She answered that in her blog post that the Phoronix article links to:

Which GPUs does this work with? Is it only AMD GPUs?

Whether or not your GPU can benefit from it depends on the kernel driver - more specifically, whether it sets up the dmem cgroup controller.

amdgpu and xe both have support for the dmem cgroup controller already. In theory, Intel GPUs running the xe kernel driver should benefit as well, although I’m not sure anyone tested this yet.

For nouveau, I have sent a patch for dmem cgroup support to the mailing lists. This patch is also included in my development branch, so if you use my AUR package it should work. In other cases, you will need to wait for the patch to be picked up by your distribution, or apply it yourself.

The proprietary NVIDIA kernel modules do not support dmem cgroups yet, so this won’t work there.