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Date: Tue, 02 Jul 2013 21:08:36 +0300
From: Andriy Gapon <avg@FreeBSD.org>
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To: attilio@FreeBSD.org
Subject: Re: should_yield problem [Was: svn commit: r251322 - head/sys/kern]
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on 02/07/2013 20:52 Attilio Rao said the following:
> I was just pointing out that the real bug is not in the subtraction
> itself but on the hogticks comparison.
> This is because hogticks is not an absolute measurement but it
> represents really a ticks difference.
> In my opinion we should define hogticks as an unsigned int and add a
> small comment saying that it is a differential.
> This will fix the issue.

I think that my original suggestion is equivalently well if not more obvious.
This is a common knowledge:
http://en.wikipedia.org/wiki/Serial_number_arithmetic#General_Solution

distance = (signed)( i1 - i2 )

-- 
Andriy Gapon