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Subject: Re: [RFC - 0/9] Generic timekeeping subsystem  (v. B5)
From: john stultz <johnstul@us.ibm.com>
To: Roman Zippel <zippel@linux-m68k.org>
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Date: Wed, 24 Aug 2005 11:00:22 -0700
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On Wed, 2005-08-24 at 01:54 +0200, Roman Zippel wrote:
> Hi,
> 
> On Tue, 23 Aug 2005, john stultz wrote:
> 
> > I'm assuming gettimeofday()/clock_gettime() looks something like:
> >    xtime + (get_cycles()-last_update)*(mult+ntp_adj)>>shift
> 
> Where did you get the ntp_adj from? It's not in my example.
> gettimeofday() was in the previous mail: "xtime + (cycle_offset * mult +
> error) >> shift". The difference between system time and reference 
> time is really important. gettimeofday() returns the system time, NTP 
> controls the reference time and these two are synchronized regularly.
> I didn't see that anywhere in your example.

Ok, so then to clarify the above (as you mention gettimeofday uses
system_time), would your gettimeofday look something like:

gettiemofday():
	return (system_time + (cycle_offset * mult) + error)>> shift

?

thanks
-john