diff options
| author | Nicholas Piggin <npiggin@gmail.com> | 2016-12-25 13:00:29 +1000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-25 11:54:48 -0800 |
| commit | 6326fec1122cde256bd2a8c63f2606e08e44ce1d (patch) | |
| tree | 5e5bc0e4c71903bbdc6477f4868d35f970743e21 /mm/migrate.c | |
| parent | 7c0f6ba682b9c7632072ffbedf8d328c8f3c42ba (diff) | |
mm: Use owner_priv bit for PageSwapCache, valid when PageSwapBacked
A page is not added to the swap cache without being swap backed,
so PageSwapBacked mappings can use PG_owner_priv_1 for PageSwapCache.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Bob Peterson <rpeterso@redhat.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Andrew Lutomirski <luto@kernel.org>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/migrate.c')
| -rw-r--r-- | mm/migrate.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/mm/migrate.c b/mm/migrate.c index 0ed24b1fa77b..87f4d0f81819 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -466,13 +466,15 @@ int migrate_page_move_mapping(struct address_space *mapping, */ newpage->index = page->index; newpage->mapping = page->mapping; - if (PageSwapBacked(page)) - __SetPageSwapBacked(newpage); - get_page(newpage); /* add cache reference */ - if (PageSwapCache(page)) { - SetPageSwapCache(newpage); - set_page_private(newpage, page_private(page)); + if (PageSwapBacked(page)) { + __SetPageSwapBacked(newpage); + if (PageSwapCache(page)) { + SetPageSwapCache(newpage); + set_page_private(newpage, page_private(page)); + } + } else { + VM_BUG_ON_PAGE(PageSwapCache(page), page); } /* Move dirty while page refs frozen and newpage not yet exposed */ |