[ovs-discuss] question regarding utilities/nlmon.c tool

[Mohammad Heib]

Hi Gregory,
Thank you for the quick response :),
i have already implemented a basic TC Netlink monitor that is based on
nlmon code and it partially works
with some missing pieces, and waiting to hear from you if that ok to rely
on nlmon code.

Thanks,
Mohammad

On Wed, Nov 10, 2021 at 12:15 AM Gregory Rose <gvrose8192 at gmail.com> wrote:

>
>
> On 11/9/2021 8:05 AM, Mohammad Heib wrote:
> > hi folks,
> > i was looking for a way to monitor OVS TC Netlink messages that OVS sends
> > to TC when HW offloads are on (mostly for testing HWOL over non-supported
> > HW offload system ).
> >
> > as i understood, those Netlink's messages will be sent back from the
> kernel
> > to TC Netlink multicast group after the TC subsystem is finished
> processing
> > those requests, and the userspace process can capture them by listing to
> > the appropriate group.
> >
> > unfortunately, i didn't find any tool that give me the ability to capture
> > and parse (print) those TC Netlink messages.
> > so I started to implement my own tool but after a few more
> investigations I
> > found that nlmon already implement similar behavior for capturing Netlink
> > Link changes messages.
> >
> > so I was wondering if:
> > 1. I can convert nlmon code to be more generic and easier to add and
> > monitor new Netlink groups?
> > 2. can I add Netlink TC messages monitoring implementation to nlmon?
> >
> > if the answer to 2 was yes :) ,
> > I have some dependencies that need to be included from linux/pkt_cls.h
> > which is a kernel header file and not sure if I can include it in nlmon ?
> > is that possible to include this file in nlmon.c? or is it ok to copy
> those
> > dependencies to a local file (maybe nlmon.h) especially that most of
> those
> > dependencies are enums and defines (e.g TCA_*/TCA_FLOWER_*)?.
>
> Hi Mohammed,
>
> I was looking into TC flower Netlink monitoring myself but haven't
> had a real chance to dig deeper into it.  However, the nlmon tool you
> mentioned looks very interesting.  I'll check it out and if I see an
> answer to question #2 I'll get back to you.
>
> Thanks,
>
> - Greg
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.openvswitch.org/pipermail/ovs-discuss/attachments/20211111/2ec903bb/attachment.html>