CALLB_CPR_SAFE
while (!(cp->cc_events & CALLB_CPR_SAFE))
if (ccp->cc_events & CALLB_CPR_SAFE) {
(cp)->cc_events |= CALLB_CPR_SAFE; \
(cp)->cc_events &= ~CALLB_CPR_SAFE; \
(cp)->cc_events |= CALLB_CPR_SAFE; \