selftests: xsk: Simplify packet validation in xsk tests

Simplify packet validation in the xsk selftests by performing it at
once for every packet. The current code performed this per batch and
did this on copied packet data. Make it simpler and faster by
validating it at once and on the umem packet data thus skipping the
copy and the memory allocation for the temprary buffer.

The optional packet dump feature is also simplified in the same
manner. Memory allocation and copying is removed and the dump is
performed directly on the umem data.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210825093722.10219-10-magnus.karlsson@gmail.com

tools/testing/selftests/bpf/xdpxceiver.c

@@ -427,6 +427,70 @@ static void parse_command_line(int argc, char **argv)
 	}
 }
 
+static void pkt_dump(void *pkt, u32 len)
+{
+	char s[INET_ADDRSTRLEN];
+	struct ethhdr *ethhdr;
+	struct udphdr *udphdr;
+	struct iphdr *iphdr;
+	int payload, i;
+
+	ethhdr = pkt;
+	iphdr = pkt + sizeof(*ethhdr);
+	udphdr = pkt + sizeof(*ethhdr) + sizeof(*iphdr);
+
+	/*extract L2 frame */
+	fprintf(stdout, "DEBUG>> L2: dst mac: ");
+	for (i = 0; i < ETH_ALEN; i++)
+		fprintf(stdout, "%02X", ethhdr->h_dest[i]);
+
+	fprintf(stdout, "\nDEBUG>> L2: src mac: ");
+	for (i = 0; i < ETH_ALEN; i++)
+		fprintf(stdout, "%02X", ethhdr->h_source[i]);
+
+	/*extract L3 frame */
+	fprintf(stdout, "\nDEBUG>> L3: ip_hdr->ihl: %02X\n", iphdr->ihl);
+	fprintf(stdout, "DEBUG>> L3: ip_hdr->saddr: %s\n",
+		inet_ntop(AF_INET, &iphdr->saddr, s, sizeof(s)));
+	fprintf(stdout, "DEBUG>> L3: ip_hdr->daddr: %s\n",
+		inet_ntop(AF_INET, &iphdr->daddr, s, sizeof(s)));
+	/*extract L4 frame */
+	fprintf(stdout, "DEBUG>> L4: udp_hdr->src: %d\n", ntohs(udphdr->source));
+	fprintf(stdout, "DEBUG>> L4: udp_hdr->dst: %d\n", ntohs(udphdr->dest));
+	/*extract L5 frame */
+	payload = *((uint32_t *)(pkt + PKT_HDR_SIZE));
+
+	fprintf(stdout, "DEBUG>> L5: payload: %d\n", payload);
+	fprintf(stdout, "---------------------------------------\n");
+}
+
+static void pkt_validate(void *pkt)
+{
+	struct iphdr *iphdr = (struct iphdr *)(pkt + sizeof(struct ethhdr));
+
+	/*do not increment pktcounter if !(tos=0x9 and ipv4) */
+	if (iphdr->version == IP_PKT_VER && iphdr->tos == IP_PKT_TOS) {
+		u32 payloadseqnum = *((uint32_t *)(pkt + PKT_HDR_SIZE));
+
+		if (debug_pkt_dump && test_type != TEST_TYPE_STATS)
+			pkt_dump(pkt, PKT_SIZE);
+
+		if (pkt_counter % num_frames != payloadseqnum) {
+			ksft_test_result_fail
+				("ERROR: [%s] expected seqnum [%d], got seqnum [%d]\n",
+					__func__, pkt_counter, payloadseqnum);
+			ksft_exit_xfail();
+		}
+
+		if (++pkt_counter == opt_pkt_count)
+			sigvar = 1;
+	} else {
+		ksft_print_msg("Invalid frame received: ");
+		ksft_print_msg("[IP_PKT_VER: %02X], [IP_PKT_TOS: %02X]\n", iphdr->version,
+			       iphdr->tos);
+	}
+}
+
 static void kick_tx(struct xsk_socket_info *xsk)
 {
 	int ret;
@@ -491,18 +555,7 @@ static void rx_pkt(struct xsk_socket_info *xsk, struct pollfd *fds)
 		orig = xsk_umem__extract_addr(addr);
 
