selftests: xsk: Introduce replacing the default packet stream

Introduce the concept of a default packet stream that is the set of
packets sent by most tests. Then add the ability to replace it for a
test that would like to send or receive something else through the use
of the function pkt_stream_replace() and then restored with
pkt_stream_restore_default(). These are then used to convert the
STAT_TEST_TX_INVALID to use these new APIs.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-17-magnus.karlsson@gmail.com

Author: magnus-karlsson

tools/testing/selftests/bpf/xdpxceiver.c

@@ -390,6 +390,7 @@ static void __test_spec_init(struct test_spec *test, struct ifobject *ifobj_tx,
 		ifobj->umem = &ifobj->umem_arr[0];
 		ifobj->xsk = &ifobj->xsk_arr[0];
 		ifobj->use_poll = false;
+		ifobj->pkt_stream = test->pkt_stream_default;
 
 		if (i == 0) {
 			ifobj->rx_on = false;
@@ -418,9 +419,12 @@ static void __test_spec_init(struct test_spec *test, struct ifobject *ifobj_tx,
 static void test_spec_init(struct test_spec *test, struct ifobject *ifobj_tx,
 			   struct ifobject *ifobj_rx, enum test_mode mode)
 {
+	struct pkt_stream *pkt_stream;
 	u32 i;
 
+	pkt_stream = test->pkt_stream_default;
 	memset(test, 0, sizeof(*test));
+	test->pkt_stream_default = pkt_stream;
 
 	for (i = 0; i < MAX_INTERFACES; i++) {
 		struct ifobject *ifobj = i ? ifobj_rx : ifobj_tx;
@@ -455,6 +459,19 @@ static struct pkt *pkt_stream_get_pkt(struct pkt_stream *pkt_stream, u32 pkt_nb)
 	return &pkt_stream->pkts[pkt_nb];
 }
 
+static void pkt_stream_delete(struct pkt_stream *pkt_stream)
+{
+	free(pkt_stream->pkts);
+	free(pkt_stream);
+}
+
+static void pkt_stream_restore_default(struct test_spec *test)
+{
+	pkt_stream_delete(test->ifobj_tx->pkt_stream);
+	test->ifobj_tx->pkt_stream = test->pkt_stream_default;
+	test->ifobj_rx->pkt_stream = test->pkt_stream_default;
+}
+
 static struct pkt_stream *pkt_stream_generate(struct xsk_umem_info *umem, u32 nb_pkts, u32 pkt_len)
 {
 	struct pkt_stream *pkt_stream;
@@ -483,6 +500,15 @@ static struct pkt_stream *pkt_stream_generate(struct xsk_umem_info *umem, u32 nb
 	return pkt_stream;
 }
 
+static void pkt_stream_replace(struct test_spec *test, u32 nb_pkts, u32 pkt_len)
+{
+	struct pkt_stream *pkt_stream;
+
+	pkt_stream = pkt_stream_generate(test->ifobj_tx->umem, nb_pkts, pkt_len);
+	test->ifobj_tx->pkt_stream = pkt_stream;
+	test->ifobj_rx->pkt_stream = pkt_stream;
+}
+
 static struct pkt *pkt_generate(struct ifobject *ifobject, u32 pkt_nb)
 {
 	struct pkt *pkt = pkt_stream_get_pkt(ifobject->pkt_stream, pkt_nb);
@@ -557,7 +583,7 @@ static bool is_pkt_valid(struct pkt *pkt, void *buffer, const struct xdp_desc *d
 	if (iphdr->version == IP_PKT_VER && iphdr->tos == IP_PKT_TOS) {
 		u32 seqnum = ntohl(*((u32 *)(data + PKT_HDR_SIZE)));
 
-		if (opt_pkt_dump && test_type != TEST_TYPE_STATS)
+		if (opt_pkt_dump)
 			pkt_dump(data, PKT_SIZE);
 
 		if (pkt->len != desc->len) {
@@ -598,9 +624,6 @@ static void complete_pkts(struct xsk_socket_info *xsk, int batch_size)
 	unsigned int rcvd;
 	u32 idx;
 
-	if (!xsk->outstanding_tx)
-		return;
-
 	if (xsk_ring_prod__needs_wakeup(&xsk->tx))
 		kick_tx(xsk);
 
@@ -831,6 +854,7 @@ static void thread_common_ops(struct test_spec *test, struct ifobject *ifobject)
 
 static void testapp_cleanup_xsk_res(struct ifobject *ifobj)
 {
+	print_verbose("Destroying socket\n");
 	xsk_socket__delete(ifobj->xsk->xsk);
 	xsk_umem__delete(ifobj->umem->umem);
 }
@@ -878,9 +902,6 @@ static void *worker_testapp_validate_rx(void *arg)
 	else
 		receive_pkts(ifobject->pkt_stream, ifobject->xsk, &fds);
 
