void step1_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] = { 0 };
MPI_Comm c_comm;
accfft_create_comm(MPI_COMM_WORLD, c_dims, &c_comm);
double *data, *data_cpu;
Complex *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_gpu(n, isize, istart, osize, ostart,
c_comm);
data_cpu = (double*) malloc(
isize[0] * isize[1] * isize[2] * sizeof(double));
//data_hat=(Complex*)accfft_alloc(alloc_max);
cudaMalloc((void**) &data, isize[0] * isize[1] * isize[2] * sizeof(double));
cudaMalloc((void**) &data_hat, alloc_max);
//accfft_init(nthreads);
/* Create FFT plan */
setup_time = -MPI_Wtime();
accfft_plan_gpu * plan = accfft_plan_dft_3d_r2c_gpu(n, data,
(double*) data_hat, c_comm, ACCFFT_MEASURE);
setup_time += MPI_Wtime();
/* Warm Up */
accfft_execute_r2c_gpu(plan, data, data_hat);
accfft_execute_r2c_gpu(plan, data, data_hat);
/* Initialize data */
initialize(data_cpu, n, c_comm);
cudaMemcpy(data, data_cpu, isize[0] * isize[1] * isize[2] * sizeof(double),
cudaMemcpyHostToDevice);
// initialize_gpu(data,n,isize,istart); // GPU version of initialize function
MPI_Barrier(c_comm);
/* Perform forward FFT */
f_time -= MPI_Wtime();
accfft_execute_r2c_gpu(plan, data, data_hat);
f_time += MPI_Wtime();
MPI_Barrier(c_comm);
double *data2_cpu, *data2;
cudaMalloc((void**) &data2,
isize[0] * isize[1] * isize[2] * sizeof(double));
data2_cpu = (double*) malloc(
isize[0] * isize[1] * isize[2] * sizeof(double));
/* Perform backward FFT */
i_time -= MPI_Wtime();
accfft_execute_c2r_gpu(plan, data_hat, data2);
i_time += MPI_Wtime();
/* copy back results on CPU */
cudaMemcpy(data2_cpu, data2,
isize[0] * isize[1] * isize[2] * sizeof(double),
cudaMemcpyDeviceToHost);
/* Check Error */
double err = 0, g_err = 0;
double norm = 0, g_norm = 0;
for (int i = 0; i < isize[0] * isize[1] * isize[2]; ++i) {
err += std::abs(data2_cpu[i] / n[0] / n[1] / n[2] - data_cpu[i]);
norm += std::abs(data_cpu[i]);
}
MPI_Reduce(&err, &g_err, 1, MPI_DOUBLE, MPI_SUM, 0, MPI_COMM_WORLD);
MPI_Reduce(&norm, &g_norm, 1, MPI_DOUBLE, MPI_SUM, 0, MPI_COMM_WORLD);
PCOUT << "\nL1 Error is " << g_err << std::endl;
PCOUT << "Relative L1 Error is " << g_err / g_norm << std::endl;
if (g_err / g_norm < 1e-10)
PCOUT << "\nResults are CORRECT!\n\n";
else
PCOUT << "\nResults are NOT CORRECT!\n\n";
check_err(data2_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);
free(data2_cpu);
cudaFree(data);
cudaFree(data_hat);
cudaFree(data2);
accfft_destroy_plan_gpu(plan);
accfft_cleanup_gpu();
MPI_Comm_free(&c_comm);
return;
} // end step1_gpu
void accfft_execute_r2c_gpu_t(accfft_plan_gpu* plan, T* data,Tc* data_out, double * timer,std::bitset<3> XYZ){
accfft_execute_r2c_gpu(plan,data,data_out,timer,XYZ);
return;
}
