Idea Raised For Reducing The Size Of The AMDGPU Driver With Its Massive Header Files

[phoronix]

Phoronix: Idea Raised For Reducing The Size Of The AMDGPU Driver With Its Massive Header Files

Following the weekend news of the AMDGPU kernel driver becoming too large that it's causing the Plymouth boot splash screen on slower Linux systems to time-out, longtime AMD Linux graphics driver engineer Marek Olšák expressed a new idea for helping to reduce some bloat from this AMD kernel graphics driver...

https://www.phoronix.com/news/AMDGPU-Headers-Repo-Idea

[rhbvkleef]

I have to say, I'm not a big fan of moving the AMDGPU headers into a separate repository. Pruning the the headers and eliminating the unused bits seems to me as a much more sane solution to this problem.

Of course an even better solution would be to not store generated code in the kernel tree at all, and store the program that generates that source in stead, though that might prove difficult in the case of AMDGPU. I am not sure if that program/those programs are publicly available.

[oleid]

Okay, that's repo bloat. But how does this affect the alleged binary size bloat? It is not that those headers result in unused symbols, is it?

[cl333r]

Or maybe let the AMD devs port to the open source driver the remaining important stuff (if any) not yet present in the open source driver and then remove AMDGPU altogether.

[DanL]

Get rid of plymouth or at least its fancy boot splash screens. Problem solved.

[intelfx]

Okay, that's repo bloat. But how does this affect the alleged binary size bloat? It is not that those headers result in unused symbols, is it?

That’s exactly what I said in the last comment thread on this topic

[Blisterexe]

Get rid of plymouth or at least its fancy boot splash screens. Problem solved.

Plymouth's fancy splash screens contribute considerably to linux feeling polished or good to the average person, as silly as that might seem

[coder]

I have to say, I'm not a big fan of moving the AMDGPU headers into a separate repository. Pruning the the headers and eliminating the unused bits seems to me as a much more sane solution to this problem.

I think some of what he was proposing to prune was the documentation they contain. If that's needed to figure out what the definitions mean and how to use them, then you'd want that information to be maintained somewhere. If just the needed definitions are in the kernel tree, then these should be derived from the full headers that should live elsewhere.

Of course an even better solution would be to not store generated code in the kernel tree at all, and store the program that generates that source in stead, though that might prove difficult in the case of AMDGPU. I am not sure if that program/those programs are publicly available.

The headers are generated from their hardware design sources. They're not going to release those, and they'd bloat the tree way worse than the existing headers, if that did happen.

[coder]

Okay, that's repo bloat. But how does this affect the alleged binary size bloat? It is not that those headers result in unused symbols, is it?

What about some way to selectively determine what can be compiled with -Os ? By compiling some parts of the driver that way, you might even achieve faster runtimes! This wouldn't only be applicable to AMD's GPU driver, either.

[loganj]

i'm a bit confuse
are the headers in the final driver after compilation?
i was under the impresion that the headers files are only during compilation
if the are not in the finale driver whats the point in moving/trim them?