btrfs: qgroup: Add new trace point for qgroup data reserve

Now each qgroup reserve for data will has its ftrace event for better
debugging.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/fs/btrfs/qgroup.h b/fs/btrfs/qgroup.h
index adb03da..686b60f 100644
--- a/fs/btrfs/qgroup.h
+++ b/fs/btrfs/qgroup.h
@@ -33,6 +33,13 @@
 	struct ulist *old_roots;
 };
 
+/*
+ * For qgroup event trace points only
+ */
+#define QGROUP_RESERVE		(1<<0)
+#define QGROUP_RELEASE		(1<<1)
+#define QGROUP_FREE		(1<<2)
+
 int btrfs_quota_enable(struct btrfs_trans_handle *trans,
 		       struct btrfs_fs_info *fs_info);
 int btrfs_quota_disable(struct btrfs_trans_handle *trans,
@@ -81,6 +88,7 @@
 						 u64 ref_root, u64 num_bytes)
 {
 	btrfs_qgroup_free_refroot(fs_info, ref_root, num_bytes);
+	trace_btrfs_qgroup_free_delayed_ref(ref_root, num_bytes);
 }
 void assert_qgroups_uptodate(struct btrfs_trans_handle *trans);