Re: [PATCH v3 1/2] x86/vdso: Move mult and shift into struct vgtod_ts

From: Thomas Gleixner
Date: Mon Jun 24 2019 - 05:40:07 EST


Alexander,

On Mon, 24 Jun 2019, Sverdlin, Alexander (Nokia - DE/Ulm) wrote:
> On 23/06/2019 12:18, Thomas Gleixner wrote:
> > The alternative solution for this is what Vincenzo has in his unified VDSO
> > patch series:
> >
> > https://lkml.kernel.org/r/20190621095252.32307-1-vincenzo.frascino@xxxxxxx
> >
> > It leaves the data struct unmodified and has a separate array for the raw
> > clock. That does not have the side effects at all.
> >
> > I'm in the process of merging that series and I actually adapted your
> > scheme to the new unified infrastructure where it has exactly the same
> > effects as with your original patches against the x86 version.
>
> please let me know if I need to rework [2/2] based on some not-yet-published
> branch of yours.

I've pushed it out now to

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/vdso

The generic VDSO library has the support for RAW already with that separate
array. Testing would be welcomed!

Feel free to experiment with moving mult/shift again. Maybe you find a way
to mitigate the effects and make it all magically faster. :)

Thanks,

tglx