Btrfs: directory readahead
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 7ecbe7c..a29a781b 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -585,6 +585,31 @@
return d_splice_alias(inode, dentry);
}
+static void reada_leaves(struct btrfs_root *root, struct btrfs_path *path)
+{
+ struct btrfs_node *node;
+ int i;
+ int nritems;
+ u64 objectid;
+ u64 item_objectid;
+ u64 blocknr;
+ int slot;
+
+ if (!path->nodes[1])
+ return;
+ node = btrfs_buffer_node(path->nodes[1]);
+ slot = path->slots[1];
+ objectid = btrfs_disk_key_objectid(&node->ptrs[slot].key);
+ nritems = btrfs_header_nritems(&node->header);
+ for (i = slot; i < nritems; i++) {
+ item_objectid = btrfs_disk_key_objectid(&node->ptrs[i].key);
+ if (item_objectid != objectid)
+ break;
+ blocknr = btrfs_node_blockptr(node, i);
+ readahead_tree_block(root, blocknr);
+ }
+}
+
static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
struct inode *inode = filp->f_path.dentry->d_inode;
@@ -619,6 +644,7 @@
if (ret < 0)
goto err;
advance = 0;
+ reada_leaves(root, path);
while(1) {
leaf = btrfs_buffer_leaf(path->nodes[0]);
nritems = btrfs_header_nritems(&leaf->header);
@@ -631,6 +657,8 @@
leaf = btrfs_buffer_leaf(path->nodes[0]);
nritems = btrfs_header_nritems(&leaf->header);
slot = path->slots[0];
+ if (path->slots[1] == 0)
+ reada_leaves(root, path);
} else {
slot++;
path->slots[0]++;