+ /*
+ * The metadata channel might not be present.
+ *
+ * Consumer stream allocation can be done
+ * asynchronously and can fail on intermediary
+ * operations (i.e add context) and lead to data
+ * channels created with no metadata channel.
+ */
+ if (!reg->registry->reg.ust->metadata_key) {
+ /* Skip since no metadata is present. */
+ continue;
+ }
+