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

[Dmitry Osipenko]

On 11/23/23 01:37, Dmitry Osipenko wrote:
> 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).

s/allocation/attachment/

Pages are still allocated by virtio_gpu_object_create().

-- 
Best regards,
Dmitry