add locking convention

src/datawizard/data_request.c

@@ -108,7 +108,7 @@ starpu_data_request_t _starpu_create_data_request(starpu_data_handle handle, uin
 	return r;
 }
 
-/* handle->lock should be taken */
+/* handle->lock should be taken. r is returned locked */
 starpu_data_request_t _starpu_search_existing_data_request(starpu_data_handle handle, uint32_t dst_node, starpu_access_mode mode)
 {
 	starpu_data_request_t r = handle->per_node[dst_node].request;