Re: [PATCH] bootmem.c: Avoid c90 declaration warning

From: Johannes Weiner
Date: Thu Jun 18 2009 - 18:01:25 EST


On Thu, Jun 18, 2009 at 01:24:10PM -0700, Andrew Morton wrote:
> On Thu, 18 Jun 2009 13:07:13 -0700
> Joe Perches <joe@xxxxxxxxxxx> wrote:
>
> > Signed-off-by: Joe Perches <joe@xxxxxxxxxxx>
> >
> > diff --git a/mm/bootmem.c b/mm/bootmem.c
> > index 282df0a..09d9c98 100644
> > --- a/mm/bootmem.c
> > +++ b/mm/bootmem.c
> > @@ -536,11 +536,13 @@ static void * __init alloc_arch_preferred_bootmem(bootmem_data_t *bdata,
> > return kzalloc(size, GFP_NOWAIT);
> >
> > #ifdef CONFIG_HAVE_ARCH_BOOTMEM
> > + {
> > bootmem_data_t *p_bdata;
> >
> > p_bdata = bootmem_arch_preferred_node(bdata, size, align, goal, limit);
> > if (p_bdata)
> > return alloc_bootmem_core(p_bdata, size, align, goal, limit);
> > + }
> > #endif
> > return NULL;
> > }
>
> Well yes.
>
> We'll be needing some tabs there.
>
> Unrelatedly, I'm struggling a bit with bootmem_arch_preferred_node().
> It's only defined if CONFIG_X86_32=y && CONFIG_NEED_MULTIPLE_NODES=y,
> but it gets called if CONFIG_HAVE_ARCH_BOOTMEM=y.
>
> Is this correct, logical and as simple as we can make it??

x86_32 numa is the only setter of HAVE_ARCH_BOOTMEM. I don't know why
this arch has a strict preference/requirement(?) for bootmem on node
0.

I found this mail from Yinghai

http://marc.info/?l=linux-kernel&m=123614990906256&w=2

where he says that it expects all bootmem on node zero but with the
current code and alloc_arch_preferred_bootmem() failing, we could fall
back to another node. Won't this break? Yinghai?

Otherwise, could we perhaps use something as simple as this?

diff --git a/arch/x86/include/asm/mmzone_32.h b/arch/x86/include/asm/mmzone_32.h
index ede6998..b68a672 100644
--- a/arch/x86/include/asm/mmzone_32.h
+++ b/arch/x86/include/asm/mmzone_32.h
@@ -92,8 +92,7 @@ static inline int pfn_valid(int pfn)

#ifdef CONFIG_NEED_MULTIPLE_NODES
/* always use node 0 for bootmem on this numa platform */
-#define bootmem_arch_preferred_node(__bdata, size, align, goal, limit) \
- (NODE_DATA(0)->bdata)
+#define bootmem_arch_preferred_node (NODE(0)->bdata)
#endif /* CONFIG_NEED_MULTIPLE_NODES */

#endif /* _ASM_X86_MMZONE_32_H */
diff --git a/mm/bootmem.c b/mm/bootmem.c
index 282df0a..0097fa2 100644
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -528,23 +528,6 @@ find_block:
return NULL;
}

-static void * __init alloc_arch_preferred_bootmem(bootmem_data_t *bdata,
- unsigned long size, unsigned long align,
- unsigned long goal, unsigned long limit)
-{
- if (WARN_ON_ONCE(slab_is_available()))
- return kzalloc(size, GFP_NOWAIT);
-
-#ifdef CONFIG_HAVE_ARCH_BOOTMEM
- bootmem_data_t *p_bdata;
-
- p_bdata = bootmem_arch_preferred_node(bdata, size, align, goal, limit);
- if (p_bdata)
- return alloc_bootmem_core(p_bdata, size, align, goal, limit);
-#endif
- return NULL;
-}
-
static void * __init ___alloc_bootmem_nopanic(unsigned long size,
unsigned long align,
unsigned long goal,
@@ -553,11 +536,15 @@ static void * __init ___alloc_bootmem_nopanic(unsigned long size,
bootmem_data_t *bdata;
void *region;

+ if (WARN_ON_ONCE(slab_is_available()))
+ return kzalloc(size, GFP_NOWAIT);
restart:
- region = alloc_arch_preferred_bootmem(NULL, size, align, goal, limit);
+#ifdef bootmem_arch_preferred_node
+ region = alloc_bootmem_core(bootmem_arch_preferred_node,
+ size, align, goal, limit);
if (region)
return region;
-
+#endif
list_for_each_entry(bdata, &bdata_list, list) {
if (goal && bdata->node_low_pfn <= PFN_DOWN(goal))
continue;
@@ -636,13 +623,11 @@ static void * __init ___alloc_bootmem_node(bootmem_data_t *bdata,
{
void *ptr;

- ptr = alloc_arch_preferred_bootmem(bdata, size, align, goal, limit);
- if (ptr)
- return ptr;
-
+#ifndef bootmem_arch_preferred_node
ptr = alloc_bootmem_core(bdata, size, align, goal, limit);
if (ptr)
return ptr;
+#endif

return ___alloc_bootmem(size, align, goal, limit);
}
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/