_w_vpp_handle (wrk, msg->session_handle);
+  if (!s)
+    return;
+
+  vec_add1 (wrk->pending_session_wrk_updates, s->session_index);
+}
+
+static void
+vcl_session_worker_update_reply_handler (vcl_worker_t * wrk, void *data)
+{
+  session_worker_update_reply_msg_t *msg;
+  vcl_session_t *s;
+
+  msg = (session_worker_update_reply_msg_t *) data;
+  s = vcl_session_get_w_vpp_handle (wrk, msg->handle);
+  if (!s)
+    {
+      VDBG (0, "unknown handle 0x%llx", msg->handle);
+      return;
+    }
+  if (vcl_wait_for_segment (msg->segment_handle))
+    {
+      clib_warning ("segment for session %u couldn't be mounted!",
+		    s->session_index);
+      return;
+    }
+
+  if (s->rx_fifo)
+    {
+      s->rx_fifo = uword_to_pointer (msg->rx_fifo, svm_fifo_t *);
+      s->tx_fifo = uword_to_pointer (msg->tx_fifo, svm_fifo_t *);
+      s->rx_fifo->client_session_index = s->session_index;
+      s->tx_fifo->client_session_index = s->session_index;
+      s->rx_fifo->client_thread_index = wrk->wrk_index;
+      s->tx_fifo->client_thread_index = wrk->wrk_index;
+    }
+  s->session_state = STATE_UPDATED;
+
+  VDBG (0, "session %u[0x%llx] moved to worker %u", s->session_index,
+	s->vpp_handle, wrk->wrk_index);
+}
+
+static int
+vcl_handle_mq_event (vcl_worker_t * wrk, session_event_t * e)
+{
+  session_disconnected_msg_t *disconnected_msg;
+  vcl_session_t *session;
 
   switch (e->event_type)
     {
-    case FIFO_EVENT_APP_RX:
-      clib_warning ("unhandled rx: sid %u (0x%x)",
-		    e->fifo->client_session_index,
-		    e->fifo->client_session_index);
+    case SESSION_IO_EVT_RX:
+    case SESSION_IO_EVT_TX:
+      session = vcl_session_get (wrk, e->session_index);
+      if (!session || !(session->session_state & STATE_OPEN))
+	break;
+      vec_add1 (wrk->unhandled_evts_vector, *e);
       break;
     case SESSION_CTRL_EVT_ACCEPTED:
-      accepted_msg = (session_accepted_msg_t *) e->data;
-      handle = accepted_msg->listener_handle;
-      session = vcl_session_table_lookup_listener (wrk, handle);
-      if (!session)
-	{
-	  clib_warning ("VCL<%d>: ERROR: couldn't find listen session:"
-			"listener handle %llx", getpid (), handle);
-	  break;
-	}
-
-      clib_fifo_add2 (session->accept_evts_fifo, vcl_msg);
-      vcl_msg->accepted_msg = *accepted_msg;
+      vcl_session_accepted (wrk, (session_accepted_msg_t *) e->data);
       break;
     case SESSION_CTRL_EVT_CONNECTED:
       vcl_session_connected_handler (wrk,
@@ -511,17 +666,11 @@ vcl_handle_mq_ctrl_event (vcl_worker_t * wrk, session_event_t * e)
       break;
     case SESSION_CTRL_EVT_DISCONNECTED:
       disconnected_msg = (session_disconnected_msg_t *) e->data;
-      sid = vcl_session_index_from_vpp_handle (wrk, disconnected_msg->handle);
-      session = vcl_session_get (wrk, sid);
+      session = vcl_session_disconnected_handler (wrk, disconnected_msg);
       if (!session)
-	{
-	  VDBG (0, "request to disconnect unknown handle 0x%llx",
-		disconnected_msg->handle);
-	  break;
-	}
-      session->session_state = STATE_DISCONNECT;
-      VDBG (0, "disconnected handle 0xllx, sid %u", disconnected_msg->handle,
-	    sid);
+	break;
+      VDBG (0, "disconnected session %u [0x%llx]", session->session_index,
+	    session->vpp_handle);
       break;
     case SESSION_CTRL_EVT_RESET:
       vcl_session_reset_handler (wrk, (session_reset_msg_t *) e->data);
@@ -529,15 +678,24 @@ vcl_handle_mq_ctrl_event (vcl_worker_t * wrk, session_event_t * e)
     case SESSION_CTRL_EVT_BOUND:
       vcl_session_bound_handler (wrk, (session_bound_msg_t *) e->data);
       break;
+    case SESSION_CTRL_EVT_UNLISTEN_REPLY:
+      vcl_session_unlisten_reply_handler (wrk, e->data);
+      break;
+    case SESSION_CTRL_EVT_REQ_WORKER_UPDATE:
+      vcl_session_req_worker_update_handler (wrk, e->data);
+      break;
+    case SESSION_CTRL_EVT_WORKER_UPDATE_REPLY:
+      vcl_session_worker_update_reply_handler (wrk, e->data);
+      break;
     default:
       clib_warning ("unhandled %u", e->event_type);
     }
   return VPPCOM_OK;
 }
 
-static inline int
+static int
 vppcom_wait_for_session_state_change (u32 session_index,
-				      session_state_t state,
+				      vcl_session_state_t state,
 				      f64 wait_for_time)
 {
   vcl_worker_t *wrk = vcl_worker_get_current ();
@@ -563,20 +721,69 @@ vppcom_wait_for_session_state_change (u32 session_index,
 	}
 
       if (svm_msg_q_sub (wrk->app_event_queue, &msg, SVM_Q_NOWAIT, 0))
-	continue;
+	{
+	  usleep (100);
+	  continue;
+	}
       e = svm_msg_q_msg_data (wrk->app_event_queue, &msg);
-      vcl_handle_mq_ctrl_event (wrk, e);
+      vcl_handle_mq_event (wrk, e);
       svm_msg_q_free_msg (wrk->app_event_queue, &msg);
     }
   while (clib_time_now (&wrk->clib_time) < timeout);
 
-  VDBG (0, "VCL<%d>: timeout waiting for state 0x%x (%s)", getpid (), state,
+  VDBG (0, "timeout waiting for state 0x%x (%s)", state,
 	vppcom_session_state_str (state));
   vcl_evt (VCL_EVT_SESSION_TIMEOUT, session, session_state);
 
   return VPPCOM_ETIMEDOUT;
 }
 
+static void
+vcl_handle_pending_wrk_updates (vcl_worker_t * wrk)
+{
+  vcl_session_state_t state;
+  vcl_session_t *s;
+  u32 *sip;
+
+  if (PREDICT_TRUE (vec_len (wrk->pending_session_wrk_updates) == 0))
+    return;
+
+  vec_foreach (sip, wrk->pending_session_wrk_updates)
+  {
+    s = vcl_session_get (wrk, *sip);
+    vcl_send_session_worker_update (wrk, s, wrk->wrk_index);
+    state = s->session_state;
+    vppcom_wait_for_session_state_change (s->session_index, STATE_UPDATED, 5);
+    s->session_state = state;
+  }
+  vec_reset_length (wrk->pending_session_wrk_updates);
+}
+
+void
+vcl_flush_mq_events (void)
+{
+  vcl_worker_t *wrk = vcl_worker_get_current ();
+  svm_msg_q_msg_t *msg;
+  session_event_t *e;
+  svm_msg_q_t *mq;
+  int i;
+
+  mq = wrk->app_event_queue;
+  svm_msg_q_lock (mq);
+  vcl_mq_dequeue_batch (wrk, mq, ~0);
+  svm_msg_q_unlock (mq);
+
+  for (i = 0; i < vec_len (wrk->mq_msg_vector); i++)
+    {
+      msg = vec_elt_at_index (wrk->mq_msg_vector, i);
+      e = svm_msg_q_msg_data (mq, msg);
+      vcl_handle_mq_event (wrk, e);
+      svm_msg_q_free_msg (mq, msg);
+    }
+  vec_reset_length (wrk->mq_msg_vector);
+  vcl_handle_pending_wrk_updates (wrk);
+}
+
 static int
 vppcom_app_session_enable (void)
 {
@@ -588,8 +795,8 @@ vppcom_app_session_enable (void)
       rv = vcl_wait_for_app_state_change (STATE_APP_ENABLED);
       if (PREDICT_FALSE (rv))
 	{
-	  VDBG (0, "VCL<%d>: application session enable timed out! "
-		"returning %d (%s)", getpid (), rv, vppcom_retval_str (rv));
+	  VDBG (0, "application session enable timed out! returning %d (%s)",
+		rv, vppcom_retval_str (rv));
 	  return rv;
 	}
     }
@@ -605,8 +812,8 @@ vppcom_app_attach (void)
   rv = vcl_wait_for_app_state_change (STATE_APP_ATTACHED);
   if (PREDICT_FALSE (rv))
     {
-      VDBG (0, "VCL<%d>: application attach timed out! returning %d (%s)",
-	    getpid (), rv, vppcom_retval_str (rv));
+      VDBG (0, "application attach timed out! returning %d (%s)", rv,
+	    vppcom_retval_str (rv));
       return rv;
     }
 
@@ -617,23 +824,35 @@ static int
 vppcom_session_unbind (u32 session_handle)
 {
   vcl_worker_t *wrk = vcl_worker_get_current ();
+  session_accepted_msg_t *accepted_msg;
   vcl_session_t *session = 0;
+  vcl_session_msg_t *evt;
   u64 vpp_handle;
 
   session = vcl_session_get_w_handle (wrk, session_handle);
   if (!session)
     return VPPCOM_EBADFD;
 
+  /* Flush pending accept events, if any */
+  while (clib_fifo_elts (session->accept_evts_fifo))
+    {
+      clib_fifo_sub2 (session->accept_evts_fifo, evt);
+      accepted_msg = &evt->accepted_msg;
+      vcl_session_table_del_vpp_handle (wrk, accepted_msg->handle);
+      vcl_send_session_accepted_reply (session->vpp_evt_q,
+				       accepted_msg->context,
+				       session->vpp_handle, -1);
+    }
+  clib_fifo_free (session->accept_evts_fifo);
+
   vpp_handle = session->vpp_handle;
-  vcl_session_table_del_listener (wrk, vpp_handle);
   session->vpp_handle = ~0;
   session->session_state = STATE_DISCONNECT;
 
-  VDBG (1, "VCL<%d>: vpp handle 0x%llx, sid %u: sending unbind msg! new state"
-	" 0x%x (%s)", getpid (), vpp_handle, session_handle, STATE_DISCONNECT,
-	vppcom_session_state_str (STATE_DISCONNECT));
+  VDBG (1, "session %u [0x%llx]: sending unbind!", session->session_index,
+	vpp_handle);
   vcl_evt (VCL_EVT_UNBIND, session);
-  vppcom_send_unbind_sock (vpp_handle);
+  vppcom_send_unbind_sock (wrk, vpp_handle);
 
   return VPPCOM_OK;
 }
@@ -643,43 +862,71 @@ vppcom_session_disconnect (u32 session_handle)
 {
   vcl_worker_t *wrk = vcl_worker_get_current ();
   svm_msg_q_t *vpp_evt_q;
-  vcl_session_t *session;
-  session_state_t state;
+  vcl_session_t *session, *listen_session;
+  vcl_session_state_t state;
   u64 vpp_handle;
 
   session = vcl_session_get_w_handle (wrk, session_handle);
+  if (!session)
+    return VPPCOM_EBADFD;
+
   vpp_handle = session->vpp_handle;
   state = session->session_state;
 
-  VDBG (1, "VCL<%d>: vpp handle 0x%llx, sid %u state 0x%x (%s)", getpid (),
-	vpp_handle, session_handle, state, vppcom_session_state_str (state));
+  VDBG (1, "session %u [0x%llx] state 0x%x (%s)", session->session_index,
+	vpp_handle, state, vppcom_session_state_str (state));
 
   if (PREDICT_FALSE (state & STATE_LISTEN))
     {
-      clib_warning ("VCL<%d>: ERROR: vpp handle 0x%llx, sid %u: "
-		    "Cannot disconnect a listen socket!",
-		    getpid (), vpp_handle, session_handle);
+      VDBG (0, "ERROR: Cannot disconnect a listen socket!");
       return VPPCOM_EBADFD;
     }
 
-  if (state & STATE_CLOSE_ON_EMPTY)
+  if (state & STATE_VPP_CLOSING)
     {
       vpp_evt_q = vcl_session_vpp_evt_q (wrk, session);
-      vcl_send_session_disconnected_reply (vpp_evt_q, vcm->my_client_index,
+      vcl_send_session_disconnected_reply (vpp_evt_q, wrk->my_client_index,
 					   vpp_handle, 0);
-      VDBG (1, "VCL<%d>: vpp handle 0x%llx, sid %u: sending disconnect "
-	    "REPLY...", getpid (), vpp_handle, session_handle);
+      VDBG (1, "session %u [0x%llx]: sending disconnect REPLY...",
+	    session->session_index, vpp_handle);
     }
   else
     {
-      VDBG (1, "VCL<%d>: vpp handle 0x%llx, sid %u: sending disconnect...",
-	    getpid (), vpp_handle, session_handle);
+      VDBG (1, "session %u [0x%llx]: sending disconnect...",
+	    session->session_index, vpp_handle);
       vppcom_send_disconnect_session (vpp_handle);
     }
 
+  if (session->listener_index != VCL_INVALID_SESSION_INDEX)
+    {
+      listen_session = vcl_session_get (wrk, session->listener_index);
+      listen_session->n_accepted_sessions--;
+    }
+
   return VPPCOM_OK;
 }
 
+/**
+ * Handle app exit
+ *
+ * Notify vpp of the disconnect and mark the worker as free. If we're the
+ * last worker, do a full cleanup otherwise, since we're probably a forked
+ * child, avoid syscalls as much as possible. We might've lost privileges.
+ */
+void
+vppcom_app_exit (void)
+{
+  if (!pool_elts (vcm->workers))
+    return;
+  vcl_worker_cleanup (vcl_worker_get_current (), 1 /* notify vpp */ );
+  vcl_set_worker_index (~0);
+  vcl_elog_stop (vcm);
+  if (vec_len (vcm->workers) == 1)
+    vl_client_disconnect_from_vlib ();
+  else
+    vl_client_send_disconnect (1 /* vpp should cleanup */ );
+}
+
 /*
  * VPPCOM Public API functions
  */
@@ -689,56 +936,59 @@ vppcom_app_create (char *app_name)
   vppcom_cfg_t *vcl_cfg = &vcm->cfg;
   int rv;
 
-  if (!vcm->is_init)
+  if (vcm->is_init)
     {
-      vcm->is_init = 1;
-      vppcom_cfg (&vcm->cfg);
-      vcl_cfg = &vcm->cfg;
-
-      vcm->main_cpu = pthread_self ();
-      vppcom_init_error_string_table ();
-      svm_fifo_segment_main_init (vcl_cfg->segment_baseva,
-				  20 /* timeout in secs */ );
-      pool_init_fixed (vcm->workers, vcl_cfg->max_workers);
-      vcl_worker_alloc_and_init ();
+      VDBG (1, "already initialized");
+      return VPPCOM_EEXIST;
     }
 
-  if (vcm->my_client_index == ~0)
-    {
-      /* API hookup and connect to VPP */
-      vppcom_api_hookup ();
-      vcl_elog_init (vcm);
-      vcm->app_state = STATE_APP_START;
-      rv = vppcom_connect_to_vpp (app_name);
-      if (rv)
-	{
-	  clib_warning ("VCL<%d>: ERROR: couldn't connect to VPP!",
-			getpid ());
-	  return rv;
-	}
+  vcm->is_init = 1;
+  vppcom_cfg (&vcm->cfg);
+  vcl_cfg = &vcm->cfg;
 
-      VDBG (0, "VCL<%d>: sending session enable", getpid ());
-      rv = vppcom_app_session_enable ();
-      if (rv)
-	{
-	  clib_warning ("VCL<%d>: ERROR: vppcom_app_session_enable() "
-			"failed!", getpid ());
-	  return rv;
-	}
+  vcm->main_cpu = pthread_self ();
+  vcm->main_pid = getpid ();
+  vcm->app_name = format (0, "%s", app_name);
+  vppcom_init_error_string_table ();
+  fifo_segment_main_init (&vcm->segment_main, vcl_cfg->segment_baseva,
+			  20 /* timeout in secs */ );
+  pool_alloc (vcm->workers, vcl_cfg->max_workers);
+  clib_spinlock_init (&vcm->workers_lock);
+  clib_rwlock_init (&vcm->segment_table_lock);
+  atexit (vppcom_app_exit);
 
-      VDBG (0, "VCL<%d>: sending app attach", getpid ());
-      rv = vppcom_app_attach ();
-      if (rv)
-	{
-	  clib_warning ("VCL<%d>: ERROR: vppcom_app_attach() failed!",
-			getpid ());
-	  return rv;
-	}
+  /* Allocate default worker */
+  vcl_worker_alloc_and_init ();
+
+  /* API hookup and connect to VPP */
+  vppcom_api_hookup ();
+  vcl_elog_init (vcm);
+  vcm->app_state = STATE_APP_START;
+  rv = vppcom_connect_to_vpp (app_name);
+  if (rv)
+    {
+      VERR ("couldn't connect to VPP!");
+      return rv;
+    }
+  VDBG (0, "sending session enable");
+  rv = vppcom_app_session_enable ();
+  if (rv)
+    {
+      VERR ("vppcom_app_session_enable() failed!");
+      return rv;
+    }
 
-      VDBG (0, "VCL<%d>: app_name '%s', my_client_index %d (0x%x)",
-	    getpid (), app_name, vcm->my_client_index, vcm->my_client_index);
+  VDBG (0, "sending app attach");
+  rv = vppcom_app_attach ();
+  if (rv)
+    {
+      VERR ("vppcom_app_attach() failed!");
+      return rv;
     }
 
+  VDBG (0, "app_name '%s', my_client_index %d (0x%x)", app_name,
+	vcm->workers[0].my_client_index, vcm->workers[0].my_client_index);
+
   return VPPCOM_OK;
 }
 
@@ -748,26 +998,32 @@ vppcom_app_destroy (void)
   int rv;
   f64 orig_app_timeout;
 
-  if (vcm->my_client_index == ~0)
+  if (!pool_elts (vcm->workers))
     return;
 
-  VDBG (0, "VCL<%d>: detaching from VPP, my_client_index %d (0x%x)",
-	getpid (), vcm->my_client_index, vcm->my_client_index);
   vcl_evt (VCL_EVT_DETACH, vcm);
 
