On Mon, Aug 17, 2020 at 04:29:52PM +0200, Andrew Lunn wrote:
> > +static int mlxsw_sp1_nve_vxlan_metrics_init(struct mlxsw_sp *mlxsw_sp)
> > +{
> > + struct mlxsw_sp_nve_metrics *metrics = &mlxsw_sp->nve->metrics;
> > + struct devlink *devlink = priv_to_devlink(mlxsw_sp->core);
> > + int err;
> > +
> > + err = mlxsw_sp1_nve_vxlan_counters_clear(mlxsw_sp);
> > + if (err)
> > + return err;
> > +
> > + metrics->counter_encap =
> > + devlink_metric_counter_create(devlink, "nve_vxlan_encap",
> > + &mlxsw_sp1_nve_vxlan_encap_ops,
> > + mlxsw_sp);
> > + if (IS_ERR(metrics->counter_encap))
> > + return PTR_ERR(metrics->counter_encap);
> > +
> > + metrics->counter_decap =
> > + devlink_metric_counter_create(devlink, "nve_vxlan_decap",
> > + &mlxsw_sp1_nve_vxlan_decap_ops,
> > + mlxsw_sp);
> > + if (IS_ERR(metrics->counter_decap)) {
> > + err = PTR_ERR(metrics->counter_decap);
> > + goto err_counter_decap;
> > + }
> > +
> > + metrics->counter_decap_errors =
> > + devlink_metric_counter_create(devlink, "nve_vxlan_decap_errors",
> > +
> > &mlxsw_sp1_nve_vxlan_decap_errors_ops,
> > + mlxsw_sp);
> > + if (IS_ERR(metrics->counter_decap_errors)) {
> > + err = PTR_ERR(metrics->counter_decap_errors);
> > + goto err_counter_decap_errors;
> > + }
> > +
> > + metrics->counter_decap_discards =
> > + devlink_metric_counter_create(devlink,
> > "nve_vxlan_decap_discards",
> > +
> > &mlxsw_sp1_nve_vxlan_decap_discards_ops,
> > + mlxsw_sp);
> > + if (IS_ERR(metrics->counter_decap_discards)) {
> > + err = PTR_ERR(metrics->counter_decap_discards);
> > + goto err_counter_decap_discards;
> > + }
> > +
> > + return 0;
>
> Looking at this, i wonder about the scalability of this API. With just
> 4 counters it looks pretty ugly. What about 50 counters?
>
> Maybe move the name into the ops structure. Then add a call
> devlink_metric_counters_create() where you can pass an array and array
> size of op structures? There are plenty of other examples in the
> kernel, e.g. sysfs groups, hwmon, etc. where you register a large
> bunch of things with the core with a single call.
Yes, good suggestion. Will add the ability to register multiple metrics
at once.
>
> > +static void mlxsw_sp1_nve_vxlan_metrics_fini(struct mlxsw_sp *mlxsw_sp)
> > +{
> > + struct mlxsw_sp_nve_metrics *metrics = &mlxsw_sp->nve->metrics;
> > + struct devlink *devlink = priv_to_devlink(mlxsw_sp->core);
> > +
> > + devlink_metric_destroy(devlink, metrics->counter_decap_discards);
> > + devlink_metric_destroy(devlink, metrics->counter_decap_errors);
> > + devlink_metric_destroy(devlink, metrics->counter_decap);
> > + devlink_metric_destroy(devlink, metrics->counter_encap);
> > +}
>
> I guess the most frequent use case is to remove all counters,
> e.g. driver unload, or when probe fails. So maybe provide a
> devlink_metric_destroy_all(devlink) ?
If we are going to add something like devlink_metric_counters_create(),
then we can also add devlink_metrics_destroy() which will remove all
provided metrics in one call. I prefer it over _all() because then it's
symmetric with _create() operation.
Thanks!
