bfd: add per session counters

Add udp total session counts - as stat segment entries:

/bfd/udp4/sessions
/bfd/udp6/sessions

and per session packet/byte counters:

/bfd/rx-session-counters
/bfd/rx-session-echo-counters
/bfd/tx-session-counters
/bfd/tx-session-echo-counters

These counters are per-thread and per-session id.

Adjust tests to verify proper function.

Type: refactor
Signed-off-by: Klement Sekera <klement.sekera@gmail.com>
Change-Id: Ie597928022b6ac74c2220019b9e8e1714295f170
diff --git a/src/vnet/bfd/bfd_main.c b/src/vnet/bfd/bfd_main.c
index 23e3f0f..a9dd60e 100644
--- a/src/vnet/bfd/bfd_main.c
+++ b/src/vnet/bfd/bfd_main.c
@@ -30,6 +30,17 @@
 #include <vlib/log.h>
 #include <vnet/crypto/crypto.h>
 
+static void
+bfd_validate_counters (bfd_main_t *bm)
+{
+  vlib_validate_combined_counter (&bm->rx_counter, pool_elts (bm->sessions));
+  vlib_validate_combined_counter (&bm->rx_echo_counter,
+				  pool_elts (bm->sessions));
+  vlib_validate_combined_counter (&bm->tx_counter, pool_elts (bm->sessions));
+  vlib_validate_combined_counter (&bm->tx_echo_counter,
+				  pool_elts (bm->sessions));
+}
+
 static u64
 bfd_calc_echo_checksum (u32 discriminator, u64 expire_time, u32 secret)
 {
@@ -727,11 +738,11 @@
     {
     case BFD_TRANSPORT_UDP4:
       BFD_DBG ("Transport bfd via udp4, bs_idx=%u", bs->bs_idx);
-      return bfd_transport_udp4 (vm, bi, bs);
+      return bfd_transport_udp4 (vm, bi, bs, 0 /* is_echo */);
       break;
     case BFD_TRANSPORT_UDP6:
       BFD_DBG ("Transport bfd via udp6, bs_idx=%u", bs->bs_idx);
-      return bfd_transport_udp6 (vm, bi, bs);
+      return bfd_transport_udp6 (vm, bi, bs, 0 /* is_echo */);
       break;
     }
   return 0;
@@ -761,11 +772,11 @@
     {
     case BFD_TRANSPORT_UDP4:
       BFD_DBG ("Transport bfd echo via udp4, bs_idx=%u", bs->bs_idx);
-      return bfd_transport_udp4 (vm, bi, bs);
+      return bfd_transport_udp4 (vm, bi, bs, 1 /* is_echo */);
       break;
     case BFD_TRANSPORT_UDP6:
       BFD_DBG ("Transport bfd echo via udp6, bs_idx=%u", bs->bs_idx);
-      return bfd_transport_udp6 (vm, bi, bs);
+      return bfd_transport_udp6 (vm, bi, bs, 1 /* is_echo */);
       break;
     }
   return 0;
@@ -1336,6 +1347,14 @@
   bm->owner_thread_index = ~0;
   if (n_vlib_mains > 1)
     clib_spinlock_init (&bm->lock);
+  bm->rx_counter.name = "bfd rx session counters";
+  bm->rx_counter.stat_segment_name = "/bfd/rx-session-counters";
+  bm->rx_echo_counter.name = "bfd rx session echo counters";
+  bm->rx_echo_counter.stat_segment_name = "/bfd/rx-session-echo-counters";
+  bm->tx_counter.name = "bfd tx session counters";
+  bm->tx_counter.stat_segment_name = "/bfd/tx-session-counters";
+  bm->tx_echo_counter.name = "bfd tx session echo counters";
+  bm->tx_echo_counter.stat_segment_name = "/bfd/tx-session-echo-counters";
   return 0;
 }
 
