[PATCH 2.6.32-rc3] fix pcpu_embed_first_chunk() compile warnings

[PATCH 2.6.32-rc3] fix pcpu_embed_first_chunk() compile warnings

[Mikael Pettersson]

Compiling 2.6.32-rc3 on i686 I get the following new warnings:

mm/percpu.c: In function 'pcpu_embed_first_chunk':
mm/percpu.c:1873: warning: comparison of distinct pointer types lacks a cast
mm/percpu.c:1879: warning: format '%lx' expects type 'long unsigned int', but argument 2 has type 'size_t'

They are caused by 6ea529a2037ce662fc6bfa572b46d47407d08805
"make embedding first chunk allocator check vmalloc space size".

The first warning is because max() is applied to one operand of
type 'size_t' and another of type 'unsigned long'. Fix: cast the
second one to 'size_t'.

For the second warning: always use '%z' to format 'size_t' operands.

Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
---
 mm/percpu.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- linux-2.6.32-rc3/mm/percpu.c.~1~	2009-10-08 15:36:27.000000000 +0200
+++ linux-2.6.32-rc3/mm/percpu.c	2009-10-09 11:39:13.000000000 +0200
@@ -1870,13 +1870,13 @@ int __init pcpu_embed_first_chunk(size_t
 	max_distance = 0;
 	for (group = 0; group < ai->nr_groups; group++) {
 		ai->groups[group].base_offset = areas[group] - base;
-		max_distance = max(max_distance, ai->groups[group].base_offset);
+		max_distance = max(max_distance, (size_t)ai->groups[group].base_offset);
 	}
 	max_distance += ai->unit_size;
 
 	/* warn if maximum distance is further than 75% of vmalloc space */
 	if (max_distance > (VMALLOC_END - VMALLOC_START) * 3 / 4) {
-		pr_warning("PERCPU: max_distance=0x%lx too large for vmalloc "
+		pr_warning("PERCPU: max_distance=0x%zx too large for vmalloc "
 			   "space 0x%lx\n",
 			   max_distance, VMALLOC_END - VMALLOC_START);
 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK

Re: [PATCH 2.6.32-rc3] fix pcpu_embed_first_chunk() compile warnings

[Tejun Heo]

Mikael Pettersson wrote:
> Compiling 2.6.32-rc3 on i686 I get the following new warnings:
> 
> mm/percpu.c: In function 'pcpu_embed_first_chunk':
> mm/percpu.c:1873: warning: comparison of distinct pointer types lacks a cast
> mm/percpu.c:1879: warning: format '%lx' expects type 'long unsigned int', but argument 2 has type 'size_t'
> 
> They are caused by 6ea529a2037ce662fc6bfa572b46d47407d08805
> "make embedding first chunk allocator check vmalloc space size".
> 
> The first warning is because max() is applied to one operand of
> type 'size_t' and another of type 'unsigned long'. Fix: cast the
> second one to 'size_t'.
> 
> For the second warning: always use '%z' to format 'size_t' operands.
> 
> Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>

For some reason, I've been thinking this was linux-next specific and
committed about the same patch there, commit 3cbeae2f, a while ago.
The only difference was use of max_t() instead of size_t cast.  I
think max_t() is cleaner there and will cherry pick the patch from
linux-next.

Thanks.

-- 
tejun