Create a topology with a host, and a router. The host (veth0) is in the
default namespace, and a network namespace is created for the router,
the peer veth1 is moved to the router netns. A dummy interface is added
inside the router netns, to simulate a network that has two neighbors.
An ECMP route to a virtual IP (vip) with the two neighbors as the next
hop is added.
The test uses perf stat to count the number of fib:fib_table_lookup
tracepoint hits for IPv4 and the number of fib6:fib6_table_lookup for
IPv6. The measured count is checked to be within 15% for the number of
packets received on veth1 in the router.
See diagram in the test for more information.
Suggested-by: Ido Schimmel <idosch@xxxxxxxxxx>
Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@xxxxxxxx>
---
.../testing/selftests/net/forwarding/Makefile | 1 +
tools/testing/selftests/net/forwarding/lib.sh | 5 +
.../net/forwarding/router_multipath_vip.sh | 255 ++++++++++++++++++
3 files changed, 261 insertions(+)
create mode 100755 tools/testing/selftests/net/forwarding/router_multipath_vip.sh
diff --git a/tools/testing/selftests/net/forwarding/Makefile b/tools/testing/selftests/net/forwarding/Makefile
index 770efbe24f0d..bf4e5745fd5c 100644
--- a/tools/testing/selftests/net/forwarding/Makefile
+++ b/tools/testing/selftests/net/forwarding/Makefile
@@ -70,6 +70,7 @@ TEST_PROGS = bridge_igmp.sh \
router_mpath_nh.sh \
router_multicast.sh \
router_multipath.sh \
+ router_multipath_vip.sh \
router_nh.sh \
router.sh \
router_vid_1.sh \
diff --git a/tools/testing/selftests/net/forwarding/lib.sh b/tools/testing/selftests/net/forwarding/lib.sh
index f69015bf2dea..75a7b138c399 100755
--- a/tools/testing/selftests/net/forwarding/lib.sh
+++ b/tools/testing/selftests/net/forwarding/lib.sh
@@ -787,6 +787,11 @@ link_stats_tx_packets_get()
link_stats_get $1 tx packets
}
+link_stats_rx_packets_get()
+{
+ link_stats_get $1 rx packets
+}
+
link_stats_rx_errors_get()
{
link_stats_get $1 rx errors
diff --git a/tools/testing/selftests/net/forwarding/router_multipath_vip.sh b/tools/testing/selftests/net/forwarding/router_multipath_vip.sh
new file mode 100755
index 000000000000..9aefebd8085c
--- /dev/null
+++ b/tools/testing/selftests/net/forwarding/router_multipath_vip.sh
@@ -0,0 +1,255 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# +--------------------+
+# | H1 |
+# | |
+# | $h1 + |
+# | 192.0.2.2/28 | |
+# | 2001:db8:1::2/64 | |
+# | | |
+# +------------------|-+
+# |
+# +------------------|-----------------------+ +----------------------+
+# | SW | | | |
+# | (netns ns-r1) | | | + $neigh1 |
+# | $rp1 + | | 192.0.2.18/28 |
+# | 192.0.2.1/28 | | 2001:db8:2::2/64 |
+# | 2001:db8:1::1/64 + vip | | |
+# | 198.51.100.0/24 | +----------------------+
+# | 2001:db8:3::/64 | | |
+# | | | + $neigh2 |
+# | | | 192.0.2.19/28 |
+# | | | 2001:db8:2::3/64 |
+# | | | |
+# +------------------------------------------+ +----------------------+
+
+ALL_TESTS="multipath_test"
+NUM_NETIFS=2
+source lib.sh
+
+ns_create()
+{
+ local ns="$1"
+
+ ip netns add $ns
+
+ in_ns $ns ip link set dev lo up
+ in_ns $ns forwarding_enable
+}
+
+ns_destroy()
+{
+ local ns="$1"
+
+ ip netns del $ns &> /dev/null
+}
+
+h1_create()
+{
+ ip link set dev $h1 up
+ ip address add 192.0.2.2/28 dev $h1
+ ip address add 2001:db8:1::2/64 dev $h1
+
+ ethtool -K $h1 tcp-segmentation-offload off
+}
+
+h1_destroy()
+{
+ ethtool -K $h1 tcp-segmentation-offload on
+
+ ip address del 2001:db8:1::2/64 dev $h1
+ ip address del 192.0.2.2/28 dev $h1
+ ip link set dev $h1 down
+}
+
+router_create()
+{
+ ns="ns-r1"
+ dummy="dum1"
+
+ echo 20000 > /sys/class/net/$rp1/gro_flush_timeout
+ echo 1 > /sys/class/net/$rp1/napi_defer_hard_irqs
+ ethtool -K $rp1 generic-receive-offload on
+
+ ns_create $ns
+ ip link set dev $rp1 netns $ns
+
+ ip -n $ns link set dev $rp1 up
+ ip -n $ns address add dev $rp1 192.0.2.1/28
+
+ ip -n $ns link add name $dummy up type dummy
+ ip -n $ns address add 192.0.2.17/28 dev $dummy
+ ip -n $ns address add 2001:db8:2::1/64 dev $dummy
+
+ ip -n $ns neigh add 192.0.2.18 lladdr 00:11:22:33:44:55 nud perm dev $dummy
+ ip -n $ns neigh add 192.0.2.19 lladdr 00:aa:bb:cc:dd:ee nud perm dev $dummy
+ ip -n $ns neigh add 2001:db8:2::2 lladdr 00:11:22:33:44:55 nud perm dev $dummy
+ ip -n $ns neigh add 2001:db8:2::3 lladdr 00:aa:bb:cc:dd:ee nud perm dev $dummy
+
+ ip -n $ns route add 198.51.100.0/24 \
+ nexthop via 192.0.2.18 \
+ nexthop via 192.0.2.19
+
+ ip -n $ns route add 2001:db8:3::/64 \
+ nexthop via 2001:db8:2::2 \
+ nexthop via 2001:db8:2::3
+}
+
+router_destroy()
+{
+ ns="ns-r1"
+ dummy="dum1"
+
+ ip -n $ns link del dev $dummy
+
+ ip -n $ns address del dev $rp1 192.0.2.1/28
+ ip -n $ns link set dev $rp1 down
+ ip -n $ns link set dev $rp1 netns 1
+
+ ns_destroy $ns
+
+ echo 0 > /sys/class/net/$rp1/gro_flush_timeout
+ echo 0 > /sys/class/net/$rp1/napi_defer_hard_irqs
+ ethtool -K $rp1 generic-receive-offload off
+}
+
+perf_stat()
+{
+ local tracepoint="$1"
+ local cmd="$2"
+ local out="$3"
+
+ perf stat -o $out -j $tracepoint -a &
+ perf_stat_pid=$!
