bgpd: add basic packet-related tracepoints

Add tracepoints for:
- packet pushed to internal rx queue
- packet dequeued from rx queue and processed

Signed-off-by: Quentin Young <qlyoung@nvidia.com>

bgpd/bgp_io.c

@@ -39,6 +39,7 @@
 #include "bgpd/bgp_errors.h"	// for expanded error reference information
 #include "bgpd/bgp_fsm.h"	// for BGP_EVENT_ADD, bgp_event
 #include "bgpd/bgp_packet.h"	// for bgp_notify_send_with_data, bgp_notify...
+#include "bgpd/bgp_trace.h"	// for tracepoints
 #include "bgpd/bgpd.h"		// for peer, BGP_MARKER_SIZE, bgp_master, bm
 /* clang-format on */
 
@@ -235,6 +236,7 @@ static int bgp_process_reads(struct thread *thread)
 			stream_set_endp(pkt, pktsize);
 
 			frr_with_mutex(&peer->io_mtx) {
+				tracepoint(frr_bgp, packet_read, peer, pkt);
 				stream_fifo_push(peer->ibuf, pkt);
 			}
 

bgpd/bgp_packet.c

@@ -63,6 +63,7 @@
 #include "bgpd/bgp_io.h"
 #include "bgpd/bgp_keepalives.h"
 #include "bgpd/bgp_flowspec.h"
+#include "bgpd/bgp_trace.h"
 
 DEFINE_HOOK(bgp_packet_dump,
 		(struct peer *peer, uint8_t type, bgp_size_t size,
@@ -2366,6 +2367,7 @@ int bgp_process_packet(struct thread *thread)
 		 */
 		switch (type) {
 		case BGP_MSG_OPEN:
+			tracepoint(frr_bgp, open_process, peer, size);
 			atomic_fetch_add_explicit(&peer->open_in, 1,
 						  memory_order_relaxed);
 			mprc = bgp_open_receive(peer, size);
@@ -2376,6 +2378,7 @@ int bgp_process_packet(struct thread *thread)
 					__func__, peer->host);
 			break;
 		case BGP_MSG_UPDATE:
+			tracepoint(frr_bgp, update_process, peer, size);
 			atomic_fetch_add_explicit(&peer->update_in, 1,
 						  memory_order_relaxed);
 			peer->readtime = monotime(NULL);
@@ -2387,6 +2390,7 @@ int bgp_process_packet(struct thread *thread)
 					__func__, peer->host);
 			break;
 		case BGP_MSG_NOTIFY:
+			tracepoint(frr_bgp, notification_process, peer, size);
 			atomic_fetch_add_explicit(&peer->notify_in, 1,
 						  memory_order_relaxed);
 			mprc = bgp_notify_receive(peer, size);
@@ -2397,6 +2401,7 @@ int bgp_process_packet(struct thread *thread)
 					__func__, peer->host);
 			break;
 		case BGP_MSG_KEEPALIVE:
+			tracepoint(frr_bgp, keepalive_process, peer, size);
 			peer->readtime = monotime(NULL);
 			atomic_fetch_add_explicit(&peer->keepalive_in, 1,
 						  memory_order_relaxed);
@@ -2409,6 +2414,7 @@ int bgp_process_packet(struct thread *thread)
 			break;
 		case BGP_MSG_ROUTE_REFRESH_NEW:
 		case BGP_MSG_ROUTE_REFRESH_OLD:
+			tracepoint(frr_bgp, refresh_process, peer, size);
 			atomic_fetch_add_explicit(&peer->refresh_in, 1,
 						  memory_order_relaxed);
 			mprc = bgp_route_refresh_receive(peer, size);
@@ -2419,6 +2425,7 @@ int bgp_process_packet(struct thread *thread)
 					__func__, peer->host);
 			break;
 		case BGP_MSG_CAPABILITY:
+			tracepoint(frr_bgp, capability_process, peer, size);
 			atomic_fetch_add_explicit(&peer->dynamic_cap_in, 1,
 						  memory_order_relaxed);
 			mprc = bgp_capability_receive(peer, size);

bgpd/bgp_trace.c

@@ -0,0 +1,4 @@
+#define TRACEPOINT_CREATE_PROBES
+#define TRACEPOINT_DEFINE
+
+#include "bgp_trace.h"

