Re: [PATCH net-next v2 4/4] selftests: drv-net: Test that NAPI ID is non-zero

From: Jakub Kicinski
Date: Thu Apr 17 2025 - 09:46:43 EST


On Thu, 17 Apr 2025 01:32:42 +0000 Joe Damato wrote:
> Test that the SO_INCOMING_NAPI_ID of a network file descriptor is
> non-zero. This ensures that either the core networking stack or, in some
> cases like netdevsim, the driver correctly sets the NAPI ID.
>
> Signed-off-by: Joe Damato <jdamato@xxxxxxxxxx>
> ---
> .../testing/selftests/drivers/net/.gitignore | 1 +
> tools/testing/selftests/drivers/net/Makefile | 6 +-
> .../testing/selftests/drivers/net/napi_id.py | 24 ++++++
> .../selftests/drivers/net/napi_id_helper.c | 83 +++++++++++++++++++
> 4 files changed, 113 insertions(+), 1 deletion(-)
> create mode 100755 tools/testing/selftests/drivers/net/napi_id.py
> create mode 100644 tools/testing/selftests/drivers/net/napi_id_helper.c
>
> diff --git a/tools/testing/selftests/drivers/net/.gitignore b/tools/testing/selftests/drivers/net/.gitignore
> index ec746f374e85..71bd7d651233 100644
> --- a/tools/testing/selftests/drivers/net/.gitignore
> +++ b/tools/testing/selftests/drivers/net/.gitignore
> @@ -1,2 +1,3 @@
> # SPDX-License-Identifier: GPL-2.0-only
> xdp_helper
> +napi_id_helper

sort alphabetically, pls

> diff --git a/tools/testing/selftests/drivers/net/Makefile b/tools/testing/selftests/drivers/net/Makefile
> index 0c95bd944d56..47247c2ef948 100644
> --- a/tools/testing/selftests/drivers/net/Makefile
> +++ b/tools/testing/selftests/drivers/net/Makefile
> @@ -6,9 +6,13 @@ TEST_INCLUDES := $(wildcard lib/py/*.py) \
> ../../net/net_helper.sh \
> ../../net/lib.sh \
>
> -TEST_GEN_FILES := xdp_helper
> +TEST_GEN_FILES := \
> + napi_id_helper \
> + xdp_helper \

like you did here

> +# end of TEST_GEN_FILES
>
> TEST_PROGS := \
> + napi_id.py \
> netcons_basic.sh \
> netcons_fragmented_msg.sh \
> netcons_overflow.sh \
> diff --git a/tools/testing/selftests/drivers/net/napi_id.py b/tools/testing/selftests/drivers/net/napi_id.py
> new file mode 100755
> index 000000000000..aee6f90be49b
> --- /dev/null
> +++ b/tools/testing/selftests/drivers/net/napi_id.py
> @@ -0,0 +1,24 @@
> +#!/usr/bin/env python3
> +# SPDX-License-Identifier: GPL-2.0
> +
> +from lib.py import ksft_run, ksft_exit
> +from lib.py import ksft_eq, NetDrvEpEnv
> +from lib.py import bkg, cmd, rand_port, NetNSEnter
> +
> +def test_napi_id(cfg) -> None:
> + port = rand_port()
> + listen_cmd = f'{cfg.test_dir / "napi_id_helper"} {cfg.addr_v['4']} {port}'

you need to deploy, in case test is running with a real remote machine
and the binary has to be copied over:

bin_remote = cfg.remote.deploy(cfg.test_dir / "napi_id_helper")
listen_cmd = f'{bin_remote} {cfg.addr_v['4']} {port}'

> + with bkg(listen_cmd, ksft_wait=3) as server:
> + with NetNSEnter('net', '/proc/self/ns/'):
> + cmd(f"echo a | socat - TCP:{cfg.addr_v['4']}:{port}", host=cfg.remote, shell=True)

Like Xiao Liang said, just host=cfg.remote should work.

> + ksft_eq(0, server.ret)
> +