Re: [PATCH net-next v4 02/10] selftests: net: add helpers for running a command on other targets

Petr Machata
2026-03-30T11:27:08Z

Ioana Ciornei <ioana.ciornei@nxp.com> writes:

> Add a couple of helpers which can be used by tests which need to run a
> specific bash command on a different target than the local system, be it
> either another netns or a remote system accessible through ssh.
>
> The __run_on() function is passed through $1 the target on which the
> command should be executed while run_on() is passed the name of the
> interface that is then used to retrieve the target from the TARGETS
> array.
>
> Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
> ---
> Changes in v4:
> - reworked the helpers so that no global variable is used and
> information is passed only through parameters
> Changes in v3:
> - s/TARGET/CUR_TARGET
> - always fallback on running a command locally when either TARGETS is
> not declared or there is no entry for a specific interface
> Changes in v2:
> - patch is new
>
> tools/testing/selftests/net/lib.sh | 38 ++++++++++++++++++++++++++++++
> 1 file changed, 38 insertions(+)
>
> diff --git a/tools/testing/selftests/net/lib.sh b/tools/testing/selftests/net/lib.sh
> index b40694573f4c..6c0d613a4de5 100644
> --- a/tools/testing/selftests/net/lib.sh
> +++ b/tools/testing/selftests/net/lib.sh
> @@ -670,3 +670,41 @@ cmd_jq()
> # return success only in case of non-empty output
> [ ! -z "$output" ]
> }
> +
> +__run_on()
> +{
> + local target=$1; shift
> + local type args
> +
> + IFS=':' read -r type args <<< "$target"
> +
> + case "$type" in
> + netns)
> + # Execute command in network namespace
> + # args contains the namespace name
> + ip netns exec "$args" "$@"
> + ;;
> + ssh)
> + # Execute command via SSH args contains user@host
> + ssh -n "$args" "$@"
> + ;;
> + local|*)
> + # Execute command locally. This is also the fallback
> + # case for when the interface's target is not found in
> + # the TARGETS array.
> + "$@"
> + ;;
> + esac
> +}
> +
> +run_on()
> +{
> + local iface=$1; shift
> + local target="local:"
> +
> + if declare -p TARGETS &>/dev/null; then
> + target="${TARGETS[$iface]}"

So I think Jakub's runs fail because there's a shell export somewhere
that gets inherited through make to the launched test. I guess it would
be enough for the test to validate that TARGETS is an array, because
those don't get inherited.

Is there a reason not to reuse DRIVER_TEST_CONFORMANT as a tell though?

> + fi
> +
> + __run_on "$target" "$@"
> +}

Does the latter helper need to be in net/lib.sh? Since it uses TARGETS,
which are a forwarding/lib.sh concept, it seems misplaced there.