selftests: xsk: Replace second_step global variable

Replace the second_step global variable with a test specification
variable called total_steps that a test can be set to indicate how
many times the packet stream should be sent without reinitializing any
sockets. This eliminates test specific code in the test runner around
the bidirectional test.

The total_steps variable is 1 by default as most tests only need a
single round of packets.
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/20210907071928.9750-11-magnus.karlsson@gmail.com

tools/testing/selftests/bpf/xdpxceiver.c

@@ -408,6 +408,8 @@ static void __test_spec_init(struct test_spec *test, struct ifobject *ifobj_tx,
 
 	test->ifobj_tx = ifobj_tx;
 	test->ifobj_rx = ifobj_rx;
+	test->current_step = 0;
+	test->total_steps = 1;
 }
 
 static void test_spec_init(struct test_spec *test, struct ifobject *ifobj_tx,
@@ -713,7 +715,7 @@ static bool rx_stats_are_valid(struct ifobject *ifobject)
 	optlen = sizeof(stats);
 	err = getsockopt(fd, SOL_XDP, XDP_STATISTICS, &stats, &optlen);
 	if (err) {
-		ksft_test_result_fail("ERROR: [%s] getsockopt(XDP_STATISTICS) error %u %s\n",
+		ksft_test_result_fail("ERROR Rx: [%s] getsockopt(XDP_STATISTICS) error %u %s\n",
 				      __func__, -err, strerror(-err));
 		return true;
 	}
@@ -754,7 +756,7 @@ static void tx_stats_validate(struct ifobject *ifobject)
 	optlen = sizeof(stats);
 	err = getsockopt(fd, SOL_XDP, XDP_STATISTICS, &stats, &optlen);
 	if (err) {
-		ksft_test_result_fail("ERROR: [%s] getsockopt(XDP_STATISTICS) error %u %s\n",
+		ksft_test_result_fail("ERROR Tx: [%s] getsockopt(XDP_STATISTICS) error %u %s\n",
 				      __func__, -err, strerror(-err));
 		return;
 	}
@@ -766,12 +768,13 @@ static void tx_stats_validate(struct ifobject *ifobject)
 			      __func__, stats.tx_invalid_descs, ifobject->pkt_stream->nb_pkts);
 }
 
-static void thread_common_ops(struct ifobject *ifobject, void *bufs)
+static void thread_common_ops(struct test_spec *test, struct ifobject *ifobject)
 {
 	u64 umem_sz = ifobject->umem->num_frames * ifobject->umem->frame_size;
 	int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
 	size_t mmap_sz = umem_sz;
 	int ctr = 0, ret;
+	void *bufs;
 
 	ifobject->ns_fd = switch_namespace(ifobject->nsname);
 
@@ -813,26 +816,19 @@ static void thread_common_ops(struct ifobject *ifobject, void *bufs)
 	ifobject->xsk = &ifobject->xsk_arr[0];
 }
 
-static bool testapp_is_test_two_stepped(void)
-{
-	return (test_type != TEST_TYPE_BIDI && test_type != TEST_TYPE_BPF_RES) || second_step;
-}
-
 static void testapp_cleanup_xsk_res(struct ifobject *ifobj)
 {
-	if (testapp_is_test_two_stepped()) {
 	xsk_socket__delete(ifobj->xsk->xsk);
-		(void)xsk_umem__delete(ifobj->umem->umem);
-	}
+	xsk_umem__delete(ifobj->umem->umem);
 }
 
 static void *worker_testapp_validate_tx(void *arg)
 {
-	struct ifobject *ifobject = (struct ifobject *)arg;
-	void *bufs = NULL;
+	struct test_spec *test = (struct test_spec *)arg;
+	struct ifobject *ifobject = test->ifobj_tx;
 
-	if (!second_step)
-		thread_common_ops(ifobject, bufs);
+	if (test->current_step == 1)
+		thread_common_ops(test, ifobject);
 
 	print_verbose("Sending %d packets on interface %s\n", ifobject->pkt_stream->nb_pkts,
 		      ifobject->ifname);
@@ -841,18 +837,19 @@ static void *worker_testapp_validate_tx(void *arg)
 	if (stat_test_type == STAT_TEST_TX_INVALID)
 		tx_stats_validate(ifobject);
 
