static void prepare_pmd_huge_pte(pgtable_t pgtable,
				 struct mm_struct *mm)
{
	assert_spin_locked(&mm->page_table_lock);

	/* FIFO */
	if (!mm->pmd_huge_pte)
		INIT_LIST_HEAD(&pgtable->lru);
	else
		list_add(&pgtable->lru, &mm->pmd_huge_pte->lru);
	mm->pmd_huge_pte = pgtable;
}
static void prepare_pmd_huge_pte(pgtable_t pgtable,
				 struct mm_struct *mm)
{
	assert_spin_locked(&mm->page_table_lock);

	 
	if (!mm->pmd_huge_pte)
		INIT_LIST_HEAD(&pgtable->lru);
	else
		list_add(&pgtable->lru, &mm->pmd_huge_pte->lru);
	mm->pmd_huge_pte = pgtable;
}