More FUTEX2 Additions Being Worked On For The Linux Kernel

[phoronix]

Phoronix: More FUTEX2 Additions Being Worked On For The Linux Kernel

Merged back in 2021 with Linux 5.16 was the FUTEX2 code to help with Linux gaming needs particularly around Steam Play. There were plans to further extend FUTEX2 and now two years later there's been recent patches working out more enhancements to this interface...

https://www.phoronix.com/news/More-FUTEX2-Linux

[guglovich]

I was under the impression that FUTEX 1 was in the core and FUTEX 2 was separate.

[Namelesswonder]

I was under the impression that FUTEX 1 was in the core and FUTEX 2 was separate.

It's the opposite.

The futex syscall in the kernel can't wait on multiple futexes, which doesn't make it ideal for wine as Windows supports multiple too.

The original patch set that overloaded the futex syscall to allow for waiting on multiple futexes has retroactively been called "futex1", and it never made it into the kernel. However, nobody should still be trying to run that old patch as futex2 is essentially the same with some modifications to make it a separate syscall.

Futex1 can be added back in however in an external patch that piggybacks off of the futex2 syscall, in case you have any old software or old wine/protons that were compiled for it.

[JEBjames]

Michael

"some missing flaga" should be "some missing flags"

[Hi-Angel]

Michael

"some missing flaga" should be "some missing flags"

lol I thought it is slang of some sort

[NotMine999]

lol I thought it is slang of some sort

The tech industry likes to invent catchy new names for stuff. Performant. Spectre. RetBleed. Google.

[Hi-Angel]

So, does anybody know if current WINE makes use of futex2? I couldn't find any information about that, only that it is used in Proton, which does not necessarily mean it's available in WINE as well.

[F.Ultra]

So, does anybody know if current WINE makes use of futex2? I couldn't find any information about that, only that it is used in Proton, which does not necessarily mean it's available in WINE as well.

AFAIK regular Wine does not yet use it