Re: [PATCH] s390/mm: Silence compiler warning when compiling without CONFIG_PGSTE

From: Heiko Carstens
Date: Mon Apr 08 2019 - 09:28:33 EST


On Mon, Apr 08, 2019 at 12:36:32PM +0200, Thomas Huth wrote:
> On 08/04/2019 09.09, David Hildenbrand wrote:
> > On 07.04.19 14:55, Thomas Huth wrote:
> >> If CONFIG_PGSTE is not set (e.g. when compiling without KVM), GCC complains:
> >>
> >> CC arch/s390/mm/pgtable.o
> >> arch/s390/mm/pgtable.c:413:15: warning: âpmd_alloc_mapâ defined but not
> >> used [-Wunused-function]
> >> static pmd_t *pmd_alloc_map(struct mm_struct *mm, unsigned long addr)
> >> ^~~~~~~~~~~~~
> >>
> >> Wrap the function with "#ifdef CONFIG_PGSTE" to silence the warning.
> >>
> >> Signed-off-by: Thomas Huth <thuth@xxxxxxxxxx>
> >> ---
> >> arch/s390/mm/pgtable.c | 2 ++
> >> 1 file changed, 2 insertions(+)
> >>
> >> diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
> >> index 8485d6dc2754..9ebd01219812 100644
> >> --- a/arch/s390/mm/pgtable.c
> >> +++ b/arch/s390/mm/pgtable.c
> >> @@ -410,6 +410,7 @@ static inline pmd_t pmdp_flush_lazy(struct mm_struct *mm,
> >> return old;
> >> }
> >>
> >> +#ifdef CONFIG_PGSTE
> >> static pmd_t *pmd_alloc_map(struct mm_struct *mm, unsigned long addr)
> >> {
> >> pgd_t *pgd;
> >> @@ -427,6 +428,7 @@ static pmd_t *pmd_alloc_map(struct mm_struct *mm, unsigned long addr)
> >> pmd = pmd_alloc(mm, pud, addr);
> >> return pmd;
> >> }
> >> +#endif
> >>
> >
> > We could also move the function down to the functions where it is used
>
> Yeah, I thought about that, too. Both have advantages:
>
> - If we keep the code here, "git blame" shows a nicer history of these
> lines
> - If we move the code, we need less #ifdefs
>
> I'll leave the decision to the maintainers... Martin, Heiko?

Applied without changes. Thanks!