From: Andi Kleen <ak@suse.de>
To: "Jan Beulich" <JBeulich@novell.com>
Subject: Re: [PATCH 13/39] NLKD/x86-64 - time adjustment
Date: Fri, 11 Nov 2005 03:12:15 +0100
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On Thursday 10 November 2005 15:23, Jan Beulich wrote:

>
> >Please remove the ifdefs too.  64bit HPET support would be fine, but
> >only as a runtime mechanism, not compile time.
>
> This I added only for the purpose of not affecting existing code in
> existing configurations. If the code is generally acceptable, then I'll be
> more than happy to convert it.

We can't use 64bit HPET everywhere because quite some chipsets only
support 32bit HPET. So it has to be a runtime switch depending on the 
capabilities of the hardware.

>
> >Can you remove debugger_jiffies please?
> >The code has to handle long delays anyways (e.g. if someone uses a target
> >probe), so we cannot rely on such hacks anyways.
>
> As above, I introduced this only to not affect existing code. If the added
> latency is no problem, then of course only the overflow safe code path
> should be kept, and then debugger_jiffies is completely unnecessary.

Hmm - didn't notice anything particularly slow. Or what were you thinking 
about regarding the latency? And it should only run at each timer interrupt,
so it isn't a fast path. So I guess it's best to run it always.

-Andi
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