selftests/bpf/test_xdp_meta: use temp netns for testing

Use temp netns instead of hard code name for testing in case the
netns already exists.
Signed-off-by: NHangbin Liu <liuhangbin@gmail.com>
Link: https://lore.kernel.org/r/20220125081717.1260849-7-liuhangbin@gmail.comSigned-off-by: NAlexei Starovoitov <ast@kernel.org>

tools/testing/selftests/bpf/test_xdp_meta.sh

@@ -2,6 +2,8 @@
 
 # Kselftest framework requirement - SKIP code is 4.
 readonly KSFT_SKIP=4
+readonly NS1="ns1-$(mktemp -u XXXXXX)"
+readonly NS2="ns2-$(mktemp -u XXXXXX)"
 
 cleanup()
 {
@@ -13,8 +15,8 @@ cleanup()
 
 	set +e
 	ip link del veth1 2> /dev/null
-	ip netns del ns1 2> /dev/null
-	ip netns del ns2 2> /dev/null
+	ip netns del ${NS1} 2> /dev/null
+	ip netns del ${NS2} 2> /dev/null
 }
 
 ip link set dev lo xdp off 2>/dev/null > /dev/null
@@ -24,32 +26,32 @@ if [ $? -ne 0 ];then
 fi
 set -e
 
-ip netns add ns1
-ip netns add ns2
+ip netns add ${NS1}
+ip netns add ${NS2}
 
 trap cleanup 0 2 3 6 9
 
 ip link add veth1 type veth peer name veth2
 
-ip link set veth1 netns ns1
-ip link set veth2 netns ns2
+ip link set veth1 netns ${NS1}
+ip link set veth2 netns ${NS2}
 
-ip netns exec ns1 ip addr add 10.1.1.11/24 dev veth1
-ip netns exec ns2 ip addr add 10.1.1.22/24 dev veth2
+ip netns exec ${NS1} ip addr add 10.1.1.11/24 dev veth1
+ip netns exec ${NS2} ip addr add 10.1.1.22/24 dev veth2
 
-ip netns exec ns1 tc qdisc add dev veth1 clsact
-ip netns exec ns2 tc qdisc add dev veth2 clsact
+ip netns exec ${NS1} tc qdisc add dev veth1 clsact
+ip netns exec ${NS2} tc qdisc add dev veth2 clsact
 
-ip netns exec ns1 tc filter add dev veth1 ingress bpf da obj test_xdp_meta.o sec t
-ip netns exec ns2 tc filter add dev veth2 ingress bpf da obj test_xdp_meta.o sec t
+ip netns exec ${NS1} tc filter add dev veth1 ingress bpf da obj test_xdp_meta.o sec t
+ip netns exec ${NS2} tc filter add dev veth2 ingress bpf da obj test_xdp_meta.o sec t
 
-ip netns exec ns1 ip link set dev veth1 xdp obj test_xdp_meta.o sec x
-ip netns exec ns2 ip link set dev veth2 xdp obj test_xdp_meta.o sec x
+ip netns exec ${NS1} ip link set dev veth1 xdp obj test_xdp_meta.o sec x
+ip netns exec ${NS2} ip link set dev veth2 xdp obj test_xdp_meta.o sec x
 
-ip netns exec ns1 ip link set dev veth1 up
-ip netns exec ns2 ip link set dev veth2 up
+ip netns exec ${NS1} ip link set dev veth1 up
+ip netns exec ${NS2} ip link set dev veth2 up
 
-ip netns exec ns1 ping -c 1 10.1.1.22
-ip netns exec ns2 ping -c 1 10.1.1.11
+ip netns exec ${NS1} ping -c 1 10.1.1.22
+ip netns exec ${NS2} ping -c 1 10.1.1.11
 
 exit 0