linux-kernel - [PATCH 5.10 084/289] selftests: mlxsw: Increase the tolerance of backlog buildup

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210517140308.013702785@linuxfoundation.org>
Date:   Mon, 17 May 2021 16:00:09 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Petr Machata <petrm@...dia.com>,
        Jiri Pirko <jiri@...dia.com>,
        "David S. Miller" <davem@...emloft.net>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.10 084/289] selftests: mlxsw: Increase the tolerance of backlog buildup

From: Petr Machata <petrm@...dia.com>

[ Upstream commit dda7f4fa55839baeb72ae040aeaf9ccf89d3e416 ]

The intention behind this test is to make sure that qdisc limit is
correctly projected to the HW. However, first, due to rounding in the
qdisc, and then in the driver, the number cannot actually be accurate. And
second, the approach to testing this is to oversubscribe the port with
traffic generated on the same switch. The actual backlog size therefore
fluctuates.

In practice, this test proved to be noisier than the rest, and spuriously
fails every now and then. Increase the tolerance to 10 % to avoid these
issues.

Signed-off-by: Petr Machata <petrm@...dia.com>
Acked-by: Jiri Pirko <jiri@...dia.com>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 tools/testing/selftests/drivers/net/mlxsw/sch_red_core.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/drivers/net/mlxsw/sch_red_core.sh b/tools/testing/selftests/drivers/net/mlxsw/sch_red_core.sh
index b0cb1aaffdda..33ddd01689be 100644
--- a/tools/testing/selftests/drivers/net/mlxsw/sch_red_core.sh
+++ b/tools/testing/selftests/drivers/net/mlxsw/sch_red_core.sh
@@ -507,8 +507,8 @@ do_red_test()
 	check_err $? "backlog $backlog / $limit Got $pct% marked packets, expected == 0."
 	local diff=$((limit - backlog))
 	pct=$((100 * diff / limit))
-	((0 <= pct && pct <= 5))
-	check_err $? "backlog $backlog / $limit expected <= 5% distance"
+	((0 <= pct && pct <= 10))
+	check_err $? "backlog $backlog / $limit expected <= 10% distance"
 	log_test "TC $((vlan - 10)): RED backlog > limit"
 
 	stop_traffic
-- 
2.30.2