[PATCH] D40047: AMDGPU/GCN: Remove xnack from 801 and 810

[Tony Tye via Phabricator via llvm-commits]

t-tye added a comment.

In https://reviews.llvm.org/D40047#925606, @mareko wrote:

> In https://reviews.llvm.org/D40047#925599, @tstellar wrote:
>
> > Does this change break backwards compatibility with the gfx801 target?  If so, which ROCm version will I need to use with these changes?
>
>
> It depends on whether the KMD enables instruction replay. By default, the KMD enables it for compute rings, but I don't know if the ROCm userspace can override the setting.


The high level runtime does not have to override the setting to still choose to load and execute code without XNACK support. For example, the runtime may choose to pin all buffers and so know XNACK can never happen. This is what the ROCM OpenCL 1.2 runtime does for dGPUs even when that have demand paging enabled. I am not sure how APUs are supported.


https://reviews.llvm.org/D40047