2019-04-07 12:56:05

by Thomas Huth

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

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: ‘pmd_alloc_map’ 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 <[email protected]>
---
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

pmd_t pmdp_xchg_direct(struct mm_struct *mm, unsigned long addr,
pmd_t *pmdp, pmd_t new)
--
2.21.0

2019-04-08 07:10:19

by David Hildenbrand

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

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: ‘pmd_alloc_map’ 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 <[email protected]>
> ---
> 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

Reviewed-by: David Hildenbrand <[email protected]>

--

Thanks,

David / dhildenb

2019-04-08 10:37:35

by Thomas Huth

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

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: ‘pmd_alloc_map’ 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 <[email protected]>
>> ---
>> 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?

> Reviewed-by: David Hildenbrand <[email protected]>

Thanks,
Thomas

2019-04-08 14:09:16

by Heiko Carstens

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

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: ‘pmd_alloc_map’ 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 <[email protected]>
> >> ---
> >> 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!