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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 12:15:52 -0700
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On Wed, 2005-08-24 at 20:48 +0200, Roman Zippel wrote:
> Hi,
> 
> On Wed, 24 Aug 2005, john stultz wrote:
> 
> > 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
> > 
> > ?
> 
> No.
> 
> 	reference_time = xtime;
> 	system_time = xtime + error >> shift;
> 	gettimeofday = system_time + (cycle_offset * mult) >> shift;

Eh? In your example code from before you look to be keeping the
system_time and error values in shifted nsec units.

from your example:
>		// at init: system_update = update_cycles * mult;
> 		system_time += system_update;

and:
> 	error = system_time - (xtime.tv_nsec << shift);

This doesn't seem to make sense with the above.  Could you clarify?

thanks
-john