Commit bb6a8888 authored by Larysa Zaremba's avatar Larysa Zaremba Committed by Daniel Borkmann
Browse files

selftests/bpf: Add options and frags to xdp_hw_metadata 

This is a follow-up to the commit 9b2b8633 ("bpf: Allow to use kfunc
XDP hints and frags together").

The are some possible implementations problems that may arise when providing
metadata specifically for multi-buffer packets, therefore there must be a
possibility to test such option separately.

Add an option to use multi-buffer AF_XDP xdp_hw_metadata and mark used XDP
program as capable to use frags.

As for now, xdp_hw_metadata accepts no options, so add simple option
parsing logic and a help message.

For quick reference, also add an ingress packet generation command to the
help message. The command comes from [0].

Example of output for multi-buffer packet:

  xsk_ring_cons__peek: 1
  0xead018: rx_desc[15]->addr=10000000000f000 addr=f100 comp_addr=f000
  rx_hash: 0x5789FCBB with RSS type:0x29
  rx_timestamp:  1696856851535324697 (sec:1696856851.5353)
  XDP RX-time:   1696856843158256391 (sec:1696856843.1583)
  	delta sec:-8.3771 (-8377068.306 usec)
  AF_XDP time:   1696856843158413078 (sec:1696856843.1584)
  	delta sec:0.0002 (156.687 usec)
  0xead018: complete idx=23 addr=f000
  xsk_ring_cons__peek: 1
  0xead018: rx_desc[16]->addr=100000000008000 addr=8100 comp_addr=8000
  0xead018: complete idx=24 addr=8000
  xsk_ring_cons__peek: 1
  0xead018: rx_desc[17]->addr=100000000009000 addr=9100 comp_addr=9000 EoP
  0xead018: complete idx=25 addr=9000

Metadata is printed for the first packet only.

  [0] https://lore.kernel.org/all/20230119221536.3349901-18-sdf@google.com/



Signed-off-by: default avatarLarysa Zaremba <larysa.zaremba@intel.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarStanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20231017162800.24080-1-larysa.zaremba@intel.com
parent 24516309

tools/testing/selftests/bpf/progs/xdp_hw_metadata.c

+1 −1
Original line number Diff line number Diff line
@@ -21,7 +21,7 @@ extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx, 
extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, __u32 *hash,

				    enum xdp_rss_hash_type *rss_type) __ksym;



SEC("xdp")

SEC("xdp.frags")

int rx(struct xdp_md *ctx)

{

	void *data, *data_meta, *data_end;

tools/testing/selftests/bpf/xdp_hw_metadata.c

+66 −12
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ 
#include <linux/sockios.h>

#include <sys/mman.h>

#include <net/if.h>

#include <ctype.h>

#include <poll.h>

#include <time.h>
@@ -47,6 +48,7 @@ struct xsk { 
};



struct xdp_hw_metadata *bpf_obj;

__u16 bind_flags = XDP_COPY;

struct xsk *rx_xsk;

const char *ifname;

int ifindex;
@@ -60,7 +62,7 @@ static int open_xsk(int ifindex, struct xsk *xsk, __u32 queue_id) 
	const struct xsk_socket_config socket_config = {

		.rx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,

		.tx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,

		.bind_flags = XDP_COPY,

		.bind_flags = bind_flags,

	};

	const struct xsk_umem_config umem_config = {

		.fill_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
@@ -263,11 +265,14 @@ static int verify_metadata(struct xsk *rx_xsk, int rxq, int server_fd, clockid_t 
			verify_skb_metadata(server_fd);



		for (i = 0; i < rxq; i++) {

			bool first_seg = true;

			bool is_eop = true;



			if (fds[i].revents == 0)

				continue;



			struct xsk *xsk = &rx_xsk[i];



peek:

			ret = xsk_ring_cons__peek(&xsk->rx, 1, &idx);

			printf("xsk_ring_cons__peek: %d\n", ret);

			if (ret != 1)
@@ -276,12 +281,19 @@ static int verify_metadata(struct xsk *rx_xsk, int rxq, int server_fd, clockid_t 
			rx_desc = xsk_ring_cons__rx_desc(&xsk->rx, idx);

			comp_addr = xsk_umem__extract_addr(rx_desc->addr);

			addr = xsk_umem__add_offset_to_addr(rx_desc->addr);

			printf("%p: rx_desc[%u]->addr=%llx addr=%llx comp_addr=%llx\n",

			       xsk, idx, rx_desc->addr, addr, comp_addr);

			is_eop = !(rx_desc->options & XDP_PKT_CONTD);

			printf("%p: rx_desc[%u]->addr=%llx addr=%llx comp_addr=%llx%s\n",

			       xsk, idx, rx_desc->addr, addr, comp_addr, is_eop ? " EoP" : "");

			if (first_seg) {

				verify_xdp_metadata(xsk_umem__get_data(xsk->umem_area, addr),

						    clock_id);

				first_seg = false;

			}



			xsk_ring_cons__release(&xsk->rx, 1);

			refill_rx(xsk, comp_addr);

			if (!is_eop)

				goto peek;

		}

	}
@@ -404,6 +416,53 @@ static void timestamping_enable(int fd, int val) 
		error(1, errno, "setsockopt(SO_TIMESTAMPING)");

}



static void print_usage(void)

{

	const char *usage =

		"Usage: xdp_hw_metadata [OPTIONS] [IFNAME]\n"

		"  -m    Enable multi-buffer XDP for larger MTU\n"

		"  -h    Display this help and exit\n\n"

		"Generate test packets on the other machine with:\n"

		"  echo -n xdp | nc -u -q1 <dst_ip> 9091\n";



	printf("%s", usage);

}



static void read_args(int argc, char *argv[])

{

	char opt;



	while ((opt = getopt(argc, argv, "mh")) != -1) {

		switch (opt) {

		case 'm':

			bind_flags |= XDP_USE_SG;

			break;

		case 'h':

			print_usage();

			exit(0);

		case '?':

			if (isprint(optopt))

				fprintf(stderr, "Unknown option: -%c\n", optopt);

			fallthrough;

		default:

			print_usage();

			error(-1, opterr, "Command line options error");

		}

	}



	if (optind >= argc) {

		fprintf(stderr, "No device name provided\n");

		print_usage();

		exit(-1);

	}



	ifname = argv[optind];

	ifindex = if_nametoindex(ifname);



	if (!ifname)

		error(-1, errno, "Invalid interface name");

}



int main(int argc, char *argv[])

{

	clockid_t clock_id = CLOCK_TAI;
@@ -413,13 +472,8 @@ int main(int argc, char *argv[]) 


	struct bpf_program *prog;



	if (argc != 2) {

		fprintf(stderr, "pass device name\n");

		return -1;

	}

	read_args(argc, argv);



	ifname = argv[1];

	ifindex = if_nametoindex(ifname);

	rxq = rxq_num(ifname);



	printf("rxq: %d\n", rxq);