fix bug in calling master for spawn instead of the parent thread
fix bug in calling master for spawn instead of the parent thread

buaasun/grappa,alexfrolov/grappa,alexfrolov/grappa,uwsampa/grappa,uwsampa/grappa,uwsampa/grappa,alexfrolov/grappa,uwsampa/grappa,buaasun/grappa,buaasun/grappa,buaasun/grappa,alexfrolov/grappa,buaasun/grappa,alexfrolov/grappa,alexfrolov/grappa,uwsampa/grappa,uwsampa/grappa,uwsampa/grappa,alexfrolov/grappa,buaasun/grappa,buaasun/grappa