Subject: Re: [PATCH nf-next 6/6] selftests: add a selftest for big tcp

From: Aaron Conole <[email-masked]>
Date: Tue, 07 Mar 2023 13:31:10 -0500

Xin Long <[email-masked]> writes:

> This test runs on the client-router-server topo, and monitors the traffic
> on the RX devices of router and server while sending BIG TCP packets with
> netperf from client to server. Meanwhile, it changes 'tso' on the TX devs
> and 'gro' on the RX devs. Then it checks if any BIG TCP packets appears
> on the RX devs with 'ip/ip6tables -m length ! --length 0:65535' for each
> case.
>
> Note that we also add tc action ct in link1 ingress to cover the ipv6
> jumbo packets process in nf_ct_skb_network_trim() of nf_conntrack_ovs.
>
> Signed-off-by: Xin Long <[email-masked]>
> ---

LGTM - just one question

Reviewed-by: Aaron Conole <[email-masked]>

>  tools/testing/selftests/net/Makefile   |   1 +
>  tools/testing/selftests/net/big_tcp.sh | 180 +++++++++++++++++++++++++
>  2 files changed, 181 insertions(+)
>  create mode 100755 tools/testing/selftests/net/big_tcp.sh
>
> diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
> index 6cd8993454d7..099741290184 100644
> --- a/tools/testing/selftests/net/Makefile
> +++ b/tools/testing/selftests/net/Makefile
> @@ -48,6 +48,7 @@ TEST_PROGS += l2_tos_ttl_inherit.sh
>  TEST_PROGS += bind_bhash.sh
>  TEST_PROGS += ip_local_port_range.sh
>  TEST_PROGS += rps_default_mask.sh
> +TEST_PROGS += big_tcp.sh
>  TEST_PROGS_EXTENDED := in_netns.sh setup_loopback.sh setup_veth.sh
>  TEST_PROGS_EXTENDED += toeplitz_client.sh toeplitz.sh
>  TEST_GEN_FILES =  socket nettest
> diff --git a/tools/testing/selftests/net/big_tcp.sh b/tools/testing/selftests/net/big_tcp.sh
> new file mode 100755
> index 000000000000..cde9a91c4797
> --- /dev/null
> +++ b/tools/testing/selftests/net/big_tcp.sh
> @@ -0,0 +1,180 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# Testing For IPv4 and IPv6 BIG TCP.
> +# TOPO: CLIENT_NS (link0)<--->(link1) ROUTER_NS (link2)<--->(link3) SERVER_NS
> +
> +CLIENT_NS=$(mktemp -u client-XXXXXXXX)
> +CLIENT_IP4="198.51.100.1"
> +CLIENT_IP6="2001:db8:1::1"
> +
> +SERVER_NS=$(mktemp -u server-XXXXXXXX)
> +SERVER_IP4="203.0.113.1"
> +SERVER_IP6="2001:db8:2::1"
> +
> +ROUTER_NS=$(mktemp -u router-XXXXXXXX)
> +SERVER_GW4="203.0.113.2"
> +CLIENT_GW4="198.51.100.2"
> +SERVER_GW6="2001:db8:2::2"
> +CLIENT_GW6="2001:db8:1::2"
> +
> +MAX_SIZE=128000
> +CHK_SIZE=65535
> +
> +# Kselftest framework requirement - SKIP code is 4.
> +ksft_skip=4
> +
> +setup() {
> +	ip netns add $CLIENT_NS
> +	ip netns add $SERVER_NS
> +	ip netns add $ROUTER_NS
> +	ip -net $ROUTER_NS link add link1 type veth peer name link0 netns $CLIENT_NS
> +	ip -net $ROUTER_NS link add link2 type veth peer name link3 netns $SERVER_NS
> +
> +	ip -net $CLIENT_NS link set link0 up
> +	ip -net $CLIENT_NS link set link0 mtu 1442
> +	ip -net $CLIENT_NS addr add $CLIENT_IP4/24 dev link0
> +	ip -net $CLIENT_NS addr add $CLIENT_IP6/64 dev link0 nodad
> +	ip -net $CLIENT_NS route add $SERVER_IP4 dev link0 via $CLIENT_GW4
> +	ip -net $CLIENT_NS route add $SERVER_IP6 dev link0 via $CLIENT_GW6
> +	ip -net $CLIENT_NS link set dev link0 \
> +		gro_ipv4_max_size $MAX_SIZE gso_ipv4_max_size $MAX_SIZE
> +	ip -net $CLIENT_NS link set dev link0 \
> +		gro_max_size $MAX_SIZE gso_max_size $MAX_SIZE
> +	ip net exec $CLIENT_NS sysctl -wq net.ipv4.tcp_window_scaling=10
> +
> +	ip -net $ROUTER_NS link set link1 up
> +	ip -net $ROUTER_NS link set link2 up
> +	ip -net $ROUTER_NS addr add $CLIENT_GW4/24 dev link1
> +	ip -net $ROUTER_NS addr add $CLIENT_GW6/64 dev link1 nodad
> +	ip -net $ROUTER_NS addr add $SERVER_GW4/24 dev link2
> +	ip -net $ROUTER_NS addr add $SERVER_GW6/64 dev link2 nodad
> +	ip -net $ROUTER_NS link set dev link1 \
> +		gro_ipv4_max_size $MAX_SIZE gso_ipv4_max_size $MAX_SIZE
> +	ip -net $ROUTER_NS link set dev link2 \
> +		gro_ipv4_max_size $MAX_SIZE gso_ipv4_max_size $MAX_SIZE
> +	ip -net $ROUTER_NS link set dev link1 \
