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;
Message-ID: <6f7afaa6811cbda30d12c38d73d4b261ab733a9f.camel@linux.intel.com>
Subject: Re: [PATCH 17/26] cgroup/misc: Add notifier block list support for
 css events
From:   Kristen Carlson Accardi <kristen@linux.intel.com>
To:     Tejun Heo <tj@kernel.org>
Cc:     jarkko@kernel.org, dave.hansen@linux.intel.com,
        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
Date:   Mon, 14 Nov 2022 15:10:05 -0800
In-Reply-To: <Y3LES3rUIZ/PtwzV@slm.duckdns.org>
References: <20221111183532.3676646-1-kristen@linux.intel.com>
         <20221111183532.3676646-18-kristen@linux.intel.com>
         <Y3LES3rUIZ/PtwzV@slm.duckdns.org>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
User-Agent: Evolution 3.44.4 (3.44.4-2.fc36) 
MIME-Version: 1.0
Precedence: bulk

On Mon, 2022-11-14 at 12:42 -1000, Tejun Heo wrote:
> Hello,
>=20
> 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)
> > +{
> > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0return
> > 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)
> > +{
> > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0return
> > blocking_notifier_chain_unregister(&misc_cg_notify_list, nb);
> > +}
> > +EXPORT_SYMBOL_GPL(unregister_misc_cg_notifier);
>=20
> 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?
>=20
> Thanks.
>=20

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.