-  vppcom_app_send_detach ();
-  orig_app_timeout = vcm->cfg.app_timeout;
-  vcm->cfg.app_timeout = 2.0;
-  rv = vcl_wait_for_app_state_change (STATE_APP_ENABLED);
-  vcm->cfg.app_timeout = orig_app_timeout;
-  if (PREDICT_FALSE (rv))
-    VDBG (0, "VCL<%d>: application detach timed out! returning %d (%s)",
-	  getpid (), rv, vppcom_retval_str (rv));
+  if (pool_elts (vcm->workers) == 1)
+    {
+      vppcom_app_send_detach ();
+      orig_app_timeout = vcm->cfg.app_timeout;
+      vcm->cfg.app_timeout = 2.0;
+      rv = vcl_wait_for_app_state_change (STATE_APP_ENABLED);
+      vcm->cfg.app_timeout = orig_app_timeout;
+      if (PREDICT_FALSE (rv))
+	VDBG (0, "application detach timed out! returning %d (%s)", rv,
+	      vppcom_retval_str (rv));
+      vec_free (vcm->app_name);
+      vcl_worker_cleanup (vcl_worker_get_current (), 0 /* notify vpp */ );
+    }
+  else
+    {
+      vcl_worker_cleanup (vcl_worker_get_current (), 1 /* notify vpp */ );
+    }
 
+  vcl_set_worker_index (~0);
   vcl_elog_stop (vcm);
   vl_client_disconnect_from_vlib ();
-  vcm->my_client_index = ~0;
-  vcm->app_state = STATE_APP_START;
 }
 
 int
@@ -781,7 +1037,7 @@ vppcom_session_create (u8 proto, u8 is_nonblocking)
   session->session_type = proto;
   session->session_state = STATE_START;
   session->vpp_handle = ~0;
-  session->is_dgram = proto == VPPCOM_PROTO_UDP;
+  session->is_dgram = vcl_proto_is_dgram (proto);
 
   if (is_nonblocking)
     VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_NONBLOCK);
@@ -789,129 +1045,109 @@ vppcom_session_create (u8 proto, u8 is_nonblocking)
   vcl_evt (VCL_EVT_CREATE, session, session_type, session->session_state,
 	   is_nonblocking, session_index);
 
-  VDBG (0, "VCL<%d>: sid %u", getpid (), session->session_index);
+  VDBG (0, "created session %u", session->session_index);
 
   return vcl_session_handle (session);
 }
 
 int
-vppcom_session_close (uint32_t session_handle)
+vcl_session_cleanup (vcl_worker_t * wrk, vcl_session_t * session,
+		     vcl_session_handle_t sh, u8 do_disconnect)
 {
-  vcl_worker_t *wrk = vcl_worker_get_current ();
-  vcl_session_t *session = 0;
-  u8 is_vep, is_vep_session;
-  session_state_t state;
+  vcl_session_state_t state;
   u32 next_sh, vep_sh;
   int rv = VPPCOM_OK;
   u64 vpp_handle;
-
-  session = vcl_session_get_w_handle (wrk, session_handle);
-  if (!session)
-    return VPPCOM_EBADFD;
+  u8 is_vep;
 
   is_vep = session->is_vep;
-  is_vep_session = session->is_vep_session;
   next_sh = session->vep.next_sh;
   vep_sh = session->vep.vep_sh;
   state = session->session_state;
   vpp_handle = session->vpp_handle;
 
-  if (VPPCOM_DEBUG > 0)
-    {
-      if (is_vep)
-	clib_warning ("VCL<%d>: vep_idx %u / sid %u: "
-		      "closing epoll session...",
-		      getpid (), session_handle, session_handle);
-      else
-	clib_warning ("VCL<%d>: vpp handle 0x%llx, sid %d: "
-		      "closing session...",
-		      getpid (), vpp_handle, session_handle);
-    }
+  VDBG (1, "session %u [0x%llx] closing", session->session_index, vpp_handle);
 
   if (is_vep)
     {
       while (next_sh != ~0)
 	{
-	  rv = vppcom_epoll_ctl (session_handle, EPOLL_CTL_DEL, next_sh, 0);
+	  rv = vppcom_epoll_ctl (sh, EPOLL_CTL_DEL, next_sh, 0);
 	  if (PREDICT_FALSE (rv < 0))
-	    VDBG (0, "VCL<%d>: vpp handle 0x%llx, sid %u: EPOLL_CTL_DEL "
-		  "vep_idx %u failed! rv %d (%s)",
-		  getpid (), vpp_handle, next_sh, vep_sh,
-		  rv, vppcom_retval_str (rv));
+	    VDBG (0, "vpp handle 0x%llx, sh %u: EPOLL_CTL_DEL vep_idx %u"
+		  " failed! rv %d (%s)", vpp_handle, next_sh, vep_sh, rv,
+		  vppcom_retval_str (rv));
 
 	  next_sh = session->vep.next_sh;
 	}
     }
   else
     {
-      if (is_vep_session)
+      if (session->is_vep_session)
 	{
-	  rv = vppcom_epoll_ctl (vep_sh, EPOLL_CTL_DEL, session_handle, 0);
+	  rv = vppcom_epoll_ctl (vep_sh, EPOLL_CTL_DEL, sh, 0);
 	  if (rv < 0)
-	    VDBG (0, "VCL<%d>: vpp handle 0x%llx, sid %u: EPOLL_CTL_DEL "
-		  "vep_idx %u failed! rv %d (%s)",
-		  getpid (), vpp_handle, session_handle,
+	    VDBG (0, "session %u [0x%llx]: EPOLL_CTL_DEL vep_idx %u "
+		  "failed! rv %d (%s)", session->session_index, vpp_handle,
 		  vep_sh, rv, vppcom_retval_str (rv));
 	}
 
+      if (!do_disconnect)
+	{
+	  VDBG (1, "session %u [0x%llx] disconnect skipped",
+		session->session_index, vpp_handle);
+	  goto cleanup;
+	}
+
       if (state & STATE_LISTEN)
 	{
-	  rv = vppcom_session_unbind (session_handle);
+	  rv = vppcom_session_unbind (sh);
 	  if (PREDICT_FALSE (rv < 0))
-	    VDBG (0, "VCL<%d>: vpp handle 0x%llx, sid %u: listener unbind "
-		  "failed! rv %d (%s)",
-		  getpid (), vpp_handle, session_handle,
-		  rv, vppcom_retval_str (rv));
+	    VDBG (0, "session %u [0x%llx]: listener unbind failed! "
+		  "rv %d (%s)", session->session_index, vpp_handle, rv,
+		  vppcom_retval_str (rv));
+	  return rv;
 	}
-      else if (state & STATE_OPEN)
+      else if ((state & STATE_OPEN)
+	       || (vcl_session_is_connectable_listener (wrk, session)))
 	{
-	  rv = vppcom_session_disconnect (session_handle);
+	  rv = vppcom_session_disconnect (sh);
 	  if (PREDICT_FALSE (rv < 0))
-	    clib_warning ("VCL<%d>: ERROR: vpp handle 0x%llx, sid %u: "
-			  "session disconnect failed! rv %d (%s)",
-			  getpid (), vpp_handle, session_handle,
-			  rv, vppcom_retval_str (rv));
+	    VDBG (0, "ERROR: session %u [0x%llx]: disconnect failed!"
+		  " rv %d (%s)", session->session_index, vpp_handle,
+		  rv, vppcom_retval_str (rv));
+	}
+      else if (state == STATE_DISCONNECT)
+	{
+	  svm_msg_q_t *mq = vcl_session_vpp_evt_q (wrk, session);
+	  vcl_send_session_reset_reply (mq, wrk->my_client_index,
+					session->vpp_handle, 0);
 	}
     }
 
-  if (vcl_session_is_ct (session))
-    {
-      vcl_cut_through_registration_t *ctr;
-      uword mq_addr;
-
-      mq_addr = pointer_to_uword (session->our_evt_q);
-      ctr = vcl_ct_registration_lock_and_lookup (wrk, mq_addr);
-      ASSERT (ctr);
-      if (ctr->epoll_evt_conn_index != ~0)
-	vcl_mq_epoll_del_evfd (wrk, ctr->epoll_evt_conn_index);
-      VDBG (0, "Removing ct registration %u",
-	    vcl_ct_registration_index (wrk, ctr));
-      vcl_ct_registration_del (wrk, ctr);
-      vcl_ct_registration_lookup_del (wrk, mq_addr);
-      vcl_ct_registration_unlock (wrk);
-    }
+  VDBG (0, "session %u [0x%llx] removed", session->session_index, vpp_handle);
 
-  if (vpp_handle != ~0)
-    {
-      vcl_session_table_del_vpp_handle (wrk, vpp_handle);
-    }
+cleanup:
+  vcl_session_table_del_vpp_handle (wrk, vpp_handle);
   vcl_session_free (wrk, session);
-
-  if (VPPCOM_DEBUG > 0)
-    {
-      if (is_vep)
-	clib_warning ("VCL<%d>: vep_idx %u / sid %u: epoll session removed.",
-		      getpid (), session_handle, session_handle);
-      else
-	clib_warning ("VCL<%d>: vpp handle 0x%llx, sid %u: session removed.",
-		      getpid (), vpp_handle, session_handle);
-    }
-
   vcl_evt (VCL_EVT_CLOSE, session, rv);
 
   return rv;
 }
 
+int
+vppcom_session_close (uint32_t session_handle)
+{
+  vcl_worker_t *wrk = vcl_worker_get_current ();
+  vcl_session_t *session;
+
+  session = vcl_session_get_w_handle (wrk, session_handle);
+  if (!session)
+    return VPPCOM_EBADFD;
+  return vcl_session_cleanup (wrk, session, session_handle,
+			      1 /* do_disconnect */ );
+}
+
 int
 vppcom_session_bind (uint32_t session_handle, vppcom_endpt_t * ep)
 {
@@ -927,27 +1163,27 @@ vppcom_session_bind (uint32_t session_handle, vppcom_endpt_t * ep)
 
   if (session->is_vep)
     {
-      clib_warning ("VCL<%d>: ERROR: sid %u: cannot "
-		    "bind to an epoll session!", getpid (), session_handle);
+      VDBG (0, "ERROR: cannot bind to epoll session %u!",
+	    session->session_index);
       return VPPCOM_EBADFD;
     }
 
   session->transport.is_ip4 = ep->is_ip4;
   if (ep->is_ip4)
-    clib_memcpy (&session->transport.lcl_ip.ip4, ep->ip,
-		 sizeof (ip4_address_t));
+    clib_memcpy_fast (&session->transport.lcl_ip.ip4, ep->ip,
+		      sizeof (ip4_address_t));
   else
-    clib_memcpy (&session->transport.lcl_ip.ip6, ep->ip,
-		 sizeof (ip6_address_t));
+    clib_memcpy_fast (&session->transport.lcl_ip.ip6, ep->ip,
+		      sizeof (ip6_address_t));
   session->transport.lcl_port = ep->port;
 
-  VDBG (0, "VCL<%d>: sid %u: binding to local %s address %U port %u, "
-	"proto %s", getpid (), session_handle,
+  VDBG (0, "session %u handle %u: binding to local %s address %U port %u, "
+	"proto %s", session->session_index, session_handle,
 	session->transport.is_ip4 ? "IPv4" : "IPv6",
 	format_ip46_address, &session->transport.lcl_ip,
 	session->transport.is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
 	clib_net_to_host_u16 (session->transport.lcl_port),
-	session->session_type ? "UDP" : "TCP");
+	vppcom_proto_str (session->session_type));
   vcl_evt (VCL_EVT_BIND, session);
 
   if (session->session_type == VPPCOM_PROTO_UDP)
@@ -965,29 +1201,21 @@ vppcom_session_listen (uint32_t listen_sh, uint32_t q_len)
   int rv;
 
   listen_session = vcl_session_get_w_handle (wrk, listen_sh);
-  if (!listen_session)
+  if (!listen_session || listen_session->is_vep)
     return VPPCOM_EBADFD;
 
   if (q_len == 0 || q_len == ~0)
     q_len = vcm->cfg.listen_queue_size;
 
-  if (listen_session->is_vep)
-    {
-      clib_warning ("VCL<%d>: ERROR: sid %u: cannot listen on an "
-		    "epoll session!", getpid (), listen_sh);
-      return VPPCOM_EBADFD;
-    }
-
   listen_vpp_handle = listen_session->vpp_handle;
   if (listen_session->session_state & STATE_LISTEN)
     {
-      VDBG (0, "VCL<%d>: vpp handle 0x%llx, sid %u: already in listen state!",
-	    getpid (), listen_vpp_handle, listen_sh);
+      VDBG (0, "session %u [0x%llx]: already in listen state!",
+	    listen_sh, listen_vpp_handle);
       return VPPCOM_OK;
     }
 
-  VDBG (0, "VCL<%d>: vpp handle 0x%llx, sid %u: sending VPP bind+listen "
-	"request...", getpid (), listen_vpp_handle, listen_sh);
+  VDBG (0, "session %u: sending vpp listen request...", listen_sh);
 
   /*
    * Send listen request to vpp and wait for reply
@@ -1000,52 +1228,128 @@ vppcom_session_listen (uint32_t listen_sh, uint32_t q_len)
   if (PREDICT_FALSE (rv))
     {
       listen_session = vcl_session_get_w_handle (wrk, listen_sh);
-      VDBG (0, "VCL<%d>: vpp handle 0x%llx, sid %u: bind+listen failed! "
-	    "returning %d (%s)", getpid (), listen_session->vpp_handle,
-	    listen_sh, rv, vppcom_retval_str (rv));
+      VDBG (0, "session %u [0x%llx]: listen failed! returning %d (%s)",
+	    listen_sh, listen_session->vpp_handle, rv,
+	    vppcom_retval_str (rv));
       return rv;
     }
 
   return VPPCOM_OK;
 }
 
+int
+vppcom_session_tls_add_cert (uint32_t session_handle, char *cert,
+			     uint32_t cert_len)
+{
+
+  vcl_worker_t *wrk = vcl_worker_get_current ();
+  vcl_session_t *session = 0;
+
+  session = vcl_session_get_w_handle (wrk, session_handle);
+  if (!session)
+    return VPPCOM_EBADFD;
+
+  if (cert_len == 0 || cert_len == ~0)
+    return VPPCOM_EBADFD;
+
+  /*
+   * Send listen request to vpp and wait for reply
+   */
+  vppcom_send_application_tls_cert_add (session, cert, cert_len);
+
+  return VPPCOM_OK;
+
+}
+
+int
+vppcom_session_tls_add_key (uint32_t session_handle, char *key,
+			    uint32_t key_len)
+{
+
+  vcl_worker_t *wrk = vcl_worker_get_current ();
+  vcl_session_t *session = 0;
+
+  session = vcl_session_get_w_handle (wrk, session_handle);
+  if (!session)
+    return VPPCOM_EBADFD;
+
+  if (key_len == 0 || key_len == ~0)
+    return VPPCOM_EBADFD;
+
+  /*
+   * Send listen request to vpp and wait for reply
+   */
+  vppcom_send_application_tls_key_add (session, key, key_len);
+
+  return VPPCOM_OK;
+
+
+}
+
 static int
-validate_args_session_accept_ (vcl_worker_t * wrk,
-			       vcl_session_t * listen_session)
+validate_args_session_accept_ (vcl_worker_t * wrk, vcl_session_t * ls)
 {
-  /* Input validation - expects spinlock on sessions_lockp */
-  if (listen_session->is_vep)
+  if (ls->is_vep)
     {
-      clib_warning ("VCL<%d>: ERROR: sid %u: cannot accept on an "
-		    "epoll session!", getpid (),
-		    listen_session->session_index);
+      VDBG (0, "ERROR: cannot accept on epoll session %u!",
+	    ls->session_index);
       return VPPCOM_EBADFD;
     }
 
-  if (listen_session->session_state != STATE_LISTEN)
+  if ((ls->session_state != STATE_LISTEN)
+      && (!vcl_session_is_connectable_listener (wrk, ls)))
     {
-      clib_warning ("VCL<%d>: ERROR: vpp handle 0x%llx, sid %u: "
-		    "not in listen state! state 0x%x (%s)", getpid (),
-		    listen_session->vpp_handle, listen_session->session_index,
-		    listen_session->session_state,
-		    vppcom_session_state_str (listen_session->session_state));
+      VDBG (0,
+	    "ERROR: session [0x%llx]: not in listen state! state 0x%x"
+	    " (%s)", ls->vpp_handle, ls->session_state,
+	    vppcom_session_state_str (ls->session_state));
       return VPPCOM_EBADFD;
     }
   return VPPCOM_OK;
 }
 
+int
+vppcom_unformat_proto (uint8_t * proto, char *proto_str)
+{
+  if (!strcmp (proto_str, "TCP"))
+    *proto = VPPCOM_PROTO_TCP;
+  else if (!strcmp (proto_str, "tcp"))
+    *proto = VPPCOM_PROTO_TCP;
+  else if (!strcmp (proto_str, "UDP"))
+    *proto = VPPCOM_PROTO_UDP;
+  else if (!strcmp (proto_str, "udp"))
+    *proto = VPPCOM_PROTO_UDP;
+  else if (!strcmp (proto_str, "UDPC"))
+    *proto = VPPCOM_PROTO_UDPC;
+  else if (!strcmp (proto_str, "udpc"))
+    *proto = VPPCOM_PROTO_UDPC;
+  else if (!strcmp (proto_str, "SCTP"))
+    *proto = VPPCOM_PROTO_SCTP;
+  else if (!strcmp (proto_str, "sctp"))
+    *proto = VPPCOM_PROTO_SCTP;
+  else if (!strcmp (proto_str, "TLS"))
+    *proto = VPPCOM_PROTO_TLS;
+  else if (!strcmp (proto_str, "tls"))
+    *proto = VPPCOM_PROTO_TLS;
+  else if (!strcmp (proto_str, "QUIC"))
+    *proto = VPPCOM_PROTO_QUIC;
+  else if (!strcmp (proto_str, "quic"))
+    *proto = VPPCOM_PROTO_QUIC;
+  else
+    return 1;
+  return 0;
+}
+
 int
 vppcom_session_accept (uint32_t listen_session_handle, vppcom_endpt_t * ep,
 		       uint32_t flags)
 {
-  u32 client_session_index = ~0, listen_session_index;
+  u32 client_session_index = ~0, listen_session_index, accept_flags = 0;
   vcl_worker_t *wrk = vcl_worker_get_current ();
   session_accepted_msg_t accepted_msg;
   vcl_session_t *listen_session = 0;
   vcl_session_t *client_session = 0;
-  svm_msg_q_t *vpp_evt_q;
   vcl_session_msg_t *evt;
-  u64 listen_vpp_handle;
   svm_msg_q_msg_t msg;
   session_event_t *e;
   u8 is_nonblocking;
@@ -1062,6 +1366,7 @@ vppcom_session_accept (uint32_t listen_session_handle, vppcom_endpt_t * ep,
   if (clib_fifo_elts (listen_session->accept_evts_fifo))
     {
       clib_fifo_sub2 (listen_session->accept_evts_fifo, evt);
+      accept_flags = evt->flags;
       accepted_msg = evt->accepted_msg;
       goto handle;
     }
@@ -1079,69 +1384,68 @@ vppcom_session_accept (uint32_t listen_session_handle, vppcom_endpt_t * ep,
       e = svm_msg_q_msg_data (wrk->app_event_queue, &msg);
       if (e->event_type != SESSION_CTRL_EVT_ACCEPTED)
 	{
-	  clib_warning ("discarded event: %u", e->event_type);
+	  VDBG (0, "discarded event: %u", e->event_type);
 	  svm_msg_q_free_msg (wrk->app_event_queue, &msg);
 	  continue;
 	}
-      clib_memcpy (&accepted_msg, e->data, sizeof (accepted_msg));
+      clib_memcpy_fast (&accepted_msg, e->data, sizeof (accepted_msg));
       svm_msg_q_free_msg (wrk->app_event_queue, &msg);
       break;
     }
 
 handle:
 
