diff options
| author | Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> | 2016-03-17 14:17:41 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-03-17 15:09:34 -0700 |
| commit | 832fc1de01aea28255cb11d270679b7f1273f0d7 (patch) | |
| tree | ef020cb2a44d1fee4df1359fbb3fc11a08de733b | |
| parent | 12580e4b54ba8a1b22ec977c200be0174ca42348 (diff) | |
/proc/kpageflags: return KPF_BUDDY for "tail" buddy pages
Currently /proc/kpageflags returns nothing for "tail" buddy pages, which
is inconvenient when grasping how free pages are distributed. This
patch sets KPF_BUDDY for such pages.
With this patch:
$ grep MemFree /proc/meminfo ; tools/vm/page-types -b buddy
MemFree: 3134992 kB
flags page-count MB symbolic-flags long-symbolic-flags
0x0000000000000400 779272 3044 __________B_______________________________ buddy
0x0000000000000c00 4385 17 __________BM______________________________ buddy,mmap
total 783657 3061
783657 pages is 3134628 kB (roughly consistent with the global counter,)
so it's OK.
[akpm@linux-foundation.org: update comment, per Naoya]
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>>
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>
| -rw-r--r-- | fs/proc/page.c | 6 | ||||
| -rw-r--r-- | include/linux/page-flags.h | 2 | ||||
| -rw-r--r-- | mm/internal.h | 3 | ||||
| -rw-r--r-- | mm/page_alloc.c | 2 |
4 files changed, 6 insertions, 7 deletions
diff --git a/fs/proc/page.c b/fs/proc/page.c index b2855eea5405..0be626d85331 100644 --- a/fs/proc/page.c +++ b/fs/proc/page.c @@ -103,9 +103,9 @@ u64 stable_page_flags(struct page *page) * pseudo flags for the well known (anonymous) memory mapped pages * * Note that page->_mapcount is overloaded in SLOB/SLUB/SLQB, so the - * simple test in page_mapcount() is not enough. + * simple test in page_mapped() is not enough. */ - if (!PageSlab(page) && page_mapcount(page)) + if (!PageSlab(page) && page_mapped(page)) u |= 1 << KPF_MMAP; if (PageAnon(page)) u |= 1 << KPF_ANON; @@ -148,6 +148,8 @@ u64 stable_page_flags(struct page *page) */ if (PageBuddy(page)) u |= 1 << KPF_BUDDY; + else if (page_count(page) == 0 && is_free_buddy_page(page)) + u |= 1 << KPF_BUDDY; if (PageBalloon(page)) u |= 1 << KPF_BALLOON; diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 19724e6ebd26..597695523679 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -593,6 +593,8 @@ static inline void __ClearPageBuddy(struct page *page) atomic_set(&page->_mapcount, -1); } +extern bool is_free_buddy_page(struct page *page); + #define PAGE_BALLOON_MAPCOUNT_VALUE (-256) static inline int PageBalloon(struct page *page) diff --git a/mm/internal.h b/mm/internal.h index ad9400d759c8..b95952c2faec 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -148,9 +148,6 @@ extern int __isolate_free_page(struct page *page, unsigned int order); extern void __free_pages_bootmem(struct page *page, unsigned long pfn, unsigned int order); extern void prep_compound_page(struct page *page, unsigned int order); -#ifdef CONFIG_MEMORY_FAILURE -extern bool is_free_buddy_page(struct page *page); -#endif extern int user_min_free_kbytes; #if defined CONFIG_COMPACTION || defined CONFIG_CMA diff --git a/mm/page_alloc.c b/mm/page_alloc.c index c46b75d14b6f..c7332a4bc8db 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -7152,7 +7152,6 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) } #endif -#ifdef CONFIG_MEMORY_FAILURE bool is_free_buddy_page(struct page *page) { struct zone *zone = page_zone(page); @@ -7171,4 +7170,3 @@ bool is_free_buddy_page(struct page *page) return order < MAX_ORDER; } -#endif |