session tcp vcl: api to update connection attributes
[vpp.git] / src / vnet / session / session_node.c
index 2a4bb6b..22ab3e8 100644 (file)
@@ -24,6 +24,7 @@
 #include <vnet/session/application_local.h>
 #include <vnet/session/session_debug.h>
 #include <svm/queue.h>
+#include <sys/timerfd.h>
 
 #define app_check_thread_and_barrier(_fn, _arg)                                \
   if (!vlib_thread_is_main_w_barrier ())                               \
@@ -49,7 +50,7 @@ session_mq_listen_handler (void *data)
 
   clib_memset (a, 0, sizeof (*a));
   a->sep.is_ip4 = mp->is_ip4;
-  clib_memcpy_fast (&a->sep.ip, &mp->ip, sizeof (mp->ip));
+  ip_copy (&a->sep.ip, &mp->ip, mp->is_ip4);
   a->sep.port = mp->port;
   a->sep.fib_index = mp->vrf;
   a->sep.sw_if_index = ENDPOINT_INVALID_INDEX;
@@ -58,9 +59,10 @@ session_mq_listen_handler (void *data)
   a->sep_ext.crypto_engine = mp->crypto_engine;
   a->app_index = app->app_index;
   a->wrk_map_index = mp->wrk_index;
+  a->sep_ext.transport_flags = mp->flags;
 
   if ((rv = vnet_listen (a)))
-    clib_warning ("listen returned: %d", rv);
+    clib_warning ("listen returned: %U", format_session_error, rv);
 
   app_wrk = application_get_worker (app, mp->wrk_index);
   mq_send_session_bound_cb (app_wrk->wrk_index, mp->context, a->handle, rv);
@@ -113,11 +115,17 @@ session_mq_connect_handler (void *data)
   a->sep.transport_proto = mp->proto;
   a->sep.peer.fib_index = mp->vrf;
   clib_memcpy_fast (&a->sep.peer.ip, &mp->lcl_ip, sizeof (mp->lcl_ip));
+  if (mp->is_ip4)
+    {
+      ip46_address_mask_ip4 (&a->sep.ip);
+      ip46_address_mask_ip4 (&a->sep.peer.ip);
+    }
+  a->sep.peer.port = mp->lcl_port;
   a->sep.peer.sw_if_index = ENDPOINT_INVALID_INDEX;
   a->sep_ext.parent_handle = mp->parent_handle;
   a->sep_ext.ckpair_index = mp->ckpair_index;
   a->sep_ext.crypto_engine = mp->crypto_engine;
-  a->sep_ext.flags = mp->flags;
+  a->sep_ext.transport_flags = mp->flags;
   if (mp->hostname_len)
     {
       vec_validate (a->sep_ext.hostname, mp->hostname_len - 1);
@@ -129,10 +137,9 @@ session_mq_connect_handler (void *data)
 
   if ((rv = vnet_connect (a)))
     {
-      clib_warning ("connect returned: %U", format_vnet_api_errno, rv);
+      clib_warning ("connect returned: %U", format_session_error, rv);
       app_wrk = application_get_worker (app, mp->wrk_index);
-      mq_send_session_connected_cb (app_wrk->wrk_index, mp->context, 0,
-                                   /* is_fail */ 1);
+      mq_send_session_connected_cb (app_wrk->wrk_index, mp->context, 0, rv);
     }
 
   vec_free (a->sep_ext.hostname);
@@ -161,8 +168,7 @@ session_mq_connect_uri_handler (void *data)
     {
       clib_warning ("connect_uri returned: %d", rv);
       app_wrk = application_get_worker (app, 0 /* default wrk only */ );
-      mq_send_session_connected_cb (app_wrk->wrk_index, mp->context, 0,
-                                   /* is_fail */ 1);
+      mq_send_session_connected_cb (app_wrk->wrk_index, mp->context, 0, rv);
     }
 }
 
@@ -467,8 +473,10 @@ session_mq_worker_update_handler (void *data)
   evt->event_type = SESSION_CTRL_EVT_WORKER_UPDATE_REPLY;
   rmp = (session_worker_update_reply_msg_t *) evt->data;
   rmp->handle = mp->handle;
-  rmp->rx_fifo = pointer_to_uword (s->rx_fifo);
-  rmp->tx_fifo = pointer_to_uword (s->tx_fifo);
+  if (s->rx_fifo)
+    rmp->rx_fifo = fifo_segment_fifo_offset (s->rx_fifo);
+  if (s->tx_fifo)
+    rmp->tx_fifo = fifo_segment_fifo_offset (s->tx_fifo);
   rmp->segment_handle = session_segment_handle (s);
   svm_msg_q_add_and_unlock (app_wrk->event_queue, msg);
 
@@ -485,6 +493,78 @@ session_mq_worker_update_handler (void *data)
     app_worker_close_notify (app_wrk, s);
 }
 
