2012-10-05 14:56:34

by Arnd Bergmann

Subject: [PATCH 06/16] mm/slob: use min_t() to compare ARCH_SLAB_MINALIGN

The definition of ARCH_SLAB_MINALIGN is architecture dependent
and can be either of type size_t or int. Comparing that value
with ARCH_KMALLOC_MINALIGN can cause harmless warnings on
platforms where they are different. Since both are always
small positive integer numbers, using the size_t type to compare
them is safe and gets rid of the warning.

Without this patch, building ARM collie_defconfig results in:

mm/slob.c: In function '__kmalloc_node':
mm/slob.c:431:152: warning: comparison of distinct pointer types lacks a cast [enabled by default]
mm/slob.c: In function 'kfree':
mm/slob.c:484:153: warning: comparison of distinct pointer types lacks a cast [enabled by default]
mm/slob.c: In function 'ksize':
mm/slob.c:503:153: warning: comparison of distinct pointer types lacks a cast [enabled by default]

Signed-off-by: Arnd Bergmann <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Pekka Enberg <[email protected]>
---
mm/slob.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/mm/slob.c b/mm/slob.c
index 45d4ca7..497c55e 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -428,7 +428,7 @@ out:
void *__kmalloc_node(size_t size, gfp_t gfp, int node)
{
unsigned int *m;
- int align = max(ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
+ int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
void *ret;

gfp &= gfp_allowed_mask;
@@ -481,7 +481,7 @@ void kfree(const void *block)

sp = virt_to_page(block);
if (PageSlab(sp)) {
- int align = max(ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
+ int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
unsigned int *m = (unsigned int *)(block - align);
slob_free(m, *m + align);
} else
@@ -500,7 +500,7 @@ size_t ksize(const void *block)

sp = virt_to_page(block);
if (PageSlab(sp)) {
- int align = max(ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
+ int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
unsigned int *m = (unsigned int *)(block - align);
return SLOB_UNITS(*m) * SLOB_UNIT;
} else
--
1.7.10

2012-10-05 16:46:23

by Christoph Lameter (Ampere)

Subject: Re: [PATCH 06/16] mm/slob: use min_t() to compare ARCH_SLAB_MINALIGN

On Fri, 5 Oct 2012, Arnd Bergmann wrote:

> Without this patch, building ARM collie_defconfig results in:
>
> mm/slob.c: In function '__kmalloc_node':
> mm/slob.c:431:152: warning: comparison of distinct pointer types lacks a cast [enabled by default]
> mm/slob.c: In function 'kfree':
> mm/slob.c:484:153: warning: comparison of distinct pointer types lacks a cast [enabled by default]
> mm/slob.c: In function 'ksize':
> mm/slob.c:503:153: warning: comparison of distinct pointer types lacks a cast [enabled by default]

Acked-by: Christoph Lameter <[email protected]>

2012-10-31 07:25:30

by Pekka Enberg

Subject: Re: [PATCH 06/16] mm/slob: use min_t() to compare ARCH_SLAB_MINALIGN

On Fri, 5 Oct 2012, Christoph Lameter wrote:

> On Fri, 5 Oct 2012, Arnd Bergmann wrote:
>
> > Without this patch, building ARM collie_defconfig results in:
> >
> > mm/slob.c: In function '__kmalloc_node':
> > mm/slob.c:431:152: warning: comparison of distinct pointer types lacks a cast [enabled by default]
> > mm/slob.c: In function 'kfree':
> > mm/slob.c:484:153: warning: comparison of distinct pointer types lacks a cast [enabled by default]
> > mm/slob.c: In function 'ksize':
> > mm/slob.c:503:153: warning: comparison of distinct pointer types lacks a cast [enabled by default]
>
> Acked-by: Christoph Lameter <[email protected]>

Applied, thanks!