@@ -1371,6 +1390,11 @@
   while (hash_get (bm->session_by_disc, result->local_discr));
   bfd_set_defaults (bm, result);
   hash_set (bm->session_by_disc, result->local_discr, result->bs_idx);
+  bfd_validate_counters (bm);
+  vlib_zero_combined_counter (&bm->rx_counter, result->bs_idx);
+  vlib_zero_combined_counter (&bm->rx_echo_counter, result->bs_idx);
+  vlib_zero_combined_counter (&bm->tx_counter, result->bs_idx);
+  vlib_zero_combined_counter (&bm->tx_echo_counter, result->bs_idx);
   bfd_unlock (bm);
   return result;
 }
@@ -1392,6 +1416,10 @@
       --bs->auth.next_key->use_count;
     }
   hash_unset (bm->session_by_disc, bs->local_discr);
+  vlib_zero_combined_counter (&bm->rx_counter, bs->bs_idx);
+  vlib_zero_combined_counter (&bm->rx_echo_counter, bs->bs_idx);
+  vlib_zero_combined_counter (&bm->tx_counter, bs->bs_idx);
+  vlib_zero_combined_counter (&bm->tx_echo_counter, bs->bs_idx);
   pool_put (bm->sessions, bs);
   bfd_unlock (bm);
 }
@@ -1905,8 +1933,8 @@
     }
 }
 
-int
-bfd_consume_echo_pkt (vlib_main_t * vm, bfd_main_t * bm, vlib_buffer_t * b)
+bfd_session_t *
+bfd_consume_echo_pkt (vlib_main_t *vm, bfd_main_t *bm, vlib_buffer_t *b)
 {
   bfd_echo_pkt_t *pkt = NULL;
   if (b->current_length != sizeof (*pkt))
@@ -1926,7 +1954,7 @@
   if (checksum != pkt->checksum)
     {
       BFD_DBG ("Invalid echo packet, checksum mismatch");
-      return 1;
+      return 0;
     }
   u64 now = bfd_time_now_nsec (vm, NULL);
   if (pkt->expire_time_nsec < now)
@@ -1938,7 +1966,7 @@
     {
       bs->echo_last_rx_nsec = now;
     }
-  return 1;
+  return bs;
 }
 
 u8 *
diff --git a/src/vnet/bfd/bfd_main.h b/src/vnet/bfd/bfd_main.h
index 5e9f025..2d91e68 100644
--- a/src/vnet/bfd/bfd_main.h
+++ b/src/vnet/bfd/bfd_main.h
@@ -258,7 +258,7 @@
 } bfd_listen_event_e;
 
 /**
- * session nitification call back function type
+ * session notification call back function type
  */
 typedef void (*bfd_notify_fn_t) (bfd_listen_event_e, const bfd_session_t *);
 
@@ -322,6 +322,11 @@
   vlib_log_class_t log_class;
 
   u16 msg_id_base;
+
+  vlib_combined_counter_main_t rx_counter;
+  vlib_combined_counter_main_t rx_echo_counter;
+  vlib_combined_counter_main_t tx_counter;
+  vlib_combined_counter_main_t tx_echo_counter;
 } bfd_main_t;
 