+static void
+session_mq_app_wrk_rpc_handler (void *data)
+{
+  session_app_wrk_rpc_msg_t *mp = (session_app_wrk_rpc_msg_t *) data;
+  svm_msg_q_msg_t _msg, *msg = &_msg;
+  session_app_wrk_rpc_msg_t *rmp;
+  app_worker_t *app_wrk;
+  session_event_t *evt;
+  application_t *app;
+
+  app = application_lookup (mp->client_index);
+  if (!app)
+    return;
+
+  app_wrk = application_get_worker (app, mp->wrk_index);
+
+  svm_msg_q_lock_and_alloc_msg_w_ring (app_wrk->event_queue,
+                                      SESSION_MQ_CTRL_EVT_RING, SVM_Q_WAIT,
+                                      msg);
+  evt = svm_msg_q_msg_data (app_wrk->event_queue, msg);
+  clib_memset (evt, 0, sizeof (*evt));
+  evt->event_type = SESSION_CTRL_EVT_APP_WRK_RPC;
+  rmp = (session_app_wrk_rpc_msg_t *) evt->data;
+  clib_memcpy (rmp->data, mp->data, sizeof (mp->data));
+  svm_msg_q_add_and_unlock (app_wrk->event_queue, msg);
+}
+
+static void
+session_mq_transport_attr_handler (void *data)
+{
+  session_transport_attr_msg_t *mp = (session_transport_attr_msg_t *) data;
+  session_transport_attr_reply_msg_t *rmp;
+  svm_msg_q_msg_t _msg, *msg = &_msg;
+  app_worker_t *app_wrk;
+  session_event_t *evt;
+  application_t *app;
+  session_t *s;
+  int rv;
+
+  app = application_lookup (mp->client_index);
+  if (!app)
+    return;
+
+  if (!(s = session_get_from_handle_if_valid (mp->handle)))
+    {
+      clib_warning ("invalid handle %llu", mp->handle);
+      return;
+    }
+  app_wrk = app_worker_get (s->app_wrk_index);
+  if (app_wrk->app_index != app->app_index)
+    {
+      clib_warning ("app %u does not own session %llu", app->app_index,
+                   mp->handle);
+      return;
+    }
+
+  rv = session_transport_attribute (s, mp->is_get, &mp->attr);
+
+  svm_msg_q_lock_and_alloc_msg_w_ring (
+    app_wrk->event_queue, SESSION_MQ_CTRL_EVT_RING, SVM_Q_WAIT, msg);
+  evt = svm_msg_q_msg_data (app_wrk->event_queue, msg);
+  clib_memset (evt, 0, sizeof (*evt));
+  evt->event_type = SESSION_CTRL_EVT_TRANSPORT_ATTR_REPLY;
+  rmp = (session_transport_attr_reply_msg_t *) evt->data;
+  rmp->handle = mp->handle;
+  rmp->retval = rv;
+  rmp->is_get = mp->is_get;
+  if (!rv && mp->is_get)
+    rmp->attr = mp->attr;
+  svm_msg_q_add_and_unlock (app_wrk->event_queue, msg);
+}
+
 vlib_node_registration_t session_queue_node;
 
 typedef struct
@@ -537,19 +617,23 @@ session_tx_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
                        u32 next_index, u32 * to_next, u16 n_segs,
                        session_t * s, u32 n_trace)
 {
-  session_queue_trace_t *t;
-  vlib_buffer_t *b;
-  int i;
-
-  for (i = 0; i < clib_min (n_trace, n_segs); i++)
+  while (n_trace && n_segs)
     {
-      b = vlib_get_buffer (vm, to_next[i]);
-      vlib_trace_buffer (vm, node, next_index, b, 1 /* follow_chain */ );
-      t = vlib_add_trace (vm, node, b, sizeof (*t));
-      t->session_index = s->session_index;
-      t->server_thread_index = s->thread_index;
+      vlib_buffer_t *b = vlib_get_buffer (vm, to_next[0]);
+      if (PREDICT_TRUE
+         (vlib_trace_buffer
+          (vm, node, next_index, b, 1 /* follow_chain */ )))
+       {
+         session_queue_trace_t *t =
+           vlib_add_trace (vm, node, b, sizeof (*t));
+         t->session_index = s->session_index;
+         t->server_thread_index = s->thread_index;
+         n_trace--;
+       }
+      to_next++;
+      n_segs--;
     }
-  vlib_set_trace_count (vm, node, n_trace - i);
+  vlib_set_trace_count (vm, node, n_trace);
 }
 
 always_inline void
@@ -594,18 +678,26 @@ session_tx_fifo_chain_tail (vlib_main_t * vm, session_tx_context_t * ctx,
              svm_fifo_t *f = ctx->s->tx_fifo;
              session_dgram_hdr_t *hdr = &ctx->hdr;
              u16 deq_now;
+             u32 offset;
+
              deq_now = clib_min (hdr->data_length - hdr->data_offset,
                                  len_to_deq);
-             n_bytes_read = svm_fifo_peek (f, hdr->data_offset, deq_now,
-                                           data);
+             offset = hdr->data_offset + SESSION_CONN_HDR_LEN;
+             n_bytes_read = svm_fifo_peek (f, offset, deq_now, data);
              ASSERT (n_bytes_read > 0);
 
