PPPoE usses a midchain adjacency stack on an interface-tx DPO

1) introduce an interface-tx DPO. This is a simple wrapper around a sw_if_index. enhance DPO stacking functions to allow per-instance next-nodes and hence allow children to stack onto the interface per-instance tx node and not on 'interface-output'.
2) update PPPoE code to use ta midchain stack on a interface-tx DPO of the encap-interface. This remove the need for pppoe_encap node (which is replaced by the adj-midchain-tx) and interface-output node is no longer used (see above). Since PPPoE encap node is no longer needed, the PPPoE seesion does not need to be retrieved in the data-path, hence the cahce misses are removed.

Change-Id: Id8b40f53daa14889a9c51d802e14fed7fba4399a
Signed-off-by: Neale Ranns <nranns@cisco.com>

4 files changed, 122 insertions, 435 deletions

diff --git a/src/plugins/pppoe.am b/src/plugins/pppoe.am
index 28bd20a0425..06ed60b4978 100644
--- a/src/plugins/pppoe.am
+++ b/src/plugins/pppoe.am
@@ -14,27 +14,26 @@
 vppapitestplugins_LTLIBRARIES += pppoe_test_plugin.la
 vppplugins_LTLIBRARIES += pppoe_plugin.la
 
-pppoe_plugin_la_SOURCES =		\
-    pppoe/pppoe_decap.c		    \
-    pppoe/pppoe_encap.c		    \
-    pppoe/pppoe_tap.c		    \
-    pppoe/pppoe_tap_node.c		\
-    pppoe/pppoe.c		        \
+pppoe_plugin_la_SOURCES =	\
+    pppoe/pppoe_decap.c		\
+    pppoe/pppoe_tap.c		\
+    pppoe/pppoe_tap_node.c	\
+    pppoe/pppoe.c		\
     pppoe/pppoe_api.c
 
-BUILT_SOURCES +=			   \
-    pppoe/pppoe.api.h		    \
+BUILT_SOURCES +=		\
+    pppoe/pppoe.api.h		\
     pppoe/pppoe.api.json
 
 API_FILES += pppoe/pppoe.api
 
 nobase_apiinclude_HEADERS +=	\
-    pppoe/pppoe_all_api_h.h		\
-    pppoe/pppoe_msg_enum.h		\
+    pppoe/pppoe_all_api_h.h	\
+    pppoe/pppoe_msg_enum.h	\
     pppoe/pppoe.api.h
 
-pppoe_test_plugin_la_SOURCES = \
-    pppoe/pppoe_test.c            \
+pppoe_test_plugin_la_SOURCES =	\
+    pppoe/pppoe_test.c		\
     pppoe/pppoe_plugin.api.h
 
 # vi:syntax=automake
diff --git a/src/plugins/pppoe/pppoe.c b/src/plugins/pppoe/pppoe.c
index cb587e2934b..e09ac7d993e 100644
--- a/src/plugins/pppoe/pppoe.c
+++ b/src/plugins/pppoe/pppoe.c
@@ -24,11 +24,13 @@
 #include <vnet/ethernet/ethernet.h>
 #include <vnet/fib/fib_entry.h>
 #include <vnet/fib/fib_table.h>
-#include <vnet/dpo/dpo.h>
+#include <vnet/dpo/interface_tx_dpo.h>
 #include <vnet/plugin/plugin.h>
 #include <vpp/app/version.h>
 #include <vnet/ppp/packet.h>
 #include <pppoe/pppoe.h>
+#include <vnet/adj/adj_midchain.h>
+#include <vnet/adj/adj_mcast.h>
 
 #include <vppinfra/hash.h>
 #include <vppinfra/bihash_template.c>
@@ -85,7 +87,6 @@ pppoe_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags)
 VNET_DEVICE_CLASS (pppoe_device_class,static) = {
   .name = "PPPPOE",
   .format_device_name = format_pppoe_name,
-  .format_tx_trace = format_pppoe_encap_trace,
   .tx_function = dummy_interface_tx,
   .admin_up_down_function = pppoe_interface_admin_up_down,
 };
@@ -99,27 +100,19 @@ format_pppoe_header_with_length (u8 * s, va_list * args)
   return s;
 }
 
