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Date:   Wed, 4 May 2022 14:25:58 +0200
From:   Michal =?iso-8859-1?Q?Koutn=FD?= <mkoutny@suse.com>
To:     "T.J. Mercier" <tjmercier@google.com>
Cc:     Tejun Heo <tj@kernel.org>, Zefan Li <lizefan.x@bytedance.com>,
        Johannes Weiner <hannes@cmpxchg.org>, daniel@ffwll.ch,
        hridya@google.com, christian.koenig@amd.com, jstultz@google.com,
        tkjos@android.com, cmllamas@google.com, surenb@google.com,
        kaleshsingh@google.com, Kenny.Ho@amd.com,
        skhan@linuxfoundation.org, kernel-team@android.com,
        linux-kernel@vger.kernel.org, cgroups@vger.kernel.org
Subject: Re: [PATCH v6 2/6] cgroup: gpu: Add a cgroup controller for
 allocator attribution of GPU memory
Message-ID: <20220504122558.GB24172@blackbody.suse.cz>
References: <20220502231944.3891435-1-tjmercier@google.com>
 <20220502231944.3891435-3-tjmercier@google.com>
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Hello.

On Mon, May 02, 2022 at 11:19:36PM +0000, "T.J. Mercier" <tjmercier@google.com> wrote:
> This patch adds APIs to:
> -allow a device to register for memory accounting using the GPU cgroup
> controller.
> -charge and uncharge allocated memory to a cgroup.

Is this API for separately built consumers?
The respective functions should be exported (EXPORT_SYMBOL_GPL) if I
haven't missed anything.

> +#ifdef CONFIG_CGROUP_GPU
> + /* The GPU cgroup controller data structure */
> +struct gpucg {
> +	struct cgroup_subsys_state css;
> +
> +	/* list of all resource pools that belong to this cgroup */
> +	struct list_head rpools;
> +};
> +
> +/* A named entity representing bucket of tracked memory. */
> +struct gpucg_bucket {
> +	/* list of various resource pools in various cgroups that the bucket is part of */
> +	struct list_head rpools;
> +
> +	/* list of all buckets registered for GPU cgroup accounting */
> +	struct list_head bucket_node;
> +
> +	/* string to be used as identifier for accounting and limit setting */
> +	const char *name;
> +};

Do these struct have to be defined "publicly"?
I.e. the driver code could just work with gpucg and gpucg_bucket
pointers.

> +int gpucg_register_bucket(struct gpucg_bucket *bucket, const char *name)

...and the registration function would return a pointer to newly
(internally) allocated gpucg_bucket.

Regards,
Michal