nat: fix LRU blocked by inactive session

This fixes a situation where long-lived inactive session blocks LRU
list. Solution is to have multiple LRU lists based on session type.
This helps because session timeout is same for all sessions of same
type.

Type: fix

Signed-off-by: Klement Sekera <ksekera@cisco.com>
Change-Id: I5e54b2aab73b23911d6518d42e8c3f166c69a38c

1 files changed, 13 insertions, 12 deletions

diff --git a/src/plugins/nat/in2out_ed.c b/src/plugins/nat/in2out_ed.c
index f8682d0f3c2..45d9fd0b32c 100644
--- a/src/plugins/nat/in2out_ed.c
+++ b/src/plugins/nat/in2out_ed.c
@@ -31,6 +31,7 @@
 #include <nat/nat44/inlines.h>
 #include <nat/nat_syslog.h>
 #include <nat/nat_ha.h>
+#include <nat/nat44/ed_inlines.h>
 
 static char *nat_in2out_ed_error_strings[] = {
 #define _(sym,string) string,
@@ -155,7 +156,7 @@ nat44_i2o_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
       snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 					  &s->out2in);
     delete:
-      nat44_ed_delete_session (sm, s, ctx->thread_index, 1);
+      nat_ed_session_delete (sm, s, ctx->thread_index, 1);
       return 1;
     }
 
@@ -323,7 +324,7 @@ slow_path_ed (snat_main_t * sm,
   if (PREDICT_FALSE
       (nat44_ed_maximum_sessions_exceeded (sm, rx_fib_index, thread_index)))
     {
-      if (!nat_global_lru_free_one (sm, thread_index, now))
+      if (!nat_lru_free_one (sm, thread_index, now))
 	{
 	  b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 	  nat_ipfix_logging_max_sessions (thread_index, sm->max_translations);
@@ -342,7 +343,7 @@ slow_path_ed (snat_main_t * sm,
   if (snat_static_mapping_match
       (sm, key0, &key1, 0, 0, 0, &lb, 0, &identity_nat))
     {
-      s = nat_ed_session_alloc (sm, thread_index, now);
+      s = nat_ed_session_alloc (sm, thread_index, now, proto);
       if (!s)
 	{
 	  nat_elog_warn ("create NAT session failed");
@@ -386,7 +387,7 @@ slow_path_ed (snat_main_t * sm,
 	  nat_elog_notice ("addresses exhausted");
 	  b->error = node->errors[NAT_IN2OUT_ED_ERROR_OUT_OF_PORTS];
 	  nat_free_session_data (sm, s, thread_index, 0);
-	  nat44_ed_delete_session (sm, s, thread_index, 1);
+	  nat_ed_session_delete (sm, s, thread_index, 1);
 	  return NAT_NEXT_DROP;
 	}
       key1.addr = allocated_addr;
@@ -399,7 +400,7 @@ slow_path_ed (snat_main_t * sm,
 	  *sessionp = s;
 	  return next;
 	}
-      s = nat_ed_session_alloc (sm, thread_index, now);
+      s = nat_ed_session_alloc (sm, thread_index, now, proto);
       if (!s)
 	{
 	  nat_elog_warn ("create NAT session failed");
@@ -601,7 +602,7 @@ nat44_ed_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip,
       if (nat44_is_ses_closed (s))
 	{
 	  nat_free_session_data (sm, s, thread_index, 0);
-	  nat44_ed_delete_session (sm, s, thread_index, 1);
+	  nat_ed_session_delete (sm, s, thread_index, 1);
 	}
       else
 	s->flags |= SNAT_SESSION_FLAG_OUTPUT_FEATURE;
@@ -857,7 +858,7 @@ nat44_ed_in2out_unknown_proto (snat_main_t * sm,
 	}
 
     create_ses:
-      s = nat_ed_session_alloc (sm, thread_index, now);
+      s = nat_ed_session_alloc (sm, thread_index, now, ip->protocol);
       if (!s)
 	{
 	  b->error = node->errors[NAT_IN2OUT_ED_ERROR_MAX_USER_SESS_EXCEEDED];
@@ -1026,9 +1027,9 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 	    }
 	  s0 = pool_elt_at_index (tsm->sessions, value0.value);
 
-	  if (s0->tcp_close_timestamp)
+	  if (s0->tcp_closed_timestamp)
 	    {
-	      if (now >= s0->tcp_close_timestamp)
+	      if (now >= s0->tcp_closed_timestamp)
 		{
 		  // session is closed, go slow path
 		  next0 = def_slow;
@@ -1049,7 +1050,7 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 	  if (now >= sess_timeout_time)
 	    {
 	      nat_free_session_data (sm, s0, thread_index, 0);
-	      nat44_ed_delete_session (sm, s0, thread_index, 1);
+	      nat_ed_session_delete (sm, s0, thread_index, 1);
 	      // session is closed, go slow path
 	      next0 = def_slow;
 	      goto trace0;
@@ -1307,10 +1308,10 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t * vm,
 	    {
 	      s0 = pool_elt_at_index (tsm->sessions, value0.value);
 
-	      if (s0->tcp_close_timestamp && now >= s0->tcp_close_timestamp)
+	      if (s0->tcp_closed_timestamp && now >= s0->tcp_closed_timestamp)
 		{
 		  nat_free_session_data (sm, s0, thread_index, 0);
-		  nat44_ed_delete_session (sm, s0, thread_index, 1);
+		  nat_ed_session_delete (sm, s0, thread_index, 1);
 		  s0 = NULL;
 		}
 	    }