Subject: Re: [PATCH RFC net-next 7/7] netdevsim: Add simple FIB resource controller via devlink

From: Jiri Pirko <[email-masked]>
Date: Fri, 23 Mar 2018 16:01:49 +0100

Fri, Mar 23, 2018 at 03:31:02PM CET, [email-masked] wrote:
>On 3/23/18 12:50 AM, Jiri Pirko wrote:
>>> +void nsim_devlink_setup(struct netdevsim *ns)
>>> +{
>>> +	struct net *net = dev_net(ns->netdev);
>>> +	bool *reg_devlink = net_generic(net, nsim_devlink_id);
>>> +	struct devlink *devlink;
>>> +	int err = -ENOMEM;
>>> +
>>> +	/* only one device per namespace controls devlink */
>>> +	if (!*reg_devlink) {
>>> +		ns->devlink = NULL;
>>> +		return;
>>> +	}
>>> +
>>> +	devlink = devlink_alloc(&nsim_devlink_ops, 0);
>>> +	if (!devlink)
>>> +		return;
>>> +
>>> +	devlink_net_set(devlink, net);
>>> +	err = devlink_register(devlink, &ns->dev);
>> 
>> This reg_devlink construct looks odd. Why don't you leave the devlink
>> instance in init_ns?
>
>It is a per-network namespace resource controller. Since struct devlink

Wait a second. What do you mean by "per-network namespace"? Devlink
instance is always associated with one physical device. Like an ASIC.

>has a net entry, the simplest design is to put it into the namespace of
>the controller. Without it, controlling resource sizes in namespace
>'foobar' has to be done from init_net, which is just wrong.