From 91aacd8ceffe6f07b324c5548c6efd763ae0e278 Mon Sep 17 00:00:00 2001 From: Dimitri Daskalakis Date: Wed, 20 Aug 2025 18:40:21 -0700 Subject: [PATCH 1/3] selftests: drv-net: xdp: Extract common XDP_TX setup/validation. In preparation of single-buffer XDP_TX tests, refactor common test code into the _test_xdp_native_tx method. Add support for multiple payload sizes, and additional validation for RX packet count. Pass the -n flag to echo to avoid adding an extra byte into the TX packet. Signed-off-by: Dimitri Daskalakis Link: https://patch.msgid.link/20250821014023.1481662-2-dimitri.daskalakis1@gmail.com Signed-off-by: Jakub Kicinski --- tools/testing/selftests/drivers/net/xdp.py | 63 ++++++++++++++-------- 1 file changed, 42 insertions(+), 21 deletions(-) diff --git a/tools/testing/selftests/drivers/net/xdp.py b/tools/testing/selftests/drivers/net/xdp.py index 1dd8bf3bf6c9..ea4da9024f9f 100755 --- a/tools/testing/selftests/drivers/net/xdp.py +++ b/tools/testing/selftests/drivers/net/xdp.py @@ -290,6 +290,45 @@ def test_xdp_native_drop_mb(cfg): _test_drop(cfg, bpf_info, 8000) +def _test_xdp_native_tx(cfg, bpf_info, payload_lens): + """ + Tests the XDP_TX action. + + Args: + cfg: Configuration object containing network settings. + bpf_info: BPFProgInfo object containing the BPF program metadata. + payload_lens: Array of packet lengths to send. + """ + cfg.require_cmd("socat", remote=True) + prog_info = _load_xdp_prog(cfg, bpf_info) + port = rand_port() + + _set_xdp_map("map_xdp_setup", TestConfig.MODE.value, XDPAction.TX.value) + _set_xdp_map("map_xdp_setup", TestConfig.PORT.value, port) + + expected_pkts = 0 + for payload_len in payload_lens: + test_string = "".join( + random.choice(string.ascii_lowercase) for _ in range(payload_len) + ) + + rx_udp = f"socat -{cfg.addr_ipver} -T 2 " + \ + f"-u UDP-RECV:{port},reuseport STDOUT" + tx_udp = f"echo -n {test_string} | socat -t 2 " + \ + f"-u STDIN UDP:{cfg.baddr}:{port}" + + with bkg(rx_udp, host=cfg.remote, exit_wait=True) as rnc: + wait_port_listen(port, proto="udp", host=cfg.remote) + cmd(tx_udp, host=cfg.remote, shell=True) + + ksft_eq(rnc.stdout.strip(), test_string, "UDP packet exchange failed") + + expected_pkts += 1 + stats = _get_stats(prog_info["maps"]["map_xdp_stats"]) + ksft_eq(stats[XDPStats.RX.value], expected_pkts, "RX stats mismatch") + ksft_eq(stats[XDPStats.TX.value], expected_pkts, "TX stats mismatch") + + def test_xdp_native_tx_mb(cfg): """ Tests the XDP_TX action for a multi-buff case. @@ -297,27 +336,9 @@ def test_xdp_native_tx_mb(cfg): Args: cfg: Configuration object containing network settings. """ - cfg.require_cmd("socat", remote=True) - - bpf_info = BPFProgInfo("xdp_prog_frags", "xdp_native.bpf.o", "xdp.frags", 9000) - prog_info = _load_xdp_prog(cfg, bpf_info) - port = rand_port() - - _set_xdp_map("map_xdp_setup", TestConfig.MODE.value, XDPAction.TX.value) - _set_xdp_map("map_xdp_setup", TestConfig.PORT.value, port) - - test_string = ''.join(random.choice(string.ascii_lowercase) for _ in range(8000)) - rx_udp = f"socat -{cfg.addr_ipver} -T 2 -u UDP-RECV:{port},reuseport STDOUT" - tx_udp = f"echo {test_string} | socat -t 2 -u STDIN UDP:{cfg.baddr}:{port}" - - with bkg(rx_udp, host=cfg.remote, exit_wait=True) as rnc: - wait_port_listen(port, proto="udp", host=cfg.remote) - cmd(tx_udp, host=cfg.remote, shell=True) - - stats = _get_stats(prog_info['maps']['map_xdp_stats']) - - ksft_eq(rnc.stdout.strip(), test_string, "UDP packet exchange failed") - ksft_eq(stats[XDPStats.TX.value], 1, "TX stats mismatch") + bpf_info = BPFProgInfo("xdp_prog_frags", "xdp_native.bpf.o", + "xdp.frags", 