Hi,
I’m trying to execute a slightly modified example from the CUDA examples directory (conjugateGradient). I replaced cusparseScsrmv by an OpenACC kernel acc parallel loop. When I execute the program I get the following error message. What is the reason for this error?
I use the PGI compiler 19.10 and the CUDA toolkit 10.2.89.
Thank you for your help
GPU Device 0: "Tesla V100-SXM2-16GB" with compute capability 7.0
> GPU device has 80 Multi-Processors, SM 7.0 compute capabilities
cudaLaunchKernel returned status 98: invalid device function
makfile
PROG=conjugateGradient
CC=pgc++
CCU=nvcc -ccbin=${CC}
OBJS=main.o
OPTS=-ta=tesla:cc70 -acc -Minfo=accel -Minfo
INCLUDES=-I../common/inc
LIBS=-Mcudalib=cublas,cusparse
%.o: %.cu
${CCU} -arch=compute_70 -code=sm_70 -rdc=true -Xcompiler "${OPTS}" ${INCLUDES} -c $<
all:${PROG}
${PROG}:${OBJS}
${CC} -Mcuda ${OPTS} ${LIBS} -o $@ ${OBJS}
clean:
rm -f conjugateGradient main.o
main.cu
/*
* This sample implements a conjugate gradient solver on GPU
* using CUBLAS and CUSPARSE
*
*/
// includes, system
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
/* Using updated (v2) interfaces to cublas */
#include <cuda_runtime.h>
#include <cusparse.h>
#include <cublas_v2.h>
// Utilities and system includes
#include <helper_functions.h> // helper for shared functions common to CUDA Samples
#include <helper_cuda.h> // helper function CUDA error checking and initialization
const char *sSDKname = "conjugateGradient";
/* genTridiag: generate a random tridiagonal symmetric matrix */
void genTridiag(int *I, int *J, float *val, int N, int nz)
{
I[0] = 0, J[0] = 0, J[1] = 1;
val[0] = (float)rand()/RAND_MAX + 10.0f;
val[1] = (float)rand()/RAND_MAX;
int start;
for (int i = 1; i < N; i++)
{
if (i > 1)
{
I[i] = I[i-1]+3;
}
else
{
I[1] = 2;
}
start = (i-1)*3 + 2;
J[start] = i - 1;
J[start+1] = i;
if (i < N-1)
{
J[start+2] = i + 1;
}
val[start] = val[start-1];
val[start+1] = (float)rand()/RAND_MAX + 10.0f;
if (i < N-1)
{
val[start+2] = (float)rand()/RAND_MAX;
}
}
I[N] = nz;
}
int main(int argc, char **argv)
{
int M = 0, N = 0, nz = 0, *I = NULL, *J = NULL;
float *val = NULL;
const float tol = 1e-5f;
const int max_iter = 10000;
float *x;
float *rhs;
float a, b, na, r0, r1;
int *d_col, *d_row;
float *d_val, *d_x, dot;
float *d_r, *d_p, *d_Ax;
int k;
float alpha, beta, alpham1;
// This will pick the best possible CUDA capable device
cudaDeviceProp deviceProp;
int devID = findCudaDevice(argc, (const char **)argv);
if (devID < 0)
{
printf("exiting...\n");
exit(EXIT_SUCCESS);
}
checkCudaErrors(cudaGetDeviceProperties(&deviceProp, devID));
// Statistics about the GPU device
printf("> GPU device has %d Multi-Processors, SM %d.%d compute capabilities\n\n",
deviceProp.multiProcessorCount, deviceProp.major, deviceProp.minor);
/* Generate a random tridiagonal symmetric matrix in CSR format */
M = N = 1048576;
nz = (N-2)*3 + 4;
I = (int *)malloc(sizeof(int)*(N+1));
J = (int *)malloc(sizeof(int)*nz);
val = (float *)malloc(sizeof(float)*nz);
genTridiag(I, J, val, N, nz);
x = (float *)malloc(sizeof(float)*N);
rhs = (float *)malloc(sizeof(float)*N);
for (int i = 0; i < N; i++)
{
rhs[i] = 1.0;
x[i] = 0.0;
}
/* Get handle to the CUBLAS context */
cublasHandle_t cublasHandle = 0;
cublasStatus_t cublasStatus;
cublasStatus = cublasCreate(&cublasHandle);
checkCudaErrors(cublasStatus);
/* Get handle to the CUSPARSE context */
cusparseHandle_t cusparseHandle = 0;