-/* *INDENT-OFF* */
-VNET_HW_INTERFACE_CLASS (pppoe_hw_class) =
-{
-  .name = "PPPPOE",
-  .format_header = format_pppoe_header_with_length,
-  .build_rewrite = default_build_rewrite,
-  .flags = VNET_HW_INTERFACE_CLASS_FLAG_P2P,
-};
-/* *INDENT-ON* */
-
-#define foreach_copy_field                      \
-_(session_id)                                   \
-_(encap_if_index)                               \
-_(decap_fib_index)                              \
-_(client_ip)
-
-static void
-eth_pppoe_rewrite (pppoe_session_t * t, bool is_ip6)
+static u8 *
+pppoe_build_rewrite (vnet_main_t * vnm,
+		     u32 sw_if_index,
+		     vnet_link_t link_type, const void *dst_address)
 {
-  u8 *rw = 0;
   int len = sizeof (pppoe_header_t) + sizeof (ethernet_header_t);
+  pppoe_main_t *pem = &pppoe_main;
+  pppoe_session_t *t;
+  u32 session_id;
+  u8 *rw = 0;
+
+  session_id = pem->session_index_by_sw_if_index[sw_if_index];
+  t = pool_elt_at_index (pem->sessions, session_id);
 
   vec_validate_aligned (rw, len - 1, CLIB_CACHE_LINE_BYTES);
 
@@ -134,21 +127,112 @@ eth_pppoe_rewrite (pppoe_session_t * t, bool is_ip6)
   pppoe->session_id = clib_host_to_net_u16 (t->session_id);
   pppoe->length = 0;		/* To be filled in at run-time */
 
-  if (!is_ip6)
+  switch (link_type)
     {
+    case VNET_LINK_IP4:
       pppoe->ppp_proto = clib_host_to_net_u16 (PPP_PROTOCOL_ip4);
+      break;
+    case VNET_LINK_IP6:
+      pppoe->ppp_proto = clib_host_to_net_u16 (PPP_PROTOCOL_ip6);
+      break;
+    default:
+      break;
     }
-  else
+
+  return rw;
+}
+
+/**
+ * @brief Fixup the adj rewrite post encap. Insert the packet's length
+ */
+static void
+pppoe_fixup (vlib_main_t * vm, ip_adjacency_t * adj, vlib_buffer_t * b0)
+{
+  pppoe_header_t *pppoe0;
+
+  pppoe0 = vlib_buffer_get_current (b0);
+
+  pppoe0->length = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
+					 - sizeof (pppoe_header_t)
+					 - sizeof (ethernet_header_t));
+}
+
+static void
+pppoe_update_adj (vnet_main_t * vnm, u32 sw_if_index, adj_index_t ai)
+{
+  pppoe_main_t *pem = &pppoe_main;
+  dpo_id_t dpo = DPO_INVALID;
+  ip_adjacency_t *adj;
+  pppoe_session_t *t;
+  u32 session_id;
+
+  ASSERT (ADJ_INDEX_INVALID != ai);
+
+  adj = adj_get (ai);
+
+  switch (adj->lookup_next_index)
     {
-      pppoe->ppp_proto = clib_host_to_net_u16 (PPP_PROTOCOL_ip6);
+    case IP_LOOKUP_NEXT_ARP:
+    case IP_LOOKUP_NEXT_GLEAN:
+      adj_nbr_midchain_update_rewrite (ai, pppoe_fixup,
+				       ADJ_FLAG_NONE,
+				       pppoe_build_rewrite (vnm,
+							    sw_if_index,
+							    adj->ia_link,
+							    NULL));
+      break;
+    case IP_LOOKUP_NEXT_MCAST:
+      /*
+       * Construct a partial rewrite from the known ethernet mcast dest MAC
+       * There's no MAC fixup, so the last 2 parameters are 0
+       */
+      adj_mcast_midchain_update_rewrite (ai, pppoe_fixup,
+					 ADJ_FLAG_NONE,
+					 pppoe_build_rewrite (vnm,
+							      sw_if_index,
+							      adj->ia_link,
+							      NULL), 0, 0);
+      break;
+
+    case IP_LOOKUP_NEXT_DROP:
+    case IP_LOOKUP_NEXT_PUNT:
+    case IP_LOOKUP_NEXT_LOCAL:
+    case IP_LOOKUP_NEXT_REWRITE:
+    case IP_LOOKUP_NEXT_MIDCHAIN:
+    case IP_LOOKUP_NEXT_MCAST_MIDCHAIN:
+    case IP_LOOKUP_NEXT_ICMP_ERROR:
+    case IP_LOOKUP_N_NEXT:
+      ASSERT (0);
+      break;
     }
 
