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

[John Hubbard]

On 3/18/26 4:21 PM, Alexandre Courbot wrote:
> On Thu Mar 19, 2026 at 12:27 AM JST, 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.
> 
> Actually let's fix that afterwards, what I proposed above would
> introduce code that hasn't undergone review, and doesn't reduce the
> number of patches in the series so doesn't bring any benefit. I'll merge
> the series as-is for now.

For what it's worth, this avoided an email from me, to the effect of
"there is no such thing as a quick locking fixup, don't do this".

So, good. :)

thanks,
-- 
John Hubbard