nat: optimize flow matching in ED NAT

This saves 6 clocks in nat44-ed-in2out node. (112->106 per packet)

Type: improvement
Signed-off-by: Klement Sekera <ksekera@cisco.com>
Change-Id: I48e757e7f4b6b0d250a432a4659fe6955fc52a07

1 files changed, 38 insertions, 31 deletions

diff --git a/src/plugins/nat/nat44-ed/nat44_ed_in2out.c b/src/plugins/nat/nat44-ed/nat44_ed_in2out.c
index 784dea0faf6..b99b3367329 100644
--- a/src/plugins/nat/nat44-ed/nat44_ed_in2out.c
+++ b/src/plugins/nat/nat44-ed/nat44_ed_in2out.c
@@ -918,10 +918,11 @@ nat44_ed_in2out_slowpath_unknown_proto (snat_main_t *sm, vlib_buffer_t *b,
 }
 
 static inline uword
-nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
-					  vlib_node_runtime_t * node,
-					  vlib_frame_t * frame,
-					  int is_output_feature)
+nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t *vm,
+					  vlib_node_runtime_t *node,
+					  vlib_frame_t *frame,
+					  int is_output_feature,
+					  int is_multi_worker)
 {
   u32 n_left_from, *from;
   snat_main_t *sm = &snat_main;
@@ -948,9 +949,7 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
       clib_bihash_kv_16_8_t kv0, value0;
       nat_translation_error_e translation_error = NAT_ED_TRNSL_ERR_SUCCESS;
       nat_6t_flow_t *f = 0;
-      ip4_address_t lookup_saddr, lookup_daddr;
-      u16 lookup_sport, lookup_dport;
-      u8 lookup_protocol;
+      nat_6t_t lookup;
       int lookup_skipped = 0;
 
       b0 = *b;
@@ -981,6 +980,7 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
       rx_fib_index0 =
 	fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4, sw_if_index0);
+      lookup.fib_index = rx_fib_index0;
 
       if (PREDICT_FALSE (ip0->ttl == 1))
 	{
@@ -1016,8 +1016,8 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 	      goto trace0;
 	    }
 	  int err = nat_get_icmp_session_lookup_values (
-	    b0, ip0, &lookup_saddr, &lookup_sport, &lookup_daddr,
-	    &lookup_dport, &lookup_protocol);
+	    b0, ip0, &lookup.saddr, &lookup.sport, &lookup.daddr,
+	    &lookup.dport, &lookup.proto);
 	  if (err != 0)
 	    {
 	      b0->error = node->errors[err];
@@ -1027,30 +1027,27 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 	}
       else
 	{
-	  lookup_protocol = ip0->protocol;
-	  lookup_saddr = ip0->src_address;
-	  lookup_daddr = ip0->dst_address;
-	  lookup_sport = vnet_buffer (b0)->ip.reass.l4_src_port;
-	  lookup_dport = vnet_buffer (b0)->ip.reass.l4_dst_port;
+	  lookup.proto = ip0->protocol;
+	  lookup.saddr.as_u32 = ip0->src_address.as_u32;
+	  lookup.daddr.as_u32 = ip0->dst_address.as_u32;
+	  lookup.sport = vnet_buffer (b0)->ip.reass.l4_src_port;
+	  lookup.dport = vnet_buffer (b0)->ip.reass.l4_dst_port;
 	}
 
       /* there might be a stashed index in vnet_buffer2 from handoff or
        * classify node, see if it can be used */
-      if (!pool_is_free_index (tsm->sessions,
+      if (is_multi_worker &&
+	  !pool_is_free_index (tsm->sessions,
 			       vnet_buffer2 (b0)->nat.cached_session_index))
 	{
 	  s0 = pool_elt_at_index (tsm->sessions,
 				  vnet_buffer2 (b0)->nat.cached_session_index);
 	  if (PREDICT_TRUE (
-		nat_6t_flow_match (&s0->i2o, b0, lookup_saddr, lookup_sport,
-				   lookup_daddr, lookup_dport, lookup_protocol,
-				   rx_fib_index0)
+		nat_6t_t_eq (&s0->i2o.match, &lookup)
 		// for some hairpinning cases there are two "i2i" flows instead
 		// of i2o and o2i as both hosts are on inside
 		|| (s0->flags & SNAT_SESSION_FLAG_HAIRPINNING &&
-		    nat_6t_flow_match (
-		      &s0->o2i, b0, lookup_saddr, lookup_sport, lookup_daddr,
-		      lookup_dport, lookup_protocol, rx_fib_index0))))
+		    nat_6t_t_eq (&s0->o2i.match, &lookup))))
 	    {
 	      /* yes, this is the droid we're looking for */
 	      lookup_skipped = 1;
@@ -1059,8 +1056,8 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 	  s0 = NULL;
 	}
 
-      init_ed_k (&kv0, ip0->src_address, lookup_sport, ip0->dst_address,
-		 lookup_dport, rx_fib_index0, lookup_protocol);
+      init_ed_k (&kv0, lookup.saddr, lookup.sport, lookup.daddr, lookup.dport,
+		 lookup.fib_index, lookup.proto);
 
       // lookup flow
       if (clib_bihash_search_16_8 (&sm->flow_hash, &kv0, &value0))
@@ -1117,16 +1114,12 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 
       b0->flags |= VNET_BUFFER_F_IS_NATED;
 
-      if (nat_6t_flow_match (&s0->i2o, b0, lookup_saddr, lookup_sport,
-			     lookup_daddr, lookup_dport, lookup_protocol,
-			     rx_fib_index0))
+      if (nat_6t_t_eq (&s0->i2o.match, &lookup))
 	{
 	  f = &s0->i2o;
 	}
       else if (s0->flags & SNAT_SESSION_FLAG_HAIRPINNING &&
-	       nat_6t_flow_match (&s0->o2i, b0, lookup_saddr, lookup_sport,
-				  lookup_daddr, lookup_dport, lookup_protocol,
-				  rx_fib_index0))
+	       nat_6t_t_eq (&s0->o2i.match, &lookup))
 	{
 	  f = &s0->o2i;
 	}
@@ -1459,7 +1452,14 @@ VLIB_NODE_FN (nat44_ed_in2out_node) (vlib_main_t * vm,
 				     vlib_node_runtime_t * node,
 				     vlib_frame_t * frame)
 {
-  return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 0);
+  if (snat_main.num_workers > 1)
+    {
+      return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 0, 1);
+    }
+  else
+    {
+      return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 0, 0);
+    }
 }
 
 VLIB_REGISTER_NODE (nat44_ed_in2out_node) = {
@@ -1477,7 +1477,14 @@ VLIB_NODE_FN (nat44_ed_in2out_output_node) (vlib_main_t * vm,
 					    vlib_node_runtime_t * node,
 					    vlib_frame_t * frame)
 {
-  return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 1);
+  if (snat_main.num_workers > 1)
+    {
+      return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 1, 1);
+    }
+  else
+    {
+      return nat44_ed_in2out_fast_path_node_fn_inline (vm, node, frame, 1, 0);
+    }
 }
 
 VLIB_REGISTER_NODE (nat44_ed_in2out_output_node) = {