selftests: router_mpath: Sleep after MZ

In the context of an offloaded datapath, it may take a while for the ip
link stats to be updated. This causes the test to fail when MZ_DELAY is too
low. Sleep after the packets are sent for the link stats to get up to date.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/8b1971d948273afd7de2da3d6a2ba35200540e55.1723036486.git.petrm@nvidia.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

tools/testing/selftests/net/forwarding/router_mpath_nh.sh

@@ -243,6 +243,7 @@ multipath4_test()
 
 	ip vrf exec vrf-h1 $MZ $h1 -q -p 64 -A 192.0.2.2 -B 198.51.100.2 \
 		-d $MZ_DELAY -t udp "sp=1024,dp=0-32768"
+	sleep 1
 
 	t1_rp12=$(link_stats_tx_packets_get $rp12)
 	t1_rp13=$(link_stats_tx_packets_get $rp13)
@@ -276,6 +277,7 @@ multipath6_test()
 
 	$MZ $h1 -6 -q -p 64 -A 2001:db8:1::2 -B 2001:db8:2::2 \
 		-d $MZ_DELAY -t udp "sp=1024,dp=0-32768"
+	sleep 1
 
 	t1_rp12=$(link_stats_tx_packets_get $rp12)
 	t1_rp13=$(link_stats_tx_packets_get $rp13)

tools/testing/selftests/net/forwarding/router_mpath_nh_res.sh

@@ -244,6 +244,7 @@ multipath4_test()
 
 	ip vrf exec vrf-h1 $MZ $h1 -q -p 64 -A 192.0.2.2 -B 198.51.100.2 \
 		-d $MZ_DELAY -t udp "sp=1024,dp=0-32768"
+	sleep 1
 
 	t1_rp12=$(link_stats_tx_packets_get $rp12)
 	t1_rp13=$(link_stats_tx_packets_get $rp13)
@@ -274,6 +275,7 @@ multipath6_l4_test()
 
 	$MZ $h1 -6 -q -p 64 -A 2001:db8:1::2 -B 2001:db8:2::2 \
 		-d $MZ_DELAY -t udp "sp=1024,dp=0-32768"
+	sleep 1
 
 	t1_rp12=$(link_stats_tx_packets_get $rp12)
 	t1_rp13=$(link_stats_tx_packets_get $rp13)

tools/testing/selftests/net/forwarding/router_multipath.sh

@@ -180,6 +180,7 @@ multipath4_test()
 
        ip vrf exec vrf-h1 $MZ $h1 -q -p 64 -A 192.0.2.2 -B 198.51.100.2 \
 	       -d $MZ_DELAY -t udp "sp=1024,dp=0-32768"
+       sleep 1
 
        t1_rp12=$(link_stats_tx_packets_get $rp12)
        t1_rp13=$(link_stats_tx_packets_get $rp13)
@@ -217,6 +218,7 @@ multipath6_test()
 
        $MZ $h1 -6 -q -p 64 -A 2001:db8:1::2 -B 2001:db8:2::2 \
 	       -d $MZ_DELAY -t udp "sp=1024,dp=0-32768"
+       sleep 1
 
        t1_rp12=$(link_stats_tx_packets_get $rp12)
        t1_rp13=$(link_stats_tx_packets_get $rp13)