 extern bfd_main_t bfd_main;
@@ -412,10 +417,11 @@
 bfd_session_t *bfd_find_session_by_idx (bfd_main_t * bm, uword bs_idx);
 bfd_session_t *bfd_find_session_by_disc (bfd_main_t * bm, u32 disc);
 void bfd_session_start (bfd_main_t * bm, bfd_session_t * bs);
+void bfd_session_stop (bfd_main_t *bm, bfd_session_t *bs);
 void bfd_consume_pkt (vlib_main_t * vm, bfd_main_t * bm,
 		      const bfd_pkt_t * bfd, u32 bs_idx);
-int bfd_consume_echo_pkt (vlib_main_t * vm, bfd_main_t * bm,
-			  vlib_buffer_t * b);
+bfd_session_t *bfd_consume_echo_pkt (vlib_main_t *vm, bfd_main_t *bm,
+				     vlib_buffer_t *b);
 int bfd_verify_pkt_common (const bfd_pkt_t * pkt);
 int bfd_verify_pkt_auth (vlib_main_t * vm, const bfd_pkt_t * pkt,
 			 u16 pkt_size, bfd_session_t * bs);
diff --git a/src/vnet/bfd/bfd_udp.c b/src/vnet/bfd/bfd_udp.c
index d8fd4a1..97b1a73 100644
--- a/src/vnet/bfd/bfd_udp.c
+++ b/src/vnet/bfd/bfd_udp.c
@@ -35,6 +35,7 @@
 #include <vnet/dpo/receive_dpo.h>
 #include <vnet/fib/fib_entry.h>
 #include <vnet/fib/fib_table.h>
+#include <vpp/stats/stat_segment.h>
 #include <vnet/bfd/bfd_debug.h>
 #include <vnet/bfd/bfd_udp.h>
 #include <vnet/bfd/bfd_main.h>
@@ -68,8 +69,10 @@
   vlib_log_class_t log_class;
   /* number of active udp4 sessions */
   u32 udp4_sessions_count;
+  u32 udp4_sessions_count_stat_seg_entry;
   /* number of active udp6 sessions */
   u32 udp6_sessions_count;
+  u32 udp6_sessions_count_stat_seg_entry;
 } bfd_udp_main_t;
 
 static vlib_node_registration_t bfd_udp4_input_node;
@@ -79,6 +82,14 @@
 
 bfd_udp_main_t bfd_udp_main;
 
+void
+bfd_udp_update_stat_segment_entry (u32 entry, u64 value)
+{
+  vlib_stat_segment_lock ();
+  stat_segment_set_state_counter (entry, value);
+  vlib_stat_segment_unlock ();
+}
+
 vnet_api_error_t
 bfd_udp_set_echo_source (u32 sw_if_index)
 {
@@ -94,7 +105,7 @@
 }
 
 vnet_api_error_t
-bfd_udp_del_echo_source (u32 sw_if_index)
+bfd_udp_del_echo_source ()
 {
   bfd_udp_main.echo_source_sw_if_index = ~0;
   bfd_udp_main.echo_source_is_set = 0;
@@ -372,13 +383,18 @@
 }
 
 static void
-bfd_create_frame_to_next_node (vlib_main_t * vm, u32 bi, u32 next_node)
+bfd_create_frame_to_next_node (vlib_main_t *vm, bfd_main_t *bm,
+			       const bfd_session_t *bs, u32 bi, u32 next_node,
+			       vlib_combined_counter_main_t *tx_counter)
 {
   vlib_frame_t *f = vlib_get_frame_to_node (vm, next_node);
   u32 *to_next = vlib_frame_vector_args (f);
   to_next[0] = bi;
   f->n_vectors = 1;
   vlib_put_frame_to_node (vm, next_node, f);
+  vlib_buffer_t *b = vlib_get_buffer (vm, bi);
+  vlib_increment_combined_counter (tx_counter, vm->thread_index, bs->bs_idx, 1,
+				   vlib_buffer_length_in_chain (vm, b));
 }
 
 int
@@ -435,25 +451,33 @@
 }
 
 int
-bfd_transport_udp4 (vlib_main_t * vm, u32 bi, const struct bfd_session_s *bs)
+bfd_transport_udp4 (vlib_main_t *vm, u32 bi, const struct bfd_session_s *bs,
+		    int is_echo)
 {
   u32 next_node;
   int rv = bfd_udp_calc_next_node (bs, &next_node);
+  bfd_main_t *bm = bfd_udp_main.bfd_main;
   if (rv)
     {
-      bfd_create_frame_to_next_node (vm, bi, next_node);
+      bfd_create_frame_to_next_node (vm, bm, bs, bi, next_node,
+				     is_echo ? &bm->tx_echo_counter :
+					       &bm->tx_counter);
     }
   return rv;
 }
 