              hdr->data_offset += n_bytes_read;
              if (hdr->data_offset == hdr->data_length)
                {
-                 u32 offset = hdr->data_length + SESSION_CONN_HDR_LEN;
+                 offset = hdr->data_length + SESSION_CONN_HDR_LEN;
                  svm_fifo_dequeue_drop (f, offset);
+                 if (ctx->left_to_snd > n_bytes_read)
+                   svm_fifo_peek (ctx->s->tx_fifo, 0, sizeof (ctx->hdr),
+                                  (u8 *) & ctx->hdr);
                }
+             else if (ctx->left_to_snd == n_bytes_read)
+               svm_fifo_overwrite_head (ctx->s->tx_fifo, (u8 *) & ctx->hdr,
+                                        sizeof (session_dgram_pre_hdr_t));
            }
          else
            n_bytes_read = svm_fifo_dequeue (ctx->s->tx_fifo,
@@ -684,7 +776,13 @@ session_tx_fill_buffer (vlib_main_t * vm, session_tx_context_t * ctx,
            {
              offset = hdr->data_length + SESSION_CONN_HDR_LEN;
              svm_fifo_dequeue_drop (f, offset);
+             if (ctx->left_to_snd > n_bytes_read)
+               svm_fifo_peek (ctx->s->tx_fifo, 0, sizeof (ctx->hdr),
+                              (u8 *) & ctx->hdr);
            }
+         else if (ctx->left_to_snd == n_bytes_read)
+           svm_fifo_overwrite_head (ctx->s->tx_fifo, (u8 *) & ctx->hdr,
+                                    sizeof (session_dgram_pre_hdr_t));
        }
       else
        {
@@ -752,7 +850,10 @@ session_tx_set_dequeue_params (vlib_main_t * vm, session_tx_context_t * ctx,
                               u32 max_segs, u8 peek_data)
 {
   u32 n_bytes_per_buf, n_bytes_per_seg;
+
+  n_bytes_per_buf = vlib_buffer_get_default_data_size (vm);
   ctx->max_dequeue = svm_fifo_max_dequeue_cons (ctx->s->tx_fifo);
+
   if (peek_data)
     {
       /* Offset in rx fifo from where to peek data */
@@ -767,15 +868,49 @@ session_tx_set_dequeue_params (vlib_main_t * vm, session_tx_context_t * ctx,
     {
       if (ctx->transport_vft->transport_options.tx_type == TRANSPORT_TX_DGRAM)
        {
+         u32 len, chain_limit;
+
          if (ctx->max_dequeue <= sizeof (ctx->hdr))
            {
              ctx->max_len_to_snd = 0;
              return;
            }
+
          svm_fifo_peek (ctx->s->tx_fifo, 0, sizeof (ctx->hdr),
                         (u8 *) & ctx->hdr);
          ASSERT (ctx->hdr.data_length > ctx->hdr.data_offset);
-         ctx->max_dequeue = ctx->hdr.data_length - ctx->hdr.data_offset;
+         len = ctx->hdr.data_length - ctx->hdr.data_offset;
+
+         /* Process multiple dgrams if smaller than min (buf_space, mss).
+          * This avoids handling multiple dgrams if they require buffer
+          * chains */
+         chain_limit = clib_min (n_bytes_per_buf - TRANSPORT_MAX_HDRS_LEN,
+                                 ctx->sp.snd_mss);
+         if (ctx->hdr.data_length <= chain_limit)
+           {
+             u32 first_dgram_len, dgram_len, offset, max_offset;
+             session_dgram_hdr_t hdr;
+
+             ctx->sp.snd_mss = clib_min (ctx->sp.snd_mss, len);
+             offset = ctx->hdr.data_length + sizeof (session_dgram_hdr_t);
+             first_dgram_len = len;
+             max_offset = clib_min (ctx->max_dequeue, 16 << 10);
+
+             while (offset < max_offset)
+               {
+                 svm_fifo_peek (ctx->s->tx_fifo, offset, sizeof (ctx->hdr),
+                                (u8 *) & hdr);
+                 ASSERT (hdr.data_length > hdr.data_offset);
+                 dgram_len = hdr.data_length - hdr.data_offset;
+                 if (len + dgram_len > ctx->max_dequeue
+                     || first_dgram_len != dgram_len)
+                   break;
+                 len += dgram_len;
+                 offset += sizeof (hdr) + hdr.data_length;
+               }
+           }
+
+         ctx->max_dequeue = len;
        }
     }
   ASSERT (ctx->max_dequeue > 0);
@@ -803,10 +938,26 @@ session_tx_set_dequeue_params (vlib_main_t * vm, session_tx_context_t * ctx,
       ctx->max_len_to_snd = max_segs * ctx->sp.snd_mss;
     }
 
-  n_bytes_per_buf = vlib_buffer_get_default_data_size (vm);
   ASSERT (n_bytes_per_buf > TRANSPORT_MAX_HDRS_LEN);
-  n_bytes_per_seg = TRANSPORT_MAX_HDRS_LEN + ctx->sp.snd_mss;
-  ctx->n_bufs_per_seg = ceil ((f64) n_bytes_per_seg / n_bytes_per_buf);
+  if (ctx->n_segs_per_evt > 1)
+    {
+      u32 n_bytes_last_seg, n_bufs_last_seg;
+
+      n_bytes_per_seg = TRANSPORT_MAX_HDRS_LEN + ctx->sp.snd_mss;
+      n_bytes_last_seg = TRANSPORT_MAX_HDRS_LEN + ctx->max_len_to_snd
+       - ((ctx->n_segs_per_evt - 1) * ctx->sp.snd_mss);
+      ctx->n_bufs_per_seg = ceil ((f64) n_bytes_per_seg / n_bytes_per_buf);
+      n_bufs_last_seg = ceil ((f64) n_bytes_last_seg / n_bytes_per_buf);
+      ctx->n_bufs_needed = ((ctx->n_segs_per_evt - 1) * ctx->n_bufs_per_seg)
+       + n_bufs_last_seg;
+    }
+  else
+    {
+      n_bytes_per_seg = TRANSPORT_MAX_HDRS_LEN + ctx->max_len_to_snd;
+      ctx->n_bufs_per_seg = ceil ((f64) n_bytes_per_seg / n_bytes_per_buf);
+      ctx->n_bufs_needed = ctx->n_bufs_per_seg;
+    }
+
   ctx->deq_per_buf = clib_min (ctx->sp.snd_mss, n_bytes_per_buf);
   ctx->deq_per_first_buf = clib_min (ctx->sp.snd_mss,
                                     n_bytes_per_buf -
@@ -832,7 +983,7 @@ session_tx_fifo_read_and_snd_i (session_worker_t * wrk,
                                session_evt_elt_t * elt,
                                int *n_tx_packets, u8 peek_data)
 {
-  u32 n_trace, n_bufs_needed = 0, n_left, pbi, next_index, max_burst;
+  u32 n_trace, n_left, pbi, next_index, max_burst;
   session_tx_context_t *ctx = &wrk->ctx;
   session_main_t *smm = &session_main;
   session_event_t *e = &elt->evt;
@@ -849,7 +1000,7 @@ session_tx_fifo_read_and_snd_i (session_worker_t * wrk,
     }
 