-  client_session_index = vcl_session_accepted_handler (wrk, &accepted_msg);
+  client_session_index = vcl_session_accepted_handler (wrk, &accepted_msg,
+						       listen_session_index);
+  if (client_session_index == VCL_INVALID_SESSION_INDEX)
+    return VPPCOM_ECONNABORTED;
+
   listen_session = vcl_session_get (wrk, listen_session_index);
   client_session = vcl_session_get (wrk, client_session_index);
 
   if (flags & O_NONBLOCK)
     VCL_SESS_ATTR_SET (client_session->attr, VCL_SESS_ATTR_NONBLOCK);
 
-  listen_vpp_handle = listen_session->vpp_handle;
-  VDBG (0, "VCL<%d>: vpp handle 0x%llx, sid %u: Got a client request! "
-	"vpp handle 0x%llx, sid %u, flags %d, is_nonblocking %u",
-	getpid (), listen_vpp_handle, listen_session_handle,
-	client_session->vpp_handle, client_session_index,
-	flags, VCL_SESS_ATTR_TEST (client_session->attr,
-				   VCL_SESS_ATTR_NONBLOCK));
+  VDBG (1, "listener %u [0x%llx]: Got a connect request! session %u [0x%llx],"
+	" flags %d, is_nonblocking %u", listen_session->session_index,
+	listen_session->vpp_handle, client_session_index,
+	client_session->vpp_handle, flags,
+	VCL_SESS_ATTR_TEST (client_session->attr, VCL_SESS_ATTR_NONBLOCK));
 
   if (ep)
     {
       ep->is_ip4 = client_session->transport.is_ip4;
       ep->port = client_session->transport.rmt_port;
       if (client_session->transport.is_ip4)
-	clib_memcpy (ep->ip, &client_session->transport.rmt_ip.ip4,
-		     sizeof (ip4_address_t));
+	clib_memcpy_fast (ep->ip, &client_session->transport.rmt_ip.ip4,
+			  sizeof (ip4_address_t));
       else
-	clib_memcpy (ep->ip, &client_session->transport.rmt_ip.ip6,
-		     sizeof (ip6_address_t));
+	clib_memcpy_fast (ep->ip, &client_session->transport.rmt_ip.ip6,
+			  sizeof (ip6_address_t));
     }
 
-  if (accepted_msg.server_event_queue_address)
-    vpp_evt_q = uword_to_pointer (accepted_msg.vpp_event_queue_address,
-				  svm_msg_q_t *);
-  else
-    vpp_evt_q = client_session->vpp_evt_q;
-
-  vcl_send_session_accepted_reply (vpp_evt_q, client_session->client_context,
-				   client_session->vpp_handle, 0);
-
-  VDBG (0, "VCL<%d>: vpp handle 0x%llx, sid %u: accepted vpp handle 0x%llx, "
-	"sid %u connection from peer %s address %U port %u to local %s "
-	"address %U port %u", getpid (), listen_vpp_handle,
-	listen_session_handle, client_session->vpp_handle,
-	client_session_index,
-	client_session->transport.is_ip4 ? "IPv4" : "IPv6",
+  VDBG (0, "listener %u [0x%llx] accepted %u [0x%llx] peer: %U:%u "
+	"local: %U:%u", listen_session_handle, listen_session->vpp_handle,
+	client_session_index, client_session->vpp_handle,
 	format_ip46_address, &client_session->transport.rmt_ip,
 	client_session->transport.is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
 	clib_net_to_host_u16 (client_session->transport.rmt_port),
-	client_session->transport.is_ip4 ? "IPv4" : "IPv6",
 	format_ip46_address, &client_session->transport.lcl_ip,
 	client_session->transport.is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
 	clib_net_to_host_u16 (client_session->transport.lcl_port));
   vcl_evt (VCL_EVT_ACCEPT, client_session, listen_session,
 	   client_session_index);
 
+  /*
+   * Session might have been closed already
+   */
+  if (accept_flags)
+    {
+      if (accept_flags & VCL_ACCEPTED_F_CLOSED)
+	client_session->session_state = STATE_VPP_CLOSING;
+      else if (accept_flags & VCL_ACCEPTED_F_RESET)
+	client_session->session_state = STATE_DISCONNECT;
+    }
   return vcl_session_handle (client_session);
 }
 
@@ -1160,45 +1464,43 @@ vppcom_session_connect (uint32_t session_handle, vppcom_endpt_t * server_ep)
 
   if (PREDICT_FALSE (session->is_vep))
     {
-      clib_warning ("VCL<%d>: ERROR: sid %u: cannot "
-		    "connect on an epoll session!", getpid (),
-		    session_handle);
+      VDBG (0, "ERROR: cannot connect epoll session %u!",
+	    session->session_index);
       return VPPCOM_EBADFD;
     }
 
   if (PREDICT_FALSE (session->session_state & CLIENT_STATE_OPEN))
     {
-      VDBG (0, "VCL<%d>: vpp handle 0x%llx, sid %u: session already "
+      VDBG (0, "session handle %u [0x%llx]: session already "
 	    "connected to %s %U port %d proto %s, state 0x%x (%s)",
-	    getpid (), session->vpp_handle, session_handle,
-	    session->transport.is_ip4 ? "IPv4" : "IPv6",
-	    format_ip46_address,
+	    session_handle, session->vpp_handle,
+	    session->transport.is_ip4 ? "IPv4" : "IPv6", format_ip46_address,
 	    &session->transport.rmt_ip, session->transport.is_ip4 ?
 	    IP46_TYPE_IP4 : IP46_TYPE_IP6,
 	    clib_net_to_host_u16 (session->transport.rmt_port),
-	    session->session_type ? "UDP" : "TCP", session->session_state,
+	    vppcom_proto_str (session->session_type), session->session_state,
 	    vppcom_session_state_str (session->session_state));
       return VPPCOM_OK;
     }
 
   session->transport.is_ip4 = server_ep->is_ip4;
   if (session->transport.is_ip4)
-    clib_memcpy (&session->transport.rmt_ip.ip4, server_ep->ip,
-		 sizeof (ip4_address_t));
+    clib_memcpy_fast (&session->transport.rmt_ip.ip4, server_ep->ip,
+		      sizeof (ip4_address_t));
   else
-    clib_memcpy (&session->transport.rmt_ip.ip6, server_ep->ip,
-		 sizeof (ip6_address_t));
+    clib_memcpy_fast (&session->transport.rmt_ip.ip6, server_ep->ip,
+		      sizeof (ip6_address_t));
   session->transport.rmt_port = server_ep->port;
+  session->parent_handle = VCL_INVALID_SESSION_HANDLE;
 
-  VDBG (0, "VCL<%d>: vpp handle 0x%llx, sid %u: connecting to server %s %U "
-	"port %d proto %s",
-	getpid (), session->vpp_handle, session_handle,
+  VDBG (0, "session handle %u: connecting to server %s %U "
+	"port %d proto %s", session_handle,
 	session->transport.is_ip4 ? "IPv4" : "IPv6",
 	format_ip46_address,
 	&session->transport.rmt_ip, session->transport.is_ip4 ?
 	IP46_TYPE_IP4 : IP46_TYPE_IP6,
 	clib_net_to_host_u16 (session->transport.rmt_port),
-	session->session_type ? "UDP" : "TCP");
+	vppcom_proto_str (session->session_type));
 
   /*
    * Send connect request and wait for reply from vpp
@@ -1208,25 +1510,71 @@ vppcom_session_connect (uint32_t session_handle, vppcom_endpt_t * server_ep)
 					     vcm->cfg.session_timeout);
 
   session = vcl_session_get (wrk, session_index);
+  VDBG (0, "session %u [0x%llx]: connect %s!", session->session_index,
+	session->vpp_handle, rv ? "failed" : "succeeded");
 
-  if (PREDICT_FALSE (rv))
+  return rv;
+}
+
+int
+vppcom_session_stream_connect (uint32_t session_handle,
+			       uint32_t parent_session_handle)
+{
+  vcl_worker_t *wrk = vcl_worker_get_current ();
+  vcl_session_t *session, *parent_session;
+  u32 session_index, parent_session_index;
+  int rv;
+
+  session = vcl_session_get_w_handle (wrk, session_handle);
+  if (!session)
+    return VPPCOM_EBADFD;
+  parent_session = vcl_session_get_w_handle (wrk, parent_session_handle);
+  if (!parent_session)
+    return VPPCOM_EBADFD;
+
+  session_index = session->session_index;
+  parent_session_index = parent_session->session_index;
+  if (PREDICT_FALSE (session->is_vep))
     {
-      if (VPPCOM_DEBUG > 0)
-	{
-	  if (session)
-	    clib_warning ("VCL<%d>: vpp handle 0x%llx, sid %u: connect "
-			  "failed! returning %d (%s)", getpid (),
-			  session->vpp_handle, session_handle, rv,
-			  vppcom_retval_str (rv));
-	  else
-	    clib_warning ("VCL<%d>: no session for sid %u: connect failed! "
-			  "returning %d (%s)", getpid (),
-			  session_handle, rv, vppcom_retval_str (rv));
-	}
+      VDBG (0, "ERROR: cannot connect epoll session %u!",
+	    session->session_index);
+      return VPPCOM_EBADFD;
     }
-  else
-    VDBG (0, "VCL<%d>: vpp handle 0x%llx, sid %u: connected!",
-	  getpid (), session->vpp_handle, session_handle);
+
+  if (PREDICT_FALSE (session->session_state & CLIENT_STATE_OPEN))
+    {
+      VDBG (0, "session handle %u [0x%llx]: session already "
+	    "connected to session %u [0x%llx] proto %s, state 0x%x (%s)",
+	    session_handle, session->vpp_handle,
+	    parent_session_handle, parent_session->vpp_handle,
+	    vppcom_proto_str (session->session_type), session->session_state,
+	    vppcom_session_state_str (session->session_state));
+      return VPPCOM_OK;
+    }
+
+  /* Connect to quic session specifics */
+  session->transport.is_ip4 = parent_session->transport.is_ip4;
+  session->transport.rmt_ip.ip4.as_u32 = (uint32_t) 1;
+  session->transport.rmt_port = 0;
+  session->parent_handle = parent_session->vpp_handle;
+
+  VDBG (0, "session handle %u: connecting to session %u [0x%llx]",
+	session_handle, parent_session_handle, parent_session->vpp_handle);
+
+  /*
+   * Send connect request and wait for reply from vpp
+   */
+  vppcom_send_connect_sock (session);
+  rv = vppcom_wait_for_session_state_change (session_index, STATE_CONNECT,
+					     vcm->cfg.session_timeout);
+
+  session->listener_index = parent_session_index;
+  parent_session = vcl_session_get_w_handle (wrk, parent_session_handle);
+  parent_session->n_accepted_sessions++;
+
+  session = vcl_session_get (wrk, session_index);
+  VDBG (0, "session %u [0x%llx]: connect %s!", session->session_index,
+	session->vpp_handle, rv ? "failed" : "succeeded");
 
   return rv;
 }
@@ -1234,19 +1582,7 @@ vppcom_session_connect (uint32_t session_handle, vppcom_endpt_t * server_ep)
 static u8
 vcl_is_rx_evt_for_session (session_event_t * e, u32 sid, u8 is_ct)
 {
-  if (!is_ct)
-    return (e->event_type == FIFO_EVENT_APP_RX
-	    && e->fifo->client_session_index == sid);
-  else
-    return (e->event_type == SESSION_IO_EVT_CT_TX);
-}
-
-static inline u8
-vcl_session_is_readable (vcl_session_t * s)
-{
-  return ((s->session_state & STATE_OPEN)
-	  || (s->session_state == STATE_LISTEN
-	      && s->session_type == VPPCOM_PROTO_UDP));
+  return (e->event_type == SESSION_IO_EVT_RX && e->session_index == sid);
 }
 
 static inline int
@@ -1254,55 +1590,48 @@ vppcom_session_read_internal (uint32_t session_handle, void *buf, int n,
 			      u8 peek)
 {
   vcl_worker_t *wrk = vcl_worker_get_current ();
-  int n_read = 0, rv, is_nonblocking;
+  int n_read = 0, is_nonblocking;
   vcl_session_t *s = 0;
   svm_fifo_t *rx_fifo;
   svm_msg_q_msg_t msg;
   session_event_t *e;
   svm_msg_q_t *mq;
-  u8 is_full;
+  u8 is_ct;
 
   if (PREDICT_FALSE (!buf))
     return VPPCOM_EINVAL;
 
   s = vcl_session_get_w_handle (wrk, session_handle);
-  if (PREDICT_FALSE (!s))
+  if (PREDICT_FALSE (!s || s->is_vep))
     return VPPCOM_EBADFD;
 
-  if (PREDICT_FALSE (s->is_vep))
+  if (PREDICT_FALSE (!vcl_session_is_open (s)))
     {
-      clib_warning ("VCL<%d>: ERROR: sid %u: cannot "
-		    "read from an epoll session!", getpid (), session_handle);
-      return VPPCOM_EBADFD;
+      VDBG (0, "session %u[0x%llx] is not open! state 0x%x (%s)",
+	    s->session_index, s->vpp_handle, s->session_state,
+	    vppcom_session_state_str (s->session_state));
+      return vcl_session_closed_error (s);
     }
 
   is_nonblocking = VCL_SESS_ATTR_TEST (s->attr, VCL_SESS_ATTR_NONBLOCK);
-  rx_fifo = s->rx_fifo;
+  is_ct = vcl_session_is_ct (s);
+  mq = wrk->app_event_queue;
+  rx_fifo = is_ct ? s->ct_rx_fifo : s->rx_fifo;
+  s->has_rx_evt = 0;
 
-  if (PREDICT_FALSE (!vcl_session_is_readable (s)))
-    {
-      session_state_t state = s->session_state;
-      rv = ((state & STATE_DISCONNECT) ? VPPCOM_ECONNRESET : VPPCOM_ENOTCONN);
-
-      VDBG (0, "VCL<%d>: vpp handle 0x%llx, sid %u: %s session is not open! "
-	    "state 0x%x (%s), returning %d (%s)",
-	    getpid (), s->vpp_handle, session_handle, state,
-	    vppcom_session_state_str (state), rv, vppcom_retval_str (rv));
-      return rv;
-    }
-
-  mq = vcl_session_is_ct (s) ? s->our_evt_q : wrk->app_event_queue;
-  svm_fifo_unset_event (rx_fifo);
-  is_full = svm_fifo_is_full (rx_fifo);
-
-  if (svm_fifo_is_empty (rx_fifo))
+  if (svm_fifo_is_empty_cons (rx_fifo))
     {
       if (is_nonblocking)
 	{
-	  return VPPCOM_OK;
+	  svm_fifo_unset_event (s->rx_fifo);
+	  return VPPCOM_EWOULDBLOCK;
 	}
-      while (1)
+      while (svm_fifo_is_empty_cons (rx_fifo))
 	{
+	  if (vcl_session_is_closing (s))
+	    return vcl_session_closing_error (s);
+
+	  svm_fifo_unset_event (s->rx_fifo);
 	  svm_msg_q_lock (mq);
 	  if (svm_msg_q_is_empty (mq))
 	    svm_msg_q_wait (mq);
@@ -1310,20 +1639,9 @@ vppcom_session_read_internal (uint32_t session_handle, void *buf, int n,
 	  svm_msg_q_sub_w_lock (mq, &msg);
 	  e = svm_msg_q_msg_data (mq, &msg);
 	  svm_msg_q_unlock (mq);
-	  if (!vcl_is_rx_evt_for_session (e, s->session_index,
-					  s->our_evt_q != 0))
-	    {
-	      vcl_handle_mq_ctrl_event (wrk, e);
-	      svm_msg_q_free_msg (mq, &msg);
-	      continue;
-	    }
-	  svm_fifo_unset_event (rx_fifo);
+	  if (!vcl_is_rx_evt_for_session (e, s->session_index, is_ct))
+	    vcl_handle_mq_event (wrk, e);
 	  svm_msg_q_free_msg (mq, &msg);
-	  if (PREDICT_FALSE (s->session_state == STATE_CLOSE_ON_EMPTY))
-	    return 0;
-	  if (svm_fifo_is_empty (rx_fifo))
-	    continue;
-	  break;
 	}
     }
 
@@ -1332,25 +1650,20 @@ vppcom_session_read_internal (uint32_t session_handle, void *buf, int n,
   else
     n_read = app_recv_stream_raw (rx_fifo, buf, n, 0, peek);
 
-  if (vcl_session_is_ct (s) && is_full)
-    {
-      /* If the peer is not polling send notification */
-      if (!svm_fifo_has_event (s->rx_fifo))
-	app_send_io_evt_to_vpp (s->vpp_evt_q, s->rx_fifo,
-				SESSION_IO_EVT_CT_RX, SVM_Q_WAIT);
-    }
+  if (svm_fifo_is_empty_cons (rx_fifo))
+    svm_fifo_unset_event (s->rx_fifo);
 
