[PATCH] Use const* parameters in mm.h

From: J.A. Magallon
Date: Thu Mar 23 2006 - 16:09:53 EST


On Thu, 23 Mar 2006 22:07:11 +0100, "J.A. Magallon" <jamagallon@xxxxxxx> wrote:

> On Thu, 23 Mar 2006 01:40:46 -0800, Andrew Morton <akpm@xxxxxxxx> wrote:
>
> >
> > ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.16/2.6.16-mm1/
> >
>

As they are inline, this gives the compiler wide space for optmizations.

--- linux-2.6.15-rc5-mm2.orig/include/linux/mm.h 2005-12-12 09:10:34.000000000 -0800
+++ linux-2.6.15-rc5-mm2/include/linux/mm.h 2005-12-14 14:39:50.000000000 -0800
@@ -464,7 +464,7 @@ void put_page(struct page *page);
#define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1)
#define ZONETABLE_MASK ((1UL << ZONETABLE_SHIFT) - 1)

-static inline unsigned long page_zonenum(struct page *page)
+static inline unsigned long page_zonenum(const struct page *page)
{
return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK;
}
@@ -472,20 +472,20 @@ static inline unsigned long page_zonenum
struct zone;
extern struct zone *zone_table[];

-static inline struct zone *page_zone(struct page *page)
+static inline struct zone *page_zone(const struct page *page)
{
return zone_table[(page->flags >> ZONETABLE_PGSHIFT) &
ZONETABLE_MASK];
}

-static inline unsigned long page_to_nid(struct page *page)
+static inline unsigned long page_to_nid(const struct page *page)
{
if (FLAGS_HAS_NODE)
return (page->flags >> NODES_PGSHIFT) & NODES_MASK;
else
return page_zone(page)->zone_pgdat->node_id;
}
-static inline unsigned long page_to_section(struct page *page)
+static inline unsigned long page_to_section(const struct page *page)
{
return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK;
}
@@ -519,7 +519,7 @@ static inline void set_page_links(struct
extern struct page *mem_map;
#endif

-static __always_inline void *lowmem_page_address(struct page *page)
+static __always_inline void *lowmem_page_address(const struct page *page)
{
return __va(page_to_pfn(page) << PAGE_SHIFT);
}
@@ -561,7 +561,7 @@ void page_address_init(void);
#define PAGE_MAPPING_ANON 1

extern struct address_space swapper_space;
-static inline struct address_space *page_mapping(struct page *page)
+static inline struct address_space *page_mapping(const struct page *page)
{
struct address_space *mapping = page->mapping;

@@ -572,7 +572,7 @@ static inline struct address_space *page
return mapping;
}

-static inline int PageAnon(struct page *page)
+static inline int PageAnon(const struct page *page)
{
return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0;
}
@@ -581,7 +581,7 @@ static inline int PageAnon(struct page *
* Return the pagecache index of the passed page. Regular pagecache pages
* use ->index whereas swapcache pages use ->private
*/
-static inline pgoff_t page_index(struct page *page)
+static inline pgoff_t page_index(const struct page *page)
{
if (unlikely(PageSwapCache(page)))
return page_private(page);
@@ -598,7 +598,7 @@ static inline void reset_page_mapcount(s
atomic_set(&(page)->_mapcount, -1);
}

-static inline int page_mapcount(struct page *page)
+static inline int page_mapcount(const struct page *page)
{
return atomic_read(&(page)->_mapcount) + 1;
}
@@ -606,7 +606,7 @@ static inline int page_mapcount(struct p
/*
* Return true if this page is mapped into pagetables.
*/
-static inline int page_mapped(struct page *page)
+static inline int page_mapped(const struct page *page)
{
return atomic_read(&(page)->_mapcount) >= 0;
}


--
J.A. Magallon <jamagallon()able!es> \ Software is like sex:
werewolf!able!es \ It's better when it's free
Mandriva Linux release 2006.1 (Cooker) for i586
Linux 2.6.15-jam20 (gcc 4.0.3 (4.0.3-1mdk for Mandriva Linux release 2006.1))

Attachment: signature.asc
Description: PGP signature