diff options
author | Vladimir Davydov <vdavydov@virtuozzo.com> | 2016-07-26 15:24:18 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-26 16:19:19 -0700 |
commit | 632c0a1affd861f81abdd136c886418571e19a51 (patch) | |
tree | 583d947ff0c673e009487666e730bf854195ca4a /include/linux/mm_types.h | |
parent | 99691addb42919251dcc082a70b7a11733dfcbcc (diff) |
mm: clean up non-standard page->_mapcount users
- Add a proper comment to page->_mapcount.
- Introduce a macro for generating helper functions.
- Place all special page->_mapcount values next to each other so that
readers can see all possible values and so we don't get duplicates.
Link: http://lkml.kernel.org/r/502f49000e0b63e6c62e338fac6b420bf34fb526.1464079537.git.vdavydov@virtuozzo.com
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/mm_types.h')
-rw-r--r-- | include/linux/mm_types.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index a50ad735d518..79472b22d23f 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -85,6 +85,11 @@ struct page { /* * Count of ptes mapped in mms, to show when * page is mapped & limit reverse map searches. + * + * Extra information about page type may be + * stored here for pages that are never mapped, + * in which case the value MUST BE <= -2. + * See page-flags.h for more details. */ atomic_t _mapcount; |