Re: [PATCH 17/26] cgroup/misc: Add notifier block list support for css events

[Kristen Carlson Accardi]

On Mon, 2022-11-14 at 12:42 -1000, Tejun Heo wrote:
> Hello,
> 
> On Fri, Nov 11, 2022 at 10:35:22AM -0800, Kristen Carlson Accardi
> wrote:
> > +/**
> > + * register_misc_cg_notifier() - Register for css callback events
> > + * @nb: notifier_block to register
> > + *
> > + * Context: Any context.
> > + */
> > +int register_misc_cg_notifier(struct notifier_block *nb)
> > +{
> > +       return
> > blocking_notifier_chain_register(&misc_cg_notify_list, nb);
> > +}
> > +EXPORT_SYMBOL_GPL(register_misc_cg_notifier);
> > +
> > +/**
> > + * unregister_misc_cg_notifier() - unregister for css callback
> > events
> > + * @nb: notifier_block to unregister
> > + *
> > + * Context: Any context.
> > + */
> > +int unregister_misc_cg_notifier(struct notifier_block *nb)
> > +{
> > +       return
> > blocking_notifier_chain_unregister(&misc_cg_notify_list, nb);
> > +}
> > +EXPORT_SYMBOL_GPL(unregister_misc_cg_notifier);
> 
> So, I'm not necessarily against this but wonder whether it'd be more
> straightforward to add sth like struct misc_res_ops which contains
> the
> optional callbacks and then have an array of pointers to the structs
> which
> are initialized / registered somehow. What do you think?
> 
> Thanks.
> 

Makes no difference to me TBH - I believe they will be functionally
equivalent and from a downstream user perspective equally as easy to
use, so whatever you think is easiest for you to maintain.