Actual source code: aijcusparse.cu

  1: /*
  2:   Defines the basic matrix operations for the AIJ (compressed row)
  3:   matrix storage format using the CUSPARSE library,
  4: */
  5: #define PETSC_SKIP_IMMINTRIN_H_CUDAWORKAROUND 1

  7: #include <petscconf.h>
  8: #include <../src/mat/impls/aij/seq/aij.h>
  9: #include <../src/mat/impls/sbaij/seq/sbaij.h>
 10: #include <../src/vec/vec/impls/dvecimpl.h>
 11: #include <petsc/private/vecimpl.h>
 12: #undef VecType
 13: #include <../src/mat/impls/aij/seq/seqcusparse/cusparsematimpl.h>
 14: #include <thrust/adjacent_difference.h>
 15: #if PETSC_CPP_VERSION >= 14
 16:   #define PETSC_HAVE_THRUST_ASYNC 1
 17: // thrust::for_each(thrust::cuda::par.on()) requires C++14
 18: #endif
 19: #include <thrust/iterator/constant_iterator.h>
 20: #include <thrust/remove.h>
 21: #include <thrust/sort.h>
 22: #include <thrust/unique.h>
 23: #if PETSC_PKG_CUDA_VERSION_GE(12, 9, 0) && !PetscDefined(HAVE_THRUST)
 24:   #include <cuda/std/functional>
 25: #endif

 27: const char *const MatCUSPARSEStorageFormats[] = {"CSR", "ELL", "HYB", "MatCUSPARSEStorageFormat", "MAT_CUSPARSE_", 0};
 28: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
 29: /*
 30:   The following are copied from cusparse.h in CUDA-11.0. In MatCUSPARSESpMVAlgorithms[] etc, we copy them in
 31:   0-based integer value order, since we want to use PetscOptionsEnum() to parse user command line options for them.
 32: */
 33: const char *const MatCUSPARSESpMVAlgorithms[]    = {"MV_ALG_DEFAULT", "COOMV_ALG", "CSRMV_ALG1", "CSRMV_ALG2", "cusparseSpMVAlg_t", "CUSPARSE_", 0};
 34: const char *const MatCUSPARSESpMMAlgorithms[]    = {"ALG_DEFAULT", "COO_ALG1", "COO_ALG2", "COO_ALG3", "CSR_ALG1", "COO_ALG4", "CSR_ALG2", "cusparseSpMMAlg_t", "CUSPARSE_SPMM_", 0};
 35: const char *const MatCUSPARSECsr2CscAlgorithms[] = {"INVALID" /*cusparse does not have enum 0! We created one*/, "ALG1", "ALG2", "cusparseCsr2CscAlg_t", "CUSPARSE_CSR2CSC_", 0};
 36: #endif

 38: static PetscErrorCode MatICCFactorSymbolic_SeqAIJCUSPARSE(Mat, Mat, IS, const MatFactorInfo *);
 39: static PetscErrorCode MatCholeskyFactorSymbolic_SeqAIJCUSPARSE(Mat, Mat, IS, const MatFactorInfo *);
 40: static PetscErrorCode MatCholeskyFactorNumeric_SeqAIJCUSPARSE(Mat, Mat, const MatFactorInfo *);
 41: static PetscErrorCode MatILUFactorSymbolic_SeqAIJCUSPARSE(Mat, Mat, IS, IS, const MatFactorInfo *);
 42: #if PETSC_PKG_CUDA_VERSION_LT(11, 4, 0)
 43: static PetscErrorCode MatSolve_SeqAIJCUSPARSE(Mat, Vec, Vec);
 44: static PetscErrorCode MatSolveTranspose_SeqAIJCUSPARSE(Mat, Vec, Vec);
 45: static PetscErrorCode MatSolve_SeqAIJCUSPARSE_NaturalOrdering(Mat, Vec, Vec);
 46: static PetscErrorCode MatSolveTranspose_SeqAIJCUSPARSE_NaturalOrdering(Mat, Vec, Vec);
 47: static PetscErrorCode MatSeqAIJCUSPARSEMultStruct_Destroy(Mat_SeqAIJCUSPARSETriFactorStruct **);
 48: #endif
 49: static PetscErrorCode MatSetFromOptions_SeqAIJCUSPARSE(Mat, PetscOptionItems PetscOptionsObject);
 50: static PetscErrorCode MatAXPY_SeqAIJCUSPARSE(Mat, PetscScalar, Mat, MatStructure);
 51: static PetscErrorCode MatScale_SeqAIJCUSPARSE(Mat, PetscScalar);
 52: static PetscErrorCode MatMult_SeqAIJCUSPARSE(Mat, Vec, Vec);
 53: static PetscErrorCode MatMultAdd_SeqAIJCUSPARSE(Mat, Vec, Vec, Vec);
 54: static PetscErrorCode MatMultTranspose_SeqAIJCUSPARSE(Mat, Vec, Vec);
 55: static PetscErrorCode MatMultTransposeAdd_SeqAIJCUSPARSE(Mat, Vec, Vec, Vec);
 56: static PetscErrorCode MatMultHermitianTranspose_SeqAIJCUSPARSE(Mat, Vec, Vec);
 57: static PetscErrorCode MatMultHermitianTransposeAdd_SeqAIJCUSPARSE(Mat, Vec, Vec, Vec);
 58: static PetscErrorCode MatMultAddKernel_SeqAIJCUSPARSE(Mat, Vec, Vec, Vec, PetscBool, PetscBool);

 60: static PetscErrorCode CsrMatrix_Destroy(CsrMatrix **);
 61: static PetscErrorCode MatSeqAIJCUSPARSEMultStruct_Destroy(Mat_SeqAIJCUSPARSEMultStruct **, MatCUSPARSEStorageFormat);
 62: static PetscErrorCode MatSeqAIJCUSPARSETriFactors_Destroy(Mat_SeqAIJCUSPARSETriFactors **);
 63: static PetscErrorCode MatSeqAIJCUSPARSE_Destroy(Mat);

 65: static PetscErrorCode MatSeqAIJCUSPARSECopyFromGPU(Mat);
 66: static PetscErrorCode MatSeqAIJCUSPARSEInvalidateTranspose(Mat, PetscBool);

 68: static PetscErrorCode MatSeqAIJCopySubArray_SeqAIJCUSPARSE(Mat, PetscInt, const PetscInt[], PetscScalar[]);
 69: static PetscErrorCode MatSetPreallocationCOO_SeqAIJCUSPARSE(Mat, PetscCount, PetscInt[], PetscInt[]);
 70: static PetscErrorCode MatSetValuesCOO_SeqAIJCUSPARSE(Mat, const PetscScalar[], InsertMode);

 72: PETSC_INTERN PetscErrorCode MatCUSPARSESetFormat_SeqAIJCUSPARSE(Mat A, MatCUSPARSEFormatOperation op, MatCUSPARSEStorageFormat format)
 73: {
 74:   Mat_SeqAIJCUSPARSE *cusparsestruct = (Mat_SeqAIJCUSPARSE *)A->spptr;

 76:   PetscFunctionBegin;
 77:   switch (op) {
 78:   case MAT_CUSPARSE_MULT:
 79:     cusparsestruct->format = format;
 80:     break;
 81:   case MAT_CUSPARSE_ALL:
 82:     cusparsestruct->format = format;
 83:     break;
 84:   default:
 85:     SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "unsupported operation %d for MatCUSPARSEFormatOperation. MAT_CUSPARSE_MULT and MAT_CUSPARSE_ALL are currently supported.", op);
 86:   }
 87:   PetscFunctionReturn(PETSC_SUCCESS);
 88: }

 90: /*@
 91:   MatCUSPARSESetFormat - Sets the storage format of `MATSEQCUSPARSE` matrices for a particular
 92:   operation. Only the `MatMult()` operation can use different GPU storage formats

 94:   Not Collective

 96:   Input Parameters:
 97: + A      - Matrix of type `MATSEQAIJCUSPARSE`
 98: . op     - `MatCUSPARSEFormatOperation`. `MATSEQAIJCUSPARSE` matrices support `MAT_CUSPARSE_MULT` and `MAT_CUSPARSE_ALL`.
 99:            `MATMPIAIJCUSPARSE` matrices support `MAT_CUSPARSE_MULT_DIAG`,`MAT_CUSPARSE_MULT_OFFDIAG`, and `MAT_CUSPARSE_ALL`.
100: - format - `MatCUSPARSEStorageFormat` (one of `MAT_CUSPARSE_CSR`, `MAT_CUSPARSE_ELL`, `MAT_CUSPARSE_HYB`.)

102:   Level: intermediate

104: .seealso: [](ch_matrices), `Mat`, `MATSEQAIJCUSPARSE`, `MatCUSPARSEStorageFormat`, `MatCUSPARSEFormatOperation`
105: @*/
106: PetscErrorCode MatCUSPARSESetFormat(Mat A, MatCUSPARSEFormatOperation op, MatCUSPARSEStorageFormat format)
107: {
108:   PetscFunctionBegin;
110:   PetscTryMethod(A, "MatCUSPARSESetFormat_C", (Mat, MatCUSPARSEFormatOperation, MatCUSPARSEStorageFormat), (A, op, format));
111:   PetscFunctionReturn(PETSC_SUCCESS);
112: }

114: PETSC_INTERN PetscErrorCode MatCUSPARSESetUseCPUSolve_SeqAIJCUSPARSE(Mat A, PetscBool use_cpu)
115: {
116:   Mat_SeqAIJCUSPARSE *cusparsestruct = (Mat_SeqAIJCUSPARSE *)A->spptr;

118:   PetscFunctionBegin;
119:   cusparsestruct->use_cpu_solve = use_cpu;
120:   PetscFunctionReturn(PETSC_SUCCESS);
121: }

123: /*@
124:   MatCUSPARSESetUseCPUSolve - Sets to use CPU `MatSolve()`.

126:   Input Parameters:
127: + A       - Matrix of type `MATSEQAIJCUSPARSE`
128: - use_cpu - set flag for using the built-in CPU `MatSolve()`

130:   Level: intermediate

132:   Note:
133:   The NVIDIA cuSPARSE LU solver currently computes the factors with the built-in CPU method
134:   and moves the factors to the GPU for the solve. We have observed better performance keeping the data on the CPU and performing the solve there.
135:   This method to specify if the solve is done on the CPU or GPU (GPU is the default).

137: .seealso: [](ch_matrices), `Mat`, `MatSolve()`, `MATSEQAIJCUSPARSE`, `MatCUSPARSEStorageFormat`, `MatCUSPARSEFormatOperation`
138: @*/
139: PetscErrorCode MatCUSPARSESetUseCPUSolve(Mat A, PetscBool use_cpu)
140: {
141:   PetscFunctionBegin;
143:   PetscTryMethod(A, "MatCUSPARSESetUseCPUSolve_C", (Mat, PetscBool), (A, use_cpu));
144:   PetscFunctionReturn(PETSC_SUCCESS);
145: }

147: static PetscErrorCode MatSetOption_SeqAIJCUSPARSE(Mat A, MatOption op, PetscBool flg)
148: {
149:   PetscFunctionBegin;
150:   switch (op) {
151:   case MAT_FORM_EXPLICIT_TRANSPOSE:
152:     /* need to destroy the transpose matrix if present to prevent from logic errors if flg is set to true later */
153:     if (A->form_explicit_transpose && !flg) PetscCall(MatSeqAIJCUSPARSEInvalidateTranspose(A, PETSC_TRUE));
154:     A->form_explicit_transpose = flg;
155:     break;
156:   default:
157:     PetscCall(MatSetOption_SeqAIJ(A, op, flg));
158:     break;
159:   }
160:   PetscFunctionReturn(PETSC_SUCCESS);
161: }

163: static PetscErrorCode MatSetFromOptions_SeqAIJCUSPARSE(Mat A, PetscOptionItems PetscOptionsObject)
164: {
165:   MatCUSPARSEStorageFormat format;
166:   PetscBool                flg;
167:   Mat_SeqAIJCUSPARSE      *cusparsestruct = (Mat_SeqAIJCUSPARSE *)A->spptr;

169:   PetscFunctionBegin;
170:   PetscOptionsHeadBegin(PetscOptionsObject, "SeqAIJCUSPARSE options");
171:   if (A->factortype == MAT_FACTOR_NONE) {
172:     PetscCall(PetscOptionsEnum("-mat_cusparse_mult_storage_format", "sets storage format of (seq)aijcusparse gpu matrices for SpMV", "MatCUSPARSESetFormat", MatCUSPARSEStorageFormats, (PetscEnum)cusparsestruct->format, (PetscEnum *)&format, &flg));
173:     if (flg) PetscCall(MatCUSPARSESetFormat(A, MAT_CUSPARSE_MULT, format));

