Re: [PATCH net-next v2 00/10] net: dsa: add generic debugfs interface

Andrew Lunn
2017-08-29T12:50:04Z

On Tue, Aug 29, 2017 at 08:25:23AM +0200, Jiri Pirko wrote:
> Mon, Aug 28, 2017 at 10:08:34PM CEST, andrew@lunn.ch wrote:
> >> I see this overlaps a lot with DPIPE. Why won't you use that to expose
> >> your hw state?
> >
> >We took a look at dpipe and i talked to you about using it for this
> >sort of thing at netconf/netdev. But dpipe has issues displaying the
> >sort of information we have. I never figured out how to do two
> >dimensional tables. The output of the dpipe command is pretty
> >unreadable. A lot of the information being dumped here is not about
> >the data pipe, etc.
>
> So improve it. No problem. Also, we extend it to support what you neede.

Will i did try to do this back in March. And i failed.

Lets start with stats. Vivien gives an example on the cover letter:

# pr -mt switch0/port{5,6}/stats
in_good_octets : 0 in_good_octets : 13824
in_bad_octets : 0 in_bad_octets : 0
in_unicast : 0 in_unicast : 0
in_broadcasts : 0 in_broadcasts : 216
in_multicasts : 0 in_multicasts : 0
in_pause : 0 in_pause : 0
in_undersize : 0 in_undersize : 0

This is what i tried to implement using dpipe. It is a simple two
dimensional table. First column is a string, second a u64. In debugfs
we have such a table per port. That fits with the hierarchy that each
port is a directory in debugfs. But it could also be implemented as
one table with N+1 columns, for N switch ports.

How about you, or one of your team, implement that. It should be able
to use the dsa_loop driver, which is a simple dummy switch. But it
does have statistics counters for all ports. Florian or I can help you
get it running if needed.

This branch contains some of the basic plumbing code from my previous
attempt:

https://github.com/lunn/linux.git v4.11-rc4-net-next-dpipe

Andrew