selftests: mlxsw: Increase the tolerance of backlog buildup
authorPetr Machata <petrm@nvidia.com>
Fri, 23 Apr 2021 12:19:47 +0000 (14:19 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 19 May 2021 08:12:59 +0000 (10:12 +0200)
commitdfa0e8461e99924a75cb0e03134475cf3b92c2a7
tree412d344bbddc42dbcd40e8329b3a738a14116317
parent99d9989ee53bd8c75d113c9b8039724ddec5a929
selftests: mlxsw: Increase the tolerance of backlog buildup

[ 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@nvidia.com>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
tools/testing/selftests/drivers/net/mlxsw/sch_red_core.sh