175:     PetscCall(PetscOptionsEnum("-mat_cusparse_storage_format", "sets storage format of (seq)aijcusparse gpu matrices for SpMV and TriSolve", "MatCUSPARSESetFormat", MatCUSPARSEStorageFormats, (PetscEnum)cusparsestruct->format, (PetscEnum *)&format, &flg));
176:     if (flg) PetscCall(MatCUSPARSESetFormat(A, MAT_CUSPARSE_ALL, format));
177:     PetscCall(PetscOptionsBool("-mat_cusparse_use_cpu_solve", "Use CPU (I)LU solve", "MatCUSPARSESetUseCPUSolve", cusparsestruct->use_cpu_solve, &cusparsestruct->use_cpu_solve, &flg));
178:     if (flg) PetscCall(MatCUSPARSESetUseCPUSolve(A, cusparsestruct->use_cpu_solve));
179: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
180:     PetscCall(PetscOptionsEnum("-mat_cusparse_spmv_alg", "sets cuSPARSE algorithm used in sparse-mat dense-vector multiplication (SpMV)", "cusparseSpMVAlg_t", MatCUSPARSESpMVAlgorithms, (PetscEnum)cusparsestruct->spmvAlg, (PetscEnum *)&cusparsestruct->spmvAlg, &flg));
181:     /* If user did use this option, check its consistency with cuSPARSE, since PetscOptionsEnum() sets enum values based on their position in MatCUSPARSESpMVAlgorithms[] */
182:   #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
183:     PetscCheck(!flg || CUSPARSE_SPMV_CSR_ALG1 == 2, PETSC_COMM_SELF, PETSC_ERR_SUP, "cuSPARSE enum cusparseSpMVAlg_t has been changed but PETSc has not been updated accordingly");
184:   #else
185:     PetscCheck(!flg || CUSPARSE_CSRMV_ALG1 == 2, PETSC_COMM_SELF, PETSC_ERR_SUP, "cuSPARSE enum cusparseSpMVAlg_t has been changed but PETSc has not been updated accordingly");
186:   #endif
187:     PetscCall(PetscOptionsEnum("-mat_cusparse_spmm_alg", "sets cuSPARSE algorithm used in sparse-mat dense-mat multiplication (SpMM)", "cusparseSpMMAlg_t", MatCUSPARSESpMMAlgorithms, (PetscEnum)cusparsestruct->spmmAlg, (PetscEnum *)&cusparsestruct->spmmAlg, &flg));
188:     PetscCheck(!flg || CUSPARSE_SPMM_CSR_ALG1 == 4, PETSC_COMM_SELF, PETSC_ERR_SUP, "cuSPARSE enum cusparseSpMMAlg_t has been changed but PETSc has not been updated accordingly");

190:     PetscCall(
191:       PetscOptionsEnum("-mat_cusparse_csr2csc_alg", "sets cuSPARSE algorithm used in converting CSR matrices to CSC matrices", "cusparseCsr2CscAlg_t", MatCUSPARSECsr2CscAlgorithms, (PetscEnum)cusparsestruct->csr2cscAlg, (PetscEnum *)&cusparsestruct->csr2cscAlg, &flg));
192:     PetscCheck(!flg || CUSPARSE_CSR2CSC_ALG1 == 1, PETSC_COMM_SELF, PETSC_ERR_SUP, "cuSPARSE enum cusparseCsr2CscAlg_t has been changed but PETSc has not been updated accordingly");
193: #endif
194:   }
195:   PetscOptionsHeadEnd();
196:   PetscFunctionReturn(PETSC_SUCCESS);
197: }

199: #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
200: static PetscErrorCode MatSeqAIJCUSPARSEBuildFactoredMatrix_LU(Mat A)
201: {
202:   Mat_SeqAIJ                   *a  = static_cast<Mat_SeqAIJ *>(A->data);
203:   PetscInt                      m  = A->rmap->n;
204:   Mat_SeqAIJCUSPARSETriFactors *fs = static_cast<Mat_SeqAIJCUSPARSETriFactors *>(A->spptr);
205:   const PetscInt               *Ai = a->i, *Aj = a->j, *adiag;
206:   const MatScalar              *Aa = a->a;
207:   PetscInt                     *Mi, *Mj, Mnz;
208:   PetscScalar                  *Ma;

210:   PetscFunctionBegin;
211:   PetscCall(MatGetDiagonalMarkers_SeqAIJ(A, &adiag, NULL));
212:   if (A->offloadmask == PETSC_OFFLOAD_CPU) { // A's latest factors are on CPU
213:     if (!fs->csrRowPtr) {                    // Is't the first time to do the setup? Use csrRowPtr since it is not null even when m=0
214:       // Re-arrange the (skewed) factored matrix and put the result into M, a regular csr matrix on host
215:       Mnz = (Ai[m] - Ai[0]) + (adiag[0] - adiag[m]); // Lnz (without the unit diagonal) + Unz (with the non-unit diagonal)
216:       PetscCall(PetscMalloc1(m + 1, &Mi));
217:       PetscCall(PetscMalloc1(Mnz, &Mj)); // Mj is temp
218:       PetscCall(PetscMalloc1(Mnz, &Ma));
219:       Mi[0] = 0;
220:       for (PetscInt i = 0; i < m; i++) {
221:         PetscInt llen = Ai[i + 1] - Ai[i];
222:         PetscInt ulen = adiag[i] - adiag[i + 1];
223:         PetscCall(PetscArraycpy(Mj + Mi[i], Aj + Ai[i], llen));                           // entries of L
224:         Mj[Mi[i] + llen] = i;                                                             // diagonal entry
225:         PetscCall(PetscArraycpy(Mj + Mi[i] + llen + 1, Aj + adiag[i + 1] + 1, ulen - 1)); // entries of U on the right of the diagonal
226:         Mi[i + 1] = Mi[i] + llen + ulen;
227:       }
228:       // Copy M (L,U) from host to device
229:       PetscCallCUDA(cudaMalloc(&fs->csrRowPtr, sizeof(*fs->csrRowPtr) * (m + 1)));
230:       PetscCallCUDA(cudaMalloc(&fs->csrColIdx, sizeof(*fs->csrColIdx) * Mnz));
231:       PetscCallCUDA(cudaMalloc(&fs->csrVal, sizeof(*fs->csrVal) * Mnz));
232:       PetscCallCUDA(cudaMemcpy(fs->csrRowPtr, Mi, sizeof(*fs->csrRowPtr) * (m + 1), cudaMemcpyHostToDevice));
233:       PetscCallCUDA(cudaMemcpy(fs->csrColIdx, Mj, sizeof(*fs->csrColIdx) * Mnz, cudaMemcpyHostToDevice));

235:       // Create descriptors for L, U. See https://docs.nvidia.com/cuda/cusparse/index.html#cusparseDiagType_t
236:       // cusparseDiagType_t: This type indicates if the matrix diagonal entries are unity. The diagonal elements are always
237:       // assumed to be present, but if CUSPARSE_DIAG_TYPE_UNIT is passed to an API routine, then the routine assumes that
238:       // all diagonal entries are unity and will not read or modify those entries. Note that in this case the routine
239:       // assumes the diagonal entries are equal to one, regardless of what those entries are actually set to in memory.
240:       cusparseFillMode_t        fillMode  = CUSPARSE_FILL_MODE_LOWER;
241:       cusparseDiagType_t        diagType  = CUSPARSE_DIAG_TYPE_UNIT;
242:       const cusparseIndexType_t indexType = PetscDefined(USE_64BIT_INDICES) ? CUSPARSE_INDEX_64I : CUSPARSE_INDEX_32I;

244:       PetscCallCUSPARSE(cusparseCreateCsr(&fs->spMatDescr_L, m, m, Mnz, fs->csrRowPtr, fs->csrColIdx, fs->csrVal, indexType, indexType, CUSPARSE_INDEX_BASE_ZERO, cusparse_scalartype));
245:       PetscCallCUSPARSE(cusparseSpMatSetAttribute(fs->spMatDescr_L, CUSPARSE_SPMAT_FILL_MODE, &fillMode, sizeof(fillMode)));
246:       PetscCallCUSPARSE(cusparseSpMatSetAttribute(fs->spMatDescr_L, CUSPARSE_SPMAT_DIAG_TYPE, &diagType, sizeof(diagType)));

248:       fillMode = CUSPARSE_FILL_MODE_UPPER;
249:       diagType = CUSPARSE_DIAG_TYPE_NON_UNIT;
250:       PetscCallCUSPARSE(cusparseCreateCsr(&fs->spMatDescr_U, m, m, Mnz, fs->csrRowPtr, fs->csrColIdx, fs->csrVal, indexType, indexType, CUSPARSE_INDEX_BASE_ZERO, cusparse_scalartype));
251:       PetscCallCUSPARSE(cusparseSpMatSetAttribute(fs->spMatDescr_U, CUSPARSE_SPMAT_FILL_MODE, &fillMode, sizeof(fillMode)));
252:       PetscCallCUSPARSE(cusparseSpMatSetAttribute(fs->spMatDescr_U, CUSPARSE_SPMAT_DIAG_TYPE, &diagType, sizeof(diagType)));

254:       // Allocate work vectors in SpSv
255:       PetscCallCUDA(cudaMalloc((void **)&fs->X, sizeof(*fs->X) * m));
256:       PetscCallCUDA(cudaMalloc((void **)&fs->Y, sizeof(*fs->Y) * m));

258:       PetscCallCUSPARSE(cusparseCreateDnVec(&fs->dnVecDescr_X, m, fs->X, cusparse_scalartype));
259:       PetscCallCUSPARSE(cusparseCreateDnVec(&fs->dnVecDescr_Y, m, fs->Y, cusparse_scalartype));

261:       // Query buffer sizes for SpSV and then allocate buffers, temporarily assuming opA = CUSPARSE_OPERATION_NON_TRANSPOSE
262:       PetscCallCUSPARSE(cusparseSpSV_createDescr(&fs->spsvDescr_L));
263:       PetscCallCUSPARSE(cusparseSpSV_bufferSize(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_L, &fs->spsvBufferSize_L));
264:       PetscCallCUSPARSE(cusparseSpSV_createDescr(&fs->spsvDescr_U));
265:       PetscCallCUSPARSE(cusparseSpSV_bufferSize(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_U, &fs->spsvBufferSize_U));
266:       PetscCallCUDA(cudaMalloc((void **)&fs->spsvBuffer_U, fs->spsvBufferSize_U));
267:       PetscCallCUDA(cudaMalloc((void **)&fs->spsvBuffer_L, fs->spsvBufferSize_L));

269:       // Record for reuse
270:       fs->csrRowPtr_h = Mi;
271:       fs->csrVal_h    = Ma;
272:       PetscCall(PetscFree(Mj));
273:     }
274:     // Copy the value
275:     Mi  = fs->csrRowPtr_h;
276:     Ma  = fs->csrVal_h;
277:     Mnz = Mi[m];
278:     for (PetscInt i = 0; i < m; i++) {
279:       PetscInt llen = Ai[i + 1] - Ai[i];
280:       PetscInt ulen = adiag[i] - adiag[i + 1];
281:       PetscCall(PetscArraycpy(Ma + Mi[i], Aa + Ai[i], llen));                           // entries of L
282:       Ma[Mi[i] + llen] = (MatScalar)1.0 / Aa[adiag[i]];                                 // recover the diagonal entry
283:       PetscCall(PetscArraycpy(Ma + Mi[i] + llen + 1, Aa + adiag[i + 1] + 1, ulen - 1)); // entries of U on the right of the diagonal
284:     }
285:     PetscCallCUDA(cudaMemcpy(fs->csrVal, Ma, sizeof(*Ma) * Mnz, cudaMemcpyHostToDevice));

287:   #if PETSC_PKG_CUDA_VERSION_GE(12, 1, 1)
288:     if (fs->updatedSpSVAnalysis) { // have done cusparseSpSV_analysis before, and only matrix values changed?
289:       // Otherwise cusparse would error out: "On entry to cusparseSpSV_updateMatrix() parameter number 3 (newValues) had an illegal value: NULL pointer"
290:       if (fs->csrVal) PetscCallCUSPARSE(cusparseSpSV_updateMatrix(fs->handle, fs->spsvDescr_L, fs->csrVal, CUSPARSE_SPSV_UPDATE_GENERAL));
291:       if (fs->csrVal) PetscCallCUSPARSE(cusparseSpSV_updateMatrix(fs->handle, fs->spsvDescr_U, fs->csrVal, CUSPARSE_SPSV_UPDATE_GENERAL));
292:     } else
293:   #endif
294:     {
295:       // Do cusparseSpSV_analysis(), which is numeric and requires valid and up-to-date matrix values
296:       PetscCallCUSPARSE(cusparseSpSV_analysis(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_L, fs->spsvBuffer_L));

