xchg_acquire
mask = xchg_acquire(&vcpu->arch.irqs_pending_mask[1], 0);
mask = xchg_acquire(&vcpu->arch.irqs_pending_mask[0], 0);
if (xchg_acquire(&info->is_active, 1))
xchg_acquire(&lock->owner, rt_mutex_owner_encode(lock, owner));
xchg_acquire(p, owner & ~RT_MUTEX_HAS_WAITERS);
return xchg_acquire(ptr, new);
return xchg_acquire(ptr, new);