+
+ $cmd
+
+ kill -SIGINT $perf_stat_pid && wait $perf_stat_pid
+}
+
+perf_evaluate()
+{
+ local desc="$1"
+ local expected=$2
+ local perf_output="$3"
+
+ RET=0
+ measured=$(tail -n 1 $perf_output | jq '.["counter-value"] | tonumber | floor')
+
+ diff=$(echo $expected - $measured | bc -l)
+ diff=${diff#-}
+
+ test "$(echo "$diff / $expected > 0.15" | bc -l)" -eq 0
+ check_err $? "Too large discrepancy between expected and measured fib lookup counts"
+ log_test "$desc"
+ log_info "Expected count $expected Measured count $measured"
+}
+
+run_test_and_check_tpv4()
+{
+ local src_ip="$1"
+ local dst_ip="$2"
+ local t0_rp1 t1_rp1
+ local expected
+
+ # Transmit multiple flows from h1 to vip and check that fib lookup
+ # tracepoint is hit for each packet.
+ in_ns ns-r1 sysctl_set net.ipv4.fib_multipath_hash_policy 1
+
+ t0_rp1=$(in_ns ns-r1 link_stats_rx_packets_get $rp1)
+
+ smac=$(mac_get $h1)
+ dmac=$(in_ns ns-r1 mac_get $rp1)
+ cmd="$MZ $h1 -q -p 64 -a $smac -b $dmac -A $src_ip -B $dst_ip
+ -t udp 'sp=1024,dp=1024-65535'"
+
+ perf_output=$(mktemp)
+ perf_stat "-e fib:fib_table_lookup" "$cmd" "$perf_output"
+
+ t1_rp1=$(in_ns ns-r1 link_stats_rx_packets_get $rp1)
+ expected="$(echo "$t1_rp1 - $t0_rp1" | bc -l)"
+
+ perf_evaluate "IPv4 multipath: fib_table_lookup" $expected "$perf_output"
+ rm $perf_output
+
+ in_ns ns-r1 sysctl_restore net.ipv4.fib_multipath_hash_policy
+}
+
+run_test_and_check_tpv6()
+{
+ local src_ip="$1"
+ local dst_ip="$2"
+ local t0_rp1 t1_rp1
+ local expected
+
+ # Transmit multiple flows from h1 to vip and check that fib lookup
+ # tracepoint is hit for each packet.
+ in_ns ns-r1 sysctl_set net.ipv4.fib_multipath_hash_policy 1
+
+ t0_rp1=$(in_ns ns-r1 link_stats_rx_packets_get $rp1)
+
+ smac=$(mac_get $h1)
+ dmac=$(in_ns ns-r1 mac_get $rp1)
+ cmd="$MZ $h1 -6 -q -p 64 -a $smac -b $dmac -A $src_ip -B $dst_ip
+ -t udp 'sp=1024,dp=1024-65535'"
+
+ perf_output=$(mktemp)
+ perf_stat "-e fib6:fib6_table_lookup" "$cmd" "$perf_output"
+
+ # fib6_table_lookup is called twice for each packet, for
+ # RT6_TABLE_LOCAL and RT6_TABLE_MAIN
+ t1_rp1=$(in_ns ns-r1 link_stats_rx_packets_get $rp1)
+ expected="$(echo "2*($t1_rp1 - $t0_rp1)" | bc -l)"
+
+ perf_evaluate "IPv6 multipath: fib6_table_lookup" $expected "$perf_output"
+ rm $perf_output
+
+ in_ns ns-r1 sysctl_restore net.ipv4.fib_multipath_hash_policy
+}
+
+multipath_test()
+{
+ log_info "Running multipath tests"
+ run_test_and_check_tpv4 "192.0.2.2" "198.51.100.1"
+ run_test_and_check_tpv6 "2001:db8:1::2" "2001:db8:3::1"
+}
+
+setup_prepare()
+{
+ h1=${NETIFS[p1]}
+ rp1=${NETIFS[p2]}
+
+
+ h1_create
+ router_create
+}
+
+setup_wait()
+{
+ h1=${NETIFS[p1]}
+ rp1=${NETIFS[p2]}
+
+ setup_wait_dev $h1
+ in_ns ns-r1 setup_wait_dev $rp1
+
+ # Make sure links are ready.
+ sleep $WAIT_TIME
+}
+
+cleanup()
+{
+ pre_cleanup
+
+ router_destroy
+ h1_destroy
+}
+
+trap cleanup EXIT
+
+setup_prepare
+setup_wait
+
+tests_run
+
+exit $EXIT_STATUS
--
2.34.1