298:       PetscCallCUSPARSE(cusparseSpSV_analysis(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_U, fs->spsvBuffer_U));
299:       fs->updatedSpSVAnalysis          = PETSC_TRUE;
300:       fs->updatedTransposeSpSVAnalysis = PETSC_FALSE;
301:     }
302:   }
303:   PetscFunctionReturn(PETSC_SUCCESS);
304: }
305: #else
306: static PetscErrorCode MatSeqAIJCUSPARSEBuildILULowerTriMatrix(Mat A)
307: {
308:   Mat_SeqAIJ                        *a                  = (Mat_SeqAIJ *)A->data;
309:   PetscInt                           n                  = A->rmap->n;
310:   Mat_SeqAIJCUSPARSETriFactors      *cusparseTriFactors = (Mat_SeqAIJCUSPARSETriFactors *)A->spptr;
311:   Mat_SeqAIJCUSPARSETriFactorStruct *loTriFactor        = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->loTriFactorPtr;
312:   const PetscInt                    *ai = a->i, *aj = a->j, *vi;
313:   const MatScalar                   *aa = a->a, *v;
314:   PetscInt                          *AiLo, *AjLo;
315:   PetscInt                           i, nz, nzLower, offset, rowOffset;

317:   PetscFunctionBegin;
318:   if (!n) PetscFunctionReturn(PETSC_SUCCESS);
319:   if (A->offloadmask == PETSC_OFFLOAD_UNALLOCATED || A->offloadmask == PETSC_OFFLOAD_CPU) {
320:     try {
321:       /* first figure out the number of nonzeros in the lower triangular matrix including 1's on the diagonal. */
322:       nzLower = n + ai[n] - ai[1];
323:       if (!loTriFactor) {
324:         PetscScalar *AALo;

326:         PetscCallCUDA(cudaMallocHost((void **)&AALo, nzLower * sizeof(PetscScalar)));

328:         /* Allocate Space for the lower triangular matrix */
329:         PetscCallCUDA(cudaMallocHost((void **)&AiLo, (n + 1) * sizeof(PetscInt)));
330:         PetscCallCUDA(cudaMallocHost((void **)&AjLo, nzLower * sizeof(PetscInt)));

332:         /* Fill the lower triangular matrix */
333:         AiLo[0]   = (PetscInt)0;
334:         AiLo[n]   = nzLower;
335:         AjLo[0]   = (PetscInt)0;
336:         AALo[0]   = (MatScalar)1.0;
337:         v         = aa;
338:         vi        = aj;
339:         offset    = 1;
340:         rowOffset = 1;
341:         for (i = 1; i < n; i++) {
342:           nz = ai[i + 1] - ai[i];
343:           /* additional 1 for the term on the diagonal */
344:           AiLo[i] = rowOffset;
345:           rowOffset += nz + 1;

347:           PetscCall(PetscArraycpy(&AjLo[offset], vi, nz));
348:           PetscCall(PetscArraycpy(&AALo[offset], v, nz));

350:           offset += nz;
351:           AjLo[offset] = (PetscInt)i;
352:           AALo[offset] = (MatScalar)1.0;
353:           offset += 1;

355:           v += nz;
356:           vi += nz;
357:         }

359:         /* allocate space for the triangular factor information */
360:         PetscCall(PetscNew(&loTriFactor));
361:         loTriFactor->solvePolicy = CUSPARSE_SOLVE_POLICY_USE_LEVEL;
362:         /* Create the matrix description */
363:         PetscCallCUSPARSE(cusparseCreateMatDescr(&loTriFactor->descr));
364:         PetscCallCUSPARSE(cusparseSetMatIndexBase(loTriFactor->descr, CUSPARSE_INDEX_BASE_ZERO));
365:   #if PETSC_PKG_CUDA_VERSION_GE(9, 0, 0)
366:         PetscCallCUSPARSE(cusparseSetMatType(loTriFactor->descr, CUSPARSE_MATRIX_TYPE_GENERAL));
367:   #else
368:         PetscCallCUSPARSE(cusparseSetMatType(loTriFactor->descr, CUSPARSE_MATRIX_TYPE_TRIANGULAR));
369:   #endif
370:         PetscCallCUSPARSE(cusparseSetMatFillMode(loTriFactor->descr, CUSPARSE_FILL_MODE_LOWER));
371:         PetscCallCUSPARSE(cusparseSetMatDiagType(loTriFactor->descr, CUSPARSE_DIAG_TYPE_UNIT));

373:         /* set the operation */
374:         loTriFactor->solveOp = CUSPARSE_OPERATION_NON_TRANSPOSE;

376:         /* set the matrix */
377:         loTriFactor->csrMat              = new CsrMatrix;
378:         loTriFactor->csrMat->num_rows    = n;
379:         loTriFactor->csrMat->num_cols    = n;
380:         loTriFactor->csrMat->num_entries = nzLower;

382:         loTriFactor->csrMat->row_offsets = new THRUSTINTARRAY32(n + 1);
383:         loTriFactor->csrMat->row_offsets->assign(AiLo, AiLo + n + 1);

385:         loTriFactor->csrMat->column_indices = new THRUSTINTARRAY32(nzLower);
386:         loTriFactor->csrMat->column_indices->assign(AjLo, AjLo + nzLower);

388:         loTriFactor->csrMat->values = new THRUSTARRAY(nzLower);
389:         loTriFactor->csrMat->values->assign(AALo, AALo + nzLower);

391:         /* Create the solve analysis information */
392:         PetscCall(PetscLogEventBegin(MAT_CUSPARSESolveAnalysis, A, 0, 0, 0));
393:         PetscCallCUSPARSE(cusparseCreateCsrsvInfo(&loTriFactor->solveInfo));
394:   #if PETSC_PKG_CUDA_VERSION_GE(9, 0, 0)
395:         PetscCallCUSPARSE(cusparseXcsrsv_buffsize(cusparseTriFactors->handle, loTriFactor->solveOp, loTriFactor->csrMat->num_rows, loTriFactor->csrMat->num_entries, loTriFactor->descr, loTriFactor->csrMat->values->data().get(),
396:                                                   loTriFactor->csrMat->row_offsets->data().get(), loTriFactor->csrMat->column_indices->data().get(), loTriFactor->solveInfo, &loTriFactor->solveBufferSize));
397:         PetscCallCUDA(cudaMalloc(&loTriFactor->solveBuffer, loTriFactor->solveBufferSize));
398:   #endif

400:         /* perform the solve analysis */
401:         PetscCallCUSPARSE(cusparseXcsrsv_analysis(cusparseTriFactors->handle, loTriFactor->solveOp, loTriFactor->csrMat->num_rows, loTriFactor->csrMat->num_entries, loTriFactor->descr, loTriFactor->csrMat->values->data().get(),
402:                                                   loTriFactor->csrMat->row_offsets->data().get(), loTriFactor->csrMat->column_indices->data().get(), loTriFactor->solveInfo, loTriFactor->solvePolicy, loTriFactor->solveBuffer));
403:         PetscCallCUDA(WaitForCUDA());
404:         PetscCall(PetscLogEventEnd(MAT_CUSPARSESolveAnalysis, A, 0, 0, 0));

406:         /* assign the pointer */
407:         ((Mat_SeqAIJCUSPARSETriFactors *)A->spptr)->loTriFactorPtr = loTriFactor;
408:         loTriFactor->AA_h                                          = AALo;
409:         PetscCallCUDA(cudaFreeHost(AiLo));
410:         PetscCallCUDA(cudaFreeHost(AjLo));
411:         PetscCall(PetscLogCpuToGpu((n + 1 + nzLower) * sizeof(int) + nzLower * sizeof(PetscScalar)));
412:       } else { /* update values only */
413:         if (!loTriFactor->AA_h) PetscCallCUDA(cudaMallocHost((void **)&loTriFactor->AA_h, nzLower * sizeof(PetscScalar)));
414:         /* Fill the lower triangular matrix */
415:         loTriFactor->AA_h[0] = 1.0;
416:         v                    = aa;
417:         vi                   = aj;
418:         offset               = 1;
419:         for (i = 1; i < n; i++) {
420:           nz = ai[i + 1] - ai[i];
421:           PetscCall(PetscArraycpy(&loTriFactor->AA_h[offset], v, nz));
422:           offset += nz;
423:           loTriFactor->AA_h[offset] = 1.0;
424:           offset += 1;
425:           v += nz;
426:         }
427:         loTriFactor->csrMat->values->assign(loTriFactor->AA_h, loTriFactor->AA_h + nzLower);
428:         PetscCall(PetscLogCpuToGpu(nzLower * sizeof(PetscScalar)));
429:       }
430:     } catch (char *ex) {
431:       SETERRQ(PETSC_COMM_SELF, PETSC_ERR_LIB, "CUSPARSE error: %s", ex);
432:     }
433:   }
434:   PetscFunctionReturn(PETSC_SUCCESS);
435: }

437: static PetscErrorCode MatSeqAIJCUSPARSEBuildILUUpperTriMatrix(Mat A)
438: {
439:   Mat_SeqAIJ                        *a                  = (Mat_SeqAIJ *)A->data;
440:   PetscInt                           n                  = A->rmap->n;
441:   Mat_SeqAIJCUSPARSETriFactors      *cusparseTriFactors = (Mat_SeqAIJCUSPARSETriFactors *)A->spptr;
442:   Mat_SeqAIJCUSPARSETriFactorStruct *upTriFactor        = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->upTriFactorPtr;
443:   const PetscInt                    *aj                 = a->j, *adiag, *vi;
444:   const MatScalar                   *aa                 = a->a, *v;
445:   PetscInt                          *AiUp, *AjUp;
446:   PetscInt                           i, nz, nzUpper, offset;

448:   PetscFunctionBegin;
449:   if (!n) PetscFunctionReturn(PETSC_SUCCESS);
450:   PetscCall(MatGetDiagonalMarkers_SeqAIJ(A, &adiag, NULL));
451:   if (A->offloadmask == PETSC_OFFLOAD_UNALLOCATED || A->offloadmask == PETSC_OFFLOAD_CPU) {
452:     try {
453:       /* next, figure out the number of nonzeros in the upper triangular matrix. */
454:       nzUpper = adiag[0] - adiag[n];
455:       if (!upTriFactor) {
456:         PetscScalar *AAUp;

458:         PetscCallCUDA(cudaMallocHost((void **)&AAUp, nzUpper * sizeof(PetscScalar)));

460:         /* Allocate Space for the upper triangular matrix */
461:         PetscCallCUDA(cudaMallocHost((void **)&AiUp, (n + 1) * sizeof(PetscInt)));
462:         PetscCallCUDA(cudaMallocHost((void **)&AjUp, nzUpper * sizeof(PetscInt)));

464:         /* Fill the upper triangular matrix */
465:         AiUp[0] = (PetscInt)0;
466:         AiUp[n] = nzUpper;
467:         offset  = nzUpper;
468:         for (i = n - 1; i >= 0; i--) {
469:           v  = aa + adiag[i + 1] + 1;
470:           vi = aj + adiag[i + 1] + 1;

472:           /* number of elements NOT on the diagonal */
473:           nz = adiag[i] - adiag[i + 1] - 1;

475:           /* decrement the offset */
476:           offset -= (nz + 1);

478:           /* first, set the diagonal elements */
479:           AjUp[offset] = (PetscInt)i;
480:           AAUp[offset] = (MatScalar)1. / v[nz];
481:           AiUp[i]      = AiUp[i + 1] - (nz + 1);

483:           PetscCall(PetscArraycpy(&AjUp[offset + 1], vi, nz));
484:           PetscCall(PetscArraycpy(&AAUp[offset + 1], v, nz));
485:         }

487:         /* allocate space for the triangular factor information */
488:         PetscCall(PetscNew(&upTriFactor));
489:         upTriFactor->solvePolicy = CUSPARSE_SOLVE_POLICY_USE_LEVEL;

491:         /* Create the matrix description */
492:         PetscCallCUSPARSE(cusparseCreateMatDescr(&upTriFactor->descr));
493:         PetscCallCUSPARSE(cusparseSetMatIndexBase(upTriFactor->descr, CUSPARSE_INDEX_BASE_ZERO));
494:   #if PETSC_PKG_CUDA_VERSION_GE(9, 0, 0)
495:         PetscCallCUSPARSE(cusparseSetMatType(upTriFactor->descr, CUSPARSE_MATRIX_TYPE_GENERAL));
496:   #else
497:         PetscCallCUSPARSE(cusparseSetMatType(upTriFactor->descr, CUSPARSE_MATRIX_TYPE_TRIANGULAR));
498:   #endif
499:         PetscCallCUSPARSE(cusparseSetMatFillMode(upTriFactor->descr, CUSPARSE_FILL_MODE_UPPER));
500:         PetscCallCUSPARSE(cusparseSetMatDiagType(upTriFactor->descr, CUSPARSE_DIAG_TYPE_NON_UNIT));

