Re: [PATCH] selftests: txtimestamp: tear down setup() 'tc' and 'ip' env on EXIT

[Willem de Bruijn]

On Tue, Jul 21, 2020 at 10:52 AM Paolo Pisati
 wrote:
>
> Add a cleanup() path upon exit, making it possible to run the test twice in a
> row:
>
> $ sudo bash -x ./txtimestamp.sh
> + set -e
> ++ ip netns identify
> + [[ '' == \r\o\o\t ]]
> + main
> + [[ 0 -eq 0 ]]
> + run_test_all
> + setup
> + tc qdisc add dev lo root netem delay 1ms
> Error: Exclusivity flag on, cannot modify.
>
> Signed-off-by: Paolo Pisati 

The test should already clean up after itself, by being run inside a
network namespace. That is a more robust method to ensure that all
state is reset.

The issue here is that the else branch is taken in

  if [[ "$(ip netns identify)" == "root" ]]; then
  ./in_netns.sh $0 $@
  else
  main $@
  fi

because the ip netns identify usually returns an empty string, not
"root". If we fix that, no need to add additional cleanup.

[PATCH] selftests: txtimestamp: tear down setup() 'tc' and 'ip' env on EXIT

[Paolo Pisati]

Add a cleanup() path upon exit, making it possible to run the test twice in a
row:

$ sudo bash -x ./txtimestamp.sh
+ set -e
++ ip netns identify
+ [[ '' == \r\o\o\t ]]
+ main
+ [[ 0 -eq 0 ]]
+ run_test_all
+ setup
+ tc qdisc add dev lo root netem delay 1ms
Error: Exclusivity flag on, cannot modify.

Signed-off-by: Paolo Pisati 
---
 tools/testing/selftests/net/txtimestamp.sh | 10 ++
 1 file changed, 10 insertions(+)

diff --git a/tools/testing/selftests/net/txtimestamp.sh 
b/tools/testing/selftests/net/txtimestamp.sh
index eea6f5193693..77f29cabff87 100755
--- a/tools/testing/selftests/net/txtimestamp.sh
+++ b/tools/testing/selftests/net/txtimestamp.sh
@@ -23,6 +23,14 @@ setup() {
action mirred egress redirect dev ifb_netem0
 }
 
+cleanup() {
+   tc filter del dev lo parent :
+   tc qdisc del dev lo handle : ingress
+   tc qdisc del dev ifb_netem0 root
+   ip link del ifb_netem0
+   tc qdisc del dev lo root
+}
+
 run_test_v4v6() {
# SND will be delayed 1000us
# ACK will be delayed 6000us: 1 + 2 ms round-trip
@@ -75,6 +83,8 @@ main() {
fi
 }
 
+trap cleanup EXIT
+
 if [[ "$(ip netns identify)" == "root" ]]; then
./in_netns.sh $0 $@
 else
-- 
2.27.0