nat: perf improvement - replace branchy code

Use a lookup table instead.

Type: improvement
Signed-off-by: Klement Sekera <ksekera@cisco.com>
Change-Id: Ia8461099828bb8824bf016201f135e6b69c444d1

1 files changed, 28 insertions, 28 deletions

diff --git a/src/plugins/nat/out2in.c b/src/plugins/nat/out2in.c
index 61719c73081..94679fb402c 100755
--- a/src/plugins/nat/out2in.c
+++ b/src/plugins/nat/out2in.c
@@ -278,7 +278,7 @@ static_always_inline
   if (!icmp_type_is_error_message
       (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags))
     {
-      key0.protocol = SNAT_PROTOCOL_ICMP;
+      key0.protocol = NAT_PROTOCOL_ICMP;
       key0.addr = ip0->dst_address;
       key0.port = vnet_buffer (b)->ip.reass.l4_src_port;	// TODO should this be dst port?
     }
@@ -286,17 +286,17 @@ static_always_inline
     {
       inner_ip0 = (ip4_header_t *) (echo0 + 1);
       l4_header = ip4_next_header (inner_ip0);
-      key0.protocol = ip_proto_to_snat_proto (inner_ip0->protocol);
+      key0.protocol = ip_proto_to_nat_proto (inner_ip0->protocol);
       key0.addr = inner_ip0->src_address;
       switch (key0.protocol)
 	{
-	case SNAT_PROTOCOL_ICMP:
+	case NAT_PROTOCOL_ICMP:
 	  inner_icmp0 = (icmp46_header_t *) l4_header;
 	  inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 	  key0.port = inner_echo0->identifier;
 	  break;
-	case SNAT_PROTOCOL_UDP:
-	case SNAT_PROTOCOL_TCP:
+	case NAT_PROTOCOL_UDP:
+	case NAT_PROTOCOL_TCP:
 	  key0.port = ((tcp_udp_header_t *) l4_header)->src_port;
 	  break;
 	default:
@@ -624,7 +624,7 @@ icmp_out2in (snat_main_t * sm,
 
 	  switch (protocol)
 	    {
-	    case SNAT_PROTOCOL_ICMP:
+	    case NAT_PROTOCOL_ICMP:
 	      inner_icmp0 = (icmp46_header_t *) l4_header;
 	      inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 
@@ -638,8 +638,8 @@ icmp_out2in (snat_main_t * sm,
 				identifier);
 	      icmp0->checksum = ip_csum_fold (sum0);
 	      break;
-	    case SNAT_PROTOCOL_UDP:
-	    case SNAT_PROTOCOL_TCP:
+	    case NAT_PROTOCOL_UDP:
+	    case NAT_PROTOCOL_TCP:
 	      old_id0 = ((tcp_udp_header_t *) l4_header)->src_port;
 	      new_id0 = sm0.port;
 	      ((tcp_udp_header_t *) l4_header)->src_port = new_id0;
@@ -813,9 +813,9 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 	      goto trace0;
 	    }
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    {
 	      if (nat_out2in_sm_unknown_proto (sm, b0, ip0, rx_fib_index0))
 		{
@@ -830,7 +830,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 	      goto trace0;
 	    }
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      next0 = icmp_out2in_slow_path
 		(sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
@@ -859,7 +859,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 		   * be able to use dhcp client on the outside interface
 		   */
 		  if (PREDICT_FALSE
-		      (proto0 == SNAT_PROTOCOL_UDP
+		      (proto0 == NAT_PROTOCOL_UDP
 		       && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
 			   clib_host_to_net_u16
 			   (UDP_DST_PORT_dhcp_to_client))))
@@ -903,7 +903,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 				 dst_address /* changed member */ );
 	  ip0->checksum = ip_csum_fold (sum0);
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 		{
@@ -985,9 +985,9 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 	      goto trace1;
 	    }
 
-	  proto1 = ip_proto_to_snat_proto (ip1->protocol);
+	  proto1 = ip_proto_to_nat_proto (ip1->protocol);
 
-	  if (PREDICT_FALSE (proto1 == ~0))
+	  if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_OTHER))
 	    {
 	      if (nat_out2in_sm_unknown_proto (sm, b1, ip1, rx_fib_index1))
 		{
@@ -1002,7 +1002,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 	      goto trace1;
 	    }
 
-	  if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
 	    {
 	      next1 = icmp_out2in_slow_path
 		(sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
@@ -1031,7 +1031,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 		   * be able to use dhcp client on the outside interface
 		   */
 		  if (PREDICT_FALSE
-		      (proto1 == SNAT_PROTOCOL_UDP
+		      (proto1 == NAT_PROTOCOL_UDP
 		       && (vnet_buffer (b1)->ip.reass.l4_dst_port ==
 			   clib_host_to_net_u16
 			   (UDP_DST_PORT_dhcp_to_client))))
@@ -1077,7 +1077,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 				 dst_address /* changed member */ );
 	  ip1->checksum = ip_csum_fold (sum1);
 
-	  if (PREDICT_TRUE (proto1 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto1 == NAT_PROTOCOL_TCP))
 	    {
 	      if (!vnet_buffer (b1)->ip.reass.is_non_first_fragment)
 		{
@@ -1190,9 +1190,9 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 	  rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
 				   sw_if_index0);
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    {
 	      if (nat_out2in_sm_unknown_proto (sm, b0, ip0, rx_fib_index0))
 		{
@@ -1217,7 +1217,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 	      goto trace00;
 	    }
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      next0 = icmp_out2in_slow_path
 		(sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
@@ -1246,7 +1246,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 		   * be able to use dhcp client on the outside interface
 		   */
 		  if (PREDICT_FALSE
-		      (proto0 == SNAT_PROTOCOL_UDP
+		      (proto0 == NAT_PROTOCOL_UDP
 		       && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
 			   clib_host_to_net_u16
 			   (UDP_DST_PORT_dhcp_to_client))))
@@ -1292,7 +1292,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 				 dst_address /* changed member */ );
 	  ip0->checksum = ip_csum_fold (sum0);
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 		{
@@ -1472,12 +1472,12 @@ VLIB_NODE_FN (snat_out2in_fast_node) (vlib_main_t * vm,
 	      goto trace00;
 	    }
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    goto trace00;
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      next0 = icmp_out2in (sm, b0, ip0, icmp0, sw_if_index0,
 				   rx_fib_index0, node, next0, ~0, 0, 0);
@@ -1511,7 +1511,7 @@ VLIB_NODE_FN (snat_out2in_fast_node) (vlib_main_t * vm,
 	      old_port0 = udp0->dst_port;
 	      udp0->dst_port = new_port0;
 
-	      if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	      if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 		{
 		  sum0 = tcp0->checksum;
 		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
@@ -1536,7 +1536,7 @@ VLIB_NODE_FN (snat_out2in_fast_node) (vlib_main_t * vm,
 	    }
 	  else
 	    {
-	      if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	      if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 		{
 		  sum0 = tcp0->checksum;
 		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,