   next_index = smm->session_type_to_next[ctx->s->session_type];
-  max_burst = VLIB_FRAME_SIZE - *n_tx_packets;
+  max_burst = SESSION_NODE_FRAME_SIZE - *n_tx_packets;
 
   tp = session_get_transport_proto (ctx->s);
   ctx->transport_vft = transport_protocol_get_vft (tp);
@@ -866,7 +1017,8 @@ session_tx_fifo_read_and_snd_i (session_worker_t * wrk,
     {
       u32 n_custom_tx;
       ctx->s->flags &= ~SESSION_F_CUSTOM_TX;
-      n_custom_tx = ctx->transport_vft->custom_tx (ctx->tc, max_burst);
+      ctx->sp.max_burst_size = max_burst;
+      n_custom_tx = ctx->transport_vft->custom_tx (ctx->tc, &ctx->sp);
       *n_tx_packets += n_custom_tx;
       if (PREDICT_FALSE
          (ctx->s->session_state >= SESSION_STATE_TRANSPORT_CLOSED))
@@ -922,11 +1074,10 @@ session_tx_fifo_read_and_snd_i (session_worker_t * wrk,
       return SESSION_TX_NO_DATA;
     }
 
-  n_bufs_needed = ctx->n_segs_per_evt * ctx->n_bufs_per_seg;
-  vec_validate_aligned (wrk->tx_buffers, n_bufs_needed - 1,
+  vec_validate_aligned (wrk->tx_buffers, ctx->n_bufs_needed - 1,
                        CLIB_CACHE_LINE_BYTES);
-  n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_needed);
-  if (PREDICT_FALSE (n_bufs < n_bufs_needed))
+  n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, ctx->n_bufs_needed);
+  if (PREDICT_FALSE (n_bufs < ctx->n_bufs_needed))
     {
       if (n_bufs)
        vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
@@ -936,6 +1087,9 @@ session_tx_fifo_read_and_snd_i (session_worker_t * wrk,
       return SESSION_TX_NO_BUFFERS;
     }
 
+  if (transport_connection_is_tx_paced (ctx->tc))
+    transport_connection_tx_pacer_update_bytes (ctx->tc, ctx->max_len_to_snd);
+
   ctx->left_to_snd = ctx->max_len_to_snd;
   n_left = ctx->n_segs_per_evt;
 
@@ -1009,7 +1163,6 @@ session_tx_fifo_read_and_snd_i (session_worker_t * wrk,
     vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
 
   *n_tx_packets += ctx->n_segs_per_evt;
-  transport_connection_update_tx_bytes (ctx->tc, ctx->max_len_to_snd);
 
   SESSION_EVT (SESSION_EVT_DEQ, ctx->s, ctx->max_len_to_snd, ctx->max_dequeue,
               ctx->s->tx_fifo->has_event, wrk->last_vlib_time);
@@ -1023,19 +1176,12 @@ session_tx_fifo_read_and_snd_i (session_worker_t * wrk,
   else
     session_tx_maybe_reschedule (wrk, ctx, elt);
 
-  if (!peek_data
-      && ctx->transport_vft->transport_options.tx_type == TRANSPORT_TX_DGRAM)
+  if (!peek_data)
     {
-      /* Fix dgram pre header */
-      if (ctx->max_len_to_snd < ctx->max_dequeue)
-       svm_fifo_overwrite_head (ctx->s->tx_fifo, (u8 *) & ctx->hdr,
-                                sizeof (session_dgram_pre_hdr_t));
-      /* More data needs to be read */
-      else if (svm_fifo_max_dequeue_cons (ctx->s->tx_fifo) > 0)
-       if (svm_fifo_set_event (ctx->s->tx_fifo))
-         session_evt_add_old (wrk, elt);
-
-      if (svm_fifo_needs_deq_ntf (ctx->s->tx_fifo, ctx->max_len_to_snd))
+      u32 n_dequeued = ctx->max_len_to_snd;
+      if (ctx->transport_vft->transport_options.tx_type == TRANSPORT_TX_DGRAM)
+       n_dequeued += ctx->n_segs_per_evt * SESSION_CONN_HDR_LEN;
+      if (svm_fifo_needs_deq_ntf (ctx->s->tx_fifo, n_dequeued))
        session_dequeue_notify (ctx->s);
     }
   return SESSION_TX_OK;
@@ -1060,21 +1206,51 @@ session_tx_fifo_dequeue_and_snd (session_worker_t * wrk,
 int
 session_tx_fifo_dequeue_internal (session_worker_t * wrk,
                                  vlib_node_runtime_t * node,
-                                 session_evt_elt_t * e, int *n_tx_packets)
+                                 session_evt_elt_t * elt, int *n_tx_packets)
 {
+  transport_send_params_t *sp = &wrk->ctx.sp;
   session_t *s = wrk->ctx.s;
+  u32 n_packets;
 