-	if (test_type == TEST_TYPE_TEARDOWN)
-		print_verbose("Destroying socket\n");
-
 	if (test->total_steps == test->current_step)
 		testapp_cleanup_xsk_res(ifobject);
 	pthread_exit(NULL);
@@ -890,19 +911,11 @@ static void testapp_validate_traffic(struct test_spec *test)
 {
 	struct ifobject *ifobj_tx = test->ifobj_tx;
 	struct ifobject *ifobj_rx = test->ifobj_rx;
-	struct pkt_stream *pkt_stream;
 	pthread_t t0, t1;
 
 	if (pthread_barrier_init(&barr, NULL, 2))
 		exit_with_error(errno);
 
-	if (stat_test_type == STAT_TEST_TX_INVALID)
-		pkt_stream = pkt_stream_generate(test->ifobj_tx->umem, DEFAULT_PKT_CNT,
-						 XSK_UMEM__INVALID_FRAME_SIZE);
-	else
-		pkt_stream = pkt_stream_generate(test->ifobj_tx->umem, DEFAULT_PKT_CNT, PKT_SIZE);
-	ifobj_tx->pkt_stream = pkt_stream;
-	ifobj_rx->pkt_stream = pkt_stream;
 	test->current_step++;
 
 	/*Spawn RX thread */
@@ -982,7 +995,9 @@ static void testapp_bpf_res(struct test_spec *test)
 
 static void testapp_stats(struct test_spec *test)
 {
-	for (int i = 0; i < STAT_TEST_TYPE_MAX; i++) {
+	int i;
+
+	for (i = 0; i < STAT_TEST_TYPE_MAX; i++) {
 		test_spec_reset(test);
 		stat_test_type = i;
 
@@ -991,21 +1006,27 @@ static void testapp_stats(struct test_spec *test)
 			test_spec_set_name(test, "STAT_RX_DROPPED");
 			test->ifobj_rx->umem->frame_headroom = test->ifobj_rx->umem->frame_size -
 				XDP_PACKET_HEADROOM - 1;
+			testapp_validate_traffic(test);
 			break;
 		case STAT_TEST_RX_FULL:
 			test_spec_set_name(test, "STAT_RX_FULL");
 			test->ifobj_rx->xsk->rxqsize = RX_FULL_RXQSIZE;
+			testapp_validate_traffic(test);
 			break;
 		case STAT_TEST_TX_INVALID:
 			test_spec_set_name(test, "STAT_TX_INVALID");
-			continue;
+			pkt_stream_replace(test, DEFAULT_PKT_CNT, XSK_UMEM__INVALID_FRAME_SIZE);
+			testapp_validate_traffic(test);
+
+			pkt_stream_restore_default(test);
+			break;
 		case STAT_TEST_RX_FILL_EMPTY:
 			test_spec_set_name(test, "STAT_RX_FILL_EMPTY");
+			testapp_validate_traffic(test);
 			break;
 		default:
 			break;
 		}
-		testapp_validate_traffic(test);
 	}
 
 	/* To only see the whole stat set being completed unless an individual test fails. */
@@ -1105,6 +1126,7 @@ static void ifobject_delete(struct ifobject *ifobj)
 int main(int argc, char **argv)
 {
 	struct rlimit _rlim = { RLIM_INFINITY, RLIM_INFINITY };
+	struct pkt_stream *pkt_stream_default;
 	struct ifobject *ifobj_tx, *ifobj_rx;
 	struct test_spec test;
 	u32 i, j;
@@ -1133,6 +1155,12 @@ int main(int argc, char **argv)
 	init_iface(ifobj_rx, MAC2, MAC1, IP2, IP1, UDP_PORT2, UDP_PORT1,
 		   worker_testapp_validate_rx);
 
+	test_spec_init(&test, ifobj_tx, ifobj_rx, 0);
+	pkt_stream_default = pkt_stream_generate(ifobj_tx->umem, DEFAULT_PKT_CNT, PKT_SIZE);
+	if (!pkt_stream_default)
+		exit_with_error(ENOMEM);
+	test.pkt_stream_default = pkt_stream_default;
+
 	ksft_set_plan(TEST_MODE_MAX * TEST_TYPE_MAX);
 
 	for (i = 0; i < TEST_MODE_MAX; i++)
@@ -1142,6 +1170,7 @@ int main(int argc, char **argv)
 			usleep(USLEEP_MAX);
 		}
 
+	pkt_stream_delete(pkt_stream_default);
 	ifobject_delete(ifobj_tx);
 	ifobject_delete(ifobj_rx);
 

tools/testing/selftests/bpf/xdpxceiver.h

@@ -132,6 +132,7 @@ struct ifobject {
 struct test_spec {
 	struct ifobject *ifobj_tx;
 	struct ifobject *ifobj_rx;
+	struct pkt_stream *pkt_stream_default;
 	u16 total_steps;
 	u16 current_step;
 	u16 nb_sockets;