 int
-bfd_transport_udp6 (vlib_main_t * vm, u32 bi, const struct bfd_session_s *bs)
+bfd_transport_udp6 (vlib_main_t *vm, u32 bi, const struct bfd_session_s *bs,
+		    int is_echo)
 {
   u32 next_node;
   int rv = bfd_udp_calc_next_node (bs, &next_node);
+  bfd_main_t *bm = bfd_udp_main.bfd_main;
   if (rv)
     {
-      bfd_create_frame_to_next_node (vm, bi, next_node);
+      bfd_create_frame_to_next_node (
+	vm, bfd_udp_main.bfd_main, bs, bi, next_node,
+	is_echo ? &bm->tx_echo_counter : &bm->tx_counter);
     }
   return 1;
 }
@@ -530,6 +554,8 @@
 	       "returns %d", format_ip46_address, &key->peer_addr,
 	       IP46_TYPE_ANY, key->sw_if_index, bus->adj_index);
       ++bum->udp4_sessions_count;
+      bfd_udp_update_stat_segment_entry (
+	bum->udp4_sessions_count_stat_seg_entry, bum->udp4_sessions_count);
       if (1 == bum->udp4_sessions_count)
 	{
 	  udp_register_dst_port (vm, UDP_DST_PORT_bfd4,
@@ -547,6 +573,8 @@
 	       "returns %d", format_ip46_address, &key->peer_addr,
 	       IP46_TYPE_ANY, key->sw_if_index, bus->adj_index);
       ++bum->udp6_sessions_count;
+      bfd_udp_update_stat_segment_entry (
+	bum->udp6_sessions_count_stat_seg_entry, bum->udp6_sessions_count);
       if (1 == bum->udp6_sessions_count)
 	{
 	  udp_register_dst_port (vm, UDP_DST_PORT_bfd6,
@@ -719,6 +747,8 @@
     {
     case BFD_TRANSPORT_UDP4:
       --bum->udp4_sessions_count;
+      bfd_udp_update_stat_segment_entry (
+	bum->udp4_sessions_count_stat_seg_entry, bum->udp4_sessions_count);
       if (!bum->udp4_sessions_count)
 	{
 	  udp_unregister_dst_port (vm, UDP_DST_PORT_bfd4, 1);
@@ -727,6 +757,8 @@
       break;
     case BFD_TRANSPORT_UDP6:
       --bum->udp6_sessions_count;
+      bfd_udp_update_stat_segment_entry (
+	bum->udp6_sessions_count_stat_seg_entry, bum->udp6_sessions_count);
       if (!bum->udp6_sessions_count)
 	{
 	  udp_unregister_dst_port (vm, UDP_DST_PORT_bfd6, 0);
@@ -1342,6 +1374,9 @@
       next0 = BFD_UDP_INPUT_NEXT_NORMAL;
       if (BFD_UDP_ERROR_NONE == error0)
 	{
+	  vlib_increment_combined_counter (
+	    &bm->rx_counter, vm->thread_index, bs->bs_idx, 1,
+	    vlib_buffer_length_in_chain (vm, b0));
 	  /*
 	   *  if everything went fine, check for poll bit, if present, re-use
 	   *  the buffer and based on (now updated) session parameters, send
@@ -1488,8 +1523,9 @@
 	  clib_memcpy_fast (t0->data, vlib_buffer_get_current (b0), len);
 	}
 
