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

[Tejun Heo]

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.

-- 
tejun