   if (PREDICT_FALSE (s->session_state >= SESSION_STATE_TRANSPORT_CLOSED))
     return 0;
-  svm_fifo_unset_event (s->tx_fifo);
-  return transport_custom_tx (session_get_transport_proto (s), s,
-                             VLIB_FRAME_SIZE - *n_tx_packets);
+
+  /* Clear custom-tx flag used to request reschedule for tx */
+  s->flags &= ~SESSION_F_CUSTOM_TX;
+
+  sp->max_burst_size = clib_min (SESSION_NODE_FRAME_SIZE - *n_tx_packets,
+                                TRANSPORT_PACER_MAX_BURST_PKTS);
+
+  n_packets = transport_custom_tx (session_get_transport_proto (s), s, sp);
+  *n_tx_packets += n_packets;
+
+  if (s->flags & SESSION_F_CUSTOM_TX)
+    {
+      session_evt_add_old (wrk, elt);
+    }
+  else if (!(sp->flags & TRANSPORT_SND_F_DESCHED))
+    {
+      svm_fifo_unset_event (s->tx_fifo);
+      if (svm_fifo_max_dequeue_cons (s->tx_fifo))
+       if (svm_fifo_set_event (s->tx_fifo))
+         session_evt_add_head_old (wrk, elt);
+    }
+
+  if (sp->max_burst_size &&
+      svm_fifo_needs_deq_ntf (s->tx_fifo, sp->max_burst_size))
+    session_dequeue_notify (s);
+
+  return n_packets;
 }
 
 always_inline session_t *
-session_event_get_session (session_event_t * e, u8 thread_index)
+session_event_get_session (session_worker_t * wrk, session_event_t * e)
 {
-  return session_get_if_valid (e->session_index, thread_index);
+  if (PREDICT_FALSE (pool_is_free_index (wrk->sessions, e->session_index)))
+    return 0;
+
+  ASSERT (session_is_valid (e->session_index, wrk->vm->thread_index));
+  return pool_elt_at_index (wrk->sessions, e->session_index);
 }
 
 always_inline void
@@ -1143,6 +1319,12 @@ session_event_dispatch_ctrl (session_worker_t * wrk, session_evt_elt_t * elt)
     case SESSION_CTRL_EVT_APP_DETACH:
       app_mq_detach_handler (session_evt_ctrl_data (wrk, elt));
       break;
+    case SESSION_CTRL_EVT_APP_WRK_RPC:
+      session_mq_app_wrk_rpc_handler (session_evt_ctrl_data (wrk, elt));
+      break;
+    case SESSION_CTRL_EVT_TRANSPORT_ATTR:
+      session_mq_transport_attr_handler (session_evt_ctrl_data (wrk, elt));
+      break;
     default:
       clib_warning ("unhandled event type %d", e->event_type);
     }
@@ -1156,12 +1338,12 @@ session_event_dispatch_ctrl (session_worker_t * wrk, session_evt_elt_t * elt)
        session_evt_ctrl_data_free (wrk, elt);
       session_evt_elt_free (wrk, elt);
     }
+  SESSION_EVT (SESSION_EVT_COUNTS, CNT_CTRL_EVTS, 1, wrk);
 }
 
 always_inline void
 session_event_dispatch_io (session_worker_t * wrk, vlib_node_runtime_t * node,
-                          session_evt_elt_t * elt, u32 thread_index,
-                          int *n_tx_packets)
+                          session_evt_elt_t * elt, int *n_tx_packets)
 {
   session_main_t *smm = &session_main;
   app_worker_t *app_wrk;
@@ -1176,7 +1358,7 @@ session_event_dispatch_io (session_worker_t * wrk, vlib_node_runtime_t * node,
     {
     case SESSION_IO_EVT_TX_FLUSH:
     case SESSION_IO_EVT_TX:
-      s = session_event_get_session (e, thread_index);
+      s = session_event_get_session (wrk, e);
       if (PREDICT_FALSE (!s))
        break;
       CLIB_PREFETCH (s->tx_fifo, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
@@ -1186,14 +1368,14 @@ session_event_dispatch_io (session_worker_t * wrk, vlib_node_runtime_t * node,
       (smm->session_tx_fns[s->session_type]) (wrk, node, elt, n_tx_packets);
       break;
     case SESSION_IO_EVT_RX:
-      s = session_event_get_session (e, thread_index);
+      s = session_event_get_session (wrk, e);
       if (!s)
        break;
       transport_app_rx_evt (session_get_transport_proto (s),
                            s->connection_index, s->thread_index);
       break;
     case SESSION_IO_EVT_BUILTIN_RX:
-      s = session_event_get_session (e, thread_index);
+      s = session_event_get_session (wrk, e);
       if (PREDICT_FALSE (!s || s->session_state >= SESSION_STATE_CLOSING))
        break;
       svm_fifo_unset_event (s->rx_fifo);
@@ -1210,6 +1392,8 @@ session_event_dispatch_io (session_worker_t * wrk, vlib_node_runtime_t * node,
       clib_warning ("unhandled event type %d", e->event_type);
     }
 
+  SESSION_EVT (SESSION_IO_EVT_COUNTS, e->event_type, 1, wrk);
+
   /* Regrab elements in case pool moved */
   elt = pool_elt_at_index (wrk->event_elts, ei);
   if (!clib_llist_elt_is_linked (elt, evt_list))
@@ -1264,50 +1448,126 @@ session_flush_pending_tx_buffers (session_worker_t * wrk,
   vec_reset_length (wrk->pending_tx_nexts);
 }
 
