diff options
| author | Rafael Aquini <aquini@redhat.com> | 2012-12-12 04:02:38 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-12 05:22:26 +0400 |
| commit | 18468d93e53b037e1a04ec58398eab763d054064 (patch) | |
| tree | 74392b876400391567f55bb5292107b65e3791a2 /include/linux/pagemap.h | |
| parent | 252aa6f5be64c90c67b9f066ccff880f6b487d32 (diff) | |
| download | linux-18468d93e53b037e1a04ec58398eab763d054064.tar.xz | |
mm: introduce a common interface for balloon pages mobility
Memory fragmentation introduced by ballooning might reduce significantly
the number of 2MB contiguous memory blocks that can be used within a guest,
thus imposing performance penalties associated with the reduced number of
transparent huge pages that could be used by the guest workload.
This patch introduces a common interface to help a balloon driver on
making its page set movable to compaction, and thus allowing the system
to better leverage the compation efforts on memory defragmentation.
[akpm@linux-foundation.org: use PAGE_FLAGS_CHECK_AT_PREP, s/__balloon_page_flags/page_flags_cleared/, small cleanups]
[rientjes@google.com: allow balloon compaction for any system with memory compaction enabled, which is the defconfig]
Signed-off-by: Rafael Aquini <aquini@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/pagemap.h')
| -rw-r--r-- | include/linux/pagemap.h | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index e42c762f0dc7..6da609d14c15 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -24,6 +24,7 @@ enum mapping_flags { AS_ENOSPC = __GFP_BITS_SHIFT + 1, /* ENOSPC on async write */ AS_MM_ALL_LOCKS = __GFP_BITS_SHIFT + 2, /* under mm_take_all_locks() */ AS_UNEVICTABLE = __GFP_BITS_SHIFT + 3, /* e.g., ramdisk, SHM_LOCK */ + AS_BALLOON_MAP = __GFP_BITS_SHIFT + 4, /* balloon page special map */ }; static inline void mapping_set_error(struct address_space *mapping, int error) @@ -53,6 +54,21 @@ static inline int mapping_unevictable(struct address_space *mapping) return !!mapping; } +static inline void mapping_set_balloon(struct address_space *mapping) +{ + set_bit(AS_BALLOON_MAP, &mapping->flags); +} + +static inline void mapping_clear_balloon(struct address_space *mapping) +{ + clear_bit(AS_BALLOON_MAP, &mapping->flags); +} + +static inline int mapping_balloon(struct address_space *mapping) +{ + return mapping && test_bit(AS_BALLOON_MAP, &mapping->flags); +} + static inline gfp_t mapping_gfp_mask(struct address_space * mapping) { return (__force gfp_t)mapping->flags & __GFP_BITS_MASK; |