Btrfs: Defrag only leaves, and only when the parent node has a single objectid

This allows us to defrag huge directories, but skip the expensive defrag
case in more common usage, where it does not help as much.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 5 insertions, 31 deletions

diff --git a/fs/btrfs/tree-defrag.c b/fs/btrfs/tree-defrag.c
index f86eccf511b9..b02355a7b143 100644
--- a/fs/btrfs/tree-defrag.c
+++ b/fs/btrfs/tree-defrag.c
@@ -76,7 +76,9 @@ static int defrag_walk_down(struct btrfs_trans_handle *trans,
                 if (*level == 1) {
                         ret = btrfs_realloc_node(trans, root,
                                                  path->nodes[*level],
-                                                 cache_only, last_ret);
+                                                 path->slots[*level],
+                                                 cache_only, last_ret,
+                                                 &root->defrag_progress);
                         if (is_extent)
                                 btrfs_extent_post_op(trans, root);
 
@@ -100,10 +102,6 @@ static int defrag_walk_down(struct btrfs_trans_handle *trans,
                 ret = btrfs_cow_block(trans, root, next, path->nodes[*level],
                                       path->slots[*level], &next);
                 BUG_ON(ret);
-                ret = btrfs_realloc_node(trans, root, next, cache_only,
-                                         last_ret);
-                BUG_ON(ret);
-
                 if (is_extent)
                         btrfs_extent_post_op(trans, root);
 
@@ -122,8 +120,8 @@ static int defrag_walk_down(struct btrfs_trans_handle *trans,
         free_extent_buffer(path->nodes[*level]);
         path->nodes[*level] = NULL;
         *level += 1;
-        WARN_ON(ret);
-        return 0;
+        WARN_ON(ret && ret != -EAGAIN);
+        return ret;
 }
 
 static int defrag_walk_up(struct btrfs_trans_handle *trans,
@@ -147,27 +145,6 @@ static int defrag_walk_up(struct btrfs_trans_handle *trans,
                         root->defrag_level = i;
                         return 0;
                 } else {
-                        if (*level > 1 && path->nodes[*level] != root->node &&
-                            btrfs_buffer_defrag(path->nodes[*level])) {
-                                struct extent_buffer *next;
-                                u64 last;
-                                int ret;
-                                ret = btrfs_cow_block(trans, root,
-                                                      path->nodes[*level],
-                                                      path->nodes[*level + 1],
-                                                      path->slots[*level + 1],
-                                                      &next);
-                                BUG_ON(ret);
-                                path->nodes[*level] = next;
-                                last = next->start;
-                                ret = btrfs_realloc_node(trans, root, next,
-                                                         cache_only, &last);
-                                BUG_ON(ret);
-
-                                if (root == root->fs_info->extent_root)
-                                        btrfs_extent_post_op(trans, root);
-                        }
-
                         btrfs_clear_buffer_defrag(path->nodes[*level]);
                         free_extent_buffer(path->nodes[*level]);
                         path->nodes[*level] = NULL;
@@ -211,9 +188,6 @@ int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
                 extent_buffer_get(root->node);
                 ret = btrfs_cow_block(trans, root, root->node, NULL, 0, &tmp);
                 BUG_ON(ret);
-                ret = btrfs_realloc_node(trans, root, root->node, cache_only,
-                                         &last_ret);
-                BUG_ON(ret);
                 path->nodes[level] = root->node;
                 path->slots[level] = 0;
                 if (is_extent)