> +		gro_max_size $MAX_SIZE gso_max_size $MAX_SIZE
> +	ip -net $ROUTER_NS link set dev link2 \
> +		gro_max_size $MAX_SIZE gso_max_size $MAX_SIZE
> +	# test for nf_ct_skb_network_trim in nf_conntrack_ovs used by TC ct action.
> +	ip net exec $ROUTER_NS tc qdisc add dev link1 ingress
> +	ip net exec $ROUTER_NS tc filter add dev link1 ingress \
> +		proto ip flower ip_proto tcp action ct
> +	ip net exec $ROUTER_NS tc filter add dev link1 ingress \
> +		proto ipv6 flower ip_proto tcp action ct
> +	ip net exec $ROUTER_NS sysctl -wq net.ipv4.ip_forward=1
> +	ip net exec $ROUTER_NS sysctl -wq net.ipv6.conf.all.forwarding=1
> +
> +	ip -net $SERVER_NS link set link3 up
> +	ip -net $SERVER_NS addr add $SERVER_IP4/24 dev link3
> +	ip -net $SERVER_NS addr add $SERVER_IP6/64 dev link3 nodad
> +	ip -net $SERVER_NS route add $CLIENT_IP4 dev link3 via $SERVER_GW4
> +	ip -net $SERVER_NS route add $CLIENT_IP6 dev link3 via $SERVER_GW6
> +	ip -net $SERVER_NS link set dev link3 \
> +		gro_ipv4_max_size $MAX_SIZE gso_ipv4_max_size $MAX_SIZE
> +	ip -net $SERVER_NS link set dev link3 \
> +		gro_max_size $MAX_SIZE gso_max_size $MAX_SIZE
> +	ip net exec $SERVER_NS sysctl -wq net.ipv4.tcp_window_scaling=10
> +	ip net exec $SERVER_NS netserver 2>&1 >/dev/null
> +}
> +
> +cleanup() {
> +	ip net exec $SERVER_NS pkill netserver
> +	ip -net $ROUTER_NS link del link1
> +	ip -net $ROUTER_NS link del link2
> +	ip netns del "$CLIENT_NS"
> +	ip netns del "$SERVER_NS"
> +	ip netns del "$ROUTER_NS"
> +}
> +
> +start_counter() {
> +	local ipt="iptables"
> +	local iface=$1
> +	local netns=$2
> +
> +	[ "$NF" = "6" ] && ipt="ip6tables"
> +	ip net exec $netns $ipt -t raw -A PREROUTING -i $iface \
> +		-m length ! --length 0:$CHK_SIZE -j ACCEPT
> +}
> +
> +check_counter() {
> +	local ipt="iptables"
> +	local iface=$1
> +	local netns=$2
> +
> +	[ "$NF" = "6" ] && ipt="ip6tables"
> +	test `ip net exec $netns $ipt -t raw -L -v |grep $iface | awk '{print $1}'` != "0"
> +}
> +
> +stop_counter() {
> +	local ipt="iptables"
> +	local iface=$1
> +	local netns=$2
> +
> +	[ "$NF" = "6" ] && ipt="ip6tables"
> +	ip net exec $netns $ipt -t raw -D PREROUTING -i $iface \
> +		-m length ! --length 0:$CHK_SIZE -j ACCEPT
> +}
> +
> +do_netperf() {
> +	local serip=$SERVER_IP4
> +	local netns=$1
> +
> +	[ "$NF" = "6" ] && serip=$SERVER_IP6
> +	ip net exec $netns netperf -$NF -t TCP_STREAM -H $serip 2>&1 >/dev/null
> +}
> +
> +do_test() {
> +	local cli_tso=$1
> +	local gw_gro=$2
> +	local gw_tso=$3
> +	local ser_gro=$4
> +	local ret="PASS"
> +
> +	ip net exec $CLIENT_NS ethtool -K link0 tso $cli_tso
> +	ip net exec $ROUTER_NS ethtool -K link1 gro $gw_gro
> +	ip net exec $ROUTER_NS ethtool -K link2 tso $gw_tso
> +	ip net exec $SERVER_NS ethtool -K link3 gro $ser_gro
> +
> +	start_counter link1 $ROUTER_NS
> +	start_counter link3 $SERVER_NS
> +	do_netperf $CLIENT_NS
> +
> +	if check_counter link1 $ROUTER_NS; then
> +		check_counter link3 $SERVER_NS || ret="FAIL_on_link3"
> +	else
> +		ret="FAIL_on_link1"
> +	fi
> +
> +	stop_counter link1 $ROUTER_NS
> +	stop_counter link3 $SERVER_NS
> +	printf "%-9s %-8s %-8s %-8s: [%s]\n" \
> +		$cli_tso $gw_gro $gw_tso $ser_gro $ret
> +	test $ret = "PASS"
> +}
> +
> +testup() {
> +	echo "CLI GSO | GW GRO | GW GSO | SER GRO" && \
> +	do_test "on"  "on"  "on"  "on"  && \
> +	do_test "on"  "off" "on"  "off" && \
> +	do_test "off" "on"  "on"  "on"  && \
> +	do_test "on"  "on"  "off" "on"  && \
> +	do_test "off" "on"  "off" "on"
> +}
> +
> +if ! netperf -V &> /dev/null; then

Is it ever possible that we get netperf without netserver?

> +	echo "SKIP: Could not run test without netperf tool"
> +	exit $ksft_skip
> +fi
> +
> +if ! ip link help 2>&1 | grep gso_ipv4_max_size &> /dev/null; then
> +	echo "SKIP: Could not run test without gso/gro_ipv4_max_size supported in ip-link"
> +	exit $ksft_skip
> +fi
> +
> +trap cleanup EXIT
> +setup && echo "Testing for BIG TCP:" && \
> +NF=4 testup && echo "***v4 Tests Done***" && \
> +NF=6 testup && echo "***v6 Tests Done***"
> +exit $?