-  if (VPPCOM_DEBUG > 2)
+  /* Cut-through sessions might request tx notifications on rx fifos */
+  if (PREDICT_FALSE (rx_fifo->want_deq_ntf))
     {
-      if (n_read > 0)
-	clib_warning ("VCL<%d>: vpp handle 0x%llx, sid %u: read %d bytes "
-		      "from (%p)", getpid (), s->vpp_handle,
-		      session_handle, n_read, rx_fifo);
-      else
-	clib_warning ("VCL<%d>: vpp handle 0x%llx, sid %u: nothing read! "
-		      "returning %d (%s)", getpid (), s->vpp_handle,
-		      session_handle, n_read, vppcom_retval_str (n_read));
+      app_send_io_evt_to_vpp (s->vpp_evt_q, s->rx_fifo->master_session_index,
+			      SESSION_IO_EVT_RX, SVM_Q_WAIT);
+      svm_fifo_reset_has_deq_ntf (s->rx_fifo);
     }
+
+  VDBG (2, "session %u[0x%llx]: read %d bytes from (%p)", s->session_index,
+	s->vpp_handle, n_read, rx_fifo);
+
   return n_read;
 }
 
@@ -1366,58 +1679,113 @@ vppcom_session_peek (uint32_t session_handle, void *buf, int n)
   return (vppcom_session_read_internal (session_handle, buf, n, 1));
 }
 
-static inline int
-vppcom_session_read_ready (vcl_session_t * session)
+int
+vppcom_session_read_segments (uint32_t session_handle,
+			      vppcom_data_segments_t ds)
 {
-  /* Assumes caller has acquired spinlock: vcm->sessions_lockp */
-  if (PREDICT_FALSE (session->is_vep))
-    {
-      clib_warning ("VCL<%d>: ERROR: sid %u: cannot read from an "
-		    "epoll session!", getpid (), session->session_index);
-      return VPPCOM_EBADFD;
-    }
+  vcl_worker_t *wrk = vcl_worker_get_current ();
+  int n_read = 0, is_nonblocking;
+  vcl_session_t *s = 0;
+  svm_fifo_t *rx_fifo;
+  svm_msg_q_msg_t msg;
+  session_event_t *e;
+  svm_msg_q_t *mq;
+  u8 is_ct;
+
+  s = vcl_session_get_w_handle (wrk, session_handle);
+  if (PREDICT_FALSE (!s || s->is_vep))
+    return VPPCOM_EBADFD;
 
-  if (PREDICT_FALSE (!(session->session_state & (STATE_OPEN | STATE_LISTEN))))
+  if (PREDICT_FALSE (!vcl_session_is_open (s)))
+    return vcl_session_closed_error (s);
+
+  is_nonblocking = VCL_SESS_ATTR_TEST (s->attr, VCL_SESS_ATTR_NONBLOCK);
+  is_ct = vcl_session_is_ct (s);
+  mq = is_ct ? s->our_evt_q : wrk->app_event_queue;
+  rx_fifo = s->rx_fifo;
+  s->has_rx_evt = 0;
+
+  if (is_ct)
+    svm_fifo_unset_event (s->rx_fifo);
+
+  if (svm_fifo_is_empty_cons (rx_fifo))
     {
-      session_state_t state = session->session_state;
-      int rv;
+      if (is_nonblocking)
+	{
+	  svm_fifo_unset_event (rx_fifo);
+	  return VPPCOM_EWOULDBLOCK;
+	}
+      while (svm_fifo_is_empty_cons (rx_fifo))
+	{
+	  if (vcl_session_is_closing (s))
+	    return vcl_session_closing_error (s);
 
-      rv = ((state & STATE_DISCONNECT) ? VPPCOM_ECONNRESET : VPPCOM_ENOTCONN);
+	  svm_fifo_unset_event (rx_fifo);
+	  svm_msg_q_lock (mq);
+	  if (svm_msg_q_is_empty (mq))
+	    svm_msg_q_wait (mq);
 
-      VDBG (1, "VCL<%d>: vpp handle 0x%llx, sid %u: session is not open!"
-	    " state 0x%x (%s), returning %d (%s)", getpid (),
-	    session->vpp_handle, session->session_index, state,
-	    vppcom_session_state_str (state), rv, vppcom_retval_str (rv));
-      return rv;
+	  svm_msg_q_sub_w_lock (mq, &msg);
+	  e = svm_msg_q_msg_data (mq, &msg);
+	  svm_msg_q_unlock (mq);
+	  if (!vcl_is_rx_evt_for_session (e, s->session_index, is_ct))
+	    vcl_handle_mq_event (wrk, e);
+	  svm_msg_q_free_msg (mq, &msg);
+	}
     }
 
-  if (session->session_state & STATE_LISTEN)
-    return clib_fifo_elts (session->accept_evts_fifo);
+  n_read = svm_fifo_segments (rx_fifo, (svm_fifo_seg_t *) ds);
+  svm_fifo_unset_event (rx_fifo);
+
+  return n_read;
+}
+
+void
+vppcom_session_free_segments (uint32_t session_handle,
+			      vppcom_data_segments_t ds)
+{
+  vcl_worker_t *wrk = vcl_worker_get_current ();
+  vcl_session_t *s;
+
+  s = vcl_session_get_w_handle (wrk, session_handle);
+  if (PREDICT_FALSE (!s || s->is_vep))
+    return;
+
+  svm_fifo_segments_free (s->rx_fifo, (svm_fifo_seg_t *) ds);
+}
 
-  return svm_fifo_max_dequeue (session->rx_fifo);
+int
+vppcom_data_segment_copy (void *buf, vppcom_data_segments_t ds, u32 max_bytes)
+{
+  u32 first_copy = clib_min (ds[0].len, max_bytes);
+  clib_memcpy_fast (buf, ds[0].data, first_copy);
+  if (first_copy < max_bytes)
+    {
+      clib_memcpy_fast (buf + first_copy, ds[1].data,
+			clib_min (ds[1].len, max_bytes - first_copy));
+    }
+  return 0;
 }
 
 static u8
 vcl_is_tx_evt_for_session (session_event_t * e, u32 sid, u8 is_ct)
 {
-  if (!is_ct)
-    return (e->event_type == FIFO_EVENT_APP_TX
-	    && e->fifo->client_session_index == sid);
-  else
-    return (e->event_type == SESSION_IO_EVT_CT_RX);
+  return (e->event_type == SESSION_IO_EVT_TX && e->session_index == sid);
 }
 
-int
-vppcom_session_write (uint32_t session_handle, void *buf, size_t n)
+static inline int
+vppcom_session_write_inline (uint32_t session_handle, void *buf, size_t n,
+			     u8 is_flush)
 {
   vcl_worker_t *wrk = vcl_worker_get_current ();
-  int rv, n_write, is_nonblocking;
+  int n_write, is_nonblocking;
   vcl_session_t *s = 0;
-  svm_fifo_t *tx_fifo = 0;
   session_evt_type_t et;
   svm_msg_q_msg_t msg;
+  svm_fifo_t *tx_fifo;
   session_event_t *e;
   svm_msg_q_t *mq;
+  u8 is_ct;
 
   if (PREDICT_FALSE (!buf))
     return VPPCOM_EINVAL;
@@ -1426,158 +1794,191 @@ vppcom_session_write (uint32_t session_handle, void *buf, size_t n)
   if (PREDICT_FALSE (!s))
     return VPPCOM_EBADFD;
 
-  tx_fifo = s->tx_fifo;
-  is_nonblocking = VCL_SESS_ATTR_TEST (s->attr, VCL_SESS_ATTR_NONBLOCK);
-
   if (PREDICT_FALSE (s->is_vep))
     {
-      clib_warning ("VCL<%d>: ERROR: vpp handle 0x%llx, sid %u: "
-		    "cannot write to an epoll session!",
-		    getpid (), s->vpp_handle, session_handle);
-
+      VDBG (0, "ERROR: session %u [0x%llx]: cannot write to an epoll"
+	    " session!", s->session_index, s->vpp_handle);
       return VPPCOM_EBADFD;
     }
 
-  if (!(s->session_state & STATE_OPEN))
+  if (PREDICT_FALSE (!vcl_session_is_open (s)))
     {
-      session_state_t state = s->session_state;
-      rv = ((state & STATE_DISCONNECT) ? VPPCOM_ECONNRESET : VPPCOM_ENOTCONN);
-      VDBG (1, "VCL<%d>: vpp handle 0x%llx, sid %u: session is not open! "
-	    "state 0x%x (%s)",
-	    getpid (), s->vpp_handle, session_handle,
-	    state, vppcom_session_state_str (state));
-      return rv;
+      VDBG (1, "session %u [0x%llx]: is not open! state 0x%x (%s)",
+	    s->session_index, s->vpp_handle, s->session_state,
+	    vppcom_session_state_str (s->session_state));
+      return vcl_session_closed_error (s);;
     }
 
-  mq = vcl_session_is_ct (s) ? s->our_evt_q : wrk->app_event_queue;
-  if (svm_fifo_is_full (tx_fifo))
+  is_ct = vcl_session_is_ct (s);
+  tx_fifo = is_ct ? s->ct_tx_fifo : s->tx_fifo;
+  is_nonblocking = VCL_SESS_ATTR_TEST (s->attr, VCL_SESS_ATTR_NONBLOCK);
+
+  mq = wrk->app_event_queue;
+  if (svm_fifo_is_full_prod (tx_fifo))
     {
       if (is_nonblocking)
 	{
 	  return VPPCOM_EWOULDBLOCK;
 	}
-      while (svm_fifo_is_full (tx_fifo))
+      while (svm_fifo_is_full_prod (tx_fifo))
 	{
+	  svm_fifo_add_want_deq_ntf (tx_fifo, SVM_FIFO_WANT_DEQ_NOTIF);
+	  if (vcl_session_is_closing (s))
+	    return vcl_session_closing_error (s);
 	  svm_msg_q_lock (mq);
-	  while (svm_msg_q_is_empty (mq) && svm_msg_q_timedwait (mq, 10e-6))
-	    ;
+	  if (svm_msg_q_is_empty (mq))
+	    svm_msg_q_wait (mq);
+
 	  svm_msg_q_sub_w_lock (mq, &msg);
 	  e = svm_msg_q_msg_data (mq, &msg);
 	  svm_msg_q_unlock (mq);
 
-	  if (!vcl_is_tx_evt_for_session (e, s->session_index,
-					  s->our_evt_q != 0))
-	    vcl_handle_mq_ctrl_event (wrk, e);
+	  if (!vcl_is_tx_evt_for_session (e, s->session_index, is_ct))
+	    vcl_handle_mq_event (wrk, e);
 	  svm_msg_q_free_msg (mq, &msg);
 	}
     }
 
-  ASSERT (FIFO_EVENT_APP_TX + 1 == SESSION_IO_EVT_CT_TX);
-  et = FIFO_EVENT_APP_TX + vcl_session_is_ct (s);
+  et = SESSION_IO_EVT_TX;
+  if (is_flush && !is_ct)
+    et = SESSION_IO_EVT_TX_FLUSH;
+
   if (s->is_dgram)
     n_write = app_send_dgram_raw (tx_fifo, &s->transport,
-				  s->vpp_evt_q, buf, n, et, SVM_Q_WAIT);
+				  s->vpp_evt_q, buf, n, et,
+				  0 /* do_evt */ , SVM_Q_WAIT);
   else
     n_write = app_send_stream_raw (tx_fifo, s->vpp_evt_q, buf, n, et,
-				   SVM_Q_WAIT);
+				   0 /* do_evt */ , SVM_Q_WAIT);
+
+  if (svm_fifo_set_event (s->tx_fifo))
+    app_send_io_evt_to_vpp (s->vpp_evt_q, s->tx_fifo->master_session_index,
+			    et, SVM_Q_WAIT);
 
   ASSERT (n_write > 0);
 
-  if (VPPCOM_DEBUG > 2)
-    {
-      if (n_write <= 0)
-	clib_warning ("VCL<%d>: vpp handle 0x%llx, sid %u: "
-		      "FIFO-FULL (%p)", getpid (), s->vpp_handle,
-		      session_handle, tx_fifo);
-      else
-	clib_warning ("VCL<%d>: vpp handle 0x%llx, sid %u: "
-		      "wrote %d bytes tx-fifo: (%p)", getpid (),
-		      s->vpp_handle, session_handle, n_write, tx_fifo);
-    }
+  VDBG (2, "session %u [0x%llx]: wrote %d bytes", s->session_index,
+	s->vpp_handle, n_write);
+
   return n_write;
 }
 
-static vcl_session_t *
-vcl_ct_session_get_from_fifo (vcl_worker_t * wrk, svm_fifo_t * f, u8 type)
+int
+vppcom_session_write (uint32_t session_handle, void *buf, size_t n)
 {
-  vcl_session_t *s;
-  s = vcl_session_get (wrk, f->client_session_index);
-  if (s)
-    {
-      /* rx fifo */
-      if (type == 0 && s->rx_fifo == f)
-	return s;
-      /* tx fifo */
-      if (type == 1 && s->tx_fifo == f)
-	return s;
-    }
-  s = vcl_session_get (wrk, f->master_session_index);
-  if (s)
-    {
-      if (type == 0 && s->rx_fifo == f)
-	return s;
-      if (type == 1 && s->tx_fifo == f)
-	return s;
-    }
-  return 0;
+  return vppcom_session_write_inline (session_handle, buf, n,
+				      0 /* is_flush */ );
 }
 
-static inline int
-vppcom_session_write_ready (vcl_session_t * session)
+int
+vppcom_session_write_msg (uint32_t session_handle, void *buf, size_t n)
 {
-  /* Assumes caller has acquired spinlock: vcm->sessions_lockp */
-  if (PREDICT_FALSE (session->is_vep))
-    {
-      clib_warning ("VCL<%d>: ERROR: vpp handle 0x%llx, sid %u: "
-		    "cannot write to an epoll session!",
-		    getpid (), session->vpp_handle, session->session_index);
-      return VPPCOM_EBADFD;
-    }
-
-  if (PREDICT_FALSE (session->session_state & STATE_LISTEN))
-    {
-      clib_warning ("VCL<%d>: ERROR: vpp handle 0x%llx, sid %u: "
-		    "cannot write to a listen session!",
-		    getpid (), session->vpp_handle, session->session_index);
-      return VPPCOM_EBADFD;
-    }
-
-  if (PREDICT_FALSE (!(session->session_state & STATE_OPEN)))
-    {
-      session_state_t state = session->session_state;
-      int rv;
-
-      rv = ((state & STATE_DISCONNECT) ? VPPCOM_ECONNRESET : VPPCOM_ENOTCONN);
-      clib_warning ("VCL<%d>: ERROR: vpp handle 0x%llx, sid %u: "
-		    "session is not open! state 0x%x (%s), "
-		    "returning %d (%s)", getpid (), session->vpp_handle,
-		    session->session_index,
-		    state, vppcom_session_state_str (state),
-		    rv, vppcom_retval_str (rv));
-      return rv;
-    }
-
-  VDBG (3, "VCL<%d>: vpp handle 0x%llx, sid %u: peek %s (%p), ready = %d",
-	getpid (), session->vpp_handle, session->session_index,
-	session->tx_fifo, svm_fifo_max_enqueue (session->tx_fifo));
-
-  return svm_fifo_max_enqueue (session->tx_fifo);
+  return vppcom_session_write_inline (session_handle, buf, n,
+				      1 /* is_flush */ );
 }
 
-static inline int
-vcl_mq_dequeue_batch (vcl_worker_t * wrk, svm_msg_q_t * mq)
+#define vcl_fifo_rx_evt_valid_or_break(_s)				\
+if (PREDICT_FALSE (svm_fifo_is_empty (_s->rx_fifo)))			\
+  {									\
+    if (!vcl_session_is_ct (_s))					\
+      {									\
+	svm_fifo_unset_event (_s->rx_fifo);				\
+	if (svm_fifo_is_empty (_s->rx_fifo))				\
+	  break;							\
+      }									\
+    else if (svm_fifo_is_empty (_s->ct_rx_fifo))			\
+      {									\
+	svm_fifo_unset_event (_s->ct_rx_fifo);				\
+	if (svm_fifo_is_empty (_s->ct_rx_fifo))				\
+	  break;							\
+      }									\
+  }									\
+
+static void
+vcl_select_handle_mq_event (vcl_worker_t * wrk, session_event_t * e,
+			    unsigned long n_bits, unsigned long *read_map,
+			    unsigned long *write_map,
+			    unsigned long *except_map, u32 * bits_set)
 {
-  svm_msg_q_msg_t *msg;
-  u32 n_msgs;
-  int i;
+  session_disconnected_msg_t *disconnected_msg;
+  session_connected_msg_t *connected_msg;
+  vcl_session_t *session;
+  u32 sid;
 
