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Date: Thu, 12 Mar 2009 08:50:34 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: john stultz <johnstul@us.ibm.com>
cc: Frans Pop <elendil@planet.nl>, linux-s390@vger.kernel.org,
       Roman Zippel <zippel@linux-m68k.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [BUG,2.6.28,s390] Fails to boot in Hercules S/390 emulator
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On Wed, 11 Mar 2009, john stultz wrote:
> Maybe a different way of expressing what we're calculating is the
> following:
> 
> xtime.tv_nsec = (clock->xtime_nsec + (1<<clock->shift)) >> clock->shift
> clock->xtime_nsec = (1<<clock->shift) 
> 			- (clock->xtime_nsec &((1<<clock->shift)-1)
> 
> In other words: The rounded up portion - the masked remainder in
> xtime_nsec.
> 
> Does that make sense?

Yes, now that my brain works again. I knew I was missing something.

You are definitely right: math _is_ hard :)

    tglx
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