-  t->rewrite = rw;
-  _vec_len (t->rewrite) = len;
+  session_id = pem->session_index_by_sw_if_index[sw_if_index];
+  t = pool_elt_at_index (pem->sessions, session_id);
+  interface_tx_dpo_add_or_lock (vnet_link_to_dpo_proto (adj->ia_link),
+				t->encap_if_index, &dpo);
+
+  adj_nbr_midchain_stack (ai, &dpo);
 
-  return;
+  dpo_reset (&dpo);
 }
 
+/* *INDENT-OFF* */
+VNET_HW_INTERFACE_CLASS (pppoe_hw_class) =
+{
+  .name = "PPPPOE",
+  .format_header = format_pppoe_header_with_length,
+  .build_rewrite = pppoe_build_rewrite,
+  .update_adjacency = pppoe_update_adj,
+  .flags = VNET_HW_INTERFACE_CLASS_FLAG_P2P,
+};
+/* *INDENT-ON* */
+
+#define foreach_copy_field                      \
+_(session_id)                                   \
+_(encap_if_index)                               \
+_(decap_fib_index)                              \
+_(client_ip)
+
 static bool
 pppoe_decap_next_is_valid (pppoe_main_t * pem, u32 is_ip6,
 			   u32 decap_fib_index)
@@ -231,8 +315,6 @@ int vnet_pppoe_add_del_session
 
       clib_memcpy (t->client_mac, a->client_mac, 6);
 
-      eth_pppoe_rewrite (t, is_ip6);
-
       /* update pppoe fib with session_index */
       result.fields.session_index = t - pem->sessions;
       pppoe_update_1 (&pem->session_table,
@@ -285,9 +367,6 @@ int vnet_pppoe_add_del_session
       vnet_sw_interface_set_flags (vnm, sw_if_index,
 				   VNET_SW_INTERFACE_FLAG_ADMIN_UP);
 
-      /* Set pppoe session output node */
-      hi->output_node_index = pppoe_encap_node.index;
-
       /* add reverse route for client ip */
       fib_table_entry_path_add (a->decap_fib_index, &pfx,
 				FIB_SOURCE_PLUGIN_HI, FIB_ENTRY_FLAG_NONE,
@@ -328,7 +407,6 @@ int vnet_pppoe_add_del_session
 				   sw_if_index, ~0, 1,
 				   FIB_ROUTE_PATH_FLAG_NONE);
 
-      vec_free (t->rewrite);
       pool_put (pem->sessions, t);
     }
 
diff --git a/src/plugins/pppoe/pppoe.h b/src/plugins/pppoe/pppoe.h
index 37d628eb903..b06c068f405 100644
--- a/src/plugins/pppoe/pppoe.h
+++ b/src/plugins/pppoe/pppoe.h
@@ -48,9 +48,6 @@ typedef struct
 
 typedef struct
 {
-  /* Rewrite string */
-  u8 *rewrite;
-
   /* pppoe session_id in HOST byte order */
   u16 session_id;
 
@@ -177,11 +174,8 @@ typedef struct
 extern pppoe_main_t pppoe_main;
 
 extern vlib_node_registration_t pppoe_input_node;
-extern vlib_node_registration_t pppoe_encap_node;
 extern vlib_node_registration_t pppoe_tap_dispatch_node;
 