 		addr = xsk_umem__add_offset_to_addr(addr);
-		pkt_node_rx = malloc(sizeof(struct pkt) + PKT_SIZE);
-		if (!pkt_node_rx)
-			exit_with_error(errno);
-
-		pkt_node_rx->pkt_frame = malloc(PKT_SIZE);
-		if (!pkt_node_rx->pkt_frame)
-			exit_with_error(errno);
-
-		memcpy(pkt_node_rx->pkt_frame, xsk_umem__get_data(xsk->umem->buffer, addr),
-		       PKT_SIZE);
-
-		TAILQ_INSERT_HEAD(&head, pkt_node_rx, pkt_nodes);
+		pkt_validate(xsk_umem__get_data(xsk->umem->buffer, addr));
 
 		*xsk_ring_prod__fill_addr(&xsk->umem->fq, idx_fq++) = orig;
 	}
@@ -589,48 +642,6 @@ static void tx_only_all(struct ifobject *ifobject)
 	complete_tx_only_all(ifobject);
 }
 
-static void pkt_dump(void)
-{
-	struct ethhdr *ethhdr;
-	struct iphdr *iphdr;
-	struct udphdr *udphdr;
-	char s[128];
-	int payload;
-	void *ptr;
-
-	fprintf(stdout, "---------------------------------------\n");
-	for (int iter = 0; iter < num_frames; iter++) {
-		ptr = pkt_buf[iter]->payload;
-		ethhdr = ptr;
-		iphdr = ptr + sizeof(*ethhdr);
-		udphdr = ptr + sizeof(*ethhdr) + sizeof(*iphdr);
-
-		/*extract L2 frame */
-		fprintf(stdout, "DEBUG>> L2: dst mac: ");
-		for (int i = 0; i < ETH_ALEN; i++)
-			fprintf(stdout, "%02X", ethhdr->h_dest[i]);
-
-		fprintf(stdout, "\nDEBUG>> L2: src mac: ");
-		for (int i = 0; i < ETH_ALEN; i++)
-			fprintf(stdout, "%02X", ethhdr->h_source[i]);
-
-		/*extract L3 frame */
-		fprintf(stdout, "\nDEBUG>> L3: ip_hdr->ihl: %02X\n", iphdr->ihl);
-		fprintf(stdout, "DEBUG>> L3: ip_hdr->saddr: %s\n",
-			inet_ntop(AF_INET, &iphdr->saddr, s, sizeof(s)));
-		fprintf(stdout, "DEBUG>> L3: ip_hdr->daddr: %s\n",
-			inet_ntop(AF_INET, &iphdr->daddr, s, sizeof(s)));
-		/*extract L4 frame */
-		fprintf(stdout, "DEBUG>> L4: udp_hdr->src: %d\n", ntohs(udphdr->source));
-		fprintf(stdout, "DEBUG>> L4: udp_hdr->dst: %d\n", ntohs(udphdr->dest));
-		/*extract L5 frame */
-		payload = *((uint32_t *)(ptr + PKT_HDR_SIZE));
-
-		fprintf(stdout, "DEBUG>> L5: payload: %d\n", payload);
-		fprintf(stdout, "---------------------------------------\n");
-	}
-}
-
 static void stats_validate(struct ifobject *ifobject)
 {
 	struct xdp_statistics stats;
@@ -673,52 +684,6 @@ static void stats_validate(struct ifobject *ifobject)
 	}
 }
 
