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Subject: Re: [RFC - 0/9] Generic timekeeping subsystem  (v. B5)
From: john stultz <johnstul@us.ibm.com>
To: Christoph Lameter <clameter@engr.sgi.com>
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Date: Tue, 16 Aug 2005 17:17:29 -0700
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On Tue, 2005-08-16 at 17:14 -0700, Christoph Lameter wrote:
> On Tue, 16 Aug 2005, john stultz wrote:
> 
> > This is basically what I do in my patch. I directly apply the NTP
> > adjustment to the timesource interval, and periodically increment the
> > NTP state machine by the timesource interval when we accumulate it.
> 
> Is there some way to tell the NTP code how much the time_interpolator time 
> deviates from xtime?
> 
> If the NTP code would use getnstimeofday or 
> do_gettimeofday then it would already get interpolated time.

That seems a bit backwards, no?

> The curious issue in the current arrangement is that the interpolator 
> knows much more accurately how much time has passed between interrupts 
> than the timer interrupt but it has no time to make that information 
> available to the NTP code.

That is why I'm suggesting time_interpolator users to move to my code
(when they're ready, of course :).

thanks
-john