MPI_Request rreq = smpi_rma_recv_init(recv_addr, target_count, target_datatype,
smpi_process_index(), smpi_group_index(smpi_comm_group(win->comm),target_rank), RMA_TAG+3, recv_win->comm, op);
//push request to receiver's win
MPI_Request rreq = smpi_rma_recv_init(recv_addr, target_count, target_datatype,
smpi_process_index(), smpi_group_index(smpi_comm_group(win->comm),target_rank), RMA_TAG+3, recv_win->comm, op);
//push request to receiver's win