502:         /* set the operation */
503:         upTriFactor->solveOp = CUSPARSE_OPERATION_NON_TRANSPOSE;

505:         /* set the matrix */
506:         upTriFactor->csrMat              = new CsrMatrix;
507:         upTriFactor->csrMat->num_rows    = n;
508:         upTriFactor->csrMat->num_cols    = n;
509:         upTriFactor->csrMat->num_entries = nzUpper;

511:         upTriFactor->csrMat->row_offsets = new THRUSTINTARRAY32(n + 1);
512:         upTriFactor->csrMat->row_offsets->assign(AiUp, AiUp + n + 1);

514:         upTriFactor->csrMat->column_indices = new THRUSTINTARRAY32(nzUpper);
515:         upTriFactor->csrMat->column_indices->assign(AjUp, AjUp + nzUpper);

517:         upTriFactor->csrMat->values = new THRUSTARRAY(nzUpper);
518:         upTriFactor->csrMat->values->assign(AAUp, AAUp + nzUpper);

520:         /* Create the solve analysis information */
521:         PetscCall(PetscLogEventBegin(MAT_CUSPARSESolveAnalysis, A, 0, 0, 0));
522:         PetscCallCUSPARSE(cusparseCreateCsrsvInfo(&upTriFactor->solveInfo));
523:   #if PETSC_PKG_CUDA_VERSION_GE(9, 0, 0)
524:         PetscCallCUSPARSE(cusparseXcsrsv_buffsize(cusparseTriFactors->handle, upTriFactor->solveOp, upTriFactor->csrMat->num_rows, upTriFactor->csrMat->num_entries, upTriFactor->descr, upTriFactor->csrMat->values->data().get(),
525:                                                   upTriFactor->csrMat->row_offsets->data().get(), upTriFactor->csrMat->column_indices->data().get(), upTriFactor->solveInfo, &upTriFactor->solveBufferSize));
526:         PetscCallCUDA(cudaMalloc(&upTriFactor->solveBuffer, upTriFactor->solveBufferSize));
527:   #endif

529:         /* perform the solve analysis */
530:         PetscCallCUSPARSE(cusparseXcsrsv_analysis(cusparseTriFactors->handle, upTriFactor->solveOp, upTriFactor->csrMat->num_rows, upTriFactor->csrMat->num_entries, upTriFactor->descr, upTriFactor->csrMat->values->data().get(),
531:                                                   upTriFactor->csrMat->row_offsets->data().get(), upTriFactor->csrMat->column_indices->data().get(), upTriFactor->solveInfo, upTriFactor->solvePolicy, upTriFactor->solveBuffer));

533:         PetscCallCUDA(WaitForCUDA());
534:         PetscCall(PetscLogEventEnd(MAT_CUSPARSESolveAnalysis, A, 0, 0, 0));

536:         /* assign the pointer */
537:         ((Mat_SeqAIJCUSPARSETriFactors *)A->spptr)->upTriFactorPtr = upTriFactor;
538:         upTriFactor->AA_h                                          = AAUp;
539:         PetscCallCUDA(cudaFreeHost(AiUp));
540:         PetscCallCUDA(cudaFreeHost(AjUp));
541:         PetscCall(PetscLogCpuToGpu((n + 1 + nzUpper) * sizeof(int) + nzUpper * sizeof(PetscScalar)));
542:       } else {
543:         if (!upTriFactor->AA_h) PetscCallCUDA(cudaMallocHost((void **)&upTriFactor->AA_h, nzUpper * sizeof(PetscScalar)));
544:         /* Fill the upper triangular matrix */
545:         offset = nzUpper;
546:         for (i = n - 1; i >= 0; i--) {
547:           v = aa + adiag[i + 1] + 1;

549:           /* number of elements NOT on the diagonal */
550:           nz = adiag[i] - adiag[i + 1] - 1;

552:           /* decrement the offset */
553:           offset -= (nz + 1);

555:           /* first, set the diagonal elements */
556:           upTriFactor->AA_h[offset] = 1. / v[nz];
557:           PetscCall(PetscArraycpy(&upTriFactor->AA_h[offset + 1], v, nz));
558:         }
559:         upTriFactor->csrMat->values->assign(upTriFactor->AA_h, upTriFactor->AA_h + nzUpper);
560:         PetscCall(PetscLogCpuToGpu(nzUpper * sizeof(PetscScalar)));
561:       }
562:     } catch (char *ex) {
563:       SETERRQ(PETSC_COMM_SELF, PETSC_ERR_LIB, "CUSPARSE error: %s", ex);
564:     }
565:   }
566:   PetscFunctionReturn(PETSC_SUCCESS);
567: }
568: #endif

570: static PetscErrorCode MatSeqAIJCUSPARSEILUAnalysisAndCopyToGPU(Mat A)
571: {
572:   Mat_SeqAIJ                   *a                  = (Mat_SeqAIJ *)A->data;
573:   Mat_SeqAIJCUSPARSETriFactors *cusparseTriFactors = (Mat_SeqAIJCUSPARSETriFactors *)A->spptr;
574:   IS                            isrow = a->row, isicol = a->icol;
575:   PetscBool                     row_identity, col_identity;
576:   PetscInt                      n = A->rmap->n;

578:   PetscFunctionBegin;
579:   PetscCheck(cusparseTriFactors, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing cusparseTriFactors");
580: #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
581:   PetscCall(MatSeqAIJCUSPARSEBuildFactoredMatrix_LU(A));
582: #else
583:   PetscCall(MatSeqAIJCUSPARSEBuildILULowerTriMatrix(A));
584:   PetscCall(MatSeqAIJCUSPARSEBuildILUUpperTriMatrix(A));
585:   if (!cusparseTriFactors->workVector) cusparseTriFactors->workVector = new THRUSTARRAY(n);
586: #endif

588:   cusparseTriFactors->nnz = a->nz;

590:   A->offloadmask = PETSC_OFFLOAD_BOTH; // factored matrix is sync'ed to GPU
591:   /* lower triangular indices */
592:   PetscCall(ISIdentity(isrow, &row_identity));
593:   if (!row_identity && !cusparseTriFactors->rpermIndices) {
594:     const PetscInt *r;

596:     PetscCall(ISGetIndices(isrow, &r));
597:     cusparseTriFactors->rpermIndices = new THRUSTINTARRAY(n);
598:     cusparseTriFactors->rpermIndices->assign(r, r + n);
599:     PetscCall(ISRestoreIndices(isrow, &r));
600:     PetscCall(PetscLogCpuToGpu(n * sizeof(PetscInt)));
601:   }

603:   /* upper triangular indices */
604:   PetscCall(ISIdentity(isicol, &col_identity));
605:   if (!col_identity && !cusparseTriFactors->cpermIndices) {
606:     const PetscInt *c;

608:     PetscCall(ISGetIndices(isicol, &c));
609:     cusparseTriFactors->cpermIndices = new THRUSTINTARRAY(n);
610:     cusparseTriFactors->cpermIndices->assign(c, c + n);
611:     PetscCall(ISRestoreIndices(isicol, &c));
612:     PetscCall(PetscLogCpuToGpu(n * sizeof(PetscInt)));
613:   }
614:   PetscFunctionReturn(PETSC_SUCCESS);
615: }

617: #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
618: static PetscErrorCode MatSeqAIJCUSPARSEBuildFactoredMatrix_Cholesky(Mat A)
619: {
620:   Mat_SeqAIJ                   *a  = static_cast<Mat_SeqAIJ *>(A->data);
621:   PetscInt                      m  = A->rmap->n;
622:   Mat_SeqAIJCUSPARSETriFactors *fs = static_cast<Mat_SeqAIJCUSPARSETriFactors *>(A->spptr);
623:   const PetscInt               *Ai = a->i, *Aj = a->j, *adiag;
624:   const MatScalar              *Aa = a->a;
625:   PetscInt                     *Mj, Mnz;
626:   PetscScalar                  *Ma, *D;

628:   PetscFunctionBegin;
629:   PetscCall(MatGetDiagonalMarkers_SeqAIJ(A, &adiag, NULL));
630:   if (A->offloadmask == PETSC_OFFLOAD_CPU) { // A's latest factors are on CPU
631:     if (!fs->csrRowPtr) {                    // Is't the first time to do the setup? Use csrRowPtr since it is not null even m=0
632:       // Re-arrange the (skewed) factored matrix and put the result into M, a regular csr matrix on host.
633:       // See comments at MatICCFactorSymbolic_SeqAIJ() on the layout of the factored matrix (U) on host.
634:       Mnz = Ai[m]; // Unz (with the unit diagonal)
635:       PetscCall(PetscMalloc1(Mnz, &Ma));
636:       PetscCall(PetscMalloc1(Mnz, &Mj)); // Mj[] is temp
637:       PetscCall(PetscMalloc1(m, &D));    // the diagonal
638:       for (PetscInt i = 0; i < m; i++) {
639:         PetscInt ulen = Ai[i + 1] - Ai[i];
640:         Mj[Ai[i]]     = i;                                              // diagonal entry
641:         PetscCall(PetscArraycpy(Mj + Ai[i] + 1, Aj + Ai[i], ulen - 1)); // entries of U on the right of the diagonal
642:       }
643:       // Copy M (U) from host to device
644:       PetscCallCUDA(cudaMalloc(&fs->csrRowPtr, sizeof(*fs->csrRowPtr) * (m + 1)));
645:       PetscCallCUDA(cudaMalloc(&fs->csrColIdx, sizeof(*fs->csrColIdx) * Mnz));
646:       PetscCallCUDA(cudaMalloc(&fs->csrVal, sizeof(*fs->csrVal) * Mnz));
647:       PetscCallCUDA(cudaMalloc(&fs->diag, sizeof(*fs->diag) * m));
648:       PetscCallCUDA(cudaMemcpy(fs->csrRowPtr, Ai, sizeof(*Ai) * (m + 1), cudaMemcpyHostToDevice));
649:       PetscCallCUDA(cudaMemcpy(fs->csrColIdx, Mj, sizeof(*Mj) * Mnz, cudaMemcpyHostToDevice));

651:       // Create descriptors for L, U. See https://docs.nvidia.com/cuda/cusparse/index.html#cusparseDiagType_t
652:       // cusparseDiagType_t: This type indicates if the matrix diagonal entries are unity. The diagonal elements are always
653:       // assumed to be present, but if CUSPARSE_DIAG_TYPE_UNIT is passed to an API routine, then the routine assumes that
654:       // all diagonal entries are unity and will not read or modify those entries. Note that in this case the routine
655:       // assumes the diagonal entries are equal to one, regardless of what those entries are actually set to in memory.
656:       cusparseFillMode_t        fillMode  = CUSPARSE_FILL_MODE_UPPER;
657:       cusparseDiagType_t        diagType  = CUSPARSE_DIAG_TYPE_UNIT; // U is unit diagonal
658:       const cusparseIndexType_t indexType = PetscDefined(USE_64BIT_INDICES) ? CUSPARSE_INDEX_64I : CUSPARSE_INDEX_32I;

660:       PetscCallCUSPARSE(cusparseCreateCsr(&fs->spMatDescr_U, m, m, Mnz, fs->csrRowPtr, fs->csrColIdx, fs->csrVal, indexType, indexType, CUSPARSE_INDEX_BASE_ZERO, cusparse_scalartype));
661:       PetscCallCUSPARSE(cusparseSpMatSetAttribute(fs->spMatDescr_U, CUSPARSE_SPMAT_FILL_MODE, &fillMode, sizeof(fillMode)));
662:       PetscCallCUSPARSE(cusparseSpMatSetAttribute(fs->spMatDescr_U, CUSPARSE_SPMAT_DIAG_TYPE, &diagType, sizeof(diagType)));

664:       // Allocate work vectors in SpSv
665:       PetscCallCUDA(cudaMalloc((void **)&fs->X, sizeof(*fs->X) * m));
666:       PetscCallCUDA(cudaMalloc((void **)&fs->Y, sizeof(*fs->Y) * m));

668:       PetscCallCUSPARSE(cusparseCreateDnVec(&fs->dnVecDescr_X, m, fs->X, cusparse_scalartype));
669:       PetscCallCUSPARSE(cusparseCreateDnVec(&fs->dnVecDescr_Y, m, fs->Y, cusparse_scalartype));

671:       // Query buffer sizes for SpSV and then allocate buffers
672:       PetscCallCUSPARSE(cusparseSpSV_createDescr(&fs->spsvDescr_U));
673:       PetscCallCUSPARSE(cusparseSpSV_bufferSize(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_U, &fs->spsvBufferSize_U));
674:       PetscCallCUDA(cudaMalloc((void **)&fs->spsvBuffer_U, fs->spsvBufferSize_U));