+int
+session_wrk_handle_mq (session_worker_t *wrk, svm_msg_q_t *mq)
+{
+  svm_msg_q_msg_t _msg, *msg = &_msg;
+  u32 i, n_to_dequeue = 0;
+  session_event_t *evt;
+
+  n_to_dequeue = svm_msg_q_size (mq);
+  for (i = 0; i < n_to_dequeue; i++)
+    {
+      svm_msg_q_sub_raw (mq, msg);
+      evt = svm_msg_q_msg_data (mq, msg);
+      session_evt_add_to_list (wrk, evt);
+      svm_msg_q_free_msg (mq, msg);
+    }
+
+  return n_to_dequeue;
+}
+
+static void
+session_wrk_timerfd_update (session_worker_t *wrk, u64 time_ns)
+{
+  struct itimerspec its;
+
+  its.it_value.tv_sec = 0;
+  its.it_value.tv_nsec = time_ns;
+  its.it_interval.tv_sec = 0;
+  its.it_interval.tv_nsec = its.it_value.tv_nsec;
+
+  if (timerfd_settime (wrk->timerfd, 0, &its, NULL) == -1)
+    clib_warning ("timerfd_settime");
+}
+
+always_inline u64
+session_wrk_tfd_timeout (session_wrk_state_t state, u32 thread_index)
+{
+  if (state == SESSION_WRK_INTERRUPT)
+    return thread_index ? 1e6 : vlib_num_workers () ? 5e8 : 1e6;
+  else if (state == SESSION_WRK_IDLE)
+    return thread_index ? 1e8 : vlib_num_workers () ? 5e8 : 1e8;
+  else
+    return 0;
+}
+
+static inline void
+session_wrk_set_state (session_worker_t *wrk, session_wrk_state_t state)
+{
+  u64 time_ns;
+
+  wrk->state = state;
+  time_ns = session_wrk_tfd_timeout (state, wrk->vm->thread_index);
+  session_wrk_timerfd_update (wrk, time_ns);
+}
+
+static void
+session_wrk_update_state (session_worker_t *wrk)
+{
+  vlib_main_t *vm = wrk->vm;
+
+  if (wrk->state == SESSION_WRK_POLLING)
+    {
+      if (pool_elts (wrk->event_elts) == 3 &&
+         vlib_last_vectors_per_main_loop (vm) < 1)
+       {
+         session_wrk_set_state (wrk, SESSION_WRK_INTERRUPT);
+         vlib_node_set_state (vm, session_queue_node.index,
+                              VLIB_NODE_STATE_INTERRUPT);
+       }
+    }
+  else if (wrk->state == SESSION_WRK_INTERRUPT)
+    {
+      if (pool_elts (wrk->event_elts) > 3 ||
+         vlib_last_vectors_per_main_loop (vm) > 1)
+       {
+         session_wrk_set_state (wrk, SESSION_WRK_POLLING);
+         vlib_node_set_state (vm, session_queue_node.index,
+                              VLIB_NODE_STATE_POLLING);
+       }
+      else if (PREDICT_FALSE (!pool_elts (wrk->sessions)))
+       {
+         session_wrk_set_state (wrk, SESSION_WRK_IDLE);
+       }
+    }
+  else
+    {
+      if (pool_elts (wrk->event_elts))
+       {
+         session_wrk_set_state (wrk, SESSION_WRK_INTERRUPT);
+       }
+    }
+}
+
 static uword
 session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                       vlib_frame_t * frame)
 {
+  u32 thread_index = vm->thread_index, __clib_unused n_evts;
+  session_evt_elt_t *elt, *ctrl_he, *new_he, *old_he;
   session_main_t *smm = vnet_get_session_main ();
-  u32 thread_index = vm->thread_index, n_to_dequeue;
   session_worker_t *wrk = &smm->wrk[thread_index];
-  session_evt_elt_t *elt, *ctrl_he, *new_he, *old_he;
   clib_llist_index_t ei, next_ei, old_ti;
-  svm_msg_q_msg_t _msg, *msg = &_msg;
-  int i, n_tx_packets;
-  session_event_t *evt;
-  svm_msg_q_t *mq;
+  int n_tx_packets;
 
   SESSION_EVT (SESSION_EVT_DISPATCH_START, wrk);
 
-  wrk->last_vlib_time = vlib_time_now (vm);
-  wrk->last_vlib_us_time = wrk->last_vlib_time * CLIB_US_TIME_FREQ;
+  session_wrk_update_time (wrk, vlib_time_now (vm));
 
   /*
    *  Update transport time
    */
   transport_update_time (wrk->last_vlib_time, thread_index);
   n_tx_packets = vec_len (wrk->pending_tx_buffers);
+  SESSION_EVT (SESSION_EVT_DSP_CNTRS, UPDATE_TIME, wrk);
 
   /*
-   *  Dequeue and handle new events
+   *  Dequeue new internal mq events
    */
 
