Received-SPF: pass (google.com: domain of linux-kernel+bounces-172171-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) client-ip=147.75.80.249;
Precedence: bulk
MIME-Version: 1.0
References: <20240507-upstream-bpf-next-20240506-mptcp-subflow-test-v1-0-e2bcbdf49857@kernel.org>
 <20240507-upstream-bpf-next-20240506-mptcp-subflow-test-v1-2-e2bcbdf49857@kernel.org>
 <CAADnVQJ5-APFxMeGsUDSWBsiAbhJGivs=fBUapgYEFNHgnEVeA@mail.gmail.com> <d28dec16-9029-42f5-b979-a0f11656a991@kernel.org>
In-Reply-To: <d28dec16-9029-42f5-b979-a0f11656a991@kernel.org>
From: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Date: Tue, 7 May 2024 13:51:48 -0700
Message-ID: <CAADnVQJM73g9gTq3GxR-RMmpJPK3DGgzUTQiJXjz_B1G_4JAAw@mail.gmail.com>
Subject: Re: [PATCH bpf-next 2/4] selftests/bpf: Add RUN_MPTCP_TEST macro
To: Matthieu Baerts <matttbe@kernel.org>
Cc: MPTCP Upstream <mptcp@lists.linux.dev>, Mat Martineau <martineau@kernel.org>, 
	Geliang Tang <geliang@kernel.org>, Andrii Nakryiko <andrii@kernel.org>, 
	Eduard Zingerman <eddyz87@gmail.com>, Mykola Lysenko <mykolal@fb.com>, Alexei Starovoitov <ast@kernel.org>, 
	Daniel Borkmann <daniel@iogearbox.net>, Martin KaFai Lau <martin.lau@linux.dev>, Song Liu <song@kernel.org>, 
	Yonghong Song <yonghong.song@linux.dev>, John Fastabend <john.fastabend@gmail.com>, 
	KP Singh <kpsingh@kernel.org>, Stanislav Fomichev <sdf@google.com>, Hao Luo <haoluo@google.com>, 
	Jiri Olsa <jolsa@kernel.org>, Shuah Khan <shuah@kernel.org>, LKML <linux-kernel@vger.kernel.org>, 
	Network Development <netdev@vger.kernel.org>, bpf <bpf@vger.kernel.org>, 
	"open list:KERNEL SELFTEST FRAMEWORK" <linux-kselftest@vger.kernel.org>, Geliang Tang <tanggeliang@kylinos.cn>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Tue, May 7, 2024 at 9:02=E2=80=AFAM Matthieu Baerts <matttbe@kernel.org>=
 wrote:
>
> Hi Alexei,
>
> Thank you for the review!
>
> On 07/05/2024 16:44, Alexei Starovoitov wrote:
> > On Tue, May 7, 2024 at 3:53=E2=80=AFAM Matthieu Baerts (NGI0)
> > <matttbe@kernel.org> wrote:
> >>
> >> From: Geliang Tang <tanggeliang@kylinos.cn>
> >>
> >> Each MPTCP subtest tests test__start_subtest(suffix), then invokes
> >> test_suffix(). It makes sense to add a new macro RUN_MPTCP_TEST to
> >> simpolify the code.
> >>
> >> Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
> >> Reviewed-by: Mat Martineau <martineau@kernel.org>
> >> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
> >> ---
> >>  tools/testing/selftests/bpf/prog_tests/mptcp.c | 12 ++++++++----
> >>  1 file changed, 8 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/tools/testing/selftests/bpf/prog_tests/mptcp.c b/tools/te=
sting/selftests/bpf/prog_tests/mptcp.c
> >> index baf976a7a1dd..9d1b255bb654 100644
> >> --- a/tools/testing/selftests/bpf/prog_tests/mptcp.c
> >> +++ b/tools/testing/selftests/bpf/prog_tests/mptcp.c
> >> @@ -347,10 +347,14 @@ static void test_mptcpify(void)
> >>         close(cgroup_fd);
> >>  }
> >>
> >> +#define RUN_MPTCP_TEST(suffix)                                 \
> >> +do {                                                           \
> >> +       if (test__start_subtest(#suffix))                       \
> >> +               test_##suffix();                                \
> >> +} while (0)
> >
> > Please no.
> > Don't hide it behind macros.
>
> I understand, I'm personally not a big fan of hiding code being a macro
> too. This one saves only one line. Geliang added a few more tests in our
> tree [1], for a total of 9, so that's only saving 9 lines.
>
> Related to that, if you don't mind, Geliang also added another macro --
> MPTCP_SCHED_TEST -- for tests that are currently only in our tree [2]
> (not ready yet). We asked him to reduce the size of this macro to the
> minimum. We accepted it because it removed quite a lot of similar code
> with very small differences [3]. Do you think we should revert this
> modification too?

Yeah. Pls don't hide such things in macros.
Refactor into helper function in normal C.

But, what do you mean "in your tree" ?
That's your development tree and you plan to send all that
properly as patches to bpf-next someday?

>
> [1]
> https://github.com/multipath-tcp/mptcp_net-next/blob/4369d9cbd752e166961a=
c0db7f85886111606301/tools/testing/selftests/bpf/prog_tests/mptcp.c#L578-L5=
95
>
> [2]
> https://github.com/multipath-tcp/mptcp_net-next/blob/4369d9cbd752e166961a=
c0db7f85886111606301/tools/testing/selftests/bpf/prog_tests/mptcp.c#L559-L5=
76
>
> [3]
> https://lore.kernel.org/mptcp/cover.1713321357.git.tanggeliang@kylinos.cn=
/T/#m0b9c14f1cbae8653c6fd119f6b71d1797961d6ba
>
> Cheers,
> Matt
> --
> Sponsored by the NGI0 Core fund.
>