676:       PetscCallCUSPARSE(cusparseSpSV_createDescr(&fs->spsvDescr_Ut)); // Ut solve uses the same matrix (spMatDescr_U), but different descr and buffer
677:       PetscCallCUSPARSE(cusparseSpSV_bufferSize(fs->handle, CUSPARSE_OPERATION_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_Ut, &fs->spsvBufferSize_Ut));
678:       PetscCallCUDA(cudaMalloc((void **)&fs->spsvBuffer_Ut, fs->spsvBufferSize_Ut));

680:       // Record for reuse
681:       fs->csrVal_h = Ma;
682:       fs->diag_h   = D;
683:       PetscCall(PetscFree(Mj));
684:     }
685:     // Copy the value
686:     Ma  = fs->csrVal_h;
687:     D   = fs->diag_h;
688:     Mnz = Ai[m];
689:     for (PetscInt i = 0; i < m; i++) {
690:       D[i]      = Aa[adiag[i]];   // actually Aa[adiag[i]] is the inverse of the diagonal
691:       Ma[Ai[i]] = (MatScalar)1.0; // set the unit diagonal, which is cosmetic since cusparse does not really read it given CUSPARSE_DIAG_TYPE_UNIT
692:       for (PetscInt k = 0; k < Ai[i + 1] - Ai[i] - 1; k++) Ma[Ai[i] + 1 + k] = -Aa[Ai[i] + k];
693:     }
694:     PetscCallCUDA(cudaMemcpy(fs->csrVal, Ma, sizeof(*Ma) * Mnz, cudaMemcpyHostToDevice));
695:     PetscCallCUDA(cudaMemcpy(fs->diag, D, sizeof(*D) * m, cudaMemcpyHostToDevice));

697:   #if PETSC_PKG_CUDA_VERSION_GE(12, 1, 1)
698:     if (fs->updatedSpSVAnalysis) {
699:       if (fs->csrVal) PetscCallCUSPARSE(cusparseSpSV_updateMatrix(fs->handle, fs->spsvDescr_U, fs->csrVal, CUSPARSE_SPSV_UPDATE_GENERAL));
700:       if (fs->csrVal) PetscCallCUSPARSE(cusparseSpSV_updateMatrix(fs->handle, fs->spsvDescr_Ut, fs->csrVal, CUSPARSE_SPSV_UPDATE_GENERAL));
701:     } else
702:   #endif
703:     {
704:       // Do cusparseSpSV_analysis(), which is numeric and requires valid and up-to-date matrix values
705:       PetscCallCUSPARSE(cusparseSpSV_analysis(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_U, fs->spsvBuffer_U));
706:       PetscCallCUSPARSE(cusparseSpSV_analysis(fs->handle, CUSPARSE_OPERATION_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_Ut, fs->spsvBuffer_Ut));
707:       fs->updatedSpSVAnalysis = PETSC_TRUE;
708:     }
709:   }
710:   PetscFunctionReturn(PETSC_SUCCESS);
711: }

713: // Solve Ut D U x = b
714: static PetscErrorCode MatSolve_SeqAIJCUSPARSE_Cholesky(Mat A, Vec b, Vec x)
715: {
716:   Mat_SeqAIJCUSPARSETriFactors         *fs  = static_cast<Mat_SeqAIJCUSPARSETriFactors *>(A->spptr);
717:   Mat_SeqAIJ                           *aij = static_cast<Mat_SeqAIJ *>(A->data);
718:   const PetscScalar                    *barray;
719:   PetscScalar                          *xarray;
720:   thrust::device_ptr<const PetscScalar> bGPU;
721:   thrust::device_ptr<PetscScalar>       xGPU;
722:   const cusparseSpSVAlg_t               alg = CUSPARSE_SPSV_ALG_DEFAULT;
723:   PetscInt                              m   = A->rmap->n;

725:   PetscFunctionBegin;
726:   PetscCall(PetscLogGpuTimeBegin());
727:   PetscCall(VecCUDAGetArrayWrite(x, &xarray));
728:   PetscCall(VecCUDAGetArrayRead(b, &barray));
729:   xGPU = thrust::device_pointer_cast(xarray);
730:   bGPU = thrust::device_pointer_cast(barray);

732:   // Reorder b with the row permutation if needed, and wrap the result in fs->X
733:   if (fs->rpermIndices) {
734:     PetscCallThrust(thrust::copy(thrust::cuda::par.on(PetscDefaultCudaStream), thrust::make_permutation_iterator(bGPU, fs->rpermIndices->begin()), thrust::make_permutation_iterator(bGPU, fs->rpermIndices->end()), thrust::device_pointer_cast(fs->X)));
735:     PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, fs->X));
736:   } else {
737:     PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, (void *)barray));
738:   }

740:   // Solve Ut Y = X
741:   PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_Y, fs->Y));
742:   PetscCallCUSPARSE(cusparseSpSV_solve(fs->handle, CUSPARSE_OPERATION_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, alg, fs->spsvDescr_Ut));

744:   // Solve diag(D) Z = Y. Actually just do Y = Y*D since D is already inverted in MatCholeskyFactorNumeric_SeqAIJ().
745:   // It is basically a vector element-wise multiplication, but cublas does not have it!
746:   PetscCallThrust(thrust::transform(thrust::cuda::par.on(PetscDefaultCudaStream), thrust::device_pointer_cast(fs->Y), thrust::device_pointer_cast(fs->Y + m), thrust::device_pointer_cast(fs->diag), thrust::device_pointer_cast(fs->Y), thrust::multiplies<PetscScalar>()));

748:   // Solve U X = Y
749:   if (fs->cpermIndices) { // if need to permute, we need to use the intermediate buffer X
750:     PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, fs->X));
751:   } else {
752:     PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, xarray));
753:   }
754:   PetscCallCUSPARSE(cusparseSpSV_solve(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_Y, fs->dnVecDescr_X, cusparse_scalartype, alg, fs->spsvDescr_U));

756:   // Reorder X with the column permutation if needed, and put the result back to x
757:   if (fs->cpermIndices) {
758:     PetscCallThrust(thrust::copy(thrust::cuda::par.on(PetscDefaultCudaStream), thrust::make_permutation_iterator(thrust::device_pointer_cast(fs->X), fs->cpermIndices->begin()),
759:                                  thrust::make_permutation_iterator(thrust::device_pointer_cast(fs->X + m), fs->cpermIndices->end()), xGPU));
760:   }

762:   PetscCall(VecCUDARestoreArrayRead(b, &barray));
763:   PetscCall(VecCUDARestoreArrayWrite(x, &xarray));
764:   PetscCall(PetscLogGpuTimeEnd());
765:   PetscCall(PetscLogGpuFlops(4.0 * aij->nz - A->rmap->n));
766:   PetscFunctionReturn(PETSC_SUCCESS);
767: }
768: #else
769: static PetscErrorCode MatSeqAIJCUSPARSEBuildICCTriMatrices(Mat A)
770: {
771:   Mat_SeqAIJ                        *a                  = (Mat_SeqAIJ *)A->data;
772:   Mat_SeqAIJCUSPARSETriFactors      *cusparseTriFactors = (Mat_SeqAIJCUSPARSETriFactors *)A->spptr;
773:   Mat_SeqAIJCUSPARSETriFactorStruct *loTriFactor        = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->loTriFactorPtr;
774:   Mat_SeqAIJCUSPARSETriFactorStruct *upTriFactor        = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->upTriFactorPtr;
775:   PetscInt                          *AiUp, *AjUp;
776:   PetscScalar                       *AAUp;
777:   PetscScalar                       *AALo;
778:   PetscInt                           nzUpper = a->nz, n = A->rmap->n, i, offset, nz, j;
779:   Mat_SeqSBAIJ                      *b  = (Mat_SeqSBAIJ *)A->data;
780:   const PetscInt                    *ai = b->i, *aj = b->j, *vj;
781:   const MatScalar                   *aa = b->a, *v;

783:   PetscFunctionBegin;
784:   if (!n) PetscFunctionReturn(PETSC_SUCCESS);
785:   if (A->offloadmask == PETSC_OFFLOAD_UNALLOCATED || A->offloadmask == PETSC_OFFLOAD_CPU) {
786:     try {
787:       PetscCallCUDA(cudaMallocHost((void **)&AAUp, nzUpper * sizeof(PetscScalar)));
788:       PetscCallCUDA(cudaMallocHost((void **)&AALo, nzUpper * sizeof(PetscScalar)));
789:       if (!upTriFactor && !loTriFactor) {
790:         /* Allocate Space for the upper triangular matrix */
791:         PetscCallCUDA(cudaMallocHost((void **)&AiUp, (n + 1) * sizeof(PetscInt)));
792:         PetscCallCUDA(cudaMallocHost((void **)&AjUp, nzUpper * sizeof(PetscInt)));

794:         /* Fill the upper triangular matrix */
795:         AiUp[0] = (PetscInt)0;
796:         AiUp[n] = nzUpper;
797:         offset  = 0;
798:         for (i = 0; i < n; i++) {
799:           /* set the pointers */
800:           v  = aa + ai[i];
801:           vj = aj + ai[i];
802:           nz = ai[i + 1] - ai[i] - 1; /* exclude diag[i] */

804:           /* first, set the diagonal elements */
805:           AjUp[offset] = (PetscInt)i;
806:           AAUp[offset] = (MatScalar)1.0 / v[nz];
807:           AiUp[i]      = offset;
808:           AALo[offset] = (MatScalar)1.0 / v[nz];

810:           offset += 1;
811:           if (nz > 0) {
812:             PetscCall(PetscArraycpy(&AjUp[offset], vj, nz));
813:             PetscCall(PetscArraycpy(&AAUp[offset], v, nz));
814:             for (j = offset; j < offset + nz; j++) {
815:               AAUp[j] = -AAUp[j];
816:               AALo[j] = AAUp[j] / v[nz];
817:             }
818:             offset += nz;
819:           }
820:         }

822:         /* allocate space for the triangular factor information */
823:         PetscCall(PetscNew(&upTriFactor));
824:         upTriFactor->solvePolicy = CUSPARSE_SOLVE_POLICY_USE_LEVEL;

826:         /* Create the matrix description */
827:         PetscCallCUSPARSE(cusparseCreateMatDescr(&upTriFactor->descr));
828:         PetscCallCUSPARSE(cusparseSetMatIndexBase(upTriFactor->descr, CUSPARSE_INDEX_BASE_ZERO));
829:   #if PETSC_PKG_CUDA_VERSION_GE(9, 0, 0)
830:         PetscCallCUSPARSE(cusparseSetMatType(upTriFactor->descr, CUSPARSE_MATRIX_TYPE_GENERAL));
831:   #else
832:         PetscCallCUSPARSE(cusparseSetMatType(upTriFactor->descr, CUSPARSE_MATRIX_TYPE_TRIANGULAR));
833:   #endif
834:         PetscCallCUSPARSE(cusparseSetMatFillMode(upTriFactor->descr, CUSPARSE_FILL_MODE_UPPER));
835:         PetscCallCUSPARSE(cusparseSetMatDiagType(upTriFactor->descr, CUSPARSE_DIAG_TYPE_UNIT));

837:         /* set the matrix */
838:         upTriFactor->csrMat              = new CsrMatrix;
839:         upTriFactor->csrMat->num_rows    = A->rmap->n;
840:         upTriFactor->csrMat->num_cols    = A->cmap->n;
841:         upTriFactor->csrMat->num_entries = a->nz;

843:         upTriFactor->csrMat->row_offsets = new THRUSTINTARRAY32(A->rmap->n + 1);
844:         upTriFactor->csrMat->row_offsets->assign(AiUp, AiUp + A->rmap->n + 1);

846:         upTriFactor->csrMat->column_indices = new THRUSTINTARRAY32(a->nz);
847:         upTriFactor->csrMat->column_indices->assign(AjUp, AjUp + a->nz);

849:         upTriFactor->csrMat->values = new THRUSTARRAY(a->nz);
850:         upTriFactor->csrMat->values->assign(AAUp, AAUp + a->nz);

852:         /* set the operation */
853:         upTriFactor->solveOp = CUSPARSE_OPERATION_NON_TRANSPOSE;

855:         /* Create the solve analysis information */
856:         PetscCall(PetscLogEventBegin(MAT_CUSPARSESolveAnalysis, A, 0, 0, 0));
857:         PetscCallCUSPARSE(cusparseCreateCsrsvInfo(&upTriFactor->solveInfo));
858:   #if PETSC_PKG_CUDA_VERSION_GE(9, 0, 0)
859:         PetscCallCUSPARSE(cusparseXcsrsv_buffsize(cusparseTriFactors->handle, upTriFactor->solveOp, upTriFactor->csrMat->num_rows, upTriFactor->csrMat->num_entries, upTriFactor->descr, upTriFactor->csrMat->values->data().get(),
860:                                                   upTriFactor->csrMat->row_offsets->data().get(), upTriFactor->csrMat->column_indices->data().get(), upTriFactor->solveInfo, &upTriFactor->solveBufferSize));
861:         PetscCallCUDA(cudaMalloc(&upTriFactor->solveBuffer, upTriFactor->solveBufferSize));
862:   #endif