-u8 *format_pppoe_encap_trace (u8 * s, va_list * args);
-
 typedef struct
 {
   u8 is_add;
diff --git a/src/plugins/pppoe/pppoe_encap.c b/src/plugins/pppoe/pppoe_encap.c
deleted file mode 100644
index 69bec61dec1..00000000000
--- a/src/plugins/pppoe/pppoe_encap.c
+++ /dev/null
@@ -1,384 +0,0 @@
-/*
- * Copyright (c) 2017 Intel and/or its affiliates.
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at:
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-#include <vppinfra/error.h>
-#include <vppinfra/hash.h>
-#include <vnet/vnet.h>
-#include <vnet/ip/ip.h>
-#include <vnet/ethernet/ethernet.h>
-#include <pppoe/pppoe.h>
-
-/* Statistics (not all errors) */
-#define foreach_pppoe_encap_error    \
-_(ENCAPSULATED, "good packets encapsulated")
-
-static char * pppoe_encap_error_strings[] = {
-#define _(sym,string) string,
-  foreach_pppoe_encap_error
-#undef _
-};
-
-typedef enum {
-#define _(sym,str) PPPOE_ENCAP_ERROR_##sym,
-    foreach_pppoe_encap_error
-#undef _
-    PPPOE_ENCAP_N_ERROR,
-} pppoe_encap_error_t;
-
-#define foreach_pppoe_encap_next       \
-_(DROP, "error-drop")                  \
-_(INTERFACE, "interface-output" )      \
-
-typedef enum
-{
-#define _(s,n) PPPOE_ENCAP_NEXT_##s,
-  foreach_pppoe_encap_next
-#undef _
-    PPPOE_ENCAP_N_NEXT,
-} pppoe_encap_next_t;
-
-typedef struct {
-  u32 session_index;
-  u32 session_id;
-} pppoe_encap_trace_t;
-
-u8 * format_pppoe_encap_trace (u8 * s, va_list * args)
-{
-  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
-  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
-  pppoe_encap_trace_t * t
-      = va_arg (*args, pppoe_encap_trace_t *);
-
-  s = format (s, "PPPOE encap to pppoe_session%d session_id %d",
-	      t->session_index, t->session_id);
-  return s;
-}
-
-
-#define foreach_fixed_header2_offset            \
-        _(0) _(1)
-
-
-static uword
-pppoe_encap (vlib_main_t * vm,
-	      vlib_node_runtime_t * node,
-	      vlib_frame_t * from_frame)
-{
-  u32 n_left_from, next_index, * from, * to_next;
-  pppoe_main_t * pem = &pppoe_main;
-  vnet_main_t * vnm = pem->vnet_main;
-  vnet_interface_main_t * im = &vnm->interface_main;
-  u32 pkts_encapsulated = 0;
-  u32 thread_index = vlib_get_thread_index();
-  u32 stats_sw_if_index, stats_n_packets, stats_n_bytes;
-  u32 sw_if_index0 = 0, sw_if_index1 = 0;
-  u32 next0 = 0, next1 = 0;
-  pppoe_session_t * t0 = NULL, * t1 = NULL;
-
-  from = vlib_frame_vector_args (from_frame);
-  n_left_from = from_frame->n_vectors;
-
-  next_index = node->cached_next_index;
-  stats_sw_if_index = node->runtime_data[0];
-  stats_n_packets = stats_n_bytes = 0;
-
-  while (n_left_from > 0)
-    {
-      u32 n_left_to_next;
-
-      vlib_get_next_frame (vm, node, next_index,
-			   to_next, n_left_to_next);
-
-      while (n_left_from >= 4 && n_left_to_next >= 2)
-	{
-          u32 bi0, bi1;
-	  vlib_buffer_t * b0, * b1;
-	  u32 len0, len1;
-	  ethernet_header_t * eth0, * eth1;
-          pppoe_header_t * pppoe0, * pppoe1;
-          u64 * copy_src0, * copy_dst0;
-          u64 * copy_src1, * copy_dst1;
-          u16 * copy_src_last0, * copy_dst_last0;
-          u16 * copy_src_last1, * copy_dst_last1;
-          u16 new_l0, new_l1;
