[PATCH v2] udp6: add a missing call into udp_fail_queue_rcv_skb tracepoint

[Ivan Babrou <ivan@cloudflare.com>]

The tracepoint has existed for 12 years, but it only covered udp
over the legacy IPv4 protocol. Having it enabled for udp6 removes
the unnecessary difference in error visibility.

Signed-off-by: Ivan Babrou <ivan@cloudflare.com>
Fixes: 296f7ea75b45 ("udp: add tracepoints for queueing skb to rcvbuf")

---
v2: added tracepoint export to make it build with IPV6=m (thanks Jakub!)
---
 net/core/net-traces.c | 2 ++
 net/ipv6/udp.c        | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/net/core/net-traces.c b/net/core/net-traces.c
index 805b7385dd8d..6aef976bc1da 100644
--- a/net/core/net-traces.c
+++ b/net/core/net-traces.c
@@ -63,4 +63,6 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(napi_poll);
 EXPORT_TRACEPOINT_SYMBOL_GPL(tcp_send_reset);
 EXPORT_TRACEPOINT_SYMBOL_GPL(tcp_bad_csum);
 
+EXPORT_TRACEPOINT_SYMBOL_GPL(udp_fail_queue_rcv_skb);
+
 EXPORT_TRACEPOINT_SYMBOL_GPL(sk_data_ready);
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index e5a337e6b970..debb98fb23c0 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -45,6 +45,7 @@
 #include <net/tcp_states.h>
 #include <net/ip6_checksum.h>
 #include <net/ip6_tunnel.h>
+#include <trace/events/udp.h>
 #include <net/xfrm.h>
 #include <net/inet_hashtables.h>
 #include <net/inet6_hashtables.h>
@@ -680,6 +681,7 @@ static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 		}
 		UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 		kfree_skb_reason(skb, drop_reason);
+		trace_udp_fail_queue_rcv_skb(rc, sk);
 		return -1;
 	}
 
-- 
2.41.0