forked from mirrors/linux
		
	There is a memory waste problem if we define field on struct page_ext by hard-coding. Entry size of struct page_ext includes the size of those fields even if it is disabled at runtime. Now, extra memory request at runtime is possible so page_owner don't need to define it's own fields by hard-coding. This patch removes hard-coded define and uses extra memory for storing page_owner information in page_owner. Most of code are just mechanical changes. Link: http://lkml.kernel.org/r/1471315879-32294-7-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			85 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			85 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
#ifndef __LINUX_PAGE_EXT_H
 | 
						|
#define __LINUX_PAGE_EXT_H
 | 
						|
 | 
						|
#include <linux/types.h>
 | 
						|
#include <linux/stacktrace.h>
 | 
						|
#include <linux/stackdepot.h>
 | 
						|
 | 
						|
struct pglist_data;
 | 
						|
struct page_ext_operations {
 | 
						|
	size_t offset;
 | 
						|
	size_t size;
 | 
						|
	bool (*need)(void);
 | 
						|
	void (*init)(void);
 | 
						|
};
 | 
						|
 | 
						|
#ifdef CONFIG_PAGE_EXTENSION
 | 
						|
 | 
						|
/*
 | 
						|
 * page_ext->flags bits:
 | 
						|
 *
 | 
						|
 * PAGE_EXT_DEBUG_POISON is set for poisoned pages. This is used to
 | 
						|
 * implement generic debug pagealloc feature. The pages are filled with
 | 
						|
 * poison patterns and set this flag after free_pages(). The poisoned
 | 
						|
 * pages are verified whether the patterns are not corrupted and clear
 | 
						|
 * the flag before alloc_pages().
 | 
						|
 */
 | 
						|
 | 
						|
enum page_ext_flags {
 | 
						|
	PAGE_EXT_DEBUG_POISON,		/* Page is poisoned */
 | 
						|
	PAGE_EXT_DEBUG_GUARD,
 | 
						|
	PAGE_EXT_OWNER,
 | 
						|
#if defined(CONFIG_IDLE_PAGE_TRACKING) && !defined(CONFIG_64BIT)
 | 
						|
	PAGE_EXT_YOUNG,
 | 
						|
	PAGE_EXT_IDLE,
 | 
						|
#endif
 | 
						|
};
 | 
						|
 | 
						|
/*
 | 
						|
 * Page Extension can be considered as an extended mem_map.
 | 
						|
 * A page_ext page is associated with every page descriptor. The
 | 
						|
 * page_ext helps us add more information about the page.
 | 
						|
 * All page_ext are allocated at boot or memory hotplug event,
 | 
						|
 * then the page_ext for pfn always exists.
 | 
						|
 */
 | 
						|
struct page_ext {
 | 
						|
	unsigned long flags;
 | 
						|
};
 | 
						|
 | 
						|
extern void pgdat_page_ext_init(struct pglist_data *pgdat);
 | 
						|
 | 
						|
#ifdef CONFIG_SPARSEMEM
 | 
						|
static inline void page_ext_init_flatmem(void)
 | 
						|
{
 | 
						|
}
 | 
						|
extern void page_ext_init(void);
 | 
						|
#else
 | 
						|
extern void page_ext_init_flatmem(void);
 | 
						|
static inline void page_ext_init(void)
 | 
						|
{
 | 
						|
}
 | 
						|
#endif
 | 
						|
 | 
						|
struct page_ext *lookup_page_ext(struct page *page);
 | 
						|
 | 
						|
#else /* !CONFIG_PAGE_EXTENSION */
 | 
						|
struct page_ext;
 | 
						|
 | 
						|
static inline void pgdat_page_ext_init(struct pglist_data *pgdat)
 | 
						|
{
 | 
						|
}
 | 
						|
 | 
						|
static inline struct page_ext *lookup_page_ext(struct page *page)
 | 
						|
{
 | 
						|
	return NULL;
 | 
						|
}
 | 
						|
 | 
						|
static inline void page_ext_init(void)
 | 
						|
{
 | 
						|
}
 | 
						|
 | 
						|
static inline void page_ext_init_flatmem(void)
 | 
						|
{
 | 
						|
}
 | 
						|
#endif /* CONFIG_PAGE_EXTENSION */
 | 
						|
#endif /* __LINUX_PAGE_EXT_H */
 |