-          u32 session_id0, session_id1;
-
-	  /* Prefetch next iteration. */
-	  {
-	    vlib_buffer_t * p2, * p3;
-
-	    p2 = vlib_get_buffer (vm, from[2]);
-	    p3 = vlib_get_buffer (vm, from[3]);
-
-	    vlib_prefetch_buffer_header (p2, LOAD);
-	    vlib_prefetch_buffer_header (p3, LOAD);
-
-	    CLIB_PREFETCH (p2->data, 2*CLIB_CACHE_LINE_BYTES, LOAD);
-	    CLIB_PREFETCH (p3->data, 2*CLIB_CACHE_LINE_BYTES, LOAD);
-	  }
-
-	  bi0 = from[0];
-	  bi1 = from[1];
-	  to_next[0] = bi0;
-	  to_next[1] = bi1;
-	  from += 2;
-	  to_next += 2;
-	  n_left_to_next -= 2;
-	  n_left_from -= 2;
-
-	  b0 = vlib_get_buffer (vm, bi0);
-	  b1 = vlib_get_buffer (vm, bi1);
-
-	  /* Get next node index and if-index from session */
-	  sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_TX];
-	  session_id0 = pem->session_index_by_sw_if_index[sw_if_index0];
-	  t0 = pool_elt_at_index(pem->sessions, session_id0);
-	  next0 = PPPOE_ENCAP_NEXT_INTERFACE;
-          vnet_buffer(b0)->sw_if_index[VLIB_TX] = t0->encap_if_index;
-
-          /* Get next node index and if-index from session */
-	  sw_if_index1 = vnet_buffer(b1)->sw_if_index[VLIB_TX];
-	  session_id1 = pem->session_index_by_sw_if_index[sw_if_index1];
-	  t1 = pool_elt_at_index(pem->sessions, session_id1);
-	  next1 = PPPOE_ENCAP_NEXT_INTERFACE;
-          vnet_buffer(b1)->sw_if_index[VLIB_TX] = t1->encap_if_index;
-
-          /* Apply the rewrite string. $$$$ vnet_rewrite? */
-          vlib_buffer_advance (b0, -(word)_vec_len(t0->rewrite));
-          vlib_buffer_advance (b1, -(word)_vec_len(t1->rewrite));
-
-          eth0 = (ethernet_header_t *)(vlib_buffer_get_current(b0));
-          eth1 = (ethernet_header_t *)(vlib_buffer_get_current(b1));
-
-	  /* Copy the fixed header */
-	  copy_dst0 = (u64 *) eth0;
-	  copy_src0 = (u64 *) t0->rewrite;
-	  copy_dst1 = (u64 *) eth1;
-	  copy_src1 = (u64 *) t1->rewrite;
-	  /* Copy first 8-bytes at a time */
-#define _(offs) copy_dst0[offs] = copy_src0[offs];
-	  foreach_fixed_header2_offset;
-#undef _
-	  /* Last 6 octets. Hopefully gcc will be our friend */
-          copy_dst_last0 = (u16 *)(&copy_dst0[2]);
-          copy_src_last0 = (u16 *)(&copy_src0[2]);
-          copy_dst_last0[0] = copy_src_last0[0];
-          copy_dst_last0[1] = copy_src_last0[1];
-          copy_dst_last0[2] = copy_src_last0[2];
-
-#define _(offs) copy_dst1[offs] = copy_src1[offs];
-	  foreach_fixed_header2_offset;
-#undef _
-	  /* Last 6 octets. Hopefully gcc will be our friend */
-          copy_dst_last1 = (u16 *)(&copy_dst1[2]);
-          copy_src_last1 = (u16 *)(&copy_src1[2]);
-          copy_dst_last1[0] = copy_src_last1[0];
-          copy_dst_last1[1] = copy_src_last1[1];
-          copy_dst_last1[2] = copy_src_last1[2];
-
-          /* Fix PPPoE length */
-	  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain(vm, b0)
-					 - sizeof (*pppoe0) - sizeof(*eth0));
-	  pppoe0 = (pppoe_header_t *)(eth0 + 1);
-	  pppoe0->length = new_l0;
-
-	  new_l1 = clib_host_to_net_u16 (vlib_buffer_length_in_chain(vm, b1)
-					 - sizeof (*pppoe1) - sizeof(*eth1));
-	  pppoe1 = (pppoe_header_t *)(eth1 + 1);
-	  pppoe1->length = new_l1;
-
-          pkts_encapsulated += 2;