-  n_msgs = svm_msg_q_size (mq);
-  for (i = 0; i < n_msgs; i++)
+  switch (e->event_type)
     {
-      vec_add2 (wrk->mq_msg_vector, msg, 1);
-      svm_msg_q_sub_w_lock (mq, msg);
+    case SESSION_IO_EVT_RX:
+      sid = e->session_index;
+      session = vcl_session_get (wrk, sid);
+      if (!session)
+	break;
+      vcl_fifo_rx_evt_valid_or_break (session);
+      if (sid < n_bits && read_map)
+	{
+	  clib_bitmap_set_no_check ((uword *) read_map, sid, 1);
+	  *bits_set += 1;
+	}
+      break;
+    case SESSION_IO_EVT_TX:
+      sid = e->session_index;
+      session = vcl_session_get (wrk, sid);
+      if (!session)
+	break;
+      if (sid < n_bits && write_map)
+	{
+	  clib_bitmap_set_no_check ((uword *) write_map, sid, 1);
+	  *bits_set += 1;
+	}
+      break;
+    case SESSION_CTRL_EVT_ACCEPTED:
+      session = vcl_session_accepted (wrk,
+				      (session_accepted_msg_t *) e->data);
+      if (!session)
+	break;
+      sid = session->session_index;
+      if (sid < n_bits && read_map)
+	{
+	  clib_bitmap_set_no_check ((uword *) read_map, sid, 1);
+	  *bits_set += 1;
+	}
+      break;
+    case SESSION_CTRL_EVT_CONNECTED:
+      connected_msg = (session_connected_msg_t *) e->data;
+      vcl_session_connected_handler (wrk, connected_msg);
+      break;
+    case SESSION_CTRL_EVT_DISCONNECTED:
+      disconnected_msg = (session_disconnected_msg_t *) e->data;
+      session = vcl_session_disconnected_handler (wrk, disconnected_msg);
+      if (!session)
+	break;
+      sid = session->session_index;
+      if (sid < n_bits && except_map)
+	{
+	  clib_bitmap_set_no_check ((uword *) except_map, sid, 1);
+	  *bits_set += 1;
+	}
+      break;
+    case SESSION_CTRL_EVT_RESET:
+      sid = vcl_session_reset_handler (wrk, (session_reset_msg_t *) e->data);
+      if (sid < n_bits && except_map)
+	{
+	  clib_bitmap_set_no_check ((uword *) except_map, sid, 1);
+	  *bits_set += 1;
+	}
+      break;
+    case SESSION_CTRL_EVT_UNLISTEN_REPLY:
+      vcl_session_unlisten_reply_handler (wrk, e->data);
+      break;
+    case SESSION_CTRL_EVT_WORKER_UPDATE_REPLY:
+      vcl_session_worker_update_reply_handler (wrk, e->data);
+      break;
+    case SESSION_CTRL_EVT_REQ_WORKER_UPDATE:
+      vcl_session_req_worker_update_handler (wrk, e->data);
+      break;
+    default:
+      clib_warning ("unhandled: %u", e->event_type);
+      break;
     }
-  return n_msgs;
 }
 
 static int
@@ -1586,15 +1987,9 @@ vcl_select_handle_mq (vcl_worker_t * wrk, svm_msg_q_t * mq,
 		      unsigned long *write_map, unsigned long *except_map,
 		      double time_to_wait, u32 * bits_set)
 {
-  session_disconnected_msg_t *disconnected_msg;
-  session_connected_msg_t *connected_msg;
-  session_accepted_msg_t *accepted_msg;
-  vcl_session_msg_t *vcl_msg;
-  vcl_session_t *session;
   svm_msg_q_msg_t *msg;
   session_event_t *e;
-  u32 i, sid;
-  u64 handle;
+  u32 i;
 
   svm_msg_q_lock (mq);
   if (svm_msg_q_is_empty (mq))
@@ -1623,156 +2018,56 @@ vcl_select_handle_mq (vcl_worker_t * wrk, svm_msg_q_t * mq,
 	    }
 	}
     }
-  vcl_mq_dequeue_batch (wrk, mq);
+  vcl_mq_dequeue_batch (wrk, mq, ~0);
   svm_msg_q_unlock (mq);
 
   for (i = 0; i < vec_len (wrk->mq_msg_vector); i++)
     {
       msg = vec_elt_at_index (wrk->mq_msg_vector, i);
       e = svm_msg_q_msg_data (mq, msg);
-      switch (e->event_type)
-	{
-	case FIFO_EVENT_APP_RX:
-	  sid = e->fifo->client_session_index;
-	  session = vcl_session_get (wrk, sid);
-	  if (!session)
-	    break;
-	  if (sid < n_bits && read_map)
-	    {
-	      clib_bitmap_set_no_check (read_map, sid, 1);
-	      *bits_set += 1;
-	    }
-	  break;
-	case FIFO_EVENT_APP_TX:
-	  sid = e->fifo->client_session_index;
-	  session = vcl_session_get (wrk, sid);
-	  if (!session)
-	    break;
-	  if (sid < n_bits && write_map)
-	    {
-	      clib_bitmap_set_no_check (write_map, sid, 1);
-	      *bits_set += 1;
-	    }
-	  break;
-	case SESSION_IO_EVT_CT_TX:
-	  if (svm_fifo_is_empty (e->fifo))
-	    {
-	      svm_fifo_unset_event (e->fifo);
-	      if (svm_fifo_is_empty (e->fifo))
-		break;
-	    }
-	  session = vcl_ct_session_get_from_fifo (wrk, e->fifo, 0);
-	  if (!session)
-	    break;
-	  sid = session->session_index;
-	  if (sid < n_bits && read_map)
-	    {
-	      clib_bitmap_set_no_check (read_map, sid, 1);
-	      *bits_set += 1;
-	    }
-	  break;
-	case SESSION_IO_EVT_CT_RX:
-	  session = vcl_ct_session_get_from_fifo (wrk, e->fifo, 1);
-	  if (!session)
-	    break;
-	  sid = session->session_index;
-	  if (sid < n_bits && write_map)
-	    {
-	      clib_bitmap_set_no_check (write_map, sid, 1);
-	      *bits_set += 1;
-	    }
-	  break;
-	case SESSION_CTRL_EVT_ACCEPTED:
-	  accepted_msg = (session_accepted_msg_t *) e->data;
-	  handle = accepted_msg->listener_handle;
-	  session = vcl_session_table_lookup_listener (wrk, handle);
-	  if (!session)
-	    {
-	      clib_warning ("VCL<%d>: ERROR: couldn't find listen session:"
-			    "listener handle %llx", getpid (), handle);
-	      break;
-	    }
-
-	  clib_fifo_add2 (session->accept_evts_fifo, vcl_msg);
-	  vcl_msg->accepted_msg = *accepted_msg;
-	  sid = session->session_index;
-	  if (sid < n_bits && read_map)
-	    {
-	      clib_bitmap_set_no_check (read_map, sid, 1);
-	      *bits_set += 1;
-	    }
-	  break;
-	case SESSION_CTRL_EVT_CONNECTED:
-	  connected_msg = (session_connected_msg_t *) e->data;
-	  vcl_session_connected_handler (wrk, connected_msg);
-	  break;
-	case SESSION_CTRL_EVT_DISCONNECTED:
-	  disconnected_msg = (session_disconnected_msg_t *) e->data;
-	  sid = vcl_session_index_from_vpp_handle (wrk,
-						   disconnected_msg->handle);
-	  if (sid < n_bits && except_map)
-	    {
-	      clib_bitmap_set_no_check (except_map, sid, 1);
-	      *bits_set += 1;
-	    }
-	  break;
-	case SESSION_CTRL_EVT_RESET:
-	  sid = vcl_session_reset_handler (wrk,
-					   (session_reset_msg_t *) e->data);
-	  if (sid < n_bits && except_map)
-	    {
-	      clib_bitmap_set_no_check (except_map, sid, 1);
-	      *bits_set += 1;
-	    }
-	  break;
-	default:
-	  clib_warning ("unhandled: %u", e->event_type);
-	  break;
-	}
+      vcl_select_handle_mq_event (wrk, e, n_bits, read_map, write_map,
+				  except_map, bits_set);
       svm_msg_q_free_msg (mq, msg);
     }
-
   vec_reset_length (wrk->mq_msg_vector);
+  vcl_handle_pending_wrk_updates (wrk);
   return *bits_set;
 }
 
 static int
-vppcom_select_condvar (vcl_worker_t * wrk, unsigned long n_bits,
-		       unsigned long *read_map, unsigned long *write_map,
-		       unsigned long *except_map, double time_to_wait,
+vppcom_select_condvar (vcl_worker_t * wrk, int n_bits,
+		       vcl_si_set * read_map, vcl_si_set * write_map,
+		       vcl_si_set * except_map, double time_to_wait,
 		       u32 * bits_set)
 {
-  double total_wait = 0, wait_slice;
-  vcl_cut_through_registration_t *cr;
+  double wait = 0, start = 0;
 
-  time_to_wait = (time_to_wait == -1) ? 10e9 : time_to_wait;
-  wait_slice = wrk->cut_through_registrations ? 10e-6 : time_to_wait;
-  do
+  if (!*bits_set)
     {
-      vcl_ct_registration_lock (wrk);
-      /* *INDENT-OFF* */
-      pool_foreach (cr, wrk->cut_through_registrations, ({
-	vcl_select_handle_mq (wrk, cr->mq, n_bits, read_map, write_map, except_map,
-	                      0, bits_set);
-      }));
-      /* *INDENT-ON* */
-      vcl_ct_registration_unlock (wrk);
+      wait = time_to_wait;
+      start = clib_time_now (&wrk->clib_time);
+    }
 
+  do
+    {
       vcl_select_handle_mq (wrk, wrk->app_event_queue, n_bits, read_map,
-			    write_map, except_map, time_to_wait, bits_set);
-      total_wait += wait_slice;
+			    write_map, except_map, wait, bits_set);
       if (*bits_set)
 	return *bits_set;
+      if (wait == -1)
+	continue;
+
+      wait = wait - (clib_time_now (&wrk->clib_time) - start);
     }
-  while (total_wait < time_to_wait);
+  while (wait > 0);
 
   return 0;
 }
 
 static int
-vppcom_select_eventfd (vcl_worker_t * wrk, unsigned long n_bits,
-		       unsigned long *read_map, unsigned long *write_map,
-		       unsigned long *except_map, double time_to_wait,
+vppcom_select_eventfd (vcl_worker_t * wrk, int n_bits,
+		       vcl_si_set * read_map, vcl_si_set * write_map,
+		       vcl_si_set * except_map, double time_to_wait,
 		       u32 * bits_set)
 {
   vcl_mq_evt_conn_t *mqc;
@@ -1795,39 +2090,34 @@ vppcom_select_eventfd (vcl_worker_t * wrk, unsigned long n_bits,
 }
 
 int
-vppcom_select (unsigned long n_bits, unsigned long *read_map,
-	       unsigned long *write_map, unsigned long *except_map,
-	       double time_to_wait)
+vppcom_select (int n_bits, vcl_si_set * read_map, vcl_si_set * write_map,
+	       vcl_si_set * except_map, double time_to_wait)
 {
   u32 sid, minbits = clib_max (n_bits, BITS (uword)), bits_set = 0;
   vcl_worker_t *wrk = vcl_worker_get_current ();
   vcl_session_t *session = 0;
-  int rv;
-
-  ASSERT (sizeof (clib_bitmap_t) == sizeof (long int));
+  int rv, i;
 
   if (n_bits && read_map)
     {
       clib_bitmap_validate (wrk->rd_bitmap, minbits);
-      clib_memcpy (wrk->rd_bitmap, read_map,
-		   vec_len (wrk->rd_bitmap) * sizeof (clib_bitmap_t));
-      memset (read_map, 0, vec_len (wrk->rd_bitmap) * sizeof (clib_bitmap_t));
+      clib_memcpy_fast (wrk->rd_bitmap, read_map,
+			vec_len (wrk->rd_bitmap) * sizeof (vcl_si_set));
+      memset (read_map, 0, vec_len (wrk->rd_bitmap) * sizeof (vcl_si_set));
     }
   if (n_bits && write_map)
     {
       clib_bitmap_validate (wrk->wr_bitmap, minbits);
-      clib_memcpy (wrk->wr_bitmap, write_map,
-		   vec_len (wrk->wr_bitmap) * sizeof (clib_bitmap_t));
-      memset (write_map, 0,
-	      vec_len (wrk->wr_bitmap) * sizeof (clib_bitmap_t));
+      clib_memcpy_fast (wrk->wr_bitmap, write_map,
+			vec_len (wrk->wr_bitmap) * sizeof (vcl_si_set));
+      memset (write_map, 0, vec_len (wrk->wr_bitmap) * sizeof (vcl_si_set));
     }
   if (n_bits && except_map)
     {
       clib_bitmap_validate (wrk->ex_bitmap, minbits);
-      clib_memcpy (wrk->ex_bitmap, except_map,
-		   vec_len (wrk->ex_bitmap) * sizeof (clib_bitmap_t));
-      memset (except_map, 0,
-	      vec_len (wrk->ex_bitmap) * sizeof (clib_bitmap_t));
+      clib_memcpy_fast (wrk->ex_bitmap, except_map,
+			vec_len (wrk->ex_bitmap) * sizeof (vcl_si_set));
+      memset (except_map, 0, vec_len (wrk->ex_bitmap) * sizeof (vcl_si_set));
     }
 
   if (!n_bits)
@@ -1840,17 +2130,19 @@ vppcom_select (unsigned long n_bits, unsigned long *read_map,
   clib_bitmap_foreach (sid, wrk->wr_bitmap, ({
     if (!(session = vcl_session_get (wrk, sid)))
       {
-        VDBG (0, "VCL<%d>: session %d specified in write_map is closed.",
-              getpid (), sid);
-        return VPPCOM_EBADFD;
+        if (except_map && sid < minbits)
+          clib_bitmap_set_no_check (except_map, sid, 1);
+        continue;
       }
 
-    rv = svm_fifo_is_full (session->tx_fifo);
+    rv = svm_fifo_is_full_prod (session->tx_fifo);
     if (!rv)
       {
-        clib_bitmap_set_no_check (write_map, sid, 1);
+        clib_bitmap_set_no_check ((uword*)write_map, sid, 1);
         bits_set++;
       }
+    else
+      svm_fifo_add_want_deq_ntf (session->tx_fifo, SVM_FIFO_WANT_DEQ_NOTIF);
   }));
 
 check_rd:
@@ -1860,15 +2152,15 @@ check_rd:
   clib_bitmap_foreach (sid, wrk->rd_bitmap, ({
     if (!(session = vcl_session_get (wrk, sid)))
       {
-        VDBG (0, "VCL<%d>: session %d specified in write_map is closed.",
-              getpid (), sid);
-        return VPPCOM_EBADFD;
+        if (except_map && sid < minbits)
+          clib_bitmap_set_no_check (except_map, sid, 1);
+        continue;
       }
 
-    rv = vppcom_session_read_ready (session);
+    rv = vcl_session_read_ready (session);
     if (rv)
       {
-        clib_bitmap_set_no_check (read_map, sid, 1);
+        clib_bitmap_set_no_check ((uword*)read_map, sid, 1);
         bits_set++;
       }
   }));
@@ -1876,6 +2168,13 @@ check_rd:
 
 check_mq:
 
+  for (i = 0; i < vec_len (wrk->unhandled_evts_vector); i++)
+    {
+      vcl_select_handle_mq_event (wrk, &wrk->unhandled_evts_vector[i], n_bits,
+				  read_map, write_map, except_map, &bits_set);
+    }
+  vec_reset_length (wrk->unhandled_evts_vector);
+
   if (vcm->cfg.use_mq_eventfd)
     vppcom_select_eventfd (wrk, n_bits, read_map, write_map, except_map,
 			   time_to_wait, &bits_set);
@@ -1893,79 +2192,69 @@ vep_verify_epoll_chain (vcl_worker_t * wrk, u32 vep_idx)
   vppcom_epoll_t *vep;
   u32 sid = vep_idx;
 
-  if (VPPCOM_DEBUG <= 1)
+  if (VPPCOM_DEBUG <= 2)
     return;
 
-  /* Assumes caller has acquired spinlock: vcm->sessions_lockp */
   session = vcl_session_get (wrk, vep_idx);
   if (PREDICT_FALSE (!session))
     {
-      clib_warning ("VCL<%d>: ERROR: Invalid vep_idx (%u)!",
-		    getpid (), vep_idx);
+      VDBG (0, "ERROR: Invalid vep_idx (%u)!", vep_idx);
       goto done;
     }
   if (PREDICT_FALSE (!session->is_vep))
     {
-      clib_warning ("VCL<%d>: ERROR: vep_idx (%u) is not a vep!",
-		    getpid (), vep_idx);
+      VDBG (0, "ERROR: vep_idx (%u) is not a vep!", vep_idx);
       goto done;
     }
   vep = &session->vep;
-  clib_warning ("VCL<%d>: vep_idx (%u): Dumping epoll chain\n"
-		"{\n"
-		"   is_vep         = %u\n"
-		"   is_vep_session = %u\n"
-		"   next_sid       = 0x%x (%u)\n"
-		"   wait_cont_idx  = 0x%x (%u)\n"
-		"}\n", getpid (), vep_idx,
-		session->is_vep, session->is_vep_session,
-		vep->next_sh, vep->next_sh,
-		session->wait_cont_idx, session->wait_cont_idx);
+  VDBG (0, "vep_idx (%u): Dumping epoll chain\n"
+	"{\n"
+	"   is_vep         = %u\n"
+	"   is_vep_session = %u\n"
+	"   next_sid       = 0x%x (%u)\n"
+	"}\n", vep_idx, session->is_vep, session->is_vep_session,
+	vep->next_sh, vep->next_sh);
 
   for (sid = vep->next_sh; sid != ~0; sid = vep->next_sh)
     {
       session = vcl_session_get (wrk, sid);
       if (PREDICT_FALSE (!session))
 	{
-	  clib_warning ("VCL<%d>: ERROR: Invalid sid (%u)!", getpid (), sid);
+	  VDBG (0, "ERROR: Invalid sid (%u)!", sid);
 	  goto done;
 	}
       if (PREDICT_FALSE (session->is_vep))
-	clib_warning ("VCL<%d>: ERROR: sid (%u) is a vep!",
-		      getpid (), vep_idx);
+	{
+	  VDBG (0, "ERROR: sid (%u) is a vep!", vep_idx);
+	}
       else if (PREDICT_FALSE (!session->is_vep_session))
 	{
-	  clib_warning ("VCL<%d>: ERROR: session (%u) "
-			"is not a vep session!", getpid (), sid);
+	  VDBG (0, "ERROR: session (%u) is not a vep session!", sid);
 	  goto done;
 	}
       vep = &session->vep;
       if (PREDICT_FALSE (vep->vep_sh != vep_idx))
-	clib_warning ("VCL<%d>: ERROR: session (%u) vep_idx (%u) != "
-		      "vep_idx (%u)!", getpid (),
-		      sid, session->vep.vep_sh, vep_idx);
+	VDBG (0, "ERROR: session (%u) vep_idx (%u) != vep_idx (%u)!",
+	      sid, session->vep.vep_sh, vep_idx);
       if (session->is_vep_session)
 	{
-	  clib_warning ("vep_idx[%u]: sid 0x%x (%u)\n"
-			"{\n"
-			"   next_sid       = 0x%x (%u)\n"
-			"   prev_sid       = 0x%x (%u)\n"
-			"   vep_idx        = 0x%x (%u)\n"
-			"   ev.events      = 0x%x\n"
-			"   ev.data.u64    = 0x%llx\n"
-			"   et_mask        = 0x%x\n"
-			"}\n",
-			vep_idx, sid, sid,
-			vep->next_sh, vep->next_sh,
-			vep->prev_sh, vep->prev_sh,
-			vep->vep_sh, vep->vep_sh,
-			vep->ev.events, vep->ev.data.u64, vep->et_mask);
+	  VDBG (0, "vep_idx[%u]: sid 0x%x (%u)\n"
+		"{\n"
+		"   next_sid       = 0x%x (%u)\n"
+		"   prev_sid       = 0x%x (%u)\n"
+		"   vep_idx        = 0x%x (%u)\n"
+		"   ev.events      = 0x%x\n"
+		"   ev.data.u64    = 0x%llx\n"
+		"   et_mask        = 0x%x\n"
+		"}\n",
+		vep_idx, sid, sid, vep->next_sh, vep->next_sh, vep->prev_sh,
+		vep->prev_sh, vep->vep_sh, vep->vep_sh, vep->ev.events,
+		vep->ev.data.u64, vep->et_mask);
 	}
     }
 
 done:
-  clib_warning ("VCL<%d>: vep_idx (%u): Dump complete!\n",
-		getpid (), vep_idx);
+  VDBG (0, "vep_idx (%u): Dump complete!\n", vep_idx);
 }
 
 int
@@ -1980,12 +2269,10 @@ vppcom_epoll_create (void)
   vep_session->vep.vep_sh = ~0;
   vep_session->vep.next_sh = ~0;
   vep_session->vep.prev_sh = ~0;
-  vep_session->wait_cont_idx = ~0;
   vep_session->vpp_handle = ~0;
 
