Btrfs: don't cache the csum value into the extent state tree

Before applying this patch, we cached the csum value into the extent state
tree when reading some data from the disk, this operation increased the lock
contention of the state tree.

Now, we just store the csum value into the bio structure or other unshared
structure, so we can reduce the lock contention.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 4 insertions, 6 deletions

diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 3b8c4e26e1da..f7544afefdb9 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -62,6 +62,7 @@
 
 struct extent_state;
 struct btrfs_root;
+struct btrfs_io_bio;
 
 typedef int (extent_submit_bio_hook_t)(struct inode *inode, int rw,
                                        struct bio *bio, int mirror_num,
@@ -77,8 +78,9 @@ struct extent_io_ops {
                               size_t size, struct bio *bio,
                               unsigned long bio_flags);
         int (*readpage_io_failed_hook)(struct page *page, int failed_mirror);
-        int (*readpage_end_io_hook)(struct page *page, u64 start, u64 end,
-                                    struct extent_state *state, int mirror);
+        int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset,
+                                    struct page *page, u64 start, u64 end,
+                                    int mirror);
         int (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
                                       struct extent_state *state, int uptodate);
         void (*set_bit_hook)(struct inode *inode, struct extent_state *state,
@@ -262,10 +264,6 @@ int extent_readpages(struct extent_io_tree *tree,
 int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
                 __u64 start, __u64 len, get_extent_t *get_extent);
 int set_state_private(struct extent_io_tree *tree, u64 start, u64 private);
-void extent_cache_csums_dio(struct extent_io_tree *tree, u64 start, u32 csums[],
-                            int count);
-void extent_cache_csums(struct extent_io_tree *tree, struct bio *bio,
-                        int bvec_index, u32 csums[], int count);
 int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private);
 void set_page_extent_mapped(struct page *page);