smpi_group_index(smpi_comm_group(win->comm),target_rank), SMPI_RMA_TAG+1, recv_win->comm, MPI_OP_NULL);
//push request to receiver's win
smpi_group_index(smpi_comm_group(win->comm),target_rank), SMPI_RMA_TAG+1, recv_win->comm, MPI_OP_NULL);
//push request to receiver's win