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

On 3/23/18 9:01 AM, Jiri Pirko wrote:

Fri, Mar 23, 2018 at 03:31:02PM CET, dsa@cumulusnetworks.com wrote:

quoted

On 3/23/18 12:50 AM, Jiri Pirko wrote:

quoted

quoted

+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.

quoted

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.

you need to look at how netdevsim creates a device per netdevice.