cusparseStatus_t cusparseStatus;
cusparseStatus = cusparseCreate(&cusparseHandle);
checkCudaErrors(cusparseStatus);
cusparseMatDescr_t descr = 0;
cusparseStatus = cusparseCreateMatDescr(&descr);
checkCudaErrors(cusparseStatus);
cusparseSetMatType(descr,CUSPARSE_MATRIX_TYPE_GENERAL);
cusparseSetMatIndexBase(descr,CUSPARSE_INDEX_BASE_ZERO);
checkCudaErrors(cudaMalloc((void **)&d_col, nz*sizeof(int)));
checkCudaErrors(cudaMalloc((void **)&d_row, (N+1)*sizeof(int)));
checkCudaErrors(cudaMalloc((void **)&d_val, nz*sizeof(float)));
checkCudaErrors(cudaMalloc((void **)&d_x, N*sizeof(float)));
checkCudaErrors(cudaMalloc((void **)&d_r, N*sizeof(float)));
checkCudaErrors(cudaMalloc((void **)&d_p, N*sizeof(float)));
checkCudaErrors(cudaMalloc((void **)&d_Ax, N*sizeof(float)));
cudaMemcpy(d_col, J, nz*sizeof(int), cudaMemcpyHostToDevice);
cudaMemcpy(d_row, I, (N+1)*sizeof(int), cudaMemcpyHostToDevice);
cudaMemcpy(d_val, val, nz*sizeof(float), cudaMemcpyHostToDevice);
cudaMemcpy(d_x, x, N*sizeof(float), cudaMemcpyHostToDevice);
cudaMemcpy(d_r, rhs, N*sizeof(float), cudaMemcpyHostToDevice);
alpha = 1.0;
alpham1 = -1.0;
beta = 0.0;
r0 = 0.;
cusparseScsrmv(cusparseHandle,CUSPARSE_OPERATION_NON_TRANSPOSE, N, N, nz, &alpha, descr, d_val, d_row, d_col, d_x, &beta, d_Ax);
cublasSaxpy(cublasHandle, N, &alpham1, d_Ax, 1, d_r, 1);
cublasStatus = cublasSdot(cublasHandle, N, d_r, 1, d_r, 1, &r1);
k = 1;
cudaEvent_t start;
cudaEvent_t end;
cudaEventCreate(&start);
cudaEventCreate(&end);
float millis = 0.0;
while (r1 > tol*tol && k <= max_iter)
{
if (k > 1)
{
b = r1 / r0;
cublasStatus = cublasSscal(cublasHandle, N, &b, d_p, 1);
cublasStatus = cublasSaxpy(cublasHandle, N, &alpha, d_r, 1, d_p, 1);
}
else
{
cublasStatus = cublasScopy(cublasHandle, N, d_r, 1, d_p, 1);
}
cudaEventRecord(start);
if(0){
cusparseScsrmv(cusparseHandle, CUSPARSE_OPERATION_NON_TRANSPOSE,
N, N, nz, &alpha, descr, d_val,
d_row, d_col, d_p, &beta, d_Ax);
}else{
#pragma acc parallel loop deviceptr(d_val, d_row, d_col, d_p, d_Ax)
for(int i=0;i<N;i++)
{
double dot = 0.0;
int row_start = d_row[i];
int row_end = d_row[i+1];
#pragma acc loop seq
for(int elem = row_start; elem < row_end; elem++)
{
dot += d_val[elem] * d_p[d_col[elem]];
}
d_Ax[i] = alpha*dot + beta*d_Ax[i];
}
}
cudaEventRecord(end);
cudaEventSynchronize(end);
cudaEventElapsedTime(&millis, start, end);
cublasStatus = cublasSdot(cublasHandle, N, d_p, 1, d_Ax, 1, &dot);
a = r1 / dot;
cublasStatus = cublasSaxpy(cublasHandle, N, &a, d_p, 1, d_x, 1);
na = -a;
cublasStatus = cublasSaxpy(cublasHandle, N, &na, d_Ax, 1, d_r, 1);
r0 = r1;
cublasStatus = cublasSdot(cublasHandle, N, d_r, 1, d_r, 1, &r1);
cudaDeviceSynchronize();
printf("iteration = %3d, residual = %e\n", k, sqrt(r1));
k++;
}
cudaMemcpy(x, d_x, N*sizeof(float), cudaMemcpyDeviceToHost);
float rsum, diff, err = 0.0;
for (int i = 0; i < N; i++)
{
rsum = 0.0;
for (int j = I[i]; j < I[i+1]; j++)
{
rsum += val[j]*x[J[j]];
}
diff = fabs(rsum - rhs[i]);
if (diff > err)
{
err = diff;
}
}
cusparseDestroy(cusparseHandle);
cublasDestroy(cublasHandle);
free(I);
free(J);
free(val);
free(x);
free(rhs);
cudaFree(d_col);
cudaFree(d_row);
cudaFree(d_val);
cudaFree(d_x);
cudaFree(d_r);
cudaFree(d_p);
cudaFree(d_Ax);
printf("Test Summary: Error amount = %f\n", err);
if(CUDA_SPMV)
printf("CUDA-SpMV time: %f\n", millis*1000);
else
printf("SpMV time: %f\n", millis*1000);
exit((k <= max_iter) ? 0 : 1);
}