xref: /linux/tools/testing/selftests/drivers/net/hw/xdp_metadata.py (revision 91a4855d6c03e770e42f17c798a36a3c46e63de2)
1#!/usr/bin/env python3
2# SPDX-License-Identifier: GPL-2.0
3
4"""
5Tests for XDP metadata kfuncs (e.g. bpf_xdp_metadata_rx_hash).
6
7These tests load device-bound XDP programs from xdp_metadata.bpf.o
8that call metadata kfuncs, send traffic, and verify the extracted
9metadata via BPF maps.
10"""
11from lib.py import ksft_run, ksft_eq, ksft_exit, ksft_ge, ksft_ne, ksft_pr
12from lib.py import KsftNamedVariant, ksft_variants
13from lib.py import CmdExitFailure, KsftSkipEx, NetDrvEpEnv
14from lib.py import NetdevFamily
15from lib.py import bkg, cmd, rand_port, wait_port_listen
16from lib.py import ip, bpftool, defer
17from lib.py import bpf_map_set, bpf_map_dump, bpf_prog_map_ids
18
19
20def _load_xdp_metadata_prog(cfg, prog_name, bpf_file="xdp_metadata.bpf.o"):
21    """Load a device-bound XDP metadata program and return prog/map info.
22
23    Returns:
24        dict with 'id', 'name', and 'maps' (name -> map_id).
25    """
26    abs_path = cfg.net_lib_dir / bpf_file
27    pin_dir = "/sys/fs/bpf/xdp_metadata_test"
28
29    cmd(f"rm -rf {pin_dir}", shell=True, fail=False)
30    cmd(f"mkdir -p {pin_dir}", shell=True)
31
32    try:
33        bpftool(f"prog loadall {abs_path} {pin_dir} type xdp "
34                f"xdpmeta_dev {cfg.ifname}")
35    except CmdExitFailure as e:
36        cmd(f"rm -rf {pin_dir}", shell=True, fail=False)
37        raise KsftSkipEx(
38            f"Failed to load device-bound XDP program '{prog_name}'"
39        ) from e
40    defer(cmd, f"rm -rf {pin_dir}", shell=True, fail=False)
41
42    pin_path = f"{pin_dir}/{prog_name}"
43    ip(f"link set dev {cfg.ifname} xdpdrv pinned {pin_path}")
44    defer(ip, f"link set dev {cfg.ifname} xdpdrv off")
45
46    xdp_info = ip(f"-d link show dev {cfg.ifname}", json=True)[0]
47    prog_id = xdp_info["xdp"]["prog"]["id"]
48
49    return {"id": prog_id,
50            "name": xdp_info["xdp"]["prog"]["name"],
51            "maps": bpf_prog_map_ids(prog_id)}
52
53
54def _send_probe(cfg, port, proto="tcp"):
55    """Send a single payload from the remote end using socat.
56
57    Args:
58        cfg: Configuration object containing network settings.
59        port: Port number for the exchange.
60        proto: Protocol to use, either "tcp" or "udp".
61    """
62    cfg.require_cmd("socat", remote=True)
63
64    if proto == "tcp":
65        rx_cmd = f"socat -{cfg.addr_ipver} -T 2 TCP-LISTEN:{port},reuseport STDOUT"
66        tx_cmd = f"echo -n rss_hash_test | socat -t 2 -u STDIN TCP:{cfg.baddr}:{port}"
67    else:
68        rx_cmd = f"socat -{cfg.addr_ipver} -T 2 -u UDP-RECV:{port},reuseport STDOUT"
69        tx_cmd = f"echo -n rss_hash_test | socat -t 2 -u STDIN UDP:{cfg.baddr}:{port}"
70
71    with bkg(rx_cmd, exit_wait=True):
72        wait_port_listen(port, proto=proto)
73        cmd(tx_cmd, host=cfg.remote, shell=True)
74
75
76# BPF map keys matching the enums in xdp_metadata.bpf.c
77_SETUP_KEY_PORT = 1
78
79_RSS_KEY_HASH = 0
80_RSS_KEY_TYPE = 1
81_RSS_KEY_PKT_CNT = 2
82_RSS_KEY_ERR_CNT = 3
83
84XDP_RSS_L4 = 0x8  # BIT(3) from enum xdp_rss_hash_type
85
86
87@ksft_variants([
88    KsftNamedVariant("tcp", "tcp"),
89    KsftNamedVariant("udp", "udp"),
90])
91def test_xdp_rss_hash(cfg, proto):
92    """Test RSS hash metadata extraction via bpf_xdp_metadata_rx_hash().
93
94    This test will only run on devices that support xdp-rx-metadata-features.
95
96    Loads the xdp_rss_hash program from xdp_metadata, sends a packet using
97    the specified protocol, and verifies that the program extracted a non-zero
98    hash with an L4 hash type.
99    """
100    dev_info = cfg.netnl.dev_get({"ifindex": cfg.ifindex})
101    rx_meta = dev_info.get("xdp-rx-metadata-features", [])
102    if "hash" not in rx_meta:
103        raise KsftSkipEx("device does not support XDP rx hash metadata")
104
105    prog_info = _load_xdp_metadata_prog(cfg, "xdp_rss_hash")
106
107    port = rand_port()
108    bpf_map_set("map_xdp_setup", _SETUP_KEY_PORT, port)
109
110    rss_map_id = prog_info["maps"]["map_rss"]
111
112    _send_probe(cfg, port, proto=proto)
113
114    rss = bpf_map_dump(rss_map_id)
115
116    pkt_cnt = rss.get(_RSS_KEY_PKT_CNT, 0)
117    err_cnt = rss.get(_RSS_KEY_ERR_CNT, 0)
118    hash_val = rss.get(_RSS_KEY_HASH, 0)
119    hash_type = rss.get(_RSS_KEY_TYPE, 0)
120
121    ksft_ge(pkt_cnt, 1, comment="should have received at least one packet")
122    ksft_eq(err_cnt, 0, comment=f"RSS hash error count: {err_cnt}")
123
124    ksft_ne(hash_val, 0,
125            f"RSS hash should be non-zero for {proto.upper()} traffic")
126    ksft_pr(f"  RSS hash: {hash_val:#010x}")
127
128    ksft_pr(f"  RSS hash type: {hash_type:#06x}")
129    ksft_ne(hash_type & XDP_RSS_L4, 0,
130            f"RSS hash type should include L4 for {proto.upper()} traffic")
131
132
133def main():
134    """Run XDP metadata kfunc tests against a real device."""
135    with NetDrvEpEnv(__file__) as cfg:
136        cfg.netnl = NetdevFamily()
137        ksft_run(
138            [
139                test_xdp_rss_hash,
140            ],
141            args=(cfg,))
142    ksft_exit()
143
144
145if __name__ == "__main__":
146    main()
147