Tue, Apr 23, 2019 at 07:05:28PM CEST, jakub.kicin...@netronome.com wrote:
>On Tue, 23 Apr 2019 09:20:14 +0200, Jiri Pirko wrote:
>> Mon, Apr 22, 2019 at 09:31:33PM CEST, jakub.kicin...@netronome.com wrote:
>> >On Sat, 20 Apr 2019 12:29:21 +0200, Jiri Pirko wrote:
>> >> diff --git a/tools/testing/selftests/bpf/test_offload.py
>> >> b/tools/testing/selftests/bpf/test_offload.py
>> >> index 5f2e4f9e70e4..a0566dcf064a 100755
>> >> --- a/tools/testing/selftests/bpf/test_offload.py
>> >> +++ b/tools/testing/selftests/bpf/test_offload.py
>> >> @@ -1,6 +1,7 @@
>> >> #!/usr/bin/python3
>> >>
>> >> # Copyright (C) 2017 Netronome Systems, Inc.
>> >> +# Copyright (c) 2019 Mellanox Technologies. All rights reserved
>> >
>> >What's your guiding principle with adding those copyright lines
>> >everywhere?
>>
>> Semi-random :) I can remove it if you want.
>
>Technically I have no opinion, personally I find it petty and
>unnecessary in the git era.. Probably not worth your time now
>to go and remove :)
>
>> >> +class NetdevSim:
>> >> + """
>> >> + Class for netdevsim netdevice and its attributes.
>> >> + """
>> >> +
>> >> + def __init__(self, nsimdev, port_index):
>> >> + self.nsimdev = nsimdev
>> >> + self.port_index = port_index
>> >> + self.ns = ""
>> >> + self.dfs_dir = "%s/ports/%u/" % (nsimdev.dfs_dir, port_index)
>> >> + self.dfs_refresh()
>> >> +
>> >> + ifname = "eni%unp%u" % (nsimdev.addr, port_index + 1)
>> >> + timeout = 0.5
>> >> + timeout_start = time.time()
>> >> +
>> >> + while True:
>> >> + try:
>> >> + _, [self.dev] = ip("link show dev %s" % ifname)
>> >> + except Exception as e:
>> >> + if time.time() < timeout_start + timeout:
>> >> + continue
>> >> + raise e
>> >> + break
>> >
>> >udevadm settle? The reliance on latest systemd is a real bad idea,
>>
>> Not sure that "udevadm settle" would help here. The diver bus probe handle
>> may be executed from a workqueue, so here, there might be the udev event
>> queue empty yet still the netdev is not present.
>
>Mm.. true. I must say I had a ton of issues with this in Netronome
>test systems, those "wait for renames" loop always broke no matter
>what.. OS upgrade, adding debug stuff into the kernel.. I get
>flashbacks. I've seen udev easily take 20s to rename on a heavy kernel.
>Since we replaced the loops with udevadm settle - it's been a bliss.
>YMMV but in my experience regardless of workqueues and all udev is way
>more reliable.
Sure, But I don't see how udevadm settle would help here. Hmm but
perhaps I can poll sysfs until the device appears there and then I can
udevadm settle.
>
>> >could you fall back to netdevsimX names if eni$SOME$CUFT is not found?
>>
>> That would not help. If you have udev which does not support this, you
>> are going to endup with "eth0, eth1, .."
>
>That is not great :( The kbuild bot runs BPF offload tests, they run
>with some CentOS user space. If we don't want to name the device in
>the kernel, perhaps it'd be possible to scan sysfs? The ifc names
>should be under $device/net/, right?
Yeah, hmm. I'll think about it and fix. Thanks!
