On 2021/6/3 0:58, Jakub Kicinski wrote:

On Wed, 2 Jun 2021 15:17:13 +0300 dlinkin@nvidia.com wrote:

quoted

From: Dmytro Linkin <redacted>

Resending without RFC.

Currently kernel provides a way to change tx rate of single VF in
switchdev mode via tc-police action. When lots of VFs are configured
management of theirs rates becomes non-trivial task and some grouping
mechanism is required. Implementing such grouping in tc-police will bring
flow related limitations and unwanted complications, like:
- tc-police is a policer and there is a user request for a traffic
  shaper, so shared tc-police action is not suitable;
- flows requires net device to be placed on, means "groups" wouldn't
  have net device instance itself. Taking into the account previous
  point was reviewed a sollution, when representor have a policer and
  the driver use a shaper if qdisc contains group of VFs - such approach
  ugly, compilated and misleading;
- TC is ingress only, while configuring "other" side of the wire looks
  more like a "real" picture where shaping is outside of the steering
  world, similar to "ip link" command;

According to that devlink is the most appropriate place.

I don't think you researched TC well enough. But whatever, I'm tired 
of being the only one who pushes back given I neither work on or use
any of these features.

tc action offload feature used in [1] seems to solve the
police action lifecycle problem?

And it seem to allow different flow to use the same action,
I am not sure if different function can use the same action,
it seems jianbo has mentioned about the same usecase?

1. https://lore.kernel.org/netdev/CALnP8ZaZQAbvm1girLUSLcFZTKV5MvBMEtN67OiA55OAvsO_1Q@mail.gmail.com/T/ (local)