-  vcl_evt (VCL_EVT_EPOLL_CREATE, vep_session, vep_sh);
-  VDBG (0, "VCL<%d>: Created vep_idx %u / sid %u!",
-	getpid (), vep_session->session_index, vep_session->session_index);
+  vcl_evt (VCL_EVT_EPOLL_CREATE, vep_session, vep_session->session_index);
+  VDBG (0, "Created vep_idx %u", vep_session->session_index);
 
   return vcl_session_handle (vep_session);
 }
@@ -2001,21 +2288,19 @@ vppcom_epoll_ctl (uint32_t vep_handle, int op, uint32_t session_handle,
 
   if (vep_handle == session_handle)
     {
-      clib_warning ("VCL<%d>: ERROR: vep_idx == session_index (%u)!",
-		    getpid (), vep_handle);
+      VDBG (0, "vep_sh == session handle (%u)!", vep_handle);
       return VPPCOM_EINVAL;
     }
 
   vep_session = vcl_session_get_w_handle (wrk, vep_handle);
   if (PREDICT_FALSE (!vep_session))
     {
-      clib_warning ("VCL<%d>: ERROR: Invalid vep_idx (%u)!", vep_handle);
+      VDBG (0, "Invalid vep_sh (%u)!", vep_handle);
       return VPPCOM_EBADFD;
     }
   if (PREDICT_FALSE (!vep_session->is_vep))
     {
-      clib_warning ("VCL<%d>: ERROR: vep_idx (%u) is not a vep!",
-		    getpid (), vep_handle);
+      VDBG (0, "vep_sh (%u) is not a vep!", vep_handle);
       return VPPCOM_EINVAL;
     }
 
@@ -2025,13 +2310,12 @@ vppcom_epoll_ctl (uint32_t vep_handle, int op, uint32_t session_handle,
   session = vcl_session_get_w_handle (wrk, session_handle);
   if (PREDICT_FALSE (!session))
     {
-      VDBG (0, "VCL<%d>: ERROR: Invalid session_handle (%u)!",
-	    getpid (), session_handle);
+      VDBG (0, "Invalid session_handle (%u)!", session_handle);
       return VPPCOM_EBADFD;
     }
   if (PREDICT_FALSE (session->is_vep))
     {
-      clib_warning ("ERROR: session_handle (%u) is a vep!", vep_handle);
+      VDBG (0, "session_handle (%u) is a vep!", vep_handle);
       return VPPCOM_EINVAL;
     }
 
@@ -2040,8 +2324,7 @@ vppcom_epoll_ctl (uint32_t vep_handle, int op, uint32_t session_handle,
     case EPOLL_CTL_ADD:
       if (PREDICT_FALSE (!event))
 	{
-	  clib_warning ("VCL<%d>: ERROR: EPOLL_CTL_ADD: NULL pointer to "
-			"epoll_event structure!", getpid ());
+	  VDBG (0, "EPOLL_CTL_ADD: NULL pointer to epoll_event structure!");
 	  return VPPCOM_EINVAL;
 	}
       if (vep_session->vep.next_sh != ~0)
@@ -2051,9 +2334,8 @@ vppcom_epoll_ctl (uint32_t vep_handle, int op, uint32_t session_handle,
 						   vep_session->vep.next_sh);
 	  if (PREDICT_FALSE (!next_session))
 	    {
-	      clib_warning ("VCL<%d>: ERROR: EPOLL_CTL_ADD: Invalid "
-			    "vep.next_sid (%u) on vep_idx (%u)!",
-			    getpid (), vep_session->vep.next_sh, vep_handle);
+	      VDBG (0, "EPOLL_CTL_ADD: Invalid vep.next_sh (%u) on "
+		    "vep_idx (%u)!", vep_session->vep.next_sh, vep_handle);
 	      return VPPCOM_EBADFD;
 	    }
 	  ASSERT (next_session->vep.prev_sh == vep_handle);
@@ -2068,65 +2350,56 @@ vppcom_epoll_ctl (uint32_t vep_handle, int op, uint32_t session_handle,
       session->is_vep_session = 1;
       vep_session->vep.next_sh = session_handle;
 
-      VDBG (1, "VCL<%d>: EPOLL_CTL_ADD: vep_idx %u, sid %u, events 0x%x, "
-	    "data 0x%llx!", getpid (), vep_handle, session_handle,
-	    event->events, event->data.u64);
+      if (session->tx_fifo)
+	svm_fifo_add_want_deq_ntf (session->tx_fifo,
+				   SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);
+
+      VDBG (1, "EPOLL_CTL_ADD: vep_sh %u, sh %u, events 0x%x, data 0x%llx!",
+	    vep_handle, session_handle, event->events, event->data.u64);
       vcl_evt (VCL_EVT_EPOLL_CTLADD, session, event->events, event->data.u64);
       break;
 
     case EPOLL_CTL_MOD:
       if (PREDICT_FALSE (!event))
 	{
-	  clib_warning ("VCL<%d>: ERROR: EPOLL_CTL_MOD: NULL pointer to "
-			"epoll_event structure!", getpid ());
+	  VDBG (0, "EPOLL_CTL_MOD: NULL pointer to epoll_event structure!");
 	  rv = VPPCOM_EINVAL;
 	  goto done;
 	}
       else if (PREDICT_FALSE (!session->is_vep_session))
 	{
-	  clib_warning ("VCL<%d>: ERROR: sid %u EPOLL_CTL_MOD: "
-			"not a vep session!", getpid (), session_handle);
+	  VDBG (0, "sh %u EPOLL_CTL_MOD: not a vep session!", session_handle);
 	  rv = VPPCOM_EINVAL;
 	  goto done;
 	}
       else if (PREDICT_FALSE (session->vep.vep_sh != vep_handle))
 	{
-	  clib_warning ("VCL<%d>: ERROR: sid %u EPOLL_CTL_MOD: "
-			"vep_idx (%u) != vep_idx (%u)!",
-			getpid (), session_handle,
-			session->vep.vep_sh, vep_handle);
+	  VDBG (0, "EPOLL_CTL_MOD: sh %u vep_sh (%u) != vep_sh (%u)!",
+		session_handle, session->vep.vep_sh, vep_handle);
 	  rv = VPPCOM_EINVAL;
 	  goto done;
 	}
       session->vep.et_mask = VEP_DEFAULT_ET_MASK;
       session->vep.ev = *event;
-      VDBG (1, "VCL<%d>: EPOLL_CTL_MOD: vep_idx %u, sid %u, events 0x%x,"
-	    " data 0x%llx!", getpid (), vep_handle, session_handle,
-	    event->events, event->data.u64);
+      VDBG (1, "EPOLL_CTL_MOD: vep_sh %u, sh %u, events 0x%x, data 0x%llx!",
+	    vep_handle, session_handle, event->events, event->data.u64);
       break;
 
     case EPOLL_CTL_DEL:
       if (PREDICT_FALSE (!session->is_vep_session))
 	{
-	  clib_warning ("VCL<%d>: ERROR: sid %u EPOLL_CTL_DEL: "
-			"not a vep session!", getpid (), session_handle);
+	  VDBG (0, "EPOLL_CTL_DEL: %u not a vep session!", session_handle);
 	  rv = VPPCOM_EINVAL;
 	  goto done;
 	}
       else if (PREDICT_FALSE (session->vep.vep_sh != vep_handle))
 	{
-	  clib_warning ("VCL<%d>: ERROR: sid %u EPOLL_CTL_DEL: "
-			"vep_idx (%u) != vep_idx (%u)!",
-			getpid (), session_handle,
-			session->vep.vep_sh, vep_handle);
+	  VDBG (0, "EPOLL_CTL_DEL: sh %u vep_sh (%u) != vep_sh (%u)!",
+		session_handle, session->vep.vep_sh, vep_handle);
 	  rv = VPPCOM_EINVAL;
 	  goto done;
 	}
 
-      vep_session->wait_cont_idx =
-	(vep_session->wait_cont_idx == session_handle) ?
-	session->vep.next_sh : vep_session->wait_cont_idx;
-
       if (session->vep.prev_sh == vep_handle)
 	vep_session->vep.next_sh = session->vep.next_sh;
       else
@@ -2135,9 +2408,8 @@ vppcom_epoll_ctl (uint32_t vep_handle, int op, uint32_t session_handle,
 	  prev_session = vcl_session_get_w_handle (wrk, session->vep.prev_sh);
 	  if (PREDICT_FALSE (!prev_session))
 	    {
-	      clib_warning ("VCL<%d>: ERROR: EPOLL_CTL_DEL: Invalid "
-			    "vep.prev_sid (%u) on sid (%u)!",
-			    getpid (), session->vep.prev_sh, session_handle);
+	      VDBG (0, "EPOLL_CTL_DEL: Invalid prev_sh (%u) on sh (%u)!",
+		    session->vep.prev_sh, session_handle);
 	      return VPPCOM_EBADFD;
 	    }
 	  ASSERT (prev_session->vep.next_sh == session_handle);
@@ -2149,9 +2421,8 @@ vppcom_epoll_ctl (uint32_t vep_handle, int op, uint32_t session_handle,
 	  next_session = vcl_session_get_w_handle (wrk, session->vep.next_sh);
 	  if (PREDICT_FALSE (!next_session))
 	    {
-	      clib_warning ("VCL<%d>: ERROR: EPOLL_CTL_DEL: Invalid "
-			    "vep.next_sid (%u) on sid (%u)!",
-			    getpid (), session->vep.next_sh, session_handle);
+	      VDBG (0, "EPOLL_CTL_DEL: Invalid next_sh (%u) on sh (%u)!",
+		    session->vep.next_sh, session_handle);
 	      return VPPCOM_EBADFD;
 	    }
 	  ASSERT (next_session->vep.prev_sh == session_handle);
@@ -2163,13 +2434,17 @@ vppcom_epoll_ctl (uint32_t vep_handle, int op, uint32_t session_handle,
       session->vep.prev_sh = ~0;
       session->vep.vep_sh = ~0;
       session->is_vep_session = 0;
-      VDBG (1, "VCL<%d>: EPOLL_CTL_DEL: vep_idx %u, sid %u!",
-	    getpid (), vep_handle, session_handle);
+
+      if (session->tx_fifo)
+	svm_fifo_del_want_deq_ntf (session->tx_fifo, SVM_FIFO_NO_DEQ_NOTIF);
+
+      VDBG (1, "EPOLL_CTL_DEL: vep_idx %u, sh %u!", vep_handle,
+	    session_handle);
       vcl_evt (VCL_EVT_EPOLL_CTLDEL, session, vep_sh);
       break;
 
     default:
-      clib_warning ("VCL<%d>: ERROR: Invalid operation (%d)!", getpid (), op);
+      VDBG (0, "Invalid operation (%d)!", op);
       rv = VPPCOM_EINVAL;
     }
 
@@ -2179,23 +2454,133 @@ done:
   return rv;
 }
 
-static int
-vcl_epoll_wait_handle_mq (vcl_worker_t * wrk, svm_msg_q_t * mq,
-			  struct epoll_event *events, u32 maxevents,
-			  double wait_for_time, u32 * num_ev)
+static inline void
+vcl_epoll_wait_handle_mq_event (vcl_worker_t * wrk, session_event_t * e,
+				struct epoll_event *events, u32 * num_ev)
 {
   session_disconnected_msg_t *disconnected_msg;
   session_connected_msg_t *connected_msg;
-  session_accepted_msg_t *accepted_msg;
-  u64 session_evt_data = ~0, handle;
   u32 sid = ~0, session_events;
-  vcl_session_msg_t *vcl_msg;
+  u64 session_evt_data = ~0;
   vcl_session_t *session;
+  u8 add_event = 0;
+
+  switch (e->event_type)
+    {
+    case SESSION_IO_EVT_RX:
+      sid = e->session_index;
+      if (!(session = vcl_session_get (wrk, sid)))
+	break;
+      vcl_fifo_rx_evt_valid_or_break (session);
+      session_events = session->vep.ev.events;
+      if (!(EPOLLIN & session->vep.ev.events) || session->has_rx_evt)
+	break;
+      add_event = 1;
+      events[*num_ev].events |= EPOLLIN;
+      session_evt_data = session->vep.ev.data.u64;
+      session->has_rx_evt = 1;
+      break;
+    case SESSION_IO_EVT_TX:
+      sid = e->session_index;
+      if (!(session = vcl_session_get (wrk, sid)))
+	break;
+      session_events = session->vep.ev.events;
+      if (!(EPOLLOUT & session_events))
+	break;
+      add_event = 1;
+      events[*num_ev].events |= EPOLLOUT;
+      session_evt_data = session->vep.ev.data.u64;
+      svm_fifo_reset_has_deq_ntf (session->tx_fifo);
+      break;
+    case SESSION_CTRL_EVT_ACCEPTED:
+      session = vcl_session_accepted (wrk,
+				      (session_accepted_msg_t *) e->data);
+      if (!session)
+	break;
+
+      session_events = session->vep.ev.events;
+      if (!(EPOLLIN & session_events))
+	break;
+
+      add_event = 1;
+      events[*num_ev].events |= EPOLLIN;
+      session_evt_data = session->vep.ev.data.u64;
+      break;
+    case SESSION_CTRL_EVT_CONNECTED:
+      connected_msg = (session_connected_msg_t *) e->data;
+      vcl_session_connected_handler (wrk, connected_msg);
+      /* Generate EPOLLOUT because there's no connected event */
+      sid = vcl_session_index_from_vpp_handle (wrk, connected_msg->handle);
+      if (!(session = vcl_session_get (wrk, sid)))
+	break;
+      session_events = session->vep.ev.events;
+      if (!(EPOLLOUT & session_events))
+	break;
+      add_event = 1;
+      events[*num_ev].events |= EPOLLOUT;
+      session_evt_data = session->vep.ev.data.u64;
+      break;
+    case SESSION_CTRL_EVT_DISCONNECTED:
+      disconnected_msg = (session_disconnected_msg_t *) e->data;
+      session = vcl_session_disconnected_handler (wrk, disconnected_msg);
+      if (!session)
+	break;
+      session_events = session->vep.ev.events;
+      if (!((EPOLLHUP | EPOLLRDHUP) & session_events))
+	break;
+      add_event = 1;
+      events[*num_ev].events |= EPOLLHUP | EPOLLRDHUP;
+      session_evt_data = session->vep.ev.data.u64;
+      break;
+    case SESSION_CTRL_EVT_RESET:
+      sid = vcl_session_reset_handler (wrk, (session_reset_msg_t *) e->data);
+      if (!(session = vcl_session_get (wrk, sid)))
+	break;
+      session_events = session->vep.ev.events;
+      if (!((EPOLLHUP | EPOLLRDHUP) & session_events))
+	break;
+      add_event = 1;
+      events[*num_ev].events |= EPOLLHUP | EPOLLRDHUP;
+      session_evt_data = session->vep.ev.data.u64;
+      break;
+    case SESSION_CTRL_EVT_UNLISTEN_REPLY:
+      vcl_session_unlisten_reply_handler (wrk, e->data);
+      break;
+    case SESSION_CTRL_EVT_REQ_WORKER_UPDATE:
+      vcl_session_req_worker_update_handler (wrk, e->data);
+      break;
+    case SESSION_CTRL_EVT_WORKER_UPDATE_REPLY:
+      vcl_session_worker_update_reply_handler (wrk, e->data);
+      break;
+    default:
+      VDBG (0, "unhandled: %u", e->event_type);
+      break;
+    }
+
+  if (add_event)
+    {
+      events[*num_ev].data.u64 = session_evt_data;
+      if (EPOLLONESHOT & session_events)
+	{
+	  session = vcl_session_get (wrk, sid);
+	  session->vep.ev.events = 0;
+	}
+      *num_ev += 1;
+    }
+}
+
+static int
+vcl_epoll_wait_handle_mq (vcl_worker_t * wrk, svm_msg_q_t * mq,
+			  struct epoll_event *events, u32 maxevents,
+			  double wait_for_time, u32 * num_ev)
+{
   svm_msg_q_msg_t *msg;
   session_event_t *e;
-  u8 add_event;
   int i;
 
+  if (vec_len (wrk->mq_msg_vector) && svm_msg_q_is_empty (mq))
+    goto handle_dequeued;
+
   svm_msg_q_lock (mq);
   if (svm_msg_q_is_empty (mq))
     {
@@ -2217,183 +2602,64 @@ vcl_epoll_wait_handle_mq (vcl_worker_t * wrk, svm_msg_q_t * mq,
 	    }
 	}
     }
-  vcl_mq_dequeue_batch (wrk, mq);
+  ASSERT (maxevents > *num_ev);
+  vcl_mq_dequeue_batch (wrk, mq, maxevents - *num_ev);
   svm_msg_q_unlock (mq);
 
