Tune the ethernet input untagged l2-bridging case

Change-Id: I62fe0834e1031e191787a26452fb167c33e30ffd
Signed-off-by: Dave Barach <dave@barachs.net>

diff --git a/vnet/vnet/ethernet/node.c b/vnet/vnet/ethernet/node.c
index aaa0434..c8dc05e 100644 (file)
--- a/vnet/vnet/ethernet/node.c
+++ b/vnet/vnet/ethernet/node.c
@@ -292,6 +292,8 @@ ethernet_input_inline (vlib_main_t * vm,
   u32 n_left_from, next_index, *from, *to_next;
   u32 stats_sw_if_index, stats_n_packets, stats_n_bytes;
   u32 cpu_index = os_get_cpu_number ();
+  u32 cached_sw_if_index = ~0;
+  u32 cached_is_l2 = 0;                /* shut up gcc */
 
   if (variant != ETHERNET_INPUT_VARIANT_ETHERNET)
     error_node = vlib_node_get_runtime (vm, ethernet_input_node.index);
@@ -333,6 +335,7 @@ ethernet_input_inline (vlib_main_t * vm,
          vlan_intf_t *vlan_intf0, *vlan_intf1;
          qinq_intf_t *qinq_intf0, *qinq_intf1;
          u32 is_l20, is_l21;
+         ethernet_header_t *e0, *e1;
 
          /* Prefetch next iteration. */
          {
@@ -361,6 +364,51 @@ ethernet_input_inline (vlib_main_t * vm,
          b1 = vlib_get_buffer (vm, bi1);
 
          error0 = error1 = ETHERNET_ERROR_NONE;
+         e0 = vlib_buffer_get_current (b0);
+         type0 = clib_net_to_host_u16 (e0->type);
+         e1 = vlib_buffer_get_current (b1);
+         type1 = clib_net_to_host_u16 (e1->type);
+
+         /* Speed-path for the untagged L2 case */
+         if (PREDICT_TRUE (variant == ETHERNET_INPUT_VARIANT_ETHERNET
+                           && !ethernet_frame_is_tagged (type0)
+                           && !ethernet_frame_is_tagged (type1)))
+           {
+             main_intf_t *intf0;
+             subint_config_t *subint0;
+             u32 sw_if_index0, sw_if_index1;
+
+             sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+             sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
+             is_l20 = cached_is_l2;
+
+             /* This is probably wholly unnecessary */
+             if (PREDICT_FALSE (sw_if_index0 != sw_if_index1))
+               goto slowpath;
+
+             if (PREDICT_FALSE (cached_sw_if_index != sw_if_index0))
+               {
+                 cached_sw_if_index = sw_if_index0;
+                 hi0 = vnet_get_sup_hw_interface (vnm, sw_if_index0);
+                 intf0 = vec_elt_at_index (em->main_intfs, hi0->hw_if_index);
+                 subint0 = &intf0->untagged_subint;
+                 cached_is_l2 = is_l20 = subint0->flags & SUBINT_CONFIG_L2;
+               }
+             if (PREDICT_TRUE (is_l20 != 0))
+               {
+                 next0 = em->l2_next;
+                 vnet_buffer (b0)->l2.l2_len = sizeof (ethernet_header_t);
+                 vnet_buffer (b0)->ethernet.start_of_ethernet_header =
+                   b0->current_data;
+                 next1 = em->l2_next;
+                 vnet_buffer (b1)->l2.l2_len = sizeof (ethernet_header_t);
+                 vnet_buffer (b1)->ethernet.start_of_ethernet_header =
+                   b1->current_data;
+                 goto ship_it01;
+               }
+             /* FALLTHROUGH into the general case */
+           }
+       slowpath:
 
          parse_header (variant,
                        b0,
@@ -484,6 +532,7 @@ ethernet_input_inline (vlib_main_t * vm,
          b0->error = error_node->errors[error0];
          b1->error = error_node->errors[error1];
 
+       ship_it01:
          // verify speculative enqueue
          vlib_validate_buffer_enqueue_x2 (vm, node, next_index, to_next,
                                           n_left_to_next, bi0, bi1, next0,
@@ -503,6 +552,7 @@ ethernet_input_inline (vlib_main_t * vm,
          main_intf_t *main_intf0;
          vlan_intf_t *vlan_intf0;
          qinq_intf_t *qinq_intf0;
+         ethernet_header_t *e0;
          u32 is_l20;
 
          // Prefetch next iteration
@@ -525,6 +575,38 @@ ethernet_input_inline (vlib_main_t * vm,
          b0 = vlib_get_buffer (vm, bi0);
 
          error0 = ETHERNET_ERROR_NONE;
+         e0 = vlib_buffer_get_current (b0);
+         type0 = clib_net_to_host_u16 (e0->type);
+
+         /* Speed-path for the untagged L2 case */
+         if (PREDICT_TRUE (variant == ETHERNET_INPUT_VARIANT_ETHERNET
+                           && !ethernet_frame_is_tagged (type0)))
+           {
+             main_intf_t *intf0;
+             subint_config_t *subint0;
+             u32 sw_if_index0;
+
+             sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+             is_l20 = cached_is_l2;
+
+             if (PREDICT_FALSE (cached_sw_if_index != sw_if_index0))
+               {
+                 cached_sw_if_index = sw_if_index0;
+                 hi0 = vnet_get_sup_hw_interface (vnm, sw_if_index0);
+                 intf0 = vec_elt_at_index (em->main_intfs, hi0->hw_if_index);
+                 subint0 = &intf0->untagged_subint;
+                 cached_is_l2 = is_l20 = subint0->flags & SUBINT_CONFIG_L2;
+               }
+             if (PREDICT_TRUE (is_l20 != 0))
+               {
+                 next0 = em->l2_next;
+                 vnet_buffer (b0)->l2.l2_len = sizeof (ethernet_header_t);
+                 vnet_buffer (b0)->ethernet.start_of_ethernet_header =
+                   b0->current_data;
+                 goto ship_it0;
+               }
+             /* FALLTHROUGH into the general case */
+           }
 
          parse_header (variant,
                        b0,
@@ -607,6 +689,7 @@ ethernet_input_inline (vlib_main_t * vm,
          b0->error = error_node->errors[error0];
 
          // verify speculative enqueue
+       ship_it0:
          vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
                                           to_next, n_left_to_next,
                                           bi0, next0);