864:         /* perform the solve analysis */
865:         PetscCallCUSPARSE(cusparseXcsrsv_analysis(cusparseTriFactors->handle, upTriFactor->solveOp, upTriFactor->csrMat->num_rows, upTriFactor->csrMat->num_entries, upTriFactor->descr, upTriFactor->csrMat->values->data().get(),
866:                                                   upTriFactor->csrMat->row_offsets->data().get(), upTriFactor->csrMat->column_indices->data().get(), upTriFactor->solveInfo, upTriFactor->solvePolicy, upTriFactor->solveBuffer));

868:         PetscCallCUDA(WaitForCUDA());
869:         PetscCall(PetscLogEventEnd(MAT_CUSPARSESolveAnalysis, A, 0, 0, 0));

871:         /* assign the pointer */
872:         ((Mat_SeqAIJCUSPARSETriFactors *)A->spptr)->upTriFactorPtr = upTriFactor;

874:         /* allocate space for the triangular factor information */
875:         PetscCall(PetscNew(&loTriFactor));
876:         loTriFactor->solvePolicy = CUSPARSE_SOLVE_POLICY_USE_LEVEL;

878:         /* Create the matrix description */
879:         PetscCallCUSPARSE(cusparseCreateMatDescr(&loTriFactor->descr));
880:         PetscCallCUSPARSE(cusparseSetMatIndexBase(loTriFactor->descr, CUSPARSE_INDEX_BASE_ZERO));
881:   #if PETSC_PKG_CUDA_VERSION_GE(9, 0, 0)
882:         PetscCallCUSPARSE(cusparseSetMatType(loTriFactor->descr, CUSPARSE_MATRIX_TYPE_GENERAL));
883:   #else
884:         PetscCallCUSPARSE(cusparseSetMatType(loTriFactor->descr, CUSPARSE_MATRIX_TYPE_TRIANGULAR));
885:   #endif
886:         PetscCallCUSPARSE(cusparseSetMatFillMode(loTriFactor->descr, CUSPARSE_FILL_MODE_UPPER));
887:         PetscCallCUSPARSE(cusparseSetMatDiagType(loTriFactor->descr, CUSPARSE_DIAG_TYPE_NON_UNIT));

889:         /* set the operation */
890:         loTriFactor->solveOp = CUSPARSE_OPERATION_TRANSPOSE;

892:         /* set the matrix */
893:         loTriFactor->csrMat              = new CsrMatrix;
894:         loTriFactor->csrMat->num_rows    = A->rmap->n;
895:         loTriFactor->csrMat->num_cols    = A->cmap->n;
896:         loTriFactor->csrMat->num_entries = a->nz;

898:         loTriFactor->csrMat->row_offsets = new THRUSTINTARRAY32(A->rmap->n + 1);
899:         loTriFactor->csrMat->row_offsets->assign(AiUp, AiUp + A->rmap->n + 1);

901:         loTriFactor->csrMat->column_indices = new THRUSTINTARRAY32(a->nz);
902:         loTriFactor->csrMat->column_indices->assign(AjUp, AjUp + a->nz);

904:         loTriFactor->csrMat->values = new THRUSTARRAY(a->nz);
905:         loTriFactor->csrMat->values->assign(AALo, AALo + a->nz);

907:         /* Create the solve analysis information */
908:         PetscCall(PetscLogEventBegin(MAT_CUSPARSESolveAnalysis, A, 0, 0, 0));
909:         PetscCallCUSPARSE(cusparseCreateCsrsvInfo(&loTriFactor->solveInfo));
910:   #if PETSC_PKG_CUDA_VERSION_GE(9, 0, 0)
911:         PetscCallCUSPARSE(cusparseXcsrsv_buffsize(cusparseTriFactors->handle, loTriFactor->solveOp, loTriFactor->csrMat->num_rows, loTriFactor->csrMat->num_entries, loTriFactor->descr, loTriFactor->csrMat->values->data().get(),
912:                                                   loTriFactor->csrMat->row_offsets->data().get(), loTriFactor->csrMat->column_indices->data().get(), loTriFactor->solveInfo, &loTriFactor->solveBufferSize));
913:         PetscCallCUDA(cudaMalloc(&loTriFactor->solveBuffer, loTriFactor->solveBufferSize));
914:   #endif

916:         /* perform the solve analysis */
917:         PetscCallCUSPARSE(cusparseXcsrsv_analysis(cusparseTriFactors->handle, loTriFactor->solveOp, loTriFactor->csrMat->num_rows, loTriFactor->csrMat->num_entries, loTriFactor->descr, loTriFactor->csrMat->values->data().get(),
918:                                                   loTriFactor->csrMat->row_offsets->data().get(), loTriFactor->csrMat->column_indices->data().get(), loTriFactor->solveInfo, loTriFactor->solvePolicy, loTriFactor->solveBuffer));

920:         PetscCallCUDA(WaitForCUDA());
921:         PetscCall(PetscLogEventEnd(MAT_CUSPARSESolveAnalysis, A, 0, 0, 0));

923:         /* assign the pointer */
924:         ((Mat_SeqAIJCUSPARSETriFactors *)A->spptr)->loTriFactorPtr = loTriFactor;

926:         PetscCall(PetscLogCpuToGpu(2 * (((A->rmap->n + 1) + (a->nz)) * sizeof(int) + (a->nz) * sizeof(PetscScalar))));
927:         PetscCallCUDA(cudaFreeHost(AiUp));
928:         PetscCallCUDA(cudaFreeHost(AjUp));
929:       } else {
930:         /* Fill the upper triangular matrix */
931:         offset = 0;
932:         for (i = 0; i < n; i++) {
933:           /* set the pointers */
934:           v  = aa + ai[i];
935:           nz = ai[i + 1] - ai[i] - 1; /* exclude diag[i] */

937:           /* first, set the diagonal elements */
938:           AAUp[offset] = 1.0 / v[nz];
939:           AALo[offset] = 1.0 / v[nz];

941:           offset += 1;
942:           if (nz > 0) {
943:             PetscCall(PetscArraycpy(&AAUp[offset], v, nz));
944:             for (j = offset; j < offset + nz; j++) {
945:               AAUp[j] = -AAUp[j];
946:               AALo[j] = AAUp[j] / v[nz];
947:             }
948:             offset += nz;
949:           }
950:         }
951:         PetscCheck(upTriFactor, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing cusparseTriFactors");
952:         PetscCheck(loTriFactor, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing cusparseTriFactors");
953:         upTriFactor->csrMat->values->assign(AAUp, AAUp + a->nz);
954:         loTriFactor->csrMat->values->assign(AALo, AALo + a->nz);
955:         PetscCall(PetscLogCpuToGpu(2 * (a->nz) * sizeof(PetscScalar)));
956:       }
957:       PetscCallCUDA(cudaFreeHost(AAUp));
958:       PetscCallCUDA(cudaFreeHost(AALo));
959:     } catch (char *ex) {
960:       SETERRQ(PETSC_COMM_SELF, PETSC_ERR_LIB, "CUSPARSE error: %s", ex);
961:     }
962:   }
963:   PetscFunctionReturn(PETSC_SUCCESS);
964: }
965: #endif

967: static PetscErrorCode MatSeqAIJCUSPARSEICCAnalysisAndCopyToGPU(Mat A)
968: {
969:   Mat_SeqAIJ                   *a                  = (Mat_SeqAIJ *)A->data;
970:   Mat_SeqAIJCUSPARSETriFactors *cusparseTriFactors = (Mat_SeqAIJCUSPARSETriFactors *)A->spptr;
971:   IS                            ip                 = a->row;
972:   PetscBool                     perm_identity;
973:   PetscInt                      n = A->rmap->n;

975:   PetscFunctionBegin;
976:   PetscCheck(cusparseTriFactors, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing cusparseTriFactors");

978: #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
979:   PetscCall(MatSeqAIJCUSPARSEBuildFactoredMatrix_Cholesky(A));
980: #else
981:   PetscCall(MatSeqAIJCUSPARSEBuildICCTriMatrices(A));
982:   if (!cusparseTriFactors->workVector) cusparseTriFactors->workVector = new THRUSTARRAY(n);
983: #endif
984:   cusparseTriFactors->nnz = (a->nz - n) * 2 + n;

986:   A->offloadmask = PETSC_OFFLOAD_BOTH;

988:   /* lower triangular indices */
989:   PetscCall(ISIdentity(ip, &perm_identity));
990:   if (!perm_identity) {
991:     IS              iip;
992:     const PetscInt *irip, *rip;

994:     PetscCall(ISInvertPermutation(ip, PETSC_DECIDE, &iip));
995:     PetscCall(ISGetIndices(iip, &irip));
996:     PetscCall(ISGetIndices(ip, &rip));
997:     cusparseTriFactors->rpermIndices = new THRUSTINTARRAY(n);
998:     cusparseTriFactors->rpermIndices->assign(rip, rip + n);
999:     cusparseTriFactors->cpermIndices = new THRUSTINTARRAY(n);
1000:     cusparseTriFactors->cpermIndices->assign(irip, irip + n);
1001:     PetscCall(ISRestoreIndices(iip, &irip));
1002:     PetscCall(ISDestroy(&iip));
1003:     PetscCall(ISRestoreIndices(ip, &rip));
1004:     PetscCall(PetscLogCpuToGpu(2. * n * sizeof(PetscInt)));
1005:   }
1006:   PetscFunctionReturn(PETSC_SUCCESS);
1007: }

1009: static PetscErrorCode MatCholeskyFactorNumeric_SeqAIJCUSPARSE(Mat B, Mat A, const MatFactorInfo *info)
1010: {
1011:   PetscFunctionBegin;
1012:   PetscCall(MatSeqAIJCUSPARSECopyFromGPU(A));
1013:   PetscCall(MatCholeskyFactorNumeric_SeqAIJ(B, A, info));
1014:   B->offloadmask = PETSC_OFFLOAD_CPU;

1016: #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
1017:   B->ops->solve          = MatSolve_SeqAIJCUSPARSE_Cholesky;
1018:   B->ops->solvetranspose = MatSolve_SeqAIJCUSPARSE_Cholesky;
1019: #else
1020:   /* determine which version of MatSolve needs to be used. */
1021:   Mat_SeqAIJ *b  = (Mat_SeqAIJ *)B->data;
1022:   IS          ip = b->row;
1023:   PetscBool   perm_identity;

1025:   PetscCall(ISIdentity(ip, &perm_identity));
1026:   if (perm_identity) {
1027:     B->ops->solve          = MatSolve_SeqAIJCUSPARSE_NaturalOrdering;
1028:     B->ops->solvetranspose = MatSolveTranspose_SeqAIJCUSPARSE_NaturalOrdering;
1029:   } else {
1030:     B->ops->solve          = MatSolve_SeqAIJCUSPARSE;
1031:     B->ops->solvetranspose = MatSolveTranspose_SeqAIJCUSPARSE;
1032:   }
1033: #endif
1034:   B->ops->matsolve          = NULL;
1035:   B->ops->matsolvetranspose = NULL;

1037:   /* get the triangular factors */
1038:   PetscCall(MatSeqAIJCUSPARSEICCAnalysisAndCopyToGPU(B));
1039:   PetscFunctionReturn(PETSC_SUCCESS);
1040: }

1042: #if PETSC_PKG_CUDA_VERSION_LT(11, 4, 0)
1043: static PetscErrorCode MatSeqAIJCUSPARSEAnalyzeTransposeForSolve(Mat A)
1044: {
1045:   Mat_SeqAIJCUSPARSETriFactors      *cusparseTriFactors = (Mat_SeqAIJCUSPARSETriFactors *)A->spptr;
1046:   Mat_SeqAIJCUSPARSETriFactorStruct *loTriFactor        = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->loTriFactorPtr;
1047:   Mat_SeqAIJCUSPARSETriFactorStruct *upTriFactor        = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->upTriFactorPtr;
1048:   Mat_SeqAIJCUSPARSETriFactorStruct *loTriFactorT;
1049:   Mat_SeqAIJCUSPARSETriFactorStruct *upTriFactorT;
1050:   cusparseIndexBase_t                indexBase;
1051:   cusparseMatrixType_t               matrixType;
1052:   cusparseFillMode_t                 fillMode;
1053:   cusparseDiagType_t                 diagType;

