linux_dsm_epyc7002/include/linux/page_ext.h
Vlastimil Babka 37389167a2 mm, page_owner: keep owner info when freeing the page
For debugging purposes it might be useful to keep the owner info even
after page has been freed, and include it in e.g.  dump_page() when
detecting a bad page state.  For that, change the PAGE_EXT_OWNER flag
meaning to "page owner info has been set at least once" and add new
PAGE_EXT_OWNER_ACTIVE for tracking whether page is supposed to be
currently tracked allocated or free.  Adjust dump_page() accordingly,
distinguishing free and allocated pages.  In the page_owner debugfs file,
keep printing only allocated pages so that existing scripts are not
confused, and also because free pages are irrelevant for the memory
statistics or leak detection that's the typical use case of the file,
anyway.

Link: http://lkml.kernel.org/r/20190820131828.22684-4-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-24 15:54:08 -07:00

76 lines
1.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#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
enum page_ext_flags {
PAGE_EXT_OWNER,
PAGE_EXT_OWNER_ACTIVE,
#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(const 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(const 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 */