td->td_critnest manipulations do not use atomic_add_int ?

[John Baldwin]

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.

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