Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Sender: Tejun Heo <htejun@gmail.com>
Date:   Mon, 14 Nov 2022 12:42:19 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Kristen Carlson Accardi <kristen@linux.intel.com>
Cc:     jarkko@kernel.org, dave.hansen@linux.kernel.org,
        linux-kernel@vger.kernel.org, linux-sgx@vger.kernel.org,
        cgroups@vger.kernel.org, Zefan Li <lizefan.x@bytedance.com>,
        Johannes Weiner <hannes@cmpxchg.org>, zhiquan1.li@intel.com
Subject: Re: [PATCH 17/26] cgroup/misc: Add notifier block list support for
 css events
Message-ID: <Y3LES3rUIZ/PtwzV@slm.duckdns.org>
References: <20221111183532.3676646-1-kristen@linux.intel.com>
 <20221111183532.3676646-18-kristen@linux.intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20221111183532.3676646-18-kristen@linux.intel.com>
Precedence: bulk

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