Am 10.07.20 um 14:43 schrieb Jason Gunthorpe:
On Thu, Jul 09, 2020 at 10:09:11AM +0200, Daniel Vetter wrote:
Hi Jason,
Below the paragraph I've added after our discussions around dma-fences
outside of drivers/gpu. Good enough for an ack on this, or want something
changed?
Thanks, Daniel
+ * Note that only GPU drivers have a reasonable excuse for both requiring
+ * &mmu_interval_notifier and &shrinker callbacks at the same time as having to
+ * track asynchronous compute work using &dma_fence. No driver outside of
+ * drivers/gpu should ever call dma_fence_wait() in such contexts.
I was hoping we'd get to 'no driver outside GPU should even use
dma_fence()'
My last status was that V4L could come use dma_fences as well.
I'm not 100% sure, but wouldn't MMU notifier + dma_fence be a valid use
case for things like custom FPGA interfaces as well?
Is that not reasonable?
When your annotations once anything uses dma_fence it has to assume
the worst cases, right?
Well a defensive approach is usually the best idea, yes.
Christian.
Jason
