Re: FOR REVIEW: New x86-64 vsyscall vgetcpu()

Benjamin Herrenschmidt
2006-06-15T23:18:36Z

> PowerPC has similar issues and could use VDSO/vsyscal to implement
> vgetcpu() as well. So we should get Ben Herrenschmidt involved to insure
> that we have a cross platform solution.

Except that I haven't yet found a way to pass the information to the
vdso... in the past, there used to be an SPRG that was readable by
userland that I could have used but I can't see that working on recent
CPUs. The PIR isn't quite portable (though the vDSO can have per-cpu
model) and we don't quite know for sure what's in there, especially on
shared processor machines.

Any idea ?

Ben.