mm:add KPF_ZERO_PAGE flag for /proc/kpageflags

Add KPF_ZERO_PAGE flag for zero_page, so that userspace processes can
detect zero_page in /proc/kpageflags, and then do memory analysis more
accurately.

Signed-off-by: Yalin Wang <yalin.wang@sonymobile.com>
Acked-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Wang, Yalin 2015-02-11 15:24:51 -08:00 committed by Linus Torvalds
parent 1d148e218a
commit 56873f43ab
6 changed files with 36 additions and 9 deletions

View file

@ -157,6 +157,13 @@ static inline int hpage_nr_pages(struct page *page)
extern int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, pmd_t pmd, pmd_t *pmdp);
extern struct page *huge_zero_page;
static inline bool is_huge_zero_page(struct page *page)
{
return ACCESS_ONCE(huge_zero_page) == page;
}
#else /* CONFIG_TRANSPARENT_HUGEPAGE */
#define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
#define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
@ -206,6 +213,11 @@ static inline int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_str
return 0;
}
static inline bool is_huge_zero_page(struct page *page)
{
return false;
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
#endif /* _LINUX_HUGE_MM_H */