1055:   PetscFunctionBegin;
1056:   /* allocate space for the transpose of the lower triangular factor */
1057:   PetscCall(PetscNew(&loTriFactorT));
1058:   loTriFactorT->solvePolicy = CUSPARSE_SOLVE_POLICY_USE_LEVEL;

1060:   /* set the matrix descriptors of the lower triangular factor */
1061:   matrixType = cusparseGetMatType(loTriFactor->descr);
1062:   indexBase  = cusparseGetMatIndexBase(loTriFactor->descr);
1063:   fillMode   = cusparseGetMatFillMode(loTriFactor->descr) == CUSPARSE_FILL_MODE_UPPER ? CUSPARSE_FILL_MODE_LOWER : CUSPARSE_FILL_MODE_UPPER;
1064:   diagType   = cusparseGetMatDiagType(loTriFactor->descr);

1066:   /* Create the matrix description */
1067:   PetscCallCUSPARSE(cusparseCreateMatDescr(&loTriFactorT->descr));
1068:   PetscCallCUSPARSE(cusparseSetMatIndexBase(loTriFactorT->descr, indexBase));
1069:   PetscCallCUSPARSE(cusparseSetMatType(loTriFactorT->descr, matrixType));
1070:   PetscCallCUSPARSE(cusparseSetMatFillMode(loTriFactorT->descr, fillMode));
1071:   PetscCallCUSPARSE(cusparseSetMatDiagType(loTriFactorT->descr, diagType));

1073:   /* set the operation */
1074:   loTriFactorT->solveOp = CUSPARSE_OPERATION_NON_TRANSPOSE;

1076:   /* allocate GPU space for the CSC of the lower triangular factor*/
1077:   loTriFactorT->csrMat                 = new CsrMatrix;
1078:   loTriFactorT->csrMat->num_rows       = loTriFactor->csrMat->num_cols;
1079:   loTriFactorT->csrMat->num_cols       = loTriFactor->csrMat->num_rows;
1080:   loTriFactorT->csrMat->num_entries    = loTriFactor->csrMat->num_entries;
1081:   loTriFactorT->csrMat->row_offsets    = new THRUSTINTARRAY32(loTriFactorT->csrMat->num_rows + 1);
1082:   loTriFactorT->csrMat->column_indices = new THRUSTINTARRAY32(loTriFactorT->csrMat->num_entries);
1083:   loTriFactorT->csrMat->values         = new THRUSTARRAY(loTriFactorT->csrMat->num_entries);

1085:   /* compute the transpose of the lower triangular factor, i.e. the CSC */
1086:   #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
1087:   PetscCallCUSPARSE(cusparseCsr2cscEx2_bufferSize(cusparseTriFactors->handle, loTriFactor->csrMat->num_rows, loTriFactor->csrMat->num_cols, loTriFactor->csrMat->num_entries, loTriFactor->csrMat->values->data().get(),
1088:                                                   loTriFactor->csrMat->row_offsets->data().get(), loTriFactor->csrMat->column_indices->data().get(), loTriFactorT->csrMat->values->data().get(), loTriFactorT->csrMat->row_offsets->data().get(),
1089:                                                   loTriFactorT->csrMat->column_indices->data().get(), cusparse_scalartype, CUSPARSE_ACTION_NUMERIC, indexBase, CUSPARSE_CSR2CSC_ALG1, &loTriFactor->csr2cscBufferSize));
1090:   PetscCallCUDA(cudaMalloc(&loTriFactor->csr2cscBuffer, loTriFactor->csr2cscBufferSize));
1091:   #endif

1093:   PetscCall(PetscLogEventBegin(MAT_CUSPARSEGenerateTranspose, A, 0, 0, 0));
1094:   {
1095:     // there is no clean way to have PetscCallCUSPARSE wrapping this function...
1096:     auto stat = cusparse_csr2csc(cusparseTriFactors->handle, loTriFactor->csrMat->num_rows, loTriFactor->csrMat->num_cols, loTriFactor->csrMat->num_entries, loTriFactor->csrMat->values->data().get(), loTriFactor->csrMat->row_offsets->data().get(),
1097:                                  loTriFactor->csrMat->column_indices->data().get(), loTriFactorT->csrMat->values->data().get(),
1098:   #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
1099:                                  loTriFactorT->csrMat->row_offsets->data().get(), loTriFactorT->csrMat->column_indices->data().get(), cusparse_scalartype, CUSPARSE_ACTION_NUMERIC, indexBase, CUSPARSE_CSR2CSC_ALG1, loTriFactor->csr2cscBuffer);
1100:   #else
1101:                                  loTriFactorT->csrMat->column_indices->data().get(), loTriFactorT->csrMat->row_offsets->data().get(), CUSPARSE_ACTION_NUMERIC, indexBase);
1102:   #endif
1103:     PetscCallCUSPARSE(stat);
1104:   }

1106:   PetscCallCUDA(WaitForCUDA());
1107:   PetscCall(PetscLogEventBegin(MAT_CUSPARSEGenerateTranspose, A, 0, 0, 0));

1109:   /* Create the solve analysis information */
1110:   PetscCall(PetscLogEventBegin(MAT_CUSPARSESolveAnalysis, A, 0, 0, 0));
1111:   PetscCallCUSPARSE(cusparseCreateCsrsvInfo(&loTriFactorT->solveInfo));
1112:   #if PETSC_PKG_CUDA_VERSION_GE(9, 0, 0)
1113:   PetscCallCUSPARSE(cusparseXcsrsv_buffsize(cusparseTriFactors->handle, loTriFactorT->solveOp, loTriFactorT->csrMat->num_rows, loTriFactorT->csrMat->num_entries, loTriFactorT->descr, loTriFactorT->csrMat->values->data().get(),
1114:                                             loTriFactorT->csrMat->row_offsets->data().get(), loTriFactorT->csrMat->column_indices->data().get(), loTriFactorT->solveInfo, &loTriFactorT->solveBufferSize));
1115:   PetscCallCUDA(cudaMalloc(&loTriFactorT->solveBuffer, loTriFactorT->solveBufferSize));
1116:   #endif

1118:   /* perform the solve analysis */
1119:   PetscCallCUSPARSE(cusparseXcsrsv_analysis(cusparseTriFactors->handle, loTriFactorT->solveOp, loTriFactorT->csrMat->num_rows, loTriFactorT->csrMat->num_entries, loTriFactorT->descr, loTriFactorT->csrMat->values->data().get(),
1120:                                             loTriFactorT->csrMat->row_offsets->data().get(), loTriFactorT->csrMat->column_indices->data().get(), loTriFactorT->solveInfo, loTriFactorT->solvePolicy, loTriFactorT->solveBuffer));

1122:   PetscCallCUDA(WaitForCUDA());
1123:   PetscCall(PetscLogEventEnd(MAT_CUSPARSESolveAnalysis, A, 0, 0, 0));

1125:   /* assign the pointer */
1126:   ((Mat_SeqAIJCUSPARSETriFactors *)A->spptr)->loTriFactorPtrTranspose = loTriFactorT;

1128:   /*********************************************/
1129:   /* Now the Transpose of the Upper Tri Factor */
1130:   /*********************************************/

1132:   /* allocate space for the transpose of the upper triangular factor */
1133:   PetscCall(PetscNew(&upTriFactorT));
1134:   upTriFactorT->solvePolicy = CUSPARSE_SOLVE_POLICY_USE_LEVEL;

1136:   /* set the matrix descriptors of the upper triangular factor */
1137:   matrixType = cusparseGetMatType(upTriFactor->descr);
1138:   indexBase  = cusparseGetMatIndexBase(upTriFactor->descr);
1139:   fillMode   = cusparseGetMatFillMode(upTriFactor->descr) == CUSPARSE_FILL_MODE_UPPER ? CUSPARSE_FILL_MODE_LOWER : CUSPARSE_FILL_MODE_UPPER;
1140:   diagType   = cusparseGetMatDiagType(upTriFactor->descr);

1142:   /* Create the matrix description */
1143:   PetscCallCUSPARSE(cusparseCreateMatDescr(&upTriFactorT->descr));
1144:   PetscCallCUSPARSE(cusparseSetMatIndexBase(upTriFactorT->descr, indexBase));
1145:   PetscCallCUSPARSE(cusparseSetMatType(upTriFactorT->descr, matrixType));
1146:   PetscCallCUSPARSE(cusparseSetMatFillMode(upTriFactorT->descr, fillMode));
1147:   PetscCallCUSPARSE(cusparseSetMatDiagType(upTriFactorT->descr, diagType));

1149:   /* set the operation */
1150:   upTriFactorT->solveOp = CUSPARSE_OPERATION_NON_TRANSPOSE;

1152:   /* allocate GPU space for the CSC of the upper triangular factor*/
1153:   upTriFactorT->csrMat                 = new CsrMatrix;
1154:   upTriFactorT->csrMat->num_rows       = upTriFactor->csrMat->num_cols;
1155:   upTriFactorT->csrMat->num_cols       = upTriFactor->csrMat->num_rows;
1156:   upTriFactorT->csrMat->num_entries    = upTriFactor->csrMat->num_entries;
1157:   upTriFactorT->csrMat->row_offsets    = new THRUSTINTARRAY32(upTriFactorT->csrMat->num_rows + 1);
1158:   upTriFactorT->csrMat->column_indices = new THRUSTINTARRAY32(upTriFactorT->csrMat->num_entries);
1159:   upTriFactorT->csrMat->values         = new THRUSTARRAY(upTriFactorT->csrMat->num_entries);

1161:   /* compute the transpose of the upper triangular factor, i.e. the CSC */
1162:   #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
1163:   PetscCallCUSPARSE(cusparseCsr2cscEx2_bufferSize(cusparseTriFactors->handle, upTriFactor->csrMat->num_rows, upTriFactor->csrMat->num_cols, upTriFactor->csrMat->num_entries, upTriFactor->csrMat->values->data().get(),
1164:                                                   upTriFactor->csrMat->row_offsets->data().get(), upTriFactor->csrMat->column_indices->data().get(), upTriFactorT->csrMat->values->data().get(), upTriFactorT->csrMat->row_offsets->data().get(),
1165:                                                   upTriFactorT->csrMat->column_indices->data().get(), cusparse_scalartype, CUSPARSE_ACTION_NUMERIC, indexBase, CUSPARSE_CSR2CSC_ALG1, &upTriFactor->csr2cscBufferSize));
1166:   PetscCallCUDA(cudaMalloc(&upTriFactor->csr2cscBuffer, upTriFactor->csr2cscBufferSize));
1167:   #endif

1169:   PetscCall(PetscLogEventBegin(MAT_CUSPARSEGenerateTranspose, A, 0, 0, 0));
1170:   {
1171:     // there is no clean way to have PetscCallCUSPARSE wrapping this function...
1172:     auto stat = cusparse_csr2csc(cusparseTriFactors->handle, upTriFactor->csrMat->num_rows, upTriFactor->csrMat->num_cols, upTriFactor->csrMat->num_entries, upTriFactor->csrMat->values->data().get(), upTriFactor->csrMat->row_offsets->data().get(),
1173:                                  upTriFactor->csrMat->column_indices->data().get(), upTriFactorT->csrMat->values->data().get(),
1174:   #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
1175:                                  upTriFactorT->csrMat->row_offsets->data().get(), upTriFactorT->csrMat->column_indices->data().get(), cusparse_scalartype, CUSPARSE_ACTION_NUMERIC, indexBase, CUSPARSE_CSR2CSC_ALG1, upTriFactor->csr2cscBuffer);
1176:   #else
1177:                                  upTriFactorT->csrMat->column_indices->data().get(), upTriFactorT->csrMat->row_offsets->data().get(), CUSPARSE_ACTION_NUMERIC, indexBase);
1178:   #endif
1179:     PetscCallCUSPARSE(stat);
1180:   }

1182:   PetscCallCUDA(WaitForCUDA());
1183:   PetscCall(PetscLogEventBegin(MAT_CUSPARSEGenerateTranspose, A, 0, 0, 0));

1185:   /* Create the solve analysis information */
1186:   PetscCall(PetscLogEventBegin(MAT_CUSPARSESolveAnalysis, A, 0, 0, 0));
1187:   PetscCallCUSPARSE(cusparseCreateCsrsvInfo(&upTriFactorT->solveInfo));
1188:   #if PETSC_PKG_CUDA_VERSION_GE(9, 0, 0)
1189:   PetscCallCUSPARSE(cusparseXcsrsv_buffsize(cusparseTriFactors->handle, upTriFactorT->solveOp, upTriFactorT->csrMat->num_rows, upTriFactorT->csrMat->num_entries, upTriFactorT->descr, upTriFactorT->csrMat->values->data().get(),
1190:                                             upTriFactorT->csrMat->row_offsets->data().get(), upTriFactorT->csrMat->column_indices->data().get(), upTriFactorT->solveInfo, &upTriFactorT->solveBufferSize));
1191:   PetscCallCUDA(cudaMalloc(&upTriFactorT->solveBuffer, upTriFactorT->solveBufferSize));
1192:   #endif

