aboutsummaryrefslogtreecommitdiffstats
path: root/fs/btrfs/extent_io.h
diff options
context:
space:
mode:
authorrichard kennedy <richard@rsk.demon.co.uk>2011-06-07 10:46:32 +0000
committerChris Mason <chris.mason@oracle.com>2011-06-10 18:57:10 -0400
commit9eb9104c665aae2401a1723c044669eb10240072 (patch)
tree21b3395270516a4978b10090fe8d9bd4bce8203b /fs/btrfs/extent_io.h
parent38e880540f983045da7a00fbc50daad238207fc5 (diff)
btrfs: remove 64bit alignment padding to allow extent_buffer to fit into one fewer cacheline
Reorder extent_buffer to remove 8 bytes of alignment padding on 64 bit builds. This shrinks its size to 128 bytes allowing it to fit into one fewer cache lines and allows more objects per slab in its kmem_cache. slabinfo extent_buffer reports :- before:- Sizes (bytes) Slabs ---------------------------------- Object : 136 Total : 123 SlabObj: 136 Full : 121 SlabSiz: 4096 Partial: 0 Loss : 0 CpuSlab: 2 Align : 8 Objects: 30 after :- Object : 128 Total : 4 SlabObj: 128 Full : 2 SlabSiz: 4096 Partial: 0 Loss : 0 CpuSlab: 2 Align : 8 Objects: 32 Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk> Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs/extent_io.h')
-rw-r--r--fs/btrfs/extent_io.h2
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 4e8445a4757..a11a92ee2d3 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -126,9 +126,9 @@ struct extent_buffer {
unsigned long map_len;
struct page *first_page;
unsigned long bflags;
- atomic_t refs;
struct list_head leak_list;
struct rcu_head rcu_head;
+ atomic_t refs;
/* the spinlock is used to protect most operations */
spinlock_t lock;