td->td_critnest manipulations do not use atomic_add_int ?

Luigi Rizzo rizzo at
Tue Dec 20 03:25:40 PST 2005

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.


More information about the freebsd-current mailing list