+      bfd_session_t *bs = NULL;
       bfd_lock (bm);
-      if (bfd_consume_echo_pkt (vm, bfd_udp_main.bfd_main, b0))
+      if ((bs = bfd_consume_echo_pkt (vm, bfd_udp_main.bfd_main, b0)))
 	{
 	  b0->error = rt->errors[BFD_UDP_ERROR_NONE];
 	  next0 = BFD_UDP_ECHO_INPUT_NEXT_NORMAL;
@@ -1512,6 +1548,14 @@
 	}
 
       bfd_unlock (bm);
+
+      if (bs)
+	{
+	  vlib_increment_combined_counter (
+	    &bm->rx_echo_counter, vm->thread_index, bs->bs_idx, 1,
+	    vlib_buffer_length_in_chain (vm, b0));
+	}
+
       vlib_set_next_frame_buffer (vm, rt, next0, bi0);
 
       from += 1;
@@ -1640,6 +1684,32 @@
 
 VNET_SW_INTERFACE_ADD_DEL_FUNCTION (bfd_udp_sw_if_add_del);
 
+clib_error_t *
+bfd_udp_stats_init (bfd_udp_main_t *bum)
+{
+  const char *name4 = "/bfd/udp4/sessions";
+  bum->udp4_sessions_count_stat_seg_entry =
+    stat_segment_new_entry ((u8 *) name4, STAT_DIR_TYPE_SCALAR_INDEX);
+
+  stat_segment_set_state_counter (bum->udp4_sessions_count_stat_seg_entry, 0);
+  if (~0 == bum->udp4_sessions_count_stat_seg_entry)
+    {
+      return clib_error_return (
+	0, "Could not create stat segment entry for %s", name4);
+    }
+  const char *name6 = "/bfd/udp6/sessions";
+  bum->udp6_sessions_count_stat_seg_entry =
+    stat_segment_new_entry ((u8 *) name6, STAT_DIR_TYPE_SCALAR_INDEX);
+
+  if (~0 == bum->udp6_sessions_count_stat_seg_entry)
+    {
+      return clib_error_return (
+	0, "Could not create stat segment entry for %s", name6);
+    }
+
+  return 0;
+}
+
 /*
  * setup function
  */
@@ -1671,6 +1741,8 @@
   ASSERT (node);
   bfd_udp_main.ip6_midchain_idx = node->index;
 
+  bfd_udp_stats_init (&bfd_udp_main);
+
   bfd_udp_main.log_class = vlib_log_register_class ("bfd", "udp");
   vlib_log_debug (bfd_udp_main.log_class, "initialized");
   return 0;
diff --git a/src/vnet/bfd/bfd_udp.h b/src/vnet/bfd/bfd_udp.h
index 8786810..866b586 100644
--- a/src/vnet/bfd/bfd_udp.h
+++ b/src/vnet/bfd/bfd_udp.h
@@ -24,7 +24,6 @@
 #include <vnet/ip/ip6_packet.h>
 #include <vnet/bfd/bfd_api.h>
 
-/* *INDENT-OFF* */
 /** identifier of BFD session based on UDP transport only */
 typedef CLIB_PACKED (struct {
   union {
@@ -38,7 +37,6 @@
   /** peer address */
   ip46_address_t peer_addr;
 }) bfd_udp_key_t;
-/* *INDENT-ON* */
 
 /** UDP transport specific data embedded in bfd_session's union */
 typedef struct
@@ -82,22 +80,18 @@
 /**
  * @brief transport packet over udpv4
  *
- * @param is_echo 1 if this is echo packet, 0 if control frame
- *
  * @return 1 on success, 0 on failure
  */
-int bfd_transport_udp4 (vlib_main_t * vm, u32 bi,
-			const struct bfd_session_s *bs);
+int bfd_transport_udp4 (vlib_main_t *vm, u32 bi,
+			const struct bfd_session_s *bs, int is_echo);
 
 /**
  * @brief transport packet over udpv6
  *
- * @param is_echo 1 if this is echo packet, 0 if control frame
- *
  * @return 1 on success, 0 on failure
  */
-int bfd_transport_udp6 (vlib_main_t * vm, u32 bi,
-			const struct bfd_session_s *bs);
+int bfd_transport_udp6 (vlib_main_t *vm, u32 bi,
+			const struct bfd_session_s *bs, int is_echo);
 
 /**
  * @brief check if the bfd udp layer is echo-capable at this time