selftests: forwarding: Test IPv4 weighted nexthops

Use different weights for the multipath route configured on the first
router and check that the different flows generated by the first host
are distributed according to the provided weights.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/tools/testing/selftests/net/forwarding/lib.sh b/tools/testing/selftests/net/forwarding/lib.sh
index 962153b7181bb1f2546d327ba0de4d91bfc2c83f..6866f4a4bc4e2ef9001973227f5b656b7e62a3dd 100644 (file)
--- a/tools/testing/selftests/net/forwarding/lib.sh
+++ b/tools/testing/selftests/net/forwarding/lib.sh
@@ -113,6 +113,13 @@ log_test()
        return 0
 }
 
+log_info()
+{
+       local msg=$1
+
+       echo "INFO: $msg"
+}
+
 setup_wait()
 {
        for i in $(eval echo {1..$NUM_NETIFS}); do
@@ -256,6 +263,13 @@ master_name_get()
        ip -j link show dev $if_name | jq -r '.[]["master"]'
 }
 
+link_stats_tx_packets_get()
+{
+       local if_name=$1
+
+       ip -j -s link show dev $if_name | jq '.[]["stats64"]["tx"]["packets"]'
+}
+
 bridge_ageing_time_get()
 {
        local bridge=$1

diff --git a/tools/testing/selftests/net/forwarding/router_multipath.sh b/tools/testing/selftests/net/forwarding/router_multipath.sh
index 86d189b42e9bcc30612a0f43756650bac719e9a2..5b425dffb5d0001c061ed26f046a71c679d7fe06 100755 (executable)
--- a/tools/testing/selftests/net/forwarding/router_multipath.sh
+++ b/tools/testing/selftests/net/forwarding/router_multipath.sh
@@ -158,6 +158,82 @@ router2_destroy()
        vrf_destroy "vrf-r2"
 }
 
+multipath_eval()
+{
+       local weight_rp12=$1
+       local weight_rp13=$2
+       local packets_rp12=$3
+       local packets_rp13=$4
+       local weights_ratio packets_ratio diff
+
+       RET=0
+
+       if [[ "$weight_rp12" -gt "$weight_rp13" ]]; then
+               weights_ratio=$(echo "scale=2; $weight_rp12 / $weight_rp13" \
+                      | bc -l)
+               packets_ratio=$(echo "scale=2; $packets_rp12 / $packets_rp13" \
+                      | bc -l)
+       else
+               weights_ratio=$(echo "scale=2; $weight_rp13 / $weight_rp12" | \
+                      bc -l)
+               packets_ratio=$(echo "scale=2; $packets_rp13 / $packets_rp12" | \
+                      bc -l)
+       fi
+
+       diff=$(echo $weights_ratio - $packets_ratio | bc -l)
+       diff=${diff#-}
+
+       test "$(echo "$diff / $weights_ratio > 0.1" | bc -l)" -eq 0
+       check_err $? "Too large discrepancy between expected and measured ratios"
+       log_test "Multipath"
+       log_info "Expected ratio $weights_ratio Measured ratio $packets_ratio"
+}
+
+multipath4_test()
+{
+       local weight_rp12=$1
+       local weight_rp13=$2
+       local t0_rp12 t0_rp13 t1_rp12 t1_rp13
+       local packets_rp12 packets_rp13
+       local hash_policy
+
+       # Transmit multiple flows from h1 to h2 and make sure they are
+       # distributed between both multipath links (rp12 and rp13)
+       # according to the configured weights.
+       hash_policy=$(sysctl -n net.ipv4.fib_multipath_hash_policy)
+       sysctl -q -w net.ipv4.fib_multipath_hash_policy=1
+       ip route replace 198.51.100.0/24 vrf vrf-r1 \
+               nexthop via 169.254.2.22 dev $rp12 weight $weight_rp12 \
+               nexthop via 169.254.3.23 dev $rp13 weight $weight_rp13
+
+       t0_rp12=$(link_stats_tx_packets_get $rp12)
+       t0_rp13=$(link_stats_tx_packets_get $rp13)
+
+       ip vrf exec vrf-h1 $MZ -q -p 64 -A 192.0.2.2 -B 198.51.100.2 \
+              -d 1msec -t udp "sp=1024,dp=0-32768"
+
+       t1_rp12=$(link_stats_tx_packets_get $rp12)
+       t1_rp13=$(link_stats_tx_packets_get $rp13)
+
+       let "packets_rp12 = $t1_rp12 - $t0_rp12"
+       let "packets_rp13 = $t1_rp13 - $t0_rp13"
+       multipath_eval $weight_rp12 $weight_rp13 $packets_rp12 $packets_rp13
+
+       # Restore settings.
+       ip route replace 198.51.100.0/24 vrf vrf-r1 \
+               nexthop via 169.254.2.22 dev $rp12 \
+               nexthop via 169.254.3.23 dev $rp13
+       sysctl -q -w net.ipv4.fib_multipath_hash_policy=$hash_policy
+}
+
+multipath_test()
+{
+       log_info "Running IPv4 multipath tests"
+       multipath4_test 1 1
+       multipath4_test 2 1
+       multipath4_test 11 45
+}
+
 setup_prepare()
 {
        h1=${NETIFS[p1]}
@@ -205,5 +281,6 @@ setup_wait
 
 ping_test $h1 198.51.100.2
 ping6_test $h1 2001:db8:2::2
+multipath_test
 
 exit $EXIT_STATUS