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Date: Tue, 20 Dec 2005 03:25:38 -0800
From: Luigi Rizzo <rizzo@icir.org>
To: current@freebsd.org
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Cc: 
Subject: td->td_critnest manipulations do not use atomic_add_int ?
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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.

cheers
luigi