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From: John Baldwin <jhb@freebsd.org>
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Cc: Luigi Rizzo <rizzo@icir.org>, Julian Elischer <julian@elischer.org>,
	current@freebsd.org
Subject: Re: td->td_critnest manipulations do not use atomic_add_int ?
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On Tuesday 20 December 2005 02:04 pm, Julian Elischer wrote:
> Luigi Rizzo wrote:
> >as in the subject... i see that td->td_critnest (used to determine
> >whether a thread can be preempted or not) is manipulated using
> >plain ++ or -- instruction instead of the atomic_add_int().
> >
> >I wonder if declaring it as volatile and possibly its
> >usage patterns are enough to make the two things equivalent
> >on all architectures.
>
> is td ever != curthread?

No.

-- 
John Baldwin <jhb@FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
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