void grad(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 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=(double*)accfft_alloc(isize[0]*isize[1]*isize[2]*sizeof(double));
double * data_cpu=(double*)accfft_alloc(alloc_max);
double* data;
Complex* data_hat;
cudaMalloc((void**) &data , alloc_max);
cudaMalloc((void**) &data_hat, alloc_max);
accfft_init();
/* 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();
/* Initialize data */
initialize(data_cpu,n,c_comm);
cudaMemcpy(data, data_cpu,alloc_max, cudaMemcpyHostToDevice);
MPI_Barrier(c_comm);
double * gradx,*grady, *gradz;
cudaMalloc((void**) &gradx , alloc_max);
cudaMalloc((void**) &grady , alloc_max);
cudaMalloc((void**) &gradz , alloc_max);
double timings[5]={0};
std::bitset<3> XYZ=0;
XYZ[0]=1;
XYZ[1]=1;
XYZ[2]=1;
double exec_time=-MPI_Wtime();
accfft_grad_gpu(gradx,grady,gradz,data,plan,XYZ,timings);
exec_time+=MPI_Wtime();
/* Check err*/
PCOUT<<">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>"<<std::endl;
PCOUT<<">>>>>>>>Checking Gradx>>>>>>>>"<<std::endl;
cudaMemcpy(data_cpu, gradx, alloc_max, cudaMemcpyDeviceToHost);
check_err_grad(data_cpu,n,c_comm,0);
PCOUT<<"<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<"<<std::endl;
PCOUT<<"<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"<<std::endl;
PCOUT<<">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>"<<std::endl;
PCOUT<<">>>>>>>>Checking Grady>>>>>>>>"<<std::endl;
cudaMemcpy(data_cpu, grady, alloc_max, cudaMemcpyDeviceToHost);
check_err_grad(data_cpu,n,c_comm,1);
PCOUT<<"<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<"<<std::endl;
PCOUT<<"<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"<<std::endl;
PCOUT<<">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>"<<std::endl;
PCOUT<<">>>>>>>>Checking Gradz>>>>>>>>"<<std::endl;
cudaMemcpy(data_cpu, gradz, alloc_max, cudaMemcpyDeviceToHost);
check_err_grad(data_cpu,n,c_comm,2);
PCOUT<<"<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<"<<std::endl;
PCOUT<<"<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"<<std::endl;
/* Compute some timings statistics */
double g_setup_time,g_timings[5],g_exec_time;
MPI_Reduce(timings,g_timings,5, MPI_DOUBLE, MPI_MAX,0, c_comm);
MPI_Reduce(&setup_time,&g_setup_time,1, MPI_DOUBLE, MPI_MAX,0, c_comm);
MPI_Reduce(&exec_time,&g_exec_time,1, MPI_DOUBLE, MPI_MAX,0, c_comm);
PCOUT<<"Timing for Grad Computation for size "<<n[0]<<"*"<<n[1]<<"*"<<n[2]<<std::endl;
PCOUT<<"Setup \t\t"<<g_setup_time<<std::endl;
PCOUT<<"Evaluation \t"<<g_exec_time<<std::endl;
accfft_free(data_cpu);
cudaFree(data);
cudaFree(data_hat);
MPI_Barrier(c_comm);
cudaFree(gradx);
cudaFree(grady);
cudaFree(gradz);
accfft_destroy_plan(plan);
accfft_cleanup_gpu();
MPI_Comm_free(&c_comm);
PCOUT<<"-------------------------------------------------------"<<std::endl;
PCOUT<<"-------------------------------------------------------"<<std::endl;
PCOUT<<"-------------------------------------------------------\n"<<std::endl;
return ;
} // end grad
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