On Tue, Aug 10, 2021 at 06:08:51PM +0530, Prabhakar Kushwaha wrote:
> Hi Leon,
<...>
> > struct devlink *devlink_alloc_ns(const struct devlink_ops *ops,
> > - size_t priv_size, struct net *net)
> > + size_t priv_size, struct net *net,
> > + struct device *dev)
> > {
> > struct devlink *devlink;
> >
> > - if (WARN_ON(!ops))
> > - return NULL;
> > -
> > + WARN_ON(!ops || !dev);
> > if (!devlink_reload_actions_valid(ops))
> > return NULL;
> >
> > devlink = kzalloc(sizeof(*devlink) + priv_size, GFP_KERNEL);
> > if (!devlink)
> > return NULL;
> > +
> > + devlink->dev = dev;
> > devlink->ops = ops;
> > xa_init_flags(&devlink->snapshot_ids, XA_FLAGS_ALLOC);
> > write_pnet(&devlink->_net, net);
> > @@ -8810,12 +8812,9 @@ EXPORT_SYMBOL_GPL(devlink_alloc_ns);
> > * devlink_register - Register devlink instance
> > *
> > * @devlink: devlink
> > - * @dev: parent device
> > */
>
> This patch is converting devlink_alloc() to devlink_alloc_register().
>
> There are 2 APIs: devlink_alloc() and devlink_register().
> Both APIs can be used in a scenario,
> Where devlink_alloc() can be done by code written around
> one struct dev and used by another struct dev.
> or
> This scenario is not even a valid scenario?
devlink_alloc() is used to allocated netdev structures for newly
initialized device, it is not possible to share same devlink instance
between different devices.
>
> > -int devlink_register(struct devlink *devlink, struct device *dev)
> > +int devlink_register(struct devlink *devlink)
> > {
> > - WARN_ON(devlink->dev);
> > - devlink->dev = dev;
> > mutex_lock(&devlink_mutex);
> > list_add_tail(&devlink->list, &devlink_list);
> > devlink_notify(devlink, DEVLINK_CMD_NEW);
>
> Considering device registration has been moved to devlink_alloc().
> Can the remaining code of devlink_register() be also moved in devlink_alloc()?
The line "list_add_tail(&devlink->list, &devlink_list);" makes the
devlink instance visible to the devlink netlink users. We need to be
sure that it is happening when the device is already initialized, while
devlink_alloc() is performed usually as first line in .probe() routine.
This means that we can't combine alloc an register and
devlink_alloc_register() can't be valid scenario.
Thanks
>
> --pk
