hpte_update(mm, addr, old, 0);
hpte_update(mm, addr, ptep, old, 0);
static inline int __ptep_test_and_clear_young(struct mm_struct *mm, unsigned long addr, pte_t *ptep){	unsigned long old;       	if ((pte_val(*ptep) & (_PAGE_ACCESSED | _PAGE_HASHPTE)) == 0)		return 0;	old = pte_update(ptep, _PAGE_ACCESSED);	if (old & _PAGE_HASHPTE) {		hpte_update(mm, addr, old, 0);		flush_tlb_pending();	}	return (old & _PAGE_ACCESSED) != 0;}