LWP_MP_VNLRU
if (lp->lwp_mpflags & LWP_MP_VNLRU) {
atomic_clear_int(&lp->lwp_mpflags, LWP_MP_VNLRU);
if (lp->lwp_mpflags & LWP_MP_VNLRU) {
atomic_clear_int(&lp->lwp_mpflags, LWP_MP_VNLRU);
atomic_set_int(&td->td_lwp->lwp_mpflags, LWP_MP_VNLRU);
#define LWP_MP_URETMASK (LWP_MP_WEXIT | LWP_MP_VNLRU)