ocfs2: Optionally limit extent size in ocfs2_insert_extent()
In xattr bucket, we want to limit the maximum size of a btree leaf,
otherwise we'll lose the benefits of hashing because we'll have to search
large leaves.
So add a new field in ocfs2_extent_tree which indicates the maximum leaf cluster
size we want so that we can prevent ocfs2_insert_extent() from merging the leaf
record even if it is contiguous with an adjacent record.
Other btree types are not affected by this change.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 06ea791..f65cb43 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -79,6 +79,7 @@
struct buffer_head *root_bh;
struct ocfs2_extent_list *root_el;
void *private;
+ unsigned int max_leaf_clusters;
};
static void ocfs2_dinode_set_last_eb_blk(struct ocfs2_extent_tree *et,
@@ -220,7 +221,8 @@
};
static struct ocfs2_extent_tree*
- ocfs2_new_extent_tree(struct buffer_head *bh,
+ ocfs2_new_extent_tree(struct inode *inode,
+ struct buffer_head *bh,
enum ocfs2_extent_tree_type et_type,
void *private)
{
@@ -248,6 +250,8 @@
(struct ocfs2_xattr_block *)bh->b_data;
et->root_el = &xb->xb_attrs.xb_root.xt_list;
et->eops = &ocfs2_xattr_tree_et_ops;
+ et->max_leaf_clusters = ocfs2_clusters_for_bytes(inode->i_sb,
+ OCFS2_MAX_XATTR_TREE_LEAF_SIZE);
}
return et;
@@ -4109,7 +4113,8 @@
static void ocfs2_figure_contig_type(struct inode *inode,
struct ocfs2_insert_type *insert,
struct ocfs2_extent_list *el,
- struct ocfs2_extent_rec *insert_rec)
+ struct ocfs2_extent_rec *insert_rec,
+ struct ocfs2_extent_tree *et)
{
int i;
enum ocfs2_contig_type contig_type = CONTIG_NONE;
@@ -4125,6 +4130,20 @@
}
}
insert->ins_contig = contig_type;
+
+ if (insert->ins_contig != CONTIG_NONE) {
+ struct ocfs2_extent_rec *rec =
+ &el->l_recs[insert->ins_contig_index];
+ unsigned int len = le16_to_cpu(rec->e_leaf_clusters) +
+ le16_to_cpu(insert_rec->e_leaf_clusters);
+
+ /*
+ * Caller might want us to limit the size of extents, don't
+ * calculate contiguousness if we might exceed that limit.
+ */
+ if (et->max_leaf_clusters && len > et->max_leaf_clusters)
+ insert->ins_contig = CONTIG_NONE;
+ }
}
/*
@@ -4232,7 +4251,7 @@
le16_to_cpu(el->l_next_free_rec);
if (!insert->ins_tree_depth) {
- ocfs2_figure_contig_type(inode, insert, el, insert_rec);
+ ocfs2_figure_contig_type(inode, insert, el, insert_rec, et);
ocfs2_figure_appending_type(insert, el, insert_rec);
return 0;
}
@@ -4266,7 +4285,7 @@
* into two types of appends: simple record append, or a
* rotate inside the tail leaf.
*/
- ocfs2_figure_contig_type(inode, insert, el, insert_rec);
+ ocfs2_figure_contig_type(inode, insert, el, insert_rec, et);
/*
* The insert code isn't quite ready to deal with all cases of
@@ -4402,7 +4421,7 @@
int status;
struct ocfs2_extent_tree *et = NULL;
- et = ocfs2_new_extent_tree(root_bh, OCFS2_DINODE_EXTENT, NULL);
+ et = ocfs2_new_extent_tree(inode, root_bh, OCFS2_DINODE_EXTENT, NULL);
if (!et) {
status = -ENOMEM;
mlog_errno(status);
@@ -4433,7 +4452,8 @@
int status;
struct ocfs2_extent_tree *et = NULL;
- et = ocfs2_new_extent_tree(root_bh, OCFS2_XATTR_VALUE_EXTENT, private);
+ et = ocfs2_new_extent_tree(inode, root_bh,
+ OCFS2_XATTR_VALUE_EXTENT, private);
if (!et) {
status = -ENOMEM;
mlog_errno(status);
@@ -4463,7 +4483,8 @@
int status;
struct ocfs2_extent_tree *et = NULL;
- et = ocfs2_new_extent_tree(root_bh, OCFS2_XATTR_TREE_EXTENT, NULL);
+ et = ocfs2_new_extent_tree(inode, root_bh, OCFS2_XATTR_TREE_EXTENT,
+ NULL);
if (!et) {
status = -ENOMEM;
mlog_errno(status);
@@ -4879,7 +4900,7 @@
goto out;
}
- et = ocfs2_new_extent_tree(root_bh, et_type, private);
+ et = ocfs2_new_extent_tree(inode, root_bh, et_type, private);
if (!et) {
ret = -ENOMEM;
mlog_errno(ret);
@@ -5177,7 +5198,7 @@
struct ocfs2_path *path = NULL;
struct ocfs2_extent_tree *et = NULL;
- et = ocfs2_new_extent_tree(root_bh, et_type, private);
+ et = ocfs2_new_extent_tree(inode, root_bh, et_type, private);
if (!et) {
ret = -ENOMEM;
mlog_errno(ret);