btrfs: use rb_find_add() in add_qgroup_rb()

Use the rb-tree helper so we don't open code the search and insert
code.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Pan Chuang <panchuang@vivo.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 2e2a76c3e92a9c3781681fbf828c1fde8b3f5246..694df7f64f94b56ce5dcde9415fd5d343c588302 100644 (file)
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -183,6 +183,13 @@ static struct btrfs_qgroup *find_qgroup_rb(const struct btrfs_fs_info *fs_info,
        return rb_entry_safe(node, struct btrfs_qgroup, node);
 }
 
+static int btrfs_qgroup_qgroupid_cmp(struct rb_node *new, const struct rb_node *existing)
+{
+       const struct btrfs_qgroup *new_qgroup = rb_entry(new, struct btrfs_qgroup, node);
+
+       return btrfs_qgroup_qgroupid_key_cmp(&new_qgroup->qgroupid, existing);
+}
+
 /*
  * Add qgroup to the filesystem's qgroup tree.
  *
@@ -195,39 +202,25 @@ static struct btrfs_qgroup *add_qgroup_rb(struct btrfs_fs_info *fs_info,
                                          struct btrfs_qgroup *prealloc,
                                          u64 qgroupid)
 {
-       struct rb_node **p = &fs_info->qgroup_tree.rb_node;
-       struct rb_node *parent = NULL;
-       struct btrfs_qgroup *qgroup;
+       struct rb_node *node;
 
        /* Caller must have pre-allocated @prealloc. */
        ASSERT(prealloc);
 
-       while (*p) {
-               parent = *p;
-               qgroup = rb_entry(parent, struct btrfs_qgroup, node);
-
-               if (qgroup->qgroupid < qgroupid) {
-                       p = &(*p)->rb_left;
-               } else if (qgroup->qgroupid > qgroupid) {
-                       p = &(*p)->rb_right;
-               } else {
-                       kfree(prealloc);
-                       return qgroup;
-               }
+       prealloc->qgroupid = qgroupid;
+       node = rb_find_add(&prealloc->node, &fs_info->qgroup_tree, btrfs_qgroup_qgroupid_cmp);
+       if (node) {
+               kfree(prealloc);
+               return rb_entry(node, struct btrfs_qgroup, node);
        }
 
-       qgroup = prealloc;
-       qgroup->qgroupid = qgroupid;
-       INIT_LIST_HEAD(&qgroup->groups);
-       INIT_LIST_HEAD(&qgroup->members);
-       INIT_LIST_HEAD(&qgroup->dirty);
-       INIT_LIST_HEAD(&qgroup->iterator);
-       INIT_LIST_HEAD(&qgroup->nested_iterator);
-
-       rb_link_node(&qgroup->node, parent, p);
-       rb_insert_color(&qgroup->node, &fs_info->qgroup_tree);
+       INIT_LIST_HEAD(&prealloc->groups);
+       INIT_LIST_HEAD(&prealloc->members);
+       INIT_LIST_HEAD(&prealloc->dirty);
+       INIT_LIST_HEAD(&prealloc->iterator);
+       INIT_LIST_HEAD(&prealloc->nested_iterator);
 
-       return qgroup;
+       return prealloc;
 }
 
 static void __del_qgroup_rb(struct btrfs_qgroup *qgroup)