Re: [PATCH net-next v2] selftests: openvswitch: retry instead of sleep

On Wed, Jul 10, 2024 at 11:04:59AM GMT, Adrian Moreno wrote:

There are a couple of places where the test script "sleep"s to wait for some external condition to be met.

This is error prone, specially in slow systems (identified in CI by "KSFT_MACHINE_SLOW=yes").

To fix this, add a "ovs_wait" function that tries to execute a command a few times until it succeeds. The timeout used is set to 5s for "normal" systems and doubled if a slow CI machine is detected.

This should make the following work:

$ vng --build \ --config tools/testing/selftests/net/config \ --config kernel/configs/debug.config

$ vng --run . --user root -- "make -C tools/testing/selftests/ \ KSFT_MACHINE_SLOW=yes TARGETS=net/openvswitch run_tests"

Signed-off-by: Adrian Moreno amorenoz@redhat.com

.../selftests/net/openvswitch/openvswitch.sh | 45 +++++++++++++++---- .../selftests/net/openvswitch/ovs-dpctl.py | 1 + 2 files changed, 38 insertions(+), 8 deletions(-)

diff --git a/tools/testing/selftests/net/openvswitch/openvswitch.sh b/tools/testing/selftests/net/openvswitch/openvswitch.sh index bc71dbc18b21..cc0bfae2bafa 100755 --- a/tools/testing/selftests/net/openvswitch/openvswitch.sh +++ b/tools/testing/selftests/net/openvswitch/openvswitch.sh @@ -11,6 +11,11 @@ ksft_skip=4 PAUSE_ON_FAIL=no VERBOSE=0 TRACING=0 +WAIT_TIMEOUT=5

+if test "X$KSFT_MACHINE_SLOW" == "Xyes"; then

• WAIT_TIMEOUT=10

+fi

tests=" arp_ping eth-arp: Basic arp ping between two NS @@ -29,6 +34,30 @@ info() { [ $VERBOSE = 0 ] || echo $* }

+ovs_wait() {

• info "waiting $WAIT_TIMEOUT s for: $@"
• if "$@" ; then

• info "wait succeeded immediately"
  

• return 0
  

• fi
• # A quick re-check helps speed up small races in fast systems.
• # However, fractional sleeps might not necessarily work.
• local start=0
• sleep 0.1 || { sleep 1; start=1; }
• for (( i=start; i<WAIT_TIMEOUT; i++ )); do

• if "$@" ; then
  

• 	info "wait succeeded after $i seconds"
  

• 	return 0
  

• fi
  

• sleep 1
  

• done
• info "wait failed after $i seconds"
• return 1

+}

ovs_base=`pwd` sbxs= sbx_add () { @@ -278,20 +307,19 @@ test_psample() {

# Record psample data. ovs_spawn_daemon "test_psample" python3 $ovs_base/ovs-dpctl.py psample-events

• ovs_wait grep -q "listening for psample events" ${ovs_dir}/stdout

  # Send a single ping.

• sleep 1 ovs_sbx "test_psample" ip netns exec client ping -I c1 172.31.110.20 -c 1 || return 1

• sleep 1

  # We should have received one userspace action upcall and 2 psample packets.

• grep -E "userspace action command" $ovs_dir/s0.out >/dev/null 2>&1 || return 1

• ovs_wait grep -q "userspace action command" $ovs_dir/s0.out || return 1

  # client -> server samples should only contain the first 14 bytes of the packet.

• grep -E "rate:4294967295,group:1,cookie:c0ffee data:[0-9a-f]{28}$" \

• 	 $ovs_dir/stdout >/dev/null 2>&1 || return 1
  

• grep -E "rate:4294967295,group:2,cookie:eeff0c" \

• 	 $ovs_dir/stdout >/dev/null 2>&1 || return 1
  

• ovs_wait grep -qE "rate:4294967295,group:1,cookie:c0ffee data:[0-9a-f]{28}$" \

• $ovs_dir/stdout || return 1
  

• ovs_wait grep -q "rate:4294967295,group:2,cookie:eeff0c" $ovs_dir/stdout || return 1

  return 0

} @@ -711,7 +739,8 @@ test_upcall_interfaces() { ovs_add_netns_and_veths "test_upcall_interfaces" ui0 upc left0 l0 \ 172.31.110.1/24 -u || return 1

• sleep 1

• ovs_wait grep -q "listening on upcall packet handler" ${ovs_dir}/left0.out
• info "sending arping" ip netns exec upc arping -I l0 172.31.110.20 -c 1 \ >$ovs_dir/arping.stdout 2>$ovs_dir/arping.stderr

diff --git a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py index 1e15b0818074..8a0396bfaf99 100644 --- a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py +++ b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py @@ -2520,6 +2520,7 @@ class PsampleEvent(EventSocket): marshal_class = psample_msg

 def read_samples(self):

•    print("listening for psample events", flush=True)
     while True:
         try:
             for msg in self.get():
  

-- 2.45.2

This patch is supposed to fix openvswitch selftests on "-dbg" machines. However, as Simon points out, all recent rounds are failing [1]. I don't see this patch being included in the batches and I was wondering why.

Also I see a (presumably unrelated) build error netdev/build_32bit. Is there anything I can do?

[1] https://netdev.bots.linux.dev/contest.html?executor=vmksft-net-dbg&test=...

Thanks. Adrián