-  /* Try to dequeue what is available. Don't wait for lock.
-   * XXX: we may need priorities here */
-  mq = wrk->vpp_event_queue;
-  n_to_dequeue = svm_msg_q_size (mq);
-  if (n_to_dequeue && svm_msg_q_try_lock (mq) == 0)
-    {
-      for (i = 0; i < n_to_dequeue; i++)
-       {
-         svm_msg_q_sub_w_lock (mq, msg);
-         evt = svm_msg_q_msg_data (mq, msg);
-         session_evt_add_to_list (wrk, evt);
-         svm_msg_q_free_msg (mq, msg);
-       }
-      svm_msg_q_unlock (mq);
-    }
+  n_evts = session_wrk_handle_mq (wrk, wrk->vpp_event_queue);
+  SESSION_EVT (SESSION_EVT_DSP_CNTRS, MQ_DEQ, wrk, n_evts);
 
   /*
    * Handle control events
@@ -1315,12 +1575,12 @@ session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
 
   ctrl_he = pool_elt_at_index (wrk->event_elts, wrk->ctrl_head);
 
-  /* *INDENT-OFF* */
   clib_llist_foreach_safe (wrk->event_elts, evt_list, ctrl_he, elt, ({
     clib_llist_remove (wrk->event_elts, evt_list, elt);
     session_event_dispatch_ctrl (wrk, elt);
   }));
-  /* *INDENT-ON* */
+
+  SESSION_EVT (SESSION_EVT_DSP_CNTRS, CTRL_EVTS, wrk);
 
   /*
    * Handle the new io events.
@@ -1331,14 +1591,16 @@ session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
   old_ti = clib_llist_prev_index (old_he, evt_list);
 
   ei = clib_llist_next_index (new_he, evt_list);
-  while (ei != wrk->new_head && n_tx_packets < VLIB_FRAME_SIZE)
+  while (ei != wrk->new_head && n_tx_packets < SESSION_NODE_FRAME_SIZE)
     {
       elt = pool_elt_at_index (wrk->event_elts, ei);
       ei = clib_llist_next_index (elt, evt_list);
       clib_llist_remove (wrk->event_elts, evt_list, elt);
-      session_event_dispatch_io (wrk, node, elt, thread_index, &n_tx_packets);
+      session_event_dispatch_io (wrk, node, elt, &n_tx_packets);
     }
 
+  SESSION_EVT (SESSION_EVT_DSP_CNTRS, NEW_IO_EVTS, wrk);
+
   /*
    * Handle the old io events, if we had any prior to processing the new ones
    */
@@ -1348,14 +1610,13 @@ session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
       old_he = pool_elt_at_index (wrk->event_elts, wrk->old_head);
       ei = clib_llist_next_index (old_he, evt_list);
 
-      while (n_tx_packets < VLIB_FRAME_SIZE)
+      while (n_tx_packets < SESSION_NODE_FRAME_SIZE)
        {
          elt = pool_elt_at_index (wrk->event_elts, ei);
          next_ei = clib_llist_next_index (elt, evt_list);
          clib_llist_remove (wrk->event_elts, evt_list, elt);
 
-         session_event_dispatch_io (wrk, node, elt, thread_index,
-                                    &n_tx_packets);
+         session_event_dispatch_io (wrk, node, elt, &n_tx_packets);
 
          if (ei == old_ti)
            break;
@@ -1364,6 +1625,8 @@ session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
        };
     }
 
+  SESSION_EVT (SESSION_EVT_DSP_CNTRS, OLD_IO_EVTS, wrk);
+
   if (vec_len (wrk->pending_tx_buffers))
     session_flush_pending_tx_buffers (wrk, node);
 
@@ -1372,6 +1635,9 @@ session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
 
   SESSION_EVT (SESSION_EVT_DISPATCH_END, wrk, n_tx_packets);
 
+  if (wrk->flags & SESSION_WRK_F_ADAPTIVE)
+    session_wrk_update_state (wrk);
+
   return n_tx_packets;
 }
 
@@ -1389,165 +1655,50 @@ VLIB_REGISTER_NODE (session_queue_node) =
 };
 /* *INDENT-ON* */
 
-void
-dump_thread_0_event_queue (void)
+static clib_error_t *
+session_wrk_tfd_read_ready (clib_file_t *cf)
 {
-  session_main_t *smm = vnet_get_session_main ();
-  vlib_main_t *vm = &vlib_global_main;
-  u32 my_thread_index = vm->thread_index;
-  session_event_t _e, *e = &_e;
-  svm_msg_q_ring_t *ring;
-  session_t *s0;
-  svm_msg_q_msg_t *msg;
-  svm_msg_q_t *mq;
-  int i, index;
-
-  mq = smm->wrk[my_thread_index].vpp_event_queue;
-  index = mq->q->head;
-
-  for (i = 0; i < mq->q->cursize; i++)
-    {
-      msg = (svm_msg_q_msg_t *) (&mq->q->data[0] + mq->q->elsize * index);
-      ring = svm_msg_q_ring (mq, msg->ring_index);
-      clib_memcpy_fast (e, svm_msg_q_msg_data (mq, msg), ring->elsize);
-
-      switch (e->event_type)
-       {
-       case SESSION_IO_EVT_TX:
-         s0 = session_event_get_session (e, my_thread_index);
-         fformat (stdout, "[%04d] TX session %d\n", i, s0->session_index);
-         break;
-
-       case SESSION_CTRL_EVT_CLOSE:
-         s0 = session_get_from_handle (e->session_handle);
-         fformat (stdout, "[%04d] disconnect session %d\n", i,
-                  s0->session_index);
-         break;
-
-       case SESSION_IO_EVT_BUILTIN_RX:
-         s0 = session_event_get_session (e, my_thread_index);
-         fformat (stdout, "[%04d] builtin_rx %d\n", i, s0->session_index);
-         break;
-
-       case SESSION_CTRL_EVT_RPC:
-         fformat (stdout, "[%04d] RPC call %llx with %llx\n",
-                  i, (u64) (uword) (e->rpc_args.fp),
-                  (u64) (uword) (e->rpc_args.arg));
-         break;
-
-       default:
-         fformat (stdout, "[%04d] unhandled event type %d\n",
-                  i, e->event_type);
-         break;
-       }
-
-      index++;
+  session_worker_t *wrk = session_main_get_worker (cf->private_data);
+  u64 buf;
+  int rv;
 
