From ca12b7c48942d21b2e7890b820db9d578bc291cd Mon Sep 17 00:00:00 2001 From: Tao Ma Date: Mon, 18 Aug 2008 17:38:52 +0800 Subject: [PATCH] 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 Signed-off-by: Mark Fasheh --- fs/ocfs2/alloc.c | 39 ++++++++++++++++++++++++++++++--------- fs/ocfs2/alloc.h | 5 +++++ 2 files changed, 35 insertions(+), 9 deletions(-) diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c index 06ea7913c134..f65cb43edb7c 100644 --- a/fs/ocfs2/alloc.c +++ b/fs/ocfs2/alloc.c @@ -79,6 +79,7 @@ struct ocfs2_extent_tree { 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_operations ocfs2_xattr_tree_et_ops = { }; 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 @@ static struct ocfs2_extent_tree* (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 @@ out: 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 @@ static void ocfs2_figure_contig_type(struct inode *inode, } } 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 @@ static int ocfs2_figure_insert_type(struct inode *inode, 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 @@ static int ocfs2_figure_insert_type(struct inode *inode, * 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 ocfs2_dinode_insert_extent(struct ocfs2_super *osb, 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 ocfs2_xattr_value_insert_extent(struct ocfs2_super *osb, 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 ocfs2_xattr_tree_insert_extent(struct ocfs2_super *osb, 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 @@ int ocfs2_mark_extent_written(struct inode *inode, struct buffer_head *root_bh, 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 @@ int ocfs2_remove_extent(struct inode *inode, struct buffer_head *root_bh, 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); diff --git a/fs/ocfs2/alloc.h b/fs/ocfs2/alloc.h index cd4e12d2b6b9..23c695ddaa52 100644 --- a/fs/ocfs2/alloc.h +++ b/fs/ocfs2/alloc.h @@ -32,6 +32,11 @@ enum ocfs2_extent_tree_type { OCFS2_XATTR_TREE_EXTENT, }; +/* + * For xattr tree leaf, we limit the leaf byte size to be 64K. + */ +#define OCFS2_MAX_XATTR_TREE_LEAF_SIZE 65536 + struct ocfs2_alloc_context; int ocfs2_dinode_insert_extent(struct ocfs2_super *osb, handle_t *handle, -- 2.20.1