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Date: Tue, 20 Dec 2005 11:04:05 -0800
From: Julian Elischer <julian@elischer.org>
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To: Luigi Rizzo <rizzo@icir.org>
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Cc: current@freebsd.org
Subject: Re: td->td_critnest manipulations do not use atomic_add_int ?
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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?

>cheers
>luigi
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