-      if (index == mq->q->maxsize)
-       index = 0;
-    }
+  vlib_node_set_interrupt_pending (wrk->vm, session_queue_node.index);
+  rv = read (wrk->timerfd, &buf, sizeof (buf));
+  if (rv < 0 && errno != EAGAIN)
+    clib_unix_warning ("failed");
+  return 0;
 }
 
-static u8
-session_node_cmp_event (session_event_t * e, svm_fifo_t * f)
+static clib_error_t *
+session_wrk_tfd_write_ready (clib_file_t *cf)
 {
-  session_t *s;
-  switch (e->event_type)
-    {
-    case SESSION_IO_EVT_RX:
-    case SESSION_IO_EVT_TX:
-    case SESSION_IO_EVT_BUILTIN_RX:
-    case SESSION_IO_EVT_BUILTIN_TX:
-    case SESSION_IO_EVT_TX_FLUSH:
-      if (e->session_index == f->master_session_index)
-       return 1;
-      break;
-    case SESSION_CTRL_EVT_CLOSE:
-      break;
-    case SESSION_CTRL_EVT_RPC:
-      s = session_get_from_handle (e->session_handle);
-      if (!s)
-       {
-         clib_warning ("session has event but doesn't exist!");
-         break;
-       }
-      if (s->rx_fifo == f || s->tx_fifo == f)
-       return 1;
-      break;
-    default:
-      break;
-    }
   return 0;
 }
 
-u8
-session_node_lookup_fifo_event (svm_fifo_t * f, session_event_t * e)
+void
+session_wrk_enable_adaptive_mode (session_worker_t *wrk)
 {
-  session_evt_elt_t *elt;
-  session_worker_t *wrk;
-  int i, index, found = 0;
-  svm_msg_q_msg_t *msg;
-  svm_msg_q_ring_t *ring;
-  svm_msg_q_t *mq;
-  u8 thread_index;
+  u32 thread_index = wrk->vm->thread_index;
+  clib_file_t template = { 0 };
 
-  ASSERT (e);
-  thread_index = f->master_thread_index;
-  wrk = session_main_get_worker (thread_index);
+  if ((wrk->timerfd = timerfd_create (CLOCK_MONOTONIC, TFD_NONBLOCK)) < 0)
+    clib_warning ("timerfd_create");
 
-  /*
-   * Search evt queue
-   */
-  mq = wrk->vpp_event_queue;
-  index = mq->q->head;
-  for (i = 0; i < mq->q->cursize; i++)
-    {
-      msg = (svm_msg_q_msg_t *) (&mq->q->data[0] + mq->q->elsize * index);
-      ring = svm_msg_q_ring (mq, msg->ring_index);
-      clib_memcpy_fast (e, svm_msg_q_msg_data (mq, msg), ring->elsize);
-      found = session_node_cmp_event (e, f);
-      if (found)
-       return 1;
-      index = (index + 1) % mq->q->maxsize;
-    }
-  /*
-   * Search pending events vector
-   */
-
-  /* *INDENT-OFF* */
-  clib_llist_foreach (wrk->event_elts, evt_list,
-                      pool_elt_at_index (wrk->event_elts, wrk->new_head),
-                      elt, ({
-    found = session_node_cmp_event (&elt->evt, f);
-    if (found)
-      {
-       clib_memcpy_fast (e, &elt->evt, sizeof (*e));
-       goto done;
-      }
-  }));
-  /* *INDENT-ON* */
-
-  /* *INDENT-OFF* */
-  clib_llist_foreach (wrk->event_elts, evt_list,
-                      pool_elt_at_index (wrk->event_elts, wrk->old_head),
-                      elt, ({
-    found = session_node_cmp_event (&elt->evt, f);
-    if (found)
-      {
-       clib_memcpy_fast (e, &elt->evt, sizeof (*e));
-       goto done;
-      }
-  }));
-  /* *INDENT-ON* */
+  template.read_function = session_wrk_tfd_read_ready;
+  template.write_function = session_wrk_tfd_write_ready;
+  template.file_descriptor = wrk->timerfd;
+  template.private_data = thread_index;
+  template.polling_thread_index = thread_index;
+  template.description = format (0, "session-wrk-tfd-%u", thread_index);
 
-done:
-  return found;
+  wrk->timerfd_file = clib_file_add (&file_main, &template);
+  wrk->flags |= SESSION_WRK_F_ADAPTIVE;
 }
 
 static clib_error_t *
 session_queue_exit (vlib_main_t * vm)
 {
-  if (vec_len (vlib_mains) < 2)
+  if (vlib_get_n_threads () < 2)
     return 0;
 
   /*
@@ -1592,6 +1743,8 @@ session_queue_process (vlib_main_t * vm, vlib_node_runtime_t * rt,
          session_queue_run_on_main (vm);
          break;
        case SESSION_Q_PROCESS_STOP:
+         vlib_node_set_state (vm, session_queue_process_node.index,
+                              VLIB_NODE_STATE_DISABLED);
          timeout = 100000.0;
          break;
        case ~0: