On Wed, Jun 07, 2017 at 02:47:32PM +0100, Will Deacon wrote:
> On Wed, May 17, 2017 at 04:23:34PM +0100, Punit Agrawal wrote:
> > --- a/arch/arm64/mm/hugetlbpage.c
> > +++ b/arch/arm64/mm/hugetlbpage.c
> > @@ -136,36 +136,27 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned
> > long addr)
> > {
> > pgd_t *pgd;
> > pud_t *pud;
> > - pmd_t *pmd = NULL;
> > - pte_t *pte = NULL;
> > + pmd_t *pmd;
> >
> > pgd = pgd_offset(mm, addr);
> > pr_debug("%s: addr:0x%lx pgd:%p\n", __func__, addr, pgd);
> > if (!pgd_present(*pgd))
> > return NULL;
> > +
> > pud = pud_offset(pgd, addr);
> > - if (!pud_present(*pud))
> > + if (pud_none(*pud))
> > return NULL;
>
> Do you actually need this special case?
>
> > -
> > - if (pud_huge(*pud))
> > + /* swap or huge page */
> > + if (!pud_present(*pud) || pud_huge(*pud))
>
> ... couldn't you just add a '|| pud_none(*pud)' in here?
>
> > return (pte_t *)pud;
But then you no longer return NULL if *pud == 0.
--
Catalin