+	if (test->total_steps == test->current_step)
 		testapp_cleanup_xsk_res(ifobject);
 	pthread_exit(NULL);
 }
 
 static void *worker_testapp_validate_rx(void *arg)
 {
-	struct ifobject *ifobject = (struct ifobject *)arg;
+	struct test_spec *test = (struct test_spec *)arg;
+	struct ifobject *ifobject = test->ifobj_rx;
 	struct pollfd fds[MAX_SOCKS] = { };
-	void *bufs = NULL;
 
-	if (!second_step)
-		thread_common_ops(ifobject, bufs);
+	if (test->current_step == 1)
+		thread_common_ops(test, ifobject);
 
 	if (stat_test_type != STAT_TEST_RX_FILL_EMPTY)
 		xsk_populate_fill_ring(ifobject->umem);
@@ -871,6 +868,7 @@ static void *worker_testapp_validate_rx(void *arg)
 	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);
 }
@@ -891,16 +889,17 @@ static void testapp_validate_traffic(struct test_spec *test)
 		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 */
-	pthread_create(&t0, NULL, ifobj_rx->func_ptr, ifobj_rx);
+	pthread_create(&t0, NULL, ifobj_rx->func_ptr, test);
 
 	pthread_barrier_wait(&barr);
 	if (pthread_barrier_destroy(&barr))
 		exit_with_error(errno);
 
 	/*Spawn TX thread */
-	pthread_create(&t1, NULL, ifobj_tx->func_ptr, ifobj_tx);
+	pthread_create(&t1, NULL, ifobj_tx->func_ptr, test);
 
 	pthread_join(t1, NULL);
 	pthread_join(t0, NULL);
@@ -934,15 +933,12 @@ static void testapp_bidi(struct test_spec *test)
 	test_spec_set_name(test, "BIDIRECTIONAL");
 	test->ifobj_tx->rx_on = true;
 	test->ifobj_rx->tx_on = true;
-	for (int i = 0; i < MAX_BIDI_ITER; i++) {
-		print_verbose("Creating socket\n");
+	test->total_steps = 2;
 	testapp_validate_traffic(test);
-		if (!second_step) {
+
 	print_verbose("Switching Tx/Rx vectors\n");
 	swap_directions(&test->ifobj_rx, &test->ifobj_tx);
-		}
-		second_step = true;
-	}
+	testapp_validate_traffic(test);
 
 	swap_directions(&test->ifobj_rx, &test->ifobj_tx);
 }
@@ -961,16 +957,12 @@ static void swap_xsk_resources(struct ifobject *ifobj_tx, struct ifobject *ifobj
 
 static void testapp_bpf_res(struct test_spec *test)
 {
-	int i;
-
 	test_spec_set_name(test, "BPF_RES");
-	for (i = 0; i < MAX_BPF_ITER; i++) {
-		print_verbose("Creating socket\n");
+	test->total_steps = 2;
 	testapp_validate_traffic(test);
-		if (!second_step)
+
 	swap_xsk_resources(test->ifobj_tx, test->ifobj_rx);
-		second_step = true;
-	}
+	testapp_validate_traffic(test);
 }
 
 static void testapp_stats(struct test_spec *test)
@@ -1032,7 +1024,6 @@ static void run_pkt_test(struct test_spec *test, int mode, int type)
 
 	/* reset defaults after potential previous test */
 	xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
-	second_step = 0;
 	stat_test_type = -1;
 
 	configured_mode = mode;

tools/testing/selftests/bpf/xdpxceiver.h

@@ -24,7 +24,6 @@
 #define MAX_SOCKETS 2
 #define MAX_TEST_NAME_SIZE 32
 #define MAX_TEARDOWN_ITER 10
-#define MAX_BIDI_ITER 2
 #define MAX_BPF_ITER 2
 #define PKT_HDR_SIZE (sizeof(struct ethhdr) + sizeof(struct iphdr) + \
 			sizeof(struct udphdr))
@@ -72,7 +71,6 @@ enum stat_test_type {
 
 static int configured_mode;
 static bool opt_pkt_dump;
-static bool second_step;
 static int test_type;
 
 static bool opt_verbose;
@@ -137,6 +135,8 @@ struct ifobject {
 struct test_spec {
 	struct ifobject *ifobj_tx;
 	struct ifobject *ifobj_rx;
+	u16 total_steps;
+	u16 current_step;
 	char name[MAX_TEST_NAME_SIZE];
 };