td->td_critnest manipulations do not use atomic_add_int ?

John Baldwin jhb at
Tue Dec 20 11:22:53 PST 2005

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?


John Baldwin <jhb at>  <><
"Power Users Use the Power to Serve"  =

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