9000) + _test_xdp_native_tx(cfg, bpf_info, [8000]) def _validate_res(res, offset_lst, pkt_sz_lst): From d06d70eb6af441c59ec8fc71df0c47427321318b Mon Sep 17 00:00:00 2001 From: Dimitri Daskalakis Date: Wed, 20 Aug 2025 18:40:22 -0700 Subject: [PATCH 2/3] selftests: drv-net: xdp: Add a single-buffer XDP_TX test. Test single-buffer XDP_TX for packets with various payload sizes. Update the socat TX command to generate packets with 0 length payloads. Signed-off-by: Dimitri Daskalakis Link: https://patch.msgid.link/20250821014023.1481662-3-dimitri.daskalakis1@gmail.com Signed-off-by: Jakub Kicinski --- tools/testing/selftests/drivers/net/xdp.py | 23 +++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/drivers/net/xdp.py b/tools/testing/selftests/drivers/net/xdp.py index ea4da9024f9f..cea24c9b573e 100755 --- a/tools/testing/selftests/drivers/net/xdp.py +++ b/tools/testing/selftests/drivers/net/xdp.py @@ -314,8 +314,13 @@ def _test_xdp_native_tx(cfg, bpf_info, payload_lens): rx_udp = f"socat -{cfg.addr_ipver} -T 2 " + \ f"-u UDP-RECV:{port},reuseport STDOUT" + + # Writing zero bytes to stdin gets ignored by socat, + # but with the shut-null flag socat generates a zero sized packet + # when the socket is closed. + tx_cmd_suffix = ",shut-null" if payload_len == 0 else "" tx_udp = f"echo -n {test_string} | socat -t 2 " + \ - f"-u STDIN UDP:{cfg.baddr}:{port}" + f"-u STDIN UDP:{cfg.baddr}:{port}{tx_cmd_suffix}" with bkg(rx_udp, host=cfg.remote, exit_wait=True) as rnc: wait_port_listen(port, proto="udp", host=cfg.remote) @@ -329,6 +334,21 @@ def _test_xdp_native_tx(cfg, bpf_info, payload_lens): ksft_eq(stats[XDPStats.TX.value], expected_pkts, "TX stats mismatch") +def test_xdp_native_tx_sb(cfg): + """ + Tests the XDP_TX action for a single-buff case. + + Args: + cfg: Configuration object containing network settings. + """ + bpf_info = BPFProgInfo("xdp_prog", "xdp_native.bpf.o", "xdp", 1500) + + # Ensure there's enough room for an ETH / IP / UDP header + pkt_hdr_len = 42 if cfg.addr_ipver == "4" else 62 + + _test_xdp_native_tx(cfg, bpf_info, [0, 1500 // 2, 1500 - pkt_hdr_len]) + + def test_xdp_native_tx_mb(cfg): """ Tests the XDP_TX action for a multi-buff case. @@ -665,6 +685,7 @@ def main(): test_xdp_native_pass_mb, test_xdp_native_drop_sb, test_xdp_native_drop_mb, + test_xdp_native_tx_sb, test_xdp_native_tx_mb, test_xdp_native_adjst_tail_grow_data, test_xdp_native_adjst_tail_shrnk_data, From bbd885b193cc8a651e18eef74f0e094acbc802b8 Mon Sep 17 00:00:00 2001 From: Dimitri Daskalakis Date: Wed, 20 Aug 2025 18:40:23 -0700 Subject: [PATCH 3/3] selftests: drv-net: xdp: Validate single-buff XDP_TX in multi-buff mode Validate that drivers with multi-buff XDP programs properly reinitialize xdp_buff between packets. Signed-off-by: Dimitri Daskalakis Link: https://patch.msgid.link/20250821014023.1481662-4-dimitri.daskalakis1@gmail.com Signed-off-by: Jakub Kicinski --- tools/testing/selftests/drivers/net/xdp.py | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/drivers/net/xdp.py b/tools/testing/selftests/drivers/net/xdp.py index cea24c9b573e..35e9495cd506 100755 --- a/tools/testing/selftests/drivers/net/xdp.py +++ b/tools/testing/selftests/drivers/net/xdp.py @@ -358,7 +358,10 @@ def test_xdp_native_tx_mb(cfg): """ bpf_info = BPFProgInfo("xdp_prog_frags", "xdp_native.bpf.o", "xdp.frags", 9000) - _test_xdp_native_tx(cfg, bpf_info, [8000]) + # The first packet ensures we exercise the fragmented code path. + # And the subsequent 0-sized packet ensures the driver + # reinitializes xdp_buff correctly. + _test_xdp_native_tx(cfg, bpf_info, [8000, 0]) def _validate_res(res, offset_lst, pkt_sz_lst):