1194:   /* perform the solve analysis */
1195:   /* christ, would it have killed you to put this stuff in a function????????? */
1196:   PetscCallCUSPARSE(cusparseXcsrsv_analysis(cusparseTriFactors->handle, upTriFactorT->solveOp, upTriFactorT->csrMat->num_rows, upTriFactorT->csrMat->num_entries, upTriFactorT->descr, upTriFactorT->csrMat->values->data().get(),
1197:                                             upTriFactorT->csrMat->row_offsets->data().get(), upTriFactorT->csrMat->column_indices->data().get(), upTriFactorT->solveInfo, upTriFactorT->solvePolicy, upTriFactorT->solveBuffer));

1199:   PetscCallCUDA(WaitForCUDA());
1200:   PetscCall(PetscLogEventEnd(MAT_CUSPARSESolveAnalysis, A, 0, 0, 0));

1202:   /* assign the pointer */
1203:   ((Mat_SeqAIJCUSPARSETriFactors *)A->spptr)->upTriFactorPtrTranspose = upTriFactorT;
1204:   PetscFunctionReturn(PETSC_SUCCESS);
1205: }
1206: #endif

1208: struct PetscScalarToPetscInt {
1209:   __host__ __device__ PetscInt operator()(PetscScalar s) { return (PetscInt)PetscRealPart(s); }
1210: };

1212: static PetscErrorCode MatSeqAIJCUSPARSEFormExplicitTranspose(Mat A)
1213: {
1214:   Mat_SeqAIJCUSPARSE           *cusparsestruct = (Mat_SeqAIJCUSPARSE *)A->spptr;
1215:   Mat_SeqAIJCUSPARSEMultStruct *matstruct, *matstructT;
1216:   Mat_SeqAIJ                   *a = (Mat_SeqAIJ *)A->data;
1217:   cusparseStatus_t              stat;
1218:   cusparseIndexBase_t           indexBase;

1220:   PetscFunctionBegin;
1221:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));
1222:   matstruct = (Mat_SeqAIJCUSPARSEMultStruct *)cusparsestruct->mat;
1223:   PetscCheck(matstruct, PETSC_COMM_SELF, PETSC_ERR_GPU, "Missing mat struct");
1224:   matstructT = (Mat_SeqAIJCUSPARSEMultStruct *)cusparsestruct->matTranspose;
1225:   PetscCheck(!A->transupdated || matstructT, PETSC_COMM_SELF, PETSC_ERR_GPU, "Missing matTranspose struct");
1226:   if (A->transupdated) PetscFunctionReturn(PETSC_SUCCESS);
1227:   PetscCall(PetscLogEventBegin(MAT_CUSPARSEGenerateTranspose, A, 0, 0, 0));
1228:   PetscCall(PetscLogGpuTimeBegin());
1229:   if (cusparsestruct->format != MAT_CUSPARSE_CSR) PetscCall(MatSeqAIJCUSPARSEInvalidateTranspose(A, PETSC_TRUE));
1230:   if (!cusparsestruct->matTranspose) { /* create cusparse matrix */
1231:     matstructT = new Mat_SeqAIJCUSPARSEMultStruct;
1232:     PetscCallCUSPARSE(cusparseCreateMatDescr(&matstructT->descr));
1233:     indexBase = cusparseGetMatIndexBase(matstruct->descr);
1234:     PetscCallCUSPARSE(cusparseSetMatIndexBase(matstructT->descr, indexBase));
1235:     PetscCallCUSPARSE(cusparseSetMatType(matstructT->descr, CUSPARSE_MATRIX_TYPE_GENERAL));

1237:     /* set alpha and beta */
1238:     PetscCallCUDA(cudaMalloc((void **)&matstructT->alpha_one, sizeof(PetscScalar)));
1239:     PetscCallCUDA(cudaMalloc((void **)&matstructT->beta_zero, sizeof(PetscScalar)));
1240:     PetscCallCUDA(cudaMalloc((void **)&matstructT->beta_one, sizeof(PetscScalar)));
1241:     PetscCallCUDA(cudaMemcpy(matstructT->alpha_one, &PETSC_CUSPARSE_ONE, sizeof(PetscScalar), cudaMemcpyHostToDevice));
1242:     PetscCallCUDA(cudaMemcpy(matstructT->beta_zero, &PETSC_CUSPARSE_ZERO, sizeof(PetscScalar), cudaMemcpyHostToDevice));
1243:     PetscCallCUDA(cudaMemcpy(matstructT->beta_one, &PETSC_CUSPARSE_ONE, sizeof(PetscScalar), cudaMemcpyHostToDevice));

1245:     if (cusparsestruct->format == MAT_CUSPARSE_CSR) {
1246:       CsrMatrix *matrixT      = new CsrMatrix;
1247:       matstructT->mat         = matrixT;
1248:       matrixT->num_rows       = A->cmap->n;
1249:       matrixT->num_cols       = A->rmap->n;
1250:       matrixT->num_entries    = a->nz;
1251:       matrixT->row_offsets    = new THRUSTINTARRAY32(matrixT->num_rows + 1);
1252:       matrixT->column_indices = new THRUSTINTARRAY32(a->nz);
1253:       matrixT->values         = new THRUSTARRAY(a->nz);

1255:       if (!cusparsestruct->rowoffsets_gpu) cusparsestruct->rowoffsets_gpu = new THRUSTINTARRAY32(A->rmap->n + 1);
1256:       cusparsestruct->rowoffsets_gpu->assign(a->i, a->i + A->rmap->n + 1);

1258: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
1259:   #if PETSC_PKG_CUDA_VERSION_GE(11, 2, 1)
1260:       stat = cusparseCreateCsr(&matstructT->matDescr, matrixT->num_rows, matrixT->num_cols, matrixT->num_entries, matrixT->row_offsets->data().get(), matrixT->column_indices->data().get(), matrixT->values->data().get(), CUSPARSE_INDEX_32I, CUSPARSE_INDEX_32I, /* row offset, col idx type due to THRUSTINTARRAY32 */
1261:                                indexBase, cusparse_scalartype);
1262:       PetscCallCUSPARSE(stat);
1263:   #else
1264:       /* cusparse-11.x returns errors with zero-sized matrices until 11.2.1,
1265:            see https://docs.nvidia.com/cuda/cuda-toolkit-release-notes/index.html#cusparse-11.2.1

1267:            I don't know what a proper value should be for matstructT->matDescr with empty matrices, so I just set
1268:            it to NULL to blow it up if one relies on it. Per https://docs.nvidia.com/cuda/cusparse/index.html#csr2cscEx2,
1269:            when nnz = 0, matrixT->row_offsets[] should be filled with indexBase. So I also set it accordingly.
1270:         */
1271:       if (matrixT->num_entries) {
1272:         stat = cusparseCreateCsr(&matstructT->matDescr, matrixT->num_rows, matrixT->num_cols, matrixT->num_entries, matrixT->row_offsets->data().get(), matrixT->column_indices->data().get(), matrixT->values->data().get(), CUSPARSE_INDEX_32I, CUSPARSE_INDEX_32I, indexBase, cusparse_scalartype);
1273:         PetscCallCUSPARSE(stat);

1275:       } else {
1276:         matstructT->matDescr = NULL;
1277:         matrixT->row_offsets->assign(matrixT->row_offsets->size(), indexBase);
1278:       }
1279:   #endif
1280: #endif
1281:     } else if (cusparsestruct->format == MAT_CUSPARSE_ELL || cusparsestruct->format == MAT_CUSPARSE_HYB) {
1282: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
1283:       SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "MAT_CUSPARSE_ELL and MAT_CUSPARSE_HYB are not supported since CUDA-11.0");
1284: #else
1285:       CsrMatrix *temp  = new CsrMatrix;
1286:       CsrMatrix *tempT = new CsrMatrix;
1287:       /* First convert HYB to CSR */
1288:       temp->num_rows       = A->rmap->n;
1289:       temp->num_cols       = A->cmap->n;
1290:       temp->num_entries    = a->nz;
1291:       temp->row_offsets    = new THRUSTINTARRAY32(A->rmap->n + 1);
1292:       temp->column_indices = new THRUSTINTARRAY32(a->nz);
1293:       temp->values         = new THRUSTARRAY(a->nz);

1295:       stat = cusparse_hyb2csr(cusparsestruct->handle, matstruct->descr, (cusparseHybMat_t)matstruct->mat, temp->values->data().get(), temp->row_offsets->data().get(), temp->column_indices->data().get());
1296:       PetscCallCUSPARSE(stat);

1298:       /* Next, convert CSR to CSC (i.e. the matrix transpose) */
1299:       tempT->num_rows       = A->rmap->n;
1300:       tempT->num_cols       = A->cmap->n;
1301:       tempT->num_entries    = a->nz;
1302:       tempT->row_offsets    = new THRUSTINTARRAY32(A->rmap->n + 1);
1303:       tempT->column_indices = new THRUSTINTARRAY32(a->nz);
1304:       tempT->values         = new THRUSTARRAY(a->nz);

1306:       stat = cusparse_csr2csc(cusparsestruct->handle, temp->num_rows, temp->num_cols, temp->num_entries, temp->values->data().get(), temp->row_offsets->data().get(), temp->column_indices->data().get(), tempT->values->data().get(),
1307:                               tempT->column_indices->data().get(), tempT->row_offsets->data().get(), CUSPARSE_ACTION_NUMERIC, indexBase);
1308:       PetscCallCUSPARSE(stat);

1310:       /* Last, convert CSC to HYB */
1311:       cusparseHybMat_t hybMat;
1312:       PetscCallCUSPARSE(cusparseCreateHybMat(&hybMat));
1313:       cusparseHybPartition_t partition = cusparsestruct->format == MAT_CUSPARSE_ELL ? CUSPARSE_HYB_PARTITION_MAX : CUSPARSE_HYB_PARTITION_AUTO;
1314:       stat                             = cusparse_csr2hyb(cusparsestruct->handle, A->rmap->n, A->cmap->n, matstructT->descr, tempT->values->data().get(), tempT->row_offsets->data().get(), tempT->column_indices->data().get(), hybMat, 0, partition);
1315:       PetscCallCUSPARSE(stat);

1317:       /* assign the pointer */
1318:       matstructT->mat = hybMat;
1319:       A->transupdated = PETSC_TRUE;
1320:       /* delete temporaries */
1321:       if (tempT) {
1322:         if (tempT->values) delete (THRUSTARRAY *)tempT->values;
1323:         if (tempT->column_indices) delete (THRUSTINTARRAY32 *)tempT->column_indices;
1324:         if (tempT->row_offsets) delete (THRUSTINTARRAY32 *)tempT->row_offsets;
1325:         delete (CsrMatrix *)tempT;
1326:       }
1327:       if (temp) {
1328:         if (temp->values) delete (THRUSTARRAY *)temp->values;
1329:         if (temp->column_indices) delete (THRUSTINTARRAY32 *)temp->column_indices;
1330:         if (temp->row_offsets) delete (THRUSTINTARRAY32 *)temp->row_offsets;
1331:         delete (CsrMatrix *)temp;
1332:       }
1333: #endif
1334:     }
1335:   }
1336:   if (cusparsestruct->format == MAT_CUSPARSE_CSR) { /* transpose mat struct may be already present, update data */
1337:     CsrMatrix *matrix  = (CsrMatrix *)matstruct->mat;
1338:     CsrMatrix *matrixT = (CsrMatrix *)matstructT->mat;
1339:     PetscCheck(matrix, PETSC_COMM_SELF, PETSC_ERR_GPU, "Missing CsrMatrix");
1340:     PetscCheck(matrix->row_offsets, PETSC_COMM_SELF, PETSC_ERR_GPU, "Missing CsrMatrix rows");
1341:     PetscCheck(matrix->column_indices, PETSC_COMM_SELF, PETSC_ERR_GPU, "Missing CsrMatrix cols");
1342:     PetscCheck(matrix->values, PETSC_COMM_SELF, PETSC_ERR_GPU, "Missing CsrMatrix values");
1343:     PetscCheck(matrixT, PETSC_COMM_SELF, PETSC_ERR_GPU, "Missing CsrMatrixT");
1344:     PetscCheck(matrixT->row_offsets, PETSC_COMM_SELF, PETSC_ERR_GPU, "Missing CsrMatrixT rows");
1345:     PetscCheck(matrixT->column_indices, PETSC_COMM_SELF, PETSC_ERR_GPU, "Missing CsrMatrixT cols");
1346:     PetscCheck(matrixT->values, PETSC_COMM_SELF, PETSC_ERR_GPU, "Missing CsrMatrixT values");
1347:     if (!cusparsestruct->rowoffsