[net-next 1/3] selftests/net: Test PACKET_STATISTICS

[Joe Damato <joe@dama.to>]

Update the existing packet socket test to include a test for the sockopt
PACKET_STATISTICS.

Signed-off-by: Joe Damato <joe@dama.to>
---
 tools/testing/selftests/net/psock_snd.c | 32 ++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/net/psock_snd.c b/tools/testing/selftests/net/psock_snd.c
index edf1e6f80d41..5be481a3d2bd 100644
--- a/tools/testing/selftests/net/psock_snd.c
+++ b/tools/testing/selftests/net/psock_snd.c
@@ -359,6 +359,34 @@ static void parse_opts(int argc, char **argv)
 		error(1, 0, "option gso (-g) requires csum offload (-c)");
 }
 
+static void check_packet_stats(int fd)
+{
+	struct tpacket_stats st = {};
+	socklen_t len = sizeof(st);
+
+	if (getsockopt(fd, SOL_PACKET, PACKET_STATISTICS, &st, &len))
+		error(1, errno, "getsockopt packet statistics");
+
+	if (st.tp_packets != 1)
+		error(1, 0, "stats: tp_packets %u != 1", st.tp_packets);
+
+	if (st.tp_drops != 0)
+		error(1, 0, "stats: tp_drops %u != 0", st.tp_drops);
+
+	/* verify clear on read */
+	memset(&st, 0xff, sizeof(st));
+	len = sizeof(st);
+
+	if (getsockopt(fd, SOL_PACKET, PACKET_STATISTICS, &st, &len))
+		error(1, errno, "getsockopt packet statistics");
+
+	if (st.tp_packets != 0)
+		error(1, 0, "stats: tp_packets %u != 0 after clear", st.tp_packets);
+
+	if (st.tp_drops != 0)
+		error(1, 0, "stats: tp_drops %u != 0 after clear", st.tp_drops);
+}
+
 static void run_test(void)
 {
 	int fdr, fds, total_len;
@@ -369,9 +397,11 @@ static void run_test(void)
 	total_len = do_tx();
 
 	/* BPF filter accepts only this length, vlan changes MAC */
-	if (cfg_payload_len == DATA_LEN && !cfg_use_vlan)
+	if (cfg_payload_len == DATA_LEN && !cfg_use_vlan) {
 		do_rx(fds, total_len - sizeof(struct virtio_net_hdr),
 		      tbuf + sizeof(struct virtio_net_hdr));
+		check_packet_stats(fds);
+	}
 
 	do_rx(fdr, cfg_payload_len, tbuf + total_len - cfg_payload_len);
 
-- 
2.52.0