Commit 7049166e authored by Petr Machata's avatar Petr Machata Committed by Jakub Kicinski
Browse files

selftests: mlxsw: sch_red_core: Send more packets for drop tests 



This test works by injecting into a port with a maxed-out queue a couple
packets and checks if a corresponding number of packets were dropped. This
has worked well on Spectrum<4, but on Spectrum-4 it has been noisy. This
is in line with the observation that on Spectrum-4, queue size tends to
fluctuate more. A handful of packets could then still be accepted to the
queue even though it was nominally full just recently.

In order to accommodate this behavior, send many more packets. The buffer
can fit N extra packets, but not N% packets. This therefore allows us to
set wider absolute margins, while actually narrowing them relatively.

Signed-off-by: default avatarPetr Machata <petrm@nvidia.com>
Reviewed-by: default avatarIdo Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/abc869b9f6003d400d6293ddd5edb2f4517f44d5.1728316370.git.petrm@nvidia.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 787f148c

tools/testing/selftests/drivers/net/mlxsw/sch_red_core.sh

+9 −7
Original line number Diff line number Diff line
@@ -653,20 +653,22 @@ do_drop_test() 
	build_backlog $vlan $((3 * limit / 2)) udp >/dev/null



	base=$($fetch_counter)

	send_packets $vlan udp 11

	send_packets $vlan udp 100



	now=$(busywait 1100 until_counter_is ">= $((base + 10))" $fetch_counter)

	check_err $? "Dropped packets not observed: 11 expected, $((now - base)) seen"

	now=$(busywait 1100 until_counter_is ">= $((base + 95))" $fetch_counter)

	check_err $? "${trigger}ped packets not observed: 100 expected, $((now - base)) seen"



	# When no extra traffic is injected, there should be no mirroring.

	busywait 1100 until_counter_is ">= $((base + 20))" $fetch_counter >/dev/null

	busywait 1100 until_counter_is ">= $((base + 110))" \

		 $fetch_counter >/dev/null

	check_fail $? "Spurious packets observed"



	# When the rule is uninstalled, there should be no mirroring.

	qevent_rule_uninstall_$subtest

	send_packets $vlan udp 11

	busywait 1100 until_counter_is ">= $((base + 20))" $fetch_counter >/dev/null

	check_fail $? "Spurious packets observed after uninstall"

	send_packets $vlan udp 100

	now=$(busywait 1100 until_counter_is ">= $((base + 110))" \

		       $fetch_counter)

	check_fail $? "$((now - base)) spurious packets observed after uninstall"



	log_test "TC $((vlan - 10)): ${trigger}ped packets $subtest'd"