Subject: Re: [PATCH net] selftests: bonding: Add more missing config options

From: Hangbin Liu <[email-masked]>
Date: Wed, 17 Jan 2024 11:15:49 +0800

On Tue, Jan 16, 2024 at 02:47:46PM -0500, Benjamin Poirier wrote:
> On 2024-01-16 11:29 -0800, Jakub Kicinski wrote:
> > On Tue, 16 Jan 2024 14:21:51 -0500 Benjamin Poirier wrote:
> > > real    13m35.065s
> > > user    0m1.657s
> > > sys     0m27.918s
> > > 
> > > The test is not cpu bound; as Jay pointed out, it spends most of its
> > > time sleeping.
> > 
> > Ugh, so it does multiple iterations of 118 sec?
> 
> There are other test functions in the script which include a lot of
> sleeping.

The arp_validate_test need to check the mii_status, which sleep too much time.
Maybe we can use busywait to save more time.

> 
> > Could you send a patch to bump the timeout to 900 or 1200 in this case?
> 
> Sure but I'd like to give a chance for Hangbin to reply first. Would the
> test be just as good if it was shortened by removing some cases or
> reducing the time intervals? Or is increasing the timeout the best
> approach?

The purpose of grat_arp is testing commit 9949e2efb54e ("bonding: fix
send_peer_notif overflow"). As the send_peer_notif was defined to u8,
to overflow it, we need to

send_peer_notif = num_peer_notif * peer_notif_delay = num_grat_arp * peer_notify_delay / miimon > 255
  (kernel)           (kernel parameter)                   (user parameter)

e.g. 30 (num_grat_arp) * 1000 (peer_notify_delay) / 100 (miimon) > 255.

Which need 30s to complete sending garp messages. To save the testing time,
the only way is reduce the miimon number. Something like
30 (num_grat_arp) * 500 (peer_notify_delay) / 50 (miimon) > 255.

To save more time, we can remove the 50 num_grat_arp testing. The patch would
like

diff --git a/tools/testing/selftests/drivers/net/bonding/bond_options.sh b/tools/testing/selftests/drivers/net/bonding/bond_options.sh
index c54d1697f439..20c4d862c436 100755
--- a/tools/testing/selftests/drivers/net/bonding/bond_options.sh
+++ b/tools/testing/selftests/drivers/net/bonding/bond_options.sh
@@ -277,7 +277,7 @@ garp_test()
        ip -n ${s_ns} link set ${active_slave} down

        exp_num=$(echo "${param}" | cut -f6 -d ' ')
-       sleep $((exp_num + 2))
+       sleep $((exp_num / 2 + 2))

        active_slave=$(cmd_jq "ip -n ${s_ns} -d -j link show bond0" ".[].linkinfo.info_data.active_slave")

@@ -296,8 +296,8 @@ garp_test()
 num_grat_arp()
 {
        local val
-       for val in 10 20 30 50; do
-               garp_test "mode active-backup miimon 100 num_grat_arp $val peer_notify_delay 1000"
+       for val in 10 20 30; do
+               garp_test "mode active-backup miimon 50 num_grat_arp $val peer_notify_delay 500"
                log_test "num_grat_arp" "active-backup miimon num_grat_arp $val"
        done
 }

With this we can save 100s.

Thanks
Hangbin