Re: [PATCH v5 5/5] gpu: nova-core: gsp: add mutex locking to Cmdq

[Danilo Krummrich]

On Wed Mar 18, 2026 at 4:27 PM CET, Alexandre Courbot wrote:
> On Wed Mar 18, 2026 at 1:07 PM JST, Eliot Courtney wrote:
> <snip>
>> +    /// Returns the DMA handle of the command queue's shared memory region.
>> +    pub(crate) fn dma_handle(&self) -> DmaAddress {
>> +        self.inner.lock().gsp_mem.0.dma_handle()
>> +    }
>
> Just noticed that we now need to lock to get the DMA handle. It's
> inconsequential in practice but a bit inelegant.
>
> Since the DMA handle never changes, and is only ever needed during
> initialization, I think I will just insert a patch before this one that
> adds a `pub(super) dma_handle` member to `Cmdq`. That way we only need
> to obtain the handle at construction time and can get rid of this
> method, which keeps the public API focused on message handling.
>
> No need to resend, I will apply this patch on top of mine and merge.

It is a minor inconvinience, but it may indicate that dma::Coherent should
probaly support locking, i.e. you want to protect the data within the
dma::Coherent allocation, not the dma::Coherent object itself.