bgpd/bgp_trace.h

@@ -0,0 +1,88 @@
+/* Tracing for BGP
+ *
+ * Copyright (C) 2020  NVIDIA Corporation
+ * Quentin Young
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; see the file COPYING; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#if !defined(_BGP_TRACE_H) || defined(TRACEPOINT_HEADER_MULTI_READ)
+#define _BGP_TRACE_H
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#ifdef HAVE_LTTNG
+
+#undef TRACEPOINT_PROVIDER
+#define TRACEPOINT_PROVIDER frr_bgp
+
+#undef TRACEPOINT_INCLUDE
+#define TRACEPOINT_INCLUDE "bgpd/bgp_trace.h"
+
+#include <lttng/tracepoint.h>
+
+#include "bgpd/bgpd.h"
+#include "lib/stream.h"
+
+/* clang-format off */
+
+TRACEPOINT_EVENT_CLASS(
+	frr_bgp,
+	packet_process,
+	TP_ARGS(struct peer *, peer, bgp_size_t, size),
+	TP_FIELDS(
+		ctf_string(peer, peer->host ? peer->host : "(unknown peer)")
+	)
+)
+
+#define PKT_PROCESS_TRACEPOINT_INSTANCE(name)                                  \
+	TRACEPOINT_EVENT_INSTANCE(                                             \
+		frr_bgp, packet_process, name,                                 \
+		TP_ARGS(struct peer *, peer, bgp_size_t, size))                \
+	TRACEPOINT_LOGLEVEL(frr_bgp, name, TRACE_INFO)
+
+PKT_PROCESS_TRACEPOINT_INSTANCE(open_process)
+PKT_PROCESS_TRACEPOINT_INSTANCE(keepalive_process)
+PKT_PROCESS_TRACEPOINT_INSTANCE(update_process)
+PKT_PROCESS_TRACEPOINT_INSTANCE(notification_process)
+PKT_PROCESS_TRACEPOINT_INSTANCE(capability_process)
+PKT_PROCESS_TRACEPOINT_INSTANCE(refresh_process)
+
+TRACEPOINT_EVENT(
+	frr_bgp,
+	packet_read,
+	TP_ARGS(struct peer *, peer, struct stream *, pkt),
+	TP_FIELDS(
+		ctf_string(peer, peer->host ? peer->host : "(unknown peer)")
+		ctf_integer(size_t, size, STREAM_READABLE(pkt))
+		ctf_sequence_hex(uint8_t, packet, pkt->data, size_t, STREAM_READABLE(pkt))
+	)
+)
+
+
+#include <lttng/tracepoint-event.h>
+
+#else /* HAVE_LTTNG */
+
+#define tracepoint(...)
+#define tracef(...)
+#define tracelog(...)
+#define tracepoint_enabled(...) true
+
+#endif /* HAVE_LTTNG */
+
+#endif /* _BGP_TRACE_H */

bgpd/subdir.am

@@ -104,6 +104,7 @@ bgpd_libbgp_a_SOURCES = \
 	bgpd/bgpd.c \
 	bgpd/bgp_nb.c \
 	bgpd/bgp_nb_config.c \
+	bgpd/bgp_trace.c \
 	# end
 
 if ENABLE_BGP_VNC
@@ -178,6 +179,7 @@ noinst_HEADERS += \
 	bgpd/bgp_zebra.h \
 	bgpd/bgpd.h \
 	bgpd/bgp_nb.h \
+	bgpd/bgp_trace.h \
 	\
 	bgpd/rfapi/bgp_rfapi_cfg.h \
 	bgpd/rfapi/rfapi_import.h \
@@ -208,8 +210,8 @@ bgpd_bgpd_CFLAGS = $(AM_CFLAGS)
 bgpd_bgp_btoa_CFLAGS = $(AM_CFLAGS)
 
 # RFPLDADD is set in bgpd/rfp-example/librfp/subdir.am
-bgpd_bgpd_LDADD = bgpd/libbgp.a $(RFPLDADD) lib/libfrr.la $(LIBCAP) $(LIBM)
+bgpd_bgpd_LDADD = bgpd/libbgp.a $(RFPLDADD) lib/libfrr.la $(LIBCAP) $(LIBM) $(UST_LIBS)
-bgpd_bgp_btoa_LDADD = bgpd/libbgp.a $(RFPLDADD) lib/libfrr.la $(LIBCAP) $(LIBM)
+bgpd_bgp_btoa_LDADD = bgpd/libbgp.a $(RFPLDADD) lib/libfrr.la $(LIBCAP) $(LIBM) $(UST_LIBS)
 
 bgpd_bgpd_snmp_la_SOURCES = bgpd/bgp_snmp.c
 bgpd_bgpd_snmp_la_CFLAGS = $(WERROR) $(SNMP_CFLAGS) -std=gnu99