From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout-04.galae.net (smtpout-04.galae.net [185.171.202.116]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8DE694D37B1 for ; Wed, 14 Oct 2026 08:55:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.171.202.116 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791968152; cv=none; b=cRfzug2o0iPvFIxdmOJFBB7ED8LntTWSDAWE7dw9OYlNMrJV+JGDhlG0Fpa7RWJ/7y6m3fBvQUrTv5PkANHvD0j5xlyIq6I+4Y5TnIq8vtP4V3RPDEUK0a7c0dNzLGuEBOrcKg8UauMZPAY4bqD774PZy57E+LrEPc5FYcps0y4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791968152; c=relaxed/simple; bh=lm+iu5n5093iTPvAm4b/0xhVRpxk5O455f+QlfZJK5A=; h=Mime-Version:Content-Type:Date:Message-Id:Subject:Cc:From:To: References:In-Reply-To; b=lJSImzSvdWsNqjPIIKl1gCFTSW3kgC2jMNgadQtJlD/iC4bS8AexsHDHtOYOXCkiIxDavmaILBGAW8I6uYCxwE2b8IBt6Akk1fCmEPKGcxuR3HuPniw6F0wtf5MITDNdO+ScNjJzNNU4k9zAKMdrlvOZUX6MuHZOeFeLiCtGdLE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=lYtlYW6n; arc=none smtp.client-ip=185.171.202.116 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="lYtlYW6n" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-04.galae.net (Postfix) with ESMTPS id 5E1DDC63440; Wed, 14 Oct 2026 08:56:42 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 74C7C60368; Wed, 14 Oct 2026 08:55:46 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id B33A2103286A7; Wed, 14 Oct 2026 10:55:41 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1791968145; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=Fr2cUfVwHpS0gQAAl2BplVTlMggZNGW5Syq9UOyYYuE=; b=lYtlYW6nORzpeaJOtJht7lLWf43BPtnqtMLzsgVNyfMHTq9m+bIgkUzR6OZeiBVEA8KlxQ LiL2EIB/WOTrDWmeU7IYhX8RpwMZnd+ZhjTBG4SJFWBV7porEQiBKbh96pTI/ab8J+5a45 Gnl9A3I7/SZGYV52CFkwdIUG3HV1eAQFL5ZEDquFaDGmdPh5diiwGnnoK2zoQGewvbOVMj KoaKHp5F1xijoWOX0grGfWVojZ0yspqKBSJZVxN35qF9uDXKnzmlZR8GuRFBKsZUATdrlN 5jxYvnVESKhByR9tzm+w+qGICFxLveCsGd+xVFqpFzppzoXO6dvjIgUn9sMXTQ== Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Wed, 14 Oct 2026 10:55:40 +0200 Message-Id: Subject: Re: [PATCH bpf-next] selftests/bpf: Run tc_edt serially Cc: , , From: =?utf-8?q?Alexis_Lothor=C3=A9?= To: "Qiliang Yuan" , "Alexei Starovoitov" , "Daniel Borkmann" , "Andrii Nakryiko" , "Eduard Zingerman" , "Kumar Kartikeya Dwivedi" , "Martin KaFai Lau" , "Song Liu" , "Yonghong Song" , "Jiri Olsa" , "Emil Tsalapatis" , "Ihor Solodrai" , "Shuah Khan" , =?utf-8?b?QWxleGlzIExvdGhvcsOpIChlQlBGIEZvdW5kYXRpb24p?= X-Mailer: aerc 0.22.0-0-gc2f86b7abde3 References: <20261009-selftests-bpf-tc-edt-serial-v1-1-f72e045f2465@gmail.com> In-Reply-To: <20261009-selftests-bpf-tc-edt-serial-v1-1-f72e045f2465@gmail.com> X-Last-TLS-Session-Version: TLSv1.3 Hi Qiliang, On Fri Oct 9, 2026 at 3:50 AM CEST, Qiliang Yuan wrote: > tc_edt shapes the traffic of a TCP connection between two netns to > 5Mbps with a BPF program, and checks that the rate it measures from the > userspace sender and receiver is within 2% of the target. > > The measured time includes the time the sender and the receiver take to > run. When test_progs runs other tests in parallel, the sender and the > receiver compete with those for the CPUs, the transfer takes longer, > and the measured rate falls outside of the 2% margin. > > Make tc_edt a serial test. > > Fixes: b0f82e7ab6fb ("selftests/bpf: integrate test_tc_edt into test_prog= s") > Signed-off-by: Qiliang Yuan I don't know how to feel about the proposed fix. As a test involving bandwith measurement, I get that such things could happen, but: - I did not see this failure in the recent CI runs (but I could have missed it) - if you see it in your setup, how sure are we that it is due to high CPU usage ? I guess it is very likely, but worth asking - any idea about how much we are missing the 2% margin ? If this is only by a little, I would rather increase the margin and keep the tests parallel, there's not much point being too restrictive on the target bandwith, if we get something close enough, this is a good proof that the BPF rate limiter is triggered and running correctly Thanks, Alexis > --- > tools/testing/selftests/bpf/prog_tests/test_tc_edt.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/bpf/prog_tests/test_tc_edt.c b/tools= /testing/selftests/bpf/prog_tests/test_tc_edt.c > index 462512fb191f1..1e82d88c987a7 100644 > --- a/tools/testing/selftests/bpf/prog_tests/test_tc_edt.c > +++ b/tools/testing/selftests/bpf/prog_tests/test_tc_edt.c > @@ -127,7 +127,7 @@ static void run_test(void) > "rate error is lower than threshold"); > } > =20 > -void test_tc_edt(void) > +void serial_test_tc_edt(void) > { > struct test_tc_edt *skel; > =20 > > --- > base-commit: e1d84a37cba984388988d2f1ddc84561413f0db2 > change-id: 20261009-selftests-bpf-tc-edt-serial-9c65af71f845 > > Best regards, --=20 Alexis Lothor=C3=A9, Bootlin Embedded Linux and Kernel engineering https://bootlin.com