-static void pkt_validate(void)
-{
-	u32 payloadseqnum = -2;
-	struct iphdr *iphdr;
-
-	while (1) {
-		pkt_node_rx_q = TAILQ_LAST(&head, head_s);
-		if (!pkt_node_rx_q)
-			break;
-
-		iphdr = (struct iphdr *)(pkt_node_rx_q->pkt_frame + sizeof(struct ethhdr));
-
-		/*do not increment pktcounter if !(tos=0x9 and ipv4) */
-		if (iphdr->version == IP_PKT_VER && iphdr->tos == IP_PKT_TOS) {
-			payloadseqnum = *((uint32_t *)(pkt_node_rx_q->pkt_frame + PKT_HDR_SIZE));
-			if (debug_pkt_dump) {
-				pkt_obj = malloc(sizeof(*pkt_obj));
-				pkt_obj->payload = malloc(PKT_SIZE);
-				memcpy(pkt_obj->payload, pkt_node_rx_q->pkt_frame, PKT_SIZE);
-				pkt_buf[payloadseqnum] = pkt_obj;
-			}
-
-			if (pkt_counter % num_frames != payloadseqnum) {
-				ksft_test_result_fail
-				    ("ERROR: [%s] expected counter [%d], payloadseqnum [%d]\n",
-				     __func__, pkt_counter, payloadseqnum);
-				ksft_exit_xfail();
-			}
-
-			if (++pkt_counter == opt_pkt_count) {
-				sigvar = 1;
-				break;
-			}
-		} else {
-			ksft_print_msg("Invalid frame received: ");
-			ksft_print_msg("[IP_PKT_VER: %02X], [IP_PKT_TOS: %02X]\n", iphdr->version,
-				       iphdr->tos);
-		}
-
-		TAILQ_REMOVE(&head, pkt_node_rx_q, pkt_nodes);
-		free(pkt_node_rx_q->pkt_frame);
-		free(pkt_node_rx_q);
-		pkt_node_rx_q = NULL;
-	}
-}
-
 static void thread_common_ops(struct ifobject *ifobject, void *bufs)
 {
 	u64 umem_sz = num_frames * XSK_UMEM__DEFAULT_FRAME_SIZE;
@@ -818,13 +783,6 @@ static void *worker_testapp_validate_rx(void *arg)
 	if (stat_test_type != STAT_TEST_RX_FILL_EMPTY)
 		xsk_populate_fill_ring(ifobject->umem);
 
-	TAILQ_INIT(&head);
-	if (debug_pkt_dump) {
-		pkt_buf = calloc(num_frames, sizeof(*pkt_buf));
-		if (!pkt_buf)
-			exit_with_error(errno);
-	}
-
 	fds[0].fd = xsk_socket__fd(ifobject->xsk->xsk);
 	fds[0].events = POLLIN;
 
@@ -833,7 +791,6 @@ static void *worker_testapp_validate_rx(void *arg)
 	while (1) {
 		if (test_type != TEST_TYPE_STATS) {
 			rx_pkt(ifobject->xsk, fds);
-			pkt_validate();
 		} else {
 			stats_validate(ifobject);
 		}
@@ -872,15 +829,6 @@ static void testapp_validate(void)
 	pthread_join(t1, NULL);
 	pthread_join(t0, NULL);
 
-	if (debug_pkt_dump && test_type != TEST_TYPE_STATS) {
-		pkt_dump();
-		for (int iter = 0; iter < num_frames; iter++) {
-			free(pkt_buf[iter]->payload);
-			free(pkt_buf[iter]);
-		}
-		free(pkt_buf);
-	}
-
 	if (!(test_type == TEST_TYPE_TEARDOWN) && !bidi && !bpf && !(test_type == TEST_TYPE_STATS))
 		print_ksft_result();
 }

tools/testing/selftests/bpf/xdpxceiver.h

@@ -139,18 +139,4 @@ static struct ifobject *ifdict_tx;
 pthread_barrier_t barr;
 pthread_t t0, t1;
 
-TAILQ_HEAD(head_s, pkt) head = TAILQ_HEAD_INITIALIZER(head);
-struct head_s *head_p;
-struct pkt {
-	char *pkt_frame;
-
-	TAILQ_ENTRY(pkt) pkt_nodes;
-} *pkt_node_rx, *pkt_node_rx_q;
-
-struct pkt_frame {
-	char *payload;
-} *pkt_obj;
-
-struct pkt_frame **pkt_buf;
-
 #endif				/* XDPXCEIVER_H */