> On 28 Nov 2025, at 08:08, Philipp Stanner <[email protected]> wrote:
>
> On Mon, 2025-11-24 at 09:49 -0300, Daniel Almeida wrote:
>> Hi Phillipp,
>>
>>> On 18 Nov 2025, at 10:25, Philipp Stanner <[email protected]> wrote:
>>>
>>> dma_fence is a synchronization mechanism which is needed by virtually
>>> all GPU drivers.
>>>
>
> […]
>
>>> +#[pin_data]
>>> +pub struct DmaFence<T> {
>>> + /// The actual dma_fence passed to C.
>>> + #[pin]
>>> + inner: Opaque<bindings::dma_fence>,
>>> + /// User data.
>>> + #[pin]
>>> + data: T,
>>
>> Same here: we should probably deref to this type.
>
> Oh, wait.
>
> There's another problem:
>
> done_fences are created by JQ and returned to the driver. The JQ
> doesn't need to stuff any data into those fences (it just wants to
> signal them, and register events on done_fences coming from other JQs).
>
> So I was about to investigate how we could have a DmaFence<()> to make
> the data optional (see the following patch, there I still use an i32 as
> dummy data).
>
> Is that compatible with Deref?
> Ideas?
>
>
> P.
>
It will just Deref to (). Not a problem.
— Daniel
