Re: [PATCH v18 24/26] drm/virtio: Attach shmem BOs dynamically

[Dmitry Osipenko]

On 11/13/23 12:57, Boris Brezillon wrote:
> On Mon, 30 Oct 2023 02:02:03 +0300
> Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx> wrote:
> 
>> Prepare for addition of memory shrinker support by attaching shmem pages
>> to host dynamically on first use. Previously the attachment vq command
>> wasn't fenced and there was no vq kick made in the BO creation code path,
>> hence the attachment already was happening dynamically, but implicitly.
>> Making attachment explicitly dynamic will allow to simplify and reuse more
>> code when shrinker will be added. The virtio_gpu_object_shmem_init() now
>> works under the held reservation lock, which will be important to have for
>> shrinker to avoid moving pages while they are in active use by the driver.
> Ah, this commit might actually help getting rid of the workaround
> introduced in "drm/shmem-helper: Add common memory shrinker".

Not really. The virtio_gpu_free_object() is unchanged, it's only
allocation that is being deferred and it's only done for a one BO type
(virtio-gpu has multiple BO types).

-- 
Best regards,
Dmitry