+handle_dequeued:
   for (i = 0; i < vec_len (wrk->mq_msg_vector); i++)
     {
       msg = vec_elt_at_index (wrk->mq_msg_vector, i);
       e = svm_msg_q_msg_data (mq, msg);
-      add_event = 0;
-      switch (e->event_type)
-	{
-	case FIFO_EVENT_APP_RX:
-	  sid = e->fifo->client_session_index;
-	  session = vcl_session_get (wrk, sid);
-	  session_events = session->vep.ev.events;
-	  if (!(EPOLLIN & session->vep.ev.events))
-	    break;
-	  add_event = 1;
-	  events[*num_ev].events |= EPOLLIN;
-	  session_evt_data = session->vep.ev.data.u64;
-	  break;
-	case FIFO_EVENT_APP_TX:
-	  sid = e->fifo->client_session_index;
-	  session = vcl_session_get (wrk, sid);
-	  session_events = session->vep.ev.events;
-	  if (!(EPOLLOUT & session_events))
-	    break;
-	  add_event = 1;
-	  events[*num_ev].events |= EPOLLOUT;
-	  session_evt_data = session->vep.ev.data.u64;
-	  break;
-	case SESSION_IO_EVT_CT_TX:
-	  session = vcl_ct_session_get_from_fifo (wrk, e->fifo, 0);
-	  sid = session->session_index;
-	  session_events = session->vep.ev.events;
-	  if (!(EPOLLIN & session->vep.ev.events))
-	    break;
-	  add_event = 1;
-	  events[*num_ev].events |= EPOLLIN;
-	  session_evt_data = session->vep.ev.data.u64;
-	  break;
-	case SESSION_IO_EVT_CT_RX:
-	  session = vcl_ct_session_get_from_fifo (wrk, e->fifo, 1);
-	  sid = session->session_index;
-	  session_events = session->vep.ev.events;
-	  if (!(EPOLLOUT & session_events))
-	    break;
-	  add_event = 1;
-	  events[*num_ev].events |= EPOLLOUT;
-	  session_evt_data = session->vep.ev.data.u64;
-	  break;
-	case SESSION_CTRL_EVT_ACCEPTED:
-	  accepted_msg = (session_accepted_msg_t *) e->data;
-	  handle = accepted_msg->listener_handle;
-	  session = vcl_session_table_lookup_listener (wrk, handle);
-	  if (!session)
-	    {
-	      clib_warning ("VCL<%d>: ERROR: couldn't find listen session:"
-			    "listener handle %llx", getpid (), handle);
-	      break;
-	    }
-
-	  clib_fifo_add2 (session->accept_evts_fifo, vcl_msg);
-	  vcl_msg->accepted_msg = *accepted_msg;
-	  session_events = session->vep.ev.events;
-	  if (!(EPOLLIN & session_events))
-	    break;
-
-	  add_event = 1;
-	  events[*num_ev].events |= EPOLLIN;
-	  session_evt_data = session->vep.ev.data.u64;
-	  break;
-	case SESSION_CTRL_EVT_CONNECTED:
-	  connected_msg = (session_connected_msg_t *) e->data;
-	  vcl_session_connected_handler (wrk, connected_msg);
-	  /* Generate EPOLLOUT because there's no connected event */
-	  sid = vcl_session_index_from_vpp_handle (wrk,
-						   connected_msg->handle);
-	  session = vcl_session_get (wrk, sid);
-	  session_events = session->vep.ev.events;
-	  if (EPOLLOUT & session_events)
-	    {
-	      add_event = 1;
-	      events[*num_ev].events |= EPOLLOUT;
-	      session_evt_data = session->vep.ev.data.u64;
-	    }
-	  break;
-	case SESSION_CTRL_EVT_DISCONNECTED:
-	  disconnected_msg = (session_disconnected_msg_t *) e->data;
-	  sid = vcl_session_index_from_vpp_handle (wrk,
-						   disconnected_msg->handle);
-	  if (!(session = vcl_session_get (wrk, sid)))
-	    break;
-	  add_event = 1;
-	  events[*num_ev].events |= EPOLLHUP | EPOLLRDHUP;
-	  session_evt_data = session->vep.ev.data.u64;
-	  session_events = session->vep.ev.events;
-	  break;
-	case SESSION_CTRL_EVT_RESET:
-	  sid = vcl_session_reset_handler (wrk,
-					   (session_reset_msg_t *) e->data);
-	  if (!(session = vcl_session_get (wrk, sid)))
-	    break;
-	  add_event = 1;
-	  events[*num_ev].events |= EPOLLHUP | EPOLLRDHUP;
-	  session_evt_data = session->vep.ev.data.u64;
-	  session_events = session->vep.ev.events;
-	  break;
-	default:
-	  VDBG (0, "unhandled: %u", e->event_type);
-	  svm_msg_q_free_msg (mq, msg);
-	  continue;
-	}
+      vcl_epoll_wait_handle_mq_event (wrk, e, events, num_ev);
       svm_msg_q_free_msg (mq, msg);
-
-      if (add_event)
-	{
-	  events[*num_ev].data.u64 = session_evt_data;
-	  if (EPOLLONESHOT & session_events)
-	    {
-	      session = vcl_session_get (wrk, sid);
-	      session->vep.ev.events = 0;
-	    }
-	  *num_ev += 1;
-	  if (*num_ev == maxevents)
-	    break;
-	}
     }
-
   vec_reset_length (wrk->mq_msg_vector);
+  vcl_handle_pending_wrk_updates (wrk);
   return *num_ev;
 }
 
 static int
 vppcom_epoll_wait_condvar (vcl_worker_t * wrk, struct epoll_event *events,
-			   int maxevents, double wait_for_time)
+			   int maxevents, u32 n_evts, double wait_for_time)
 {
-  vcl_cut_through_registration_t *cr;
-  double total_wait = 0, wait_slice;
-  u32 num_ev = 0;
-  int rv;
+  double wait = 0, start = 0, now;
 
-  wait_for_time = (wait_for_time == -1) ? (double) 10e9 : wait_for_time;
-  wait_slice = wrk->cut_through_registrations ? 10e-6 : wait_for_time;
+  if (!n_evts)
+    {
+      wait = wait_for_time;
+      start = clib_time_now (&wrk->clib_time);
+    }
 
   do
     {
-      vcl_ct_registration_lock (wrk);
-      /* *INDENT-OFF* */
-      pool_foreach (cr, wrk->cut_through_registrations, ({
-        vcl_epoll_wait_handle_mq (wrk, cr->mq, events, maxevents, 0, &num_ev);
-      }));
-      /* *INDENT-ON* */
-      vcl_ct_registration_unlock (wrk);
+      vcl_epoll_wait_handle_mq (wrk, wrk->app_event_queue, events, maxevents,
+				wait, &n_evts);
+      if (n_evts)
+	return n_evts;
+      if (wait == -1)
+	continue;
 
-      rv = vcl_epoll_wait_handle_mq (wrk, wrk->app_event_queue, events,
-				     maxevents, num_ev ? 0 : wait_slice,
-				     &num_ev);
-      if (rv)
-	total_wait += wait_slice;
-      if (num_ev)
-	return num_ev;
+      now = clib_time_now (&wrk->clib_time);
+      wait -= now - start;
+      start = now;
     }
-  while (total_wait < wait_for_time);
-  return (int) num_ev;
+  while (wait > 0);
+
+  return 0;
 }
 
 static int
 vppcom_epoll_wait_eventfd (vcl_worker_t * wrk, struct epoll_event *events,
-			   int maxevents, double wait_for_time)
+			   int maxevents, u32 n_evts, double wait_for_time)
 {
   vcl_mq_evt_conn_t *mqc;
   int __clib_unused n_read;
   int n_mq_evts, i;
-  u32 n_evts = 0;
   u64 buf;
 
   vec_validate (wrk->mq_events, pool_elts (wrk->mq_evt_conns));
+again:
   n_mq_evts = epoll_wait (wrk->mqs_epfd, wrk->mq_events,
 			  vec_len (wrk->mq_events), wait_for_time);
   for (i = 0; i < n_mq_evts; i++)
@@ -2402,6 +2668,8 @@ vppcom_epoll_wait_eventfd (vcl_worker_t * wrk, struct epoll_event *events,
       n_read = read (mqc->mq_fd, &buf, sizeof (buf));
       vcl_epoll_wait_handle_mq (wrk, mqc->mq, events, maxevents, 0, &n_evts);
     }
+  if (!n_evts && n_mq_evts > 0)
+    goto again;
 
   return (int) n_evts;
 }
@@ -2412,11 +2680,12 @@ vppcom_epoll_wait (uint32_t vep_handle, struct epoll_event *events,
 {
   vcl_worker_t *wrk = vcl_worker_get_current ();
   vcl_session_t *vep_session;
+  u32 n_evts = 0;
+  int i;
 
   if (PREDICT_FALSE (maxevents <= 0))
     {
-      clib_warning ("VCL<%d>: ERROR: Invalid maxevents (%d)!",
-		    getpid (), maxevents);
+      VDBG (0, "ERROR: Invalid maxevents (%d)!", maxevents);
       return VPPCOM_EINVAL;
     }
 
@@ -2426,17 +2695,33 @@ vppcom_epoll_wait (uint32_t vep_handle, struct epoll_event *events,
 
   if (PREDICT_FALSE (!vep_session->is_vep))
     {
-      clib_warning ("VCL<%d>: ERROR: vep_idx (%u) is not a vep!",
-		    getpid (), vep_handle);
+      VDBG (0, "ERROR: vep_idx (%u) is not a vep!", vep_handle);
       return VPPCOM_EINVAL;
     }
 
   memset (events, 0, sizeof (*events) * maxevents);
 
+  if (vec_len (wrk->unhandled_evts_vector))
+    {
+      for (i = 0; i < vec_len (wrk->unhandled_evts_vector); i++)
+	{
+	  vcl_epoll_wait_handle_mq_event (wrk, &wrk->unhandled_evts_vector[i],
+					  events, &n_evts);
+	  if (n_evts == maxevents)
+	    {
+	      vec_delete (wrk->unhandled_evts_vector, i + 1, 0);
+	      return n_evts;
+	    }
+	}
+      vec_reset_length (wrk->unhandled_evts_vector);
+    }
+
   if (vcm->cfg.use_mq_eventfd)
-    return vppcom_epoll_wait_eventfd (wrk, events, maxevents, wait_for_time);
+    return vppcom_epoll_wait_eventfd (wrk, events, maxevents, n_evts,
+				      wait_for_time);
 
-  return vppcom_epoll_wait_condvar (wrk, events, maxevents, wait_for_time);
+  return vppcom_epoll_wait_condvar (wrk, events, maxevents, n_evts,
+				    wait_for_time);
 }
 
 int
@@ -2446,7 +2731,7 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
   vcl_worker_t *wrk = vcl_worker_get_current ();
   vcl_session_t *session;
   int rv = VPPCOM_OK;
-  u32 *flags = buffer;
+  u32 *flags = buffer, tmp_flags = 0;
   vppcom_endpt_t *ep = buffer;
 
   session = vcl_session_get_w_handle (wrk, session_handle);
@@ -2456,15 +2741,15 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
   switch (op)
     {
     case VPPCOM_ATTR_GET_NREAD:
-      rv = vppcom_session_read_ready (session);
-      VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_NREAD: sid %u, nread = %d",
-	    getpid (), rv);
+      rv = vcl_session_read_ready (session);
+      VDBG (2, "VPPCOM_ATTR_GET_NREAD: sh %u, nread = %d", session_handle,
+	    rv);
       break;
 
     case VPPCOM_ATTR_GET_NWRITE:
-      rv = vppcom_session_write_ready (session);
-      VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_NWRITE: sid %u, nwrite = %d",
-	    getpid (), session_handle, rv);
+      rv = vcl_session_write_ready (session);
+      VDBG (2, "VPPCOM_ATTR_GET_NWRITE: sh %u, nwrite = %d", session_handle,
+	    rv);
       break;
 
     case VPPCOM_ATTR_GET_FLAGS:
@@ -2473,9 +2758,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  *flags = O_RDWR | (VCL_SESS_ATTR_TEST (session->attr,
 						 VCL_SESS_ATTR_NONBLOCK));
 	  *buflen = sizeof (*flags);
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_FLAGS: sid %u, flags = 0x%08x, "
-		"is_nonblocking = %u", getpid (),
-		session_handle, *flags,
+	  VDBG (2, "VPPCOM_ATTR_GET_FLAGS: sh %u, flags = 0x%08x, "
+		"is_nonblocking = %u", session_handle, *flags,
 		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_NONBLOCK));
 	}
       else
@@ -2490,9 +2774,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  else
 	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_NONBLOCK);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_SET_FLAGS: sid %u, flags = 0x%08x,"
-		" is_nonblocking = %u",
-		getpid (), session_handle, *flags,
+	  VDBG (2, "VPPCOM_ATTR_SET_FLAGS: sh %u, flags = 0x%08x,"
+		" is_nonblocking = %u", session_handle, *flags,
 		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_NONBLOCK));
 	}
       else
@@ -2506,16 +2789,15 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  ep->is_ip4 = session->transport.is_ip4;
 	  ep->port = session->transport.rmt_port;
 	  if (session->transport.is_ip4)
-	    clib_memcpy (ep->ip, &session->transport.rmt_ip.ip4,
-			 sizeof (ip4_address_t));
+	    clib_memcpy_fast (ep->ip, &session->transport.rmt_ip.ip4,
+			      sizeof (ip4_address_t));
 	  else
-	    clib_memcpy (ep->ip, &session->transport.rmt_ip.ip6,
-			 sizeof (ip6_address_t));
+	    clib_memcpy_fast (ep->ip, &session->transport.rmt_ip.ip6,
+			      sizeof (ip6_address_t));
 	  *buflen = sizeof (*ep);
-	  VDBG (1, "VCL<%d>: VPPCOM_ATTR_GET_PEER_ADDR: sid %u, is_ip4 = %u, "
-		"addr = %U, port %u", getpid (),
-		session_handle, ep->is_ip4, format_ip46_address,
-		&session->transport.rmt_ip,
+	  VDBG (1, "VPPCOM_ATTR_GET_PEER_ADDR: sh %u, is_ip4 = %u, "
+		"addr = %U, port %u", session_handle, ep->is_ip4,
+		format_ip46_address, &session->transport.rmt_ip,
 		ep->is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
 		clib_net_to_host_u16 (ep->port));
 	}
@@ -2530,15 +2812,14 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  ep->is_ip4 = session->transport.is_ip4;
 	  ep->port = session->transport.lcl_port;
 	  if (session->transport.is_ip4)
-	    clib_memcpy (ep->ip, &session->transport.lcl_ip.ip4,
-			 sizeof (ip4_address_t));
+	    clib_memcpy_fast (ep->ip, &session->transport.lcl_ip.ip4,
+			      sizeof (ip4_address_t));
 	  else
-	    clib_memcpy (ep->ip, &session->transport.lcl_ip.ip6,
-			 sizeof (ip6_address_t));
+	    clib_memcpy_fast (ep->ip, &session->transport.lcl_ip.ip6,
+			      sizeof (ip6_address_t));
 	  *buflen = sizeof (*ep);
-	  VDBG (1, "VCL<%d>: VPPCOM_ATTR_GET_LCL_ADDR: sid %u, is_ip4 = %u,"
-		" addr = %U port %d", getpid (),
-		session_handle, ep->is_ip4, format_ip46_address,
+	  VDBG (1, "VPPCOM_ATTR_GET_LCL_ADDR: sh %u, is_ip4 = %u, addr = %U"
+		" port %d", session_handle, ep->is_ip4, format_ip46_address,
 		&session->transport.lcl_ip,
 		ep->is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
 		clib_net_to_host_u16 (ep->port));
@@ -2549,8 +2830,7 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 
     case VPPCOM_ATTR_GET_LIBC_EPFD:
       rv = session->libc_epfd;
-      VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_LIBC_EPFD: libc_epfd %d",
-	    getpid (), rv);
+      VDBG (2, "VPPCOM_ATTR_GET_LIBC_EPFD: libc_epfd %d", rv);
       break;
 
