xe vs amdgpu userptr handling

[Maíra Canal]

Adding another point to this discussion, would it make sense to somehow
create a generic structure that all drivers, including shmem drivers, 
could use it?

Best Regards,
- Maíra

On 2/7/24 03:56, Dave Airlie wrote:
> I'm just looking over the userptr handling in both drivers, and of
> course they've chosen different ways to represent things. Again this
> is a divergence that is just going to get more annoying over time and
> eventually I'd like to make hmm/userptr driver independent as much as
> possible, so we get consistent semantics in userspace.
> 
> AFAICS the main difference is that amdgpu builds the userptr handling
> inside a GEM object in the kernel, whereas xe doesn't bother creating
> a holding object and just handles things directly in the VM binding
> code.
> 
> Is this just different thinking at different times here?
> like since we have VM BIND in xe, it made sense not to bother creating
> a gem object for userptrs?
> or is there some other advantages to going one way or the other?
> 
> Dave.