AMD User Queue Mesa Support Merged For Linux - Submitting Work Directly To The GPU

[phoronix]

Phoronix: AMD User Queue Mesa Support Merged For Linux - Submitting Work Directly To The GPU

After an exciting day yesterday of Vulkan 1.4 driver support arriving in Mesa 25.0 drivers, there is more exciting code that was merged today for Mesa 25.0: the AMDGPU code now allows for user queue support on the latest Linux kernels for submitting rendering work directly to the GPU hardware...

https://www.phoronix.com/news/Mesa-25.0-AMDGPU-User-Queue

[Kjell]

AMD_USERQ should be set to 1 and supported Kernel should be used.

Are there any specific kernel patches/version for this to work?

[marek]

Are there any specific kernel patches/version for this to work?

It also depends on unreleased firmware. It's still experimental.

[Kjell]

It also depends on unreleased firmware. It's still experimental.

Understandable

In the future, does it make sense to launch the entire Wayland compositor with AMD_USERQ to achieve the best 3D performance/latency with subsequent processes?

[Mitch]

It also depends on unreleased firmware. It's still experimental.

Please excuse my stupid question.
So if you have the Hardware, the Kernel, and the MESA versions, and the switches enabled, what's left? Does software (Desktops, Browsers, Videogames) need to purposefully use this new feature and potentially rewrite some things, or does this instead automatically change how existing things work under the hood?

[nuetzel]

It also depends on unreleased firmware. It's still experimental.

Hello mareko ,

starting with gfx8+ or later?

[pac2000]

Please excuse my stupid question.
So if you have the Hardware, the Kernel, and the MESA versions, and the switches enabled, what's left? Does software (Desktops, Browsers, Videogames) need to purposefully use this new feature and potentially rewrite some things, or does this instead automatically change how existing things work under the hood?

The applications would need to either be rewritten, or the compiler might be able take advantage of it via libraries, depending on how it is implemented. So would need to be recompiled. But even if that was possible, the compiler would have to be rewritten.

This is mainly for new games or applications to increase their capabilities and speed at which they can interact with the GPU. Imagine a VM manager being able to pass through the graphics capabilities to a virtual machine. Or create a VM driver that translates to the user queue. This would provide greater graphic capabilities within the VM. Which has been lacking, and restricted to basic graphics. So it's very good news when everything catches up, and gives AMD an advantage over Nvidia.

[MrCooper]

In the future, does it make sense to launch the entire Wayland compositor with AMD_USERQ to achieve the best 3D performance/latency with subsequent processes?

Yes, this will make sense for everything. Presumably it'll become the default at some point once the kinks are ironed out.

I'm actually pretty psyched about this, it should allow getting the full benefit of my mutter work described in https://blogs.gnome.org/shell-dev/20...nsive-clients/ with AMD GPUs.

So if you have the Hardware, the Kernel, and the MESA versions, and the switches enabled, what's left?

Per the post you quoted, getting the needed firmware. Since that's unreleased, nobody outside of AMD can play with this just yet.

Does software (Desktops, Browsers, Videogames) need to purposefully use this new feature and potentially rewrite some things, or does this instead automatically change how existing things work under the hood?

The latter.

starting with gfx8+ or later?

AFAIK as things stand now, this will only be supported with RDNA3+. As it happens, I'm in the process of switching to a Zen4 + RDNA3 laptop for my main machine, good timing.

[dev_null]

Right move, I believe inspired by io_uring. In the end they will invent shared video memory and msdos b800:0000 address

[patrick1946]

Is that like io_uring minimizing kernel switches or is this actually a driver in the firmware running on the GPU?