On Mon, Dec 13, 2021 at 03:26:56PM +0100, Horatiu Vultur wrote: > > They are independent of each other. You deduce the interface on which > > the notifier was emitted using switchdev_notifier_info_to_dev() and act > > upon it, if lan966x_netdevice_check() is true. The notifier handling > > code itself is stateless, all the state is per port / per switch. > > If you register one notifier handler per switch, lan966x_netdevice_check() > > would return true for each notifier handler instance, and you would > > handle each event twice, would you not? > > That is correct, I will get the event twice which is a problem in the > lan966x. The function lan966x_netdevice_check should be per instance, in > this way each instance can filter the events. > The reason why I am putting the notifier_block inside lan966x is to be > able to get to the instance of lan966x even if I get a event that is not > for lan966x port. That isn't a problem, every netdevice notifier still sees all events. DSA intercepts a lot of events which aren't directly emitted for its own interfaces. You don't gain much by having one more, if anything. > > notifier handlers should be registered as singletons, like other drivers > > do. > > It looks like not all the other driver register them as singletone. For > example: prestera, mlx5, sparx5. (I just have done a git grep for > register_switchdev_notifier, I have not looked in details at the > implementation). Not all driver writers may have realized that it is an issue that needs to be thought of.
