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GPUOpen-Drivers / AMDVLK

AMD Open Source Driver For Vulkan
MIT License
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AMD_VULKAN_ICD has no effect when both RADV and AMDVLK are installed #222

Closed xuzhao9 closed 3 years ago

xuzhao9 commented 3 years ago

After installing amdvlk and radeon (libvulkan_radeon) driver together, the vulkan still loads RADV driver by default. I have placed the amd_icd.x86_64.json in /etc/vulkan/implicit_layer.d, and set the environment variable AMD_VULKAN_ICD to "AMDVLK", however, the vkcube program still uses RADV.

I don't find anything related to "AMD_VULKAN_ICD" environment variable in vulkan loader, so I am curious where is this environment variable respected and checked?

Platform: openSUSE Tumbleweed 20210307

jinjianrong commented 3 years ago

AMD_VULKAN_ICD is checked in https://github.com/GPUOpen-Drivers/xgl/blob/dev/icd/layers/vk_layer_switchable_graphics.cpp. Is the amd_icd.x86_64.json file generated according to the instruction: https://github.com/GPUOpen-Drivers/AMDVLK#build-driver-and-generate-json-files?

xuzhao9 commented 3 years ago

Yes, it is generated by the ninja compilation program. To be specific, this is the amd_icd.x86_64.json file I am using: https://pastebin.com/NZ9ZVSR4

Flakebi commented 3 years ago

Does the switchable graphics layer and amdvlk show up in the output of vulkaninfo?

xuzhao9 commented 3 years ago

Does the switchable graphics layer and amdvlk show up in the output of vulkaninfo?

Here is the output of vulkaninfo: https://pastebin.com/Lu1DgUcb. AMD switchable graphics layer appears but I don't find amdvlk.

Flakebi commented 3 years ago

Thanks for the output. That looks like it is already using amdvlk (GPU id : 0 (Unknown AMD GPU)). You can try AMD_VULKAN_ICD=RADV vulkaninfo and it should show a GPU that has RADV (and ACO) in its name.

xuzhao9 commented 3 years ago

Thanks for the output. That looks like it is already using amdvlk (GPU id : 0 (Unknown AMD GPU)). You can try AMD_VULKAN_ICD=RADV vulkaninfo and it should show a GPU that has RADV (and ACO) in its name.

Indeed as you said, after specifying AMD_VULKAN_ICD=RADV, vulkaninfo shows a GPU with RADV in its name. However, when I run AMD_VULKAN_ICD=AMDVLK vkcube, the program gives the following output:

WARNING: radv is not a conformant vulkan implementation, testing use only.
Selected GPU 0: Unknown AMD GPU, type: 2

Is it expected behavior?

Flakebi commented 3 years ago

Ah, this can be a bit confusing, indeed. The line Selected GPU 0: Unknown AMD GPU, type: 2 says it is using amdvlk as the vulkan driver. The line WARNING: radv is not a conformant vulkan implementation, testing use only. (which I’d say is a bit of a stretch, given the usage of radv ;)) is printed when the driver libraries get loaded, that is before the application chooses which driver to use and it doesn’t mean that radv is actually used, just the .so was loaded by the vulkan loader.

xuzhao9 commented 3 years ago

Ah, this can be a bit confusing, indeed. The line Selected GPU 0: Unknown AMD GPU, type: 2 says it is using amdvlk as the vulkan driver. The line WARNING: radv is not a conformant vulkan implementation, testing use only. (which I’d say is a bit of a stretch, given the usage of radv ;)) is printed when the driver libraries get loaded, that is before the application chooses which driver to use and it doesn’t mean that radv is actually used, just the .so was loaded by the vulkan loader.

I see, now it makes sense. Thanks!