Re: [PATCH] Greatly improve TSC calibration using a delayedworkqueue

From: Andi Kleen
Date: Tue Nov 09 2010 - 08:44:05 EST


> Interesting. Thanks for pointing that out! Couldn't I just start the
> calibration after fs_initcall (when the hpet_late_init runs) to avoid
> this as well?

Yes that probably would work. Or use the barrier infrastructure
in workqueue.c

>
> > Another issue may be races against suspend, but that may be too
> > obscure.
>
> Yea, that seems fairly obscure. Basically you'd have to suspend in the
> first second as the system came up. In that case the code will throw out
> any calibration refinement that's over 1% off of the initial boot
> calibration, so I think this is ok trade off.

It may happen with opportunistic suspend if the system boots very fast.

-Andi
--
ak@xxxxxxxxxxxxxxx -- Speaking for myself only.
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