     case VPPCOM_ATTR_SET_LIBC_EPFD:
@@ -2560,8 +2840,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  session->libc_epfd = *(int *) buffer;
 	  *buflen = sizeof (session->libc_epfd);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_SET_LIBC_EPFD: libc_epfd %d, "
-		"buflen %d", getpid (), session->libc_epfd, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_SET_LIBC_EPFD: libc_epfd %d, buflen %d",
+		session->libc_epfd, *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2573,9 +2853,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  *(int *) buffer = session->session_type;
 	  *buflen = sizeof (int);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_PROTOCOL: %d (%s), buflen %d",
-		getpid (), *(int *) buffer, *(int *) buffer ? "UDP" : "TCP",
-		*buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_PROTOCOL: %d (%s), buflen %d",
+		*(int *) buffer, *(int *) buffer ? "UDP" : "TCP", *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2588,8 +2867,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 						VCL_SESS_ATTR_LISTEN);
 	  *buflen = sizeof (int);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_LISTEN: %d, buflen %d",
-		getpid (), *(int *) buffer, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_LISTEN: %d, buflen %d", *(int *) buffer,
+		*buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2601,8 +2880,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  *(int *) buffer = 0;
 	  *buflen = sizeof (int);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_ERROR: %d, buflen %d, #VPP-TBD#",
-		getpid (), *(int *) buffer, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_ERROR: %d, buflen %d, #VPP-TBD#",
+		*(int *) buffer, *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2618,9 +2897,9 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 				vcm->cfg.tx_fifo_size);
 	  *buflen = sizeof (u32);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_TX_FIFO_LEN: %u (0x%x), "
-		"buflen %d, #VPP-TBD#", getpid (),
-		*(size_t *) buffer, *(size_t *) buffer, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_TX_FIFO_LEN: %u (0x%x), buflen %d,"
+		" #VPP-TBD#", *(size_t *) buffer, *(size_t *) buffer,
+		*buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2631,9 +2910,9 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	{
 	  /* VPP-TBD */
 	  session->sndbuf_size = *(u32 *) buffer;
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_SET_TX_FIFO_LEN: %u (0x%x), "
-		"buflen %d, #VPP-TBD#", getpid (),
-		session->sndbuf_size, session->sndbuf_size, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_SET_TX_FIFO_LEN: %u (0x%x), buflen %d,"
+		" #VPP-TBD#", session->sndbuf_size, session->sndbuf_size,
+		*buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2649,9 +2928,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 				vcm->cfg.rx_fifo_size);
 	  *buflen = sizeof (u32);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_RX_FIFO_LEN: %u (0x%x), "
-		"buflen %d, #VPP-TBD#", getpid (),
-		*(size_t *) buffer, *(size_t *) buffer, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_RX_FIFO_LEN: %u (0x%x), buflen %d, "
+		"#VPP-TBD#", *(size_t *) buffer, *(size_t *) buffer, *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2662,9 +2940,9 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	{
 	  /* VPP-TBD */
 	  session->rcvbuf_size = *(u32 *) buffer;
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_SET_RX_FIFO_LEN: %u (0x%x), "
-		"buflen %d, #VPP-TBD#", getpid (),
-		session->sndbuf_size, session->sndbuf_size, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_SET_RX_FIFO_LEN: %u (0x%x), buflen %d,"
+		" #VPP-TBD#", session->sndbuf_size, session->sndbuf_size,
+		*buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2678,8 +2956,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 						VCL_SESS_ATTR_REUSEADDR);
 	  *buflen = sizeof (int);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_REUSEADDR: %d, "
-		"buflen %d, #VPP-TBD#", getpid (), *(int *) buffer, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_REUSEADDR: %d, buflen %d, #VPP-TBD#",
+		*(int *) buffer, *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2695,10 +2973,9 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  else
 	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_REUSEADDR);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_SET_REUSEADDR: %d, buflen %d,"
-		" #VPP-TBD#", getpid (),
-		VCL_SESS_ATTR_TEST (session->attr,
-				    VCL_SESS_ATTR_REUSEADDR), *buflen);
+	  VDBG (2, "VPPCOM_ATTR_SET_REUSEADDR: %d, buflen %d, #VPP-TBD#",
+		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_REUSEADDR),
+		*buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2712,8 +2989,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 						VCL_SESS_ATTR_REUSEPORT);
 	  *buflen = sizeof (int);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_REUSEPORT: %d, buflen %d,"
-		" #VPP-TBD#", getpid (), *(int *) buffer, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_REUSEPORT: %d, buflen %d, #VPP-TBD#",
+		*(int *) buffer, *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2729,10 +3006,9 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  else
 	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_REUSEPORT);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_SET_REUSEPORT: %d, buflen %d,"
-		" #VPP-TBD#", getpid (),
-		VCL_SESS_ATTR_TEST (session->attr,
-				    VCL_SESS_ATTR_REUSEPORT), *buflen);
+	  VDBG (2, "VPPCOM_ATTR_SET_REUSEPORT: %d, buflen %d, #VPP-TBD#",
+		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_REUSEPORT),
+		*buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2746,8 +3022,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 						VCL_SESS_ATTR_BROADCAST);
 	  *buflen = sizeof (int);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_BROADCAST: %d, buflen %d,"
-		" #VPP-TBD#", getpid (), *(int *) buffer, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_BROADCAST: %d, buflen %d, #VPP-TBD#",
+		*(int *) buffer, *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2762,10 +3038,9 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  else
 	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_BROADCAST);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_SET_BROADCAST: %d, buflen %d, "
-		"#VPP-TBD#", getpid (),
-		VCL_SESS_ATTR_TEST (session->attr,
-				    VCL_SESS_ATTR_BROADCAST), *buflen);
+	  VDBG (2, "VPPCOM_ATTR_SET_BROADCAST: %d, buflen %d, #VPP-TBD#",
+		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_BROADCAST),
+		*buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2779,8 +3054,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 						VCL_SESS_ATTR_V6ONLY);
 	  *buflen = sizeof (int);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_V6ONLY: %d, buflen %d, "
-		"#VPP-TBD#", getpid (), *(int *) buffer, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_V6ONLY: %d, buflen %d, #VPP-TBD#",
+		*(int *) buffer, *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2795,10 +3070,9 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  else
 	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_V6ONLY);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_SET_V6ONLY: %d, buflen %d, "
-		"#VPP-TBD#", getpid (),
-		VCL_SESS_ATTR_TEST (session->attr,
-				    VCL_SESS_ATTR_V6ONLY), *buflen);
+	  VDBG (2, "VPPCOM_ATTR_SET_V6ONLY: %d, buflen %d, #VPP-TBD#",
+		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_V6ONLY),
+		*buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2812,8 +3086,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 						VCL_SESS_ATTR_KEEPALIVE);
 	  *buflen = sizeof (int);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_KEEPALIVE: %d, buflen %d, "
-		"#VPP-TBD#", getpid (), *(int *) buffer, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_KEEPALIVE: %d, buflen %d, #VPP-TBD#",
+		*(int *) buffer, *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2828,10 +3102,9 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  else
 	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_KEEPALIVE);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_SET_KEEPALIVE: %d, buflen %d, "
-		"#VPP-TBD#", getpid (),
-		VCL_SESS_ATTR_TEST (session->attr,
-				    VCL_SESS_ATTR_KEEPALIVE), *buflen);
+	  VDBG (2, "VPPCOM_ATTR_SET_KEEPALIVE: %d, buflen %d, #VPP-TBD#",
+		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_KEEPALIVE),
+		*buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2845,8 +3118,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 						VCL_SESS_ATTR_TCP_NODELAY);
 	  *buflen = sizeof (int);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_TCP_NODELAY: %d, buflen %d, "
-		"#VPP-TBD#", getpid (), *(int *) buffer, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_TCP_NODELAY: %d, buflen %d, #VPP-TBD#",
+		*(int *) buffer, *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2861,10 +3134,9 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  else
 	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_TCP_NODELAY);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_SET_TCP_NODELAY: %d, buflen %d, "
-		"#VPP-TBD#", getpid (),
-		VCL_SESS_ATTR_TEST (session->attr,
-				    VCL_SESS_ATTR_TCP_NODELAY), *buflen);
+	  VDBG (2, "VPPCOM_ATTR_SET_TCP_NODELAY: %d, buflen %d, #VPP-TBD#",
+		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_TCP_NODELAY),
+		*buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2878,8 +3150,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 						VCL_SESS_ATTR_TCP_KEEPIDLE);
 	  *buflen = sizeof (int);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_TCP_KEEPIDLE: %d, buflen %d, "
-		"#VPP-TBD#", getpid (), *(int *) buffer, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_TCP_KEEPIDLE: %d, buflen %d, #VPP-TBD#",
+		*(int *) buffer, *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2894,8 +3166,7 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  else
 	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_TCP_KEEPIDLE);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_SET_TCP_KEEPIDLE: %d, buflen %d, "
-		"#VPP-TBD#", getpid (),
+	  VDBG (2, "VPPCOM_ATTR_SET_TCP_KEEPIDLE: %d, buflen %d, #VPP-TBD#",
 		VCL_SESS_ATTR_TEST (session->attr,
 				    VCL_SESS_ATTR_TCP_KEEPIDLE), *buflen);
 	}
@@ -2911,8 +3182,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 						VCL_SESS_ATTR_TCP_KEEPINTVL);
 	  *buflen = sizeof (int);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_TCP_KEEPINTVL: %d, buflen %d, "
-		"#VPP-TBD#", getpid (), *(int *) buffer, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_TCP_KEEPINTVL: %d, buflen %d, #VPP-TBD#",
+		*(int *) buffer, *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2927,8 +3198,7 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  else
 	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_TCP_KEEPINTVL);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_SET_TCP_KEEPINTVL: %d, buflen %d, "
-		"#VPP-TBD#", getpid (),
+	  VDBG (2, "VPPCOM_ATTR_SET_TCP_KEEPINTVL: %d, buflen %d, #VPP-TBD#",
 		VCL_SESS_ATTR_TEST (session->attr,
 				    VCL_SESS_ATTR_TCP_KEEPINTVL), *buflen);
 	}
@@ -2943,8 +3213,8 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  *(u32 *) buffer = session->user_mss;
 	  *buflen = sizeof (int);
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_GET_TCP_USER_MSS: %d, buflen %d,"
-		" #VPP-TBD#", getpid (), *(int *) buffer, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_GET_TCP_USER_MSS: %d, buflen %d, #VPP-TBD#",
+		*(int *) buffer, *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
@@ -2956,13 +3226,33 @@ vppcom_session_attr (uint32_t session_handle, uint32_t op,
 	  /* VPP-TBD */
 	  session->user_mss = *(u32 *) buffer;
 
-	  VDBG (2, "VCL<%d>: VPPCOM_ATTR_SET_TCP_USER_MSS: %u, buflen %d, "
-		"#VPP-TBD#", getpid (), session->user_mss, *buflen);
+	  VDBG (2, "VPPCOM_ATTR_SET_TCP_USER_MSS: %u, buflen %d, #VPP-TBD#",
+		session->user_mss, *buflen);
 	}
       else
 	rv = VPPCOM_EINVAL;
       break;
 
+    case VPPCOM_ATTR_SET_SHUT:
+      if (*flags == SHUT_RD || *flags == SHUT_RDWR)
+	VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_SHUT_RD);
+      if (*flags == SHUT_WR || *flags == SHUT_RDWR)
+	VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_SHUT_WR);
+      break;
+
+    case VPPCOM_ATTR_GET_SHUT:
+      if (VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_SHUT_RD))
+	tmp_flags = 1;
+      if (VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_SHUT_WR))
+	tmp_flags |= 2;
+      if (tmp_flags == 1)
+	*(int *) buffer = SHUT_RD;
+      else if (tmp_flags == 2)
+	*(int *) buffer = SHUT_WR;
+      else if (tmp_flags == 3)
+	*(int *) buffer = SHUT_RDWR;
+      *buflen = sizeof (int);
+      break;
     default:
       rv = VPPCOM_EINVAL;
       break;
@@ -2984,8 +3274,7 @@ vppcom_session_recvfrom (uint32_t session_handle, void *buffer,
       session = vcl_session_get_w_handle (wrk, session_handle);
       if (PREDICT_FALSE (!session))
 	{
-	  VDBG (0, "VCL<%d>: invalid session, sid (%u) has been closed!",
-		getpid (), session_handle);
+	  VDBG (0, "sh 0x%llx is closed!", session_handle);
 	  return VPPCOM_EBADFD;
 	}
       ep->is_ip4 = session->transport.is_ip4;
@@ -2998,19 +3287,18 @@ vppcom_session_recvfrom (uint32_t session_handle, void *buffer,
     rv = vppcom_session_peek (session_handle, buffer, buflen);
   else
     {
-      clib_warning ("VCL<%d>: Unsupport flags for recvfrom %d",
-		    getpid (), flags);
+      VDBG (0, "Unsupport flags for recvfrom %d", flags);
       return VPPCOM_EAFNOSUPPORT;
     }
 
   if (ep)
     {
       if (session->transport.is_ip4)
-	clib_memcpy (ep->ip, &session->transport.rmt_ip.ip4,
-		     sizeof (ip4_address_t));
+	clib_memcpy_fast (ep->ip, &session->transport.rmt_ip.ip4,
+			  sizeof (ip4_address_t));
       else
-	clib_memcpy (ep->ip, &session->transport.rmt_ip.ip6,
-		     sizeof (ip6_address_t));
+	clib_memcpy_fast (ep->ip, &session->transport.rmt_ip.ip6,
+			  sizeof (ip6_address_t));
     }
 
   return rv;
@@ -3032,11 +3320,10 @@ vppcom_session_sendto (uint32_t session_handle, void *buffer,
   if (flags)
     {
       // TBD check the flags and do the right thing
-      VDBG (2, "VCL<%d>: handling flags 0x%u (%d) not implemented yet.",
-	    getpid (), flags, flags);
+      VDBG (2, "handling flags 0x%u (%d) not implemented yet.", flags, flags);
     }
 
-  return (vppcom_session_write (session_handle, buffer, buflen));
+  return (vppcom_session_write_inline (session_handle, buffer, buflen, 1));
 }
 
 int
@@ -3045,10 +3332,11 @@ vppcom_poll (vcl_poll_t * vp, uint32_t n_sids, double wait_for_time)
   vcl_worker_t *wrk = vcl_worker_get_current ();
   f64 timeout = clib_time_now (&wrk->clib_time) + wait_for_time;
   u32 i, keep_trying = 1;
+  svm_msg_q_msg_t msg;
+  session_event_t *e;
   int rv, num_ev = 0;
 
-  VDBG (3, "VCL<%d>: vp %p, nsids %u, wait_for_time %f",
-	getpid (), vp, n_sids, wait_for_time);
+  VDBG (3, "vp %p, nsids %u, wait_for_time %f", vp, n_sids, wait_for_time);
 
   if (!vp)
     return VPPCOM_EFAULT;
@@ -3057,23 +3345,33 @@ vppcom_poll (vcl_poll_t * vp, uint32_t n_sids, double wait_for_time)
     {
       vcl_session_t *session;
 
-      for (i = 0; i < n_sids; i++)
+      /* Dequeue all events and drop all unhandled io events */
+      while (svm_msg_q_sub (wrk->app_event_queue, &msg, SVM_Q_NOWAIT, 0) == 0)
 	{
-	  ASSERT (vp[i].revents);
+	  e = svm_msg_q_msg_data (wrk->app_event_queue, &msg);
+	  vcl_handle_mq_event (wrk, e);
+	  svm_msg_q_free_msg (wrk->app_event_queue, &msg);
+	}
+      vec_reset_length (wrk->unhandled_evts_vector);
 
-	  session = vcl_session_get (wrk, vp[i].sid);
+      for (i = 0; i < n_sids; i++)
+	{
+	  session = vcl_session_get (wrk, vp[i].sh);
 	  if (!session)
-	    continue;
+	    {
+	      vp[i].revents = POLLHUP;
+	      num_ev++;
+	      continue;
+	    }
 
-	  if (*vp[i].revents)
-	    *vp[i].revents = 0;
+	  vp[i].revents = 0;
 
 	  if (POLLIN & vp[i].events)
 	    {
-	      rv = vppcom_session_read_ready (session);
+	      rv = vcl_session_read_ready (session);
 	      if (rv > 0)
 		{
-		  *vp[i].revents |= POLLIN;
+		  vp[i].revents |= POLLIN;
 		  num_ev++;
 		}
 	      else if (rv < 0)
@@ -3081,11 +3379,11 @@ vppcom_poll (vcl_poll_t * vp, uint32_t n_sids, double wait_for_time)
 		  switch (rv)
 		    {
 		    case VPPCOM_ECONNRESET:
-		      *vp[i].revents = POLLHUP;
+		      vp[i].revents = POLLHUP;
 		      break;
 
 		    default:
-		      *vp[i].revents = POLLERR;
+		      vp[i].revents = POLLERR;
 		      break;
 		    }
 		  num_ev++;
@@ -3094,10 +3392,10 @@ vppcom_poll (vcl_poll_t * vp, uint32_t n_sids, double wait_for_time)
 
 	  if (POLLOUT & vp[i].events)
 	    {
-	      rv = vppcom_session_write_ready (session);
+	      rv = vcl_session_write_ready (session);
 	      if (rv > 0)
 		{
-		  *vp[i].revents |= POLLOUT;
+		  vp[i].revents |= POLLOUT;
 		  num_ev++;
 		}
 	      else if (rv < 0)
@@ -3105,11 +3403,11 @@ vppcom_poll (vcl_poll_t * vp, uint32_t n_sids, double wait_for_time)
 		  switch (rv)
 		    {
 		    case VPPCOM_ECONNRESET:
-		      *vp[i].revents = POLLHUP;
+		      vp[i].revents = POLLHUP;
 		      break;
 
 		    default:
-		      *vp[i].revents = POLLERR;
+		      vp[i].revents = POLLERR;
 		      break;
 		    }
 		  num_ev++;
@@ -3118,7 +3416,7 @@ vppcom_poll (vcl_poll_t * vp, uint32_t n_sids, double wait_for_time)
 
 	  if (0)		// Note "done:" label used by VCL_SESSION_LOCK_AND_GET()
 	    {
-	      *vp[i].revents = POLLNVAL;
+	      vp[i].revents = POLLNVAL;
 	      num_ev++;
 	    }
 	}
@@ -3127,16 +3425,6 @@ vppcom_poll (vcl_poll_t * vp, uint32_t n_sids, double wait_for_time)
     }
   while ((num_ev == 0) && keep_trying);
 
-  if (VPPCOM_DEBUG > 3)
-    {
-      clib_warning ("VCL<%d>: returning %d", getpid (), num_ev);
-      for (i = 0; i < n_sids; i++)
-	{
-	  clib_warning ("VCL<%d>: vp[%d].sid %d (0x%x), .events 0x%x, "
-			".revents 0x%x", getpid (), i, vp[i].sid, vp[i].sid,
-			vp[i].events, *vp[i].revents);
-	}
-    }
   return num_ev;
 }
 
@@ -3148,17 +3436,89 @@ vppcom_mq_epoll_fd (void)
 }
 
 int
-vppcom_session_index (uint32_t session_handle)
+vppcom_session_index (vcl_session_handle_t session_handle)
 {
   return session_handle & 0xFFFFFF;
 }
 
+int
+vppcom_session_worker (vcl_session_handle_t session_handle)
+{
+  return session_handle >> 24;
+}
+
 int
 vppcom_worker_register (void)
 {
   if (!vcl_worker_alloc_and_init ())
-    return VPPCOM_OK;
-  return VPPCOM_EEXIST;
+    return VPPCOM_EEXIST;
+
+  if (vcl_worker_set_bapi ())
+    return VPPCOM_EEXIST;
+
+  if (vcl_worker_register_with_vpp ())
+    return VPPCOM_EEXIST;
+
+  return VPPCOM_OK;
+}
+
+void
+vppcom_worker_unregister (void)
+{
+  vcl_worker_cleanup (vcl_worker_get_current (), 1 /* notify vpp */ );
+  vcl_set_worker_index (~0);
+}
+
+int
+vppcom_worker_index (void)
+{
+  return vcl_get_worker_index ();
+}
+
+int
+vppcom_worker_mqs_epfd (void)
+{
+  vcl_worker_t *wrk = vcl_worker_get_current ();
+  if (!vcm->cfg.use_mq_eventfd)
+    return -1;
+  return wrk->mqs_epfd;
+}
+
+int
+vppcom_session_is_connectable_listener (uint32_t session_handle)
+{
+  vcl_session_t *session;
+  vcl_worker_t *wrk = vcl_worker_get_current ();
+  session = vcl_session_get_w_handle (wrk, session_handle);
+  if (!session)
+    return VPPCOM_EBADFD;
+  return vcl_session_is_connectable_listener (wrk, session);
+}
+
+int
+vppcom_session_listener (uint32_t session_handle)
+{
+  vcl_worker_t *wrk = vcl_worker_get_current ();
+  vcl_session_t *listen_session, *session;
+  session = vcl_session_get_w_handle (wrk, session_handle);
+  if (!session)
+    return VPPCOM_EBADFD;
+  if (session->listener_index == VCL_INVALID_SESSION_INDEX)
+    return VPPCOM_EBADFD;
+  listen_session = vcl_session_get_w_handle (wrk, session->listener_index);
+  if (!listen_session)
+    return VPPCOM_EBADFD;
+  return vcl_session_handle (listen_session);
+}
+
+int
+vppcom_session_n_accepted (uint32_t session_handle)
+{
+  vcl_worker_t *wrk = vcl_worker_get_current ();
+  vcl_session_t *session = vcl_session_get_w_handle (wrk, session_handle);
+  if (!session)
+    return VPPCOM_EBADFD;
+  return session->n_accepted_sessions;
 }
 
 /*