void step2_gpu(int *n) {
int nprocs, procid;
MPI_Comm_rank(MPI_COMM_WORLD, &procid);
MPI_Comm_size(MPI_COMM_WORLD, &nprocs);
/* Create Cartesian Communicator */
int c_dims[2];
MPI_Comm c_comm;
accfft_create_comm(MPI_COMM_WORLD, c_dims, &c_comm);
float *data, *data_cpu;
Complexf *data_hat;
double f_time = 0 * MPI_Wtime(), i_time = 0, setup_time = 0;
int alloc_max = 0;
int isize[3], osize[3], istart[3], ostart[3];
/* Get the local pencil size and the allocation size */
alloc_max = accfft_local_size_dft_r2c_gpuf(n, isize, istart, osize, ostart,
c_comm);
/* Note that both need to be allocated by alloc_max because of inplace transform*/
data_cpu = (float*) malloc(alloc_max);
cudaMalloc((void**) &data, alloc_max);
//accfft_init(nthreads);
/* Create FFT plan */
setup_time = -MPI_Wtime();
accfft_plan_gpuf * plan = accfft_plan_dft_3d_r2c_gpuf(n, data, data, c_comm,
ACCFFT_MEASURE);
setup_time += MPI_Wtime();
/* Warm Up */
accfft_execute_r2c_gpuf(plan, data, (Complexf*) data);
accfft_execute_r2c_gpuf(plan, data, (Complexf*) data);
/* Initialize data */
initialize_gpu(data, n, isize, istart);
MPI_Barrier(c_comm);
/* Perform forward FFT */
f_time -= MPI_Wtime();
accfft_execute_r2c_gpuf(plan, data, (Complexf*) data);
f_time += MPI_Wtime();
MPI_Barrier(c_comm);
/* Perform backward FFT */
i_time -= MPI_Wtime();
accfft_execute_c2r_gpuf(plan, (Complexf*) data, data);
i_time += MPI_Wtime();
/* copy back results on CPU */
cudaMemcpy(data_cpu, data, alloc_max, cudaMemcpyDeviceToHost);
/* Check Error */
check_err(data_cpu, n, c_comm);
/* Compute some timings statistics */
double g_f_time, g_i_time, g_setup_time;
MPI_Reduce(&f_time, &g_f_time, 1, MPI_DOUBLE, MPI_MAX, 0, MPI_COMM_WORLD);
MPI_Reduce(&i_time, &g_i_time, 1, MPI_DOUBLE, MPI_MAX, 0, MPI_COMM_WORLD);
MPI_Reduce(&setup_time, &g_setup_time, 1, MPI_DOUBLE, MPI_MAX, 0,
MPI_COMM_WORLD);
PCOUT << "GPU Timing for FFT of size " << n[0] << "*" << n[1] << "*" << n[2]
<< std::endl;
PCOUT << "Setup \t" << g_setup_time << std::endl;
PCOUT << "FFT \t" << g_f_time << std::endl;
PCOUT << "IFFT \t" << g_i_time << std::endl;
free(data_cpu);
cudaFree(data);
accfft_destroy_plan_gpu(plan);
accfft_cleanup_gpuf();
MPI_Comm_free(&c_comm);
return;
} // end step2_gpu
void accfft_execute_c2r_gpu_t(accfft_plan_gpuf* plan, Tc* data,T* data_out, double * timer,std::bitset<3> XYZ){
accfft_execute_c2r_gpuf(plan,data,data_out,timer,XYZ);
return;
}