simple_lock(&pg->mdpage.pvh_lock);
pmap_pv_enter(struct vm_page *pg, struct pv_entry *pve, struct pmap *pm,    vaddr_t va, struct vm_page *pdep){	DPRINTF(PDB_FOLLOW|PDB_PV, ("pmap_pv_enter(%p, %p, %p, 0x%x, %p)\n",	    pg, pve, pm, va, pdep));	pve->pv_pmap	= pm;	pve->pv_va	= va;	pve->pv_ptp	= pdep;	simple_lock(&pg->mdpage.pvh_lock);	/* lock pv_head */	pve->pv_next = pg->mdpage.pvh_list;	pg->mdpage.pvh_list = pve;#ifdef PMAPDEBUG	if (pmap_check_alias(pve, va, 0))		Debugger();#endif	simple_unlock(&pg->mdpage.pvh_lock);	/* unlock, done! */}