fuwordadd64
uint64_t (*fuwordadd64)(volatile uint64_t *, uint64_t v);
pmap->fuwordadd64 = std_fuwordadd64;
return curthread->td_proc->p_vmspace->vm_pmap.fuwordadd64(base, v);
uint64_t fuwordadd64(volatile uint64_t *p, uint64_t val);