- 	  len0 = vlib_buffer_length_in_chain (vm, b0);
- 	  len1 = vlib_buffer_length_in_chain (vm, b1);
-	  stats_n_packets += 2;
-	  stats_n_bytes += len0 + len1;
-
-	  /* Batch stats increment on the same pppoe session so counter is not
-	     incremented per packet. Note stats are still incremented for deleted
-	     and admin-down session where packets are dropped. It is not worthwhile
-	     to check for this rare case and affect normal path performance. */
-	  if (PREDICT_FALSE ((sw_if_index0 != stats_sw_if_index) ||
-			     (sw_if_index1 != stats_sw_if_index)))
-	    {
-	      stats_n_packets -= 2;
-	      stats_n_bytes -= len0 + len1;
-	      if (sw_if_index0 == sw_if_index1)
-	        {
-		  if (stats_n_packets)
-		    vlib_increment_combined_counter
-		      (im->combined_sw_if_counters + VNET_INTERFACE_COUNTER_TX,
-		       thread_index, stats_sw_if_index,
-		       stats_n_packets, stats_n_bytes);
-		  stats_sw_if_index = sw_if_index0;
-		  stats_n_packets = 2;
-		  stats_n_bytes = len0 + len1;
-	        }
-	      else
-	        {
-		  vlib_increment_combined_counter
-		      (im->combined_sw_if_counters + VNET_INTERFACE_COUNTER_TX,
-		       thread_index, sw_if_index0, 1, len0);
-		  vlib_increment_combined_counter
-		      (im->combined_sw_if_counters + VNET_INTERFACE_COUNTER_TX,
-		       thread_index, sw_if_index1, 1, len1);
-		}
-	    }
-
-	  if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
-            {
-              pppoe_encap_trace_t *tr =
-                vlib_add_trace (vm, node, b0, sizeof (*tr));
-              tr->session_index = t0 - pem->sessions;
-              tr->session_id = t0->session_id;
-           }
-
-          if (PREDICT_FALSE(b1->flags & VLIB_BUFFER_IS_TRACED))
-            {
-              pppoe_encap_trace_t *tr =
-                vlib_add_trace (vm, node, b1, sizeof (*tr));
-              tr->session_index = t1 - pem->sessions;
-              tr->session_id = t1->session_id;
-            }
-
-	  vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
-					   to_next, n_left_to_next,
-					   bi0, bi1, next0, next1);
-	}
-
-      while (n_left_from > 0 && n_left_to_next > 0)
-	{
-	  u32 bi0;
-	  vlib_buffer_t * b0;
-	  ethernet_header_t * eth0;
-          pppoe_header_t * pppoe0;
-          u64 * copy_src0, * copy_dst0;
-          u16 * copy_src_last0, * copy_dst_last0;
-          u16 new_l0;
-          u32 len0;
-          u32 session_id0;
-
-	  bi0 = from[0];
-	  to_next[0] = bi0;
-	  from += 1;
-	  to_next += 1;
-	  n_left_from -= 1;
-	  n_left_to_next -= 1;
-
-	  b0 = vlib_get_buffer (vm, bi0);
-
-	  /* Get next node index and if-index from session */
-	  sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_TX];
-	  session_id0 = pem->session_index_by_sw_if_index[sw_if_index0];
-	  t0 = pool_elt_at_index(pem->sessions, session_id0);
-	  next0 = PPPOE_ENCAP_NEXT_INTERFACE;
-          vnet_buffer(b0)->sw_if_index[VLIB_TX] = t0->encap_if_index;
-
-          /* Apply the rewrite string. $$$$ vnet_rewrite? */
-          vlib_buffer_advance (b0, -(word)_vec_len(t0->rewrite));
-
-          eth0 = (ethernet_header_t *)(vlib_buffer_get_current(b0));
-	  /* Copy the fixed header */
-	  copy_dst0 = (u64 *) eth0;
-	  copy_src0 = (u64 *) t0->rewrite;
-
-	  /* Copy first 8-bytes at a time */
-#define _(offs) copy_dst0[offs] = copy_src0[offs];
-	  foreach_fixed_header2_offset;
-#undef _
-	  /* Last 6 octets. Hopefully gcc will be our friend */
-          copy_dst_last0 = (u16 *)(&copy_dst0[2]);
-          copy_src_last0 = (u16 *)(&copy_src0[2]);
-          copy_dst_last0[0] = copy_src_last0[0];
-          copy_dst_last0[1] = copy_src_last0[1];
-          copy_dst_last0[2] = copy_src_last0[2];
-
-          /* Fix PPPoE length */
-	  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain(vm, b0)
-					 - sizeof (*pppoe0) - sizeof(*eth0));
-	  pppoe0 = (pppoe_header_t *)(eth0 + 1);
-	  pppoe0->length = new_l0;
-
-          pkts_encapsulated ++;
-	  len0 = vlib_buffer_length_in_chain (vm, b0);
-	  stats_n_packets += 1;
-	  stats_n_bytes += len0;
-
-	  /* Batch stats increment on the same pppoe session so counter is not
-	     incremented per packet. Note stats are still incremented for deleted
-	     and admin-down session where packets are dropped. It is not worthwhile
-	     to check for this rare case and affect normal path performance. */
-	  if (PREDICT_FALSE (sw_if_index0 != stats_sw_if_index))
-	    {
-	      stats_n_packets -= 1;
-	      stats_n_bytes -= len0;
-	      if (stats_n_packets)
-		vlib_increment_combined_counter
-		  (im->combined_sw_if_counters + VNET_INTERFACE_COUNTER_TX,
-		   thread_index, stats_sw_if_index,
-		   stats_n_packets, stats_n_bytes);
-	      stats_n_packets = 1;
-	      stats_n_bytes = len0;
-	      stats_sw_if_index = sw_if_index0;
-	    }
-
-          if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
-            {
-              pppoe_encap_trace_t *tr =
-                vlib_add_trace (vm, node, b0, sizeof (*tr));
-              tr->session_index = t0 - pem->sessions;
-              tr->session_id = t0->session_id;
-            }
-	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
-					   to_next, n_left_to_next,
-					   bi0, next0);
-	}
-
-      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
-    }
-
-  /* Do we still need this now that session tx stats is kept? */
-  vlib_node_increment_counter (vm, node->node_index,
-                               PPPOE_ENCAP_ERROR_ENCAPSULATED,
-                               pkts_encapsulated);
-
-  /* Increment any remaining batch stats */
-  if (stats_n_packets)
-    {
-      vlib_increment_combined_counter
-	(im->combined_sw_if_counters + VNET_INTERFACE_COUNTER_TX,
-	 thread_index, stats_sw_if_index, stats_n_packets, stats_n_bytes);
-      node->runtime_data[0] = stats_sw_if_index;
-    }
-
-  return from_frame->n_vectors;
-}
-
-VLIB_REGISTER_NODE (pppoe_encap_node) = {
-  .function = pppoe_encap,
-  .name = "pppoe-encap",
-  .vector_size = sizeof (u32),
-  .format_trace = format_pppoe_encap_trace,
-  .type = VLIB_NODE_TYPE_INTERNAL,
-  .n_errors = ARRAY_LEN(pppoe_encap_error_strings),
-  .error_strings = pppoe_encap_error_strings,
-  .n_next_nodes = PPPOE_ENCAP_N_NEXT,
-  .next_nodes = {
-#define _(s,n) [PPPOE_ENCAP_NEXT_##s] = n,
-    foreach_pppoe_encap_next
-#undef _
-  },
-};
-
-VLIB_NODE_FUNCTION_MULTIARCH (pppoe_encap_node, pppoe_encap)
-