On Mon, 10 Jul 2023 18:51:19 +0200 Ilya Maximets wrote: > Makes sense. I wasn't sure that's a good solution from a kernel perspective > either. It's better than defining all these reasons, IMO, but it's not good > enough to be considered acceptable, I agree. > > How about we define just 2 reasons, e.g. OVS_DROP_REASON_EXPLICIT_ACTION and > OVS_DROP_REASON_EXPLICIT_ACTION_WITH_ERROR (exact names can be different) ? > One for an explicit drop action with a zero argument and one for an explicit > drop with non-zero argument. > > The exact reason for the error can be retrieved by other means, i.e by looking > at the datapath flow dump or OVS logs/traces. > > This way we can give a user who is catching packet drop traces a signal that > there was something wrong with an OVS flow and they can look up exact details > from the userspace / flow dump. > > The point being, most of the flows will have a zero as a drop action argument, > i.e. a regular explicit packet drop. It will be hard to figure out which flow > exactly we're hitting without looking at the full flow dump. And if the value > is non-zero, then it should be immediately obvious which flow is to blame from > the dump, as we should not have a lot of such flows. > > This would still allow us to avoid a maintenance burden of defining every > case, > which are fairly meaningless for the kernel itself, while having 99% of the > information we may need. > > Jakub, do you think this will be acceptable?
As far as I understand what you're proposing, yes :) > Eric, Adrian, Aaron, do you see any problems with such implementation? > > P.S. There is a plan to add more drop reasons for other places in openvswitch > module to catch more regular types of drops like memory issues or upcall > failures. So, the drop reason subsystem can be extended later. > The explicit drop action is a bit of an odd case here. If you have more than ~4 OvS specific reasons, I wonder if it still makes sense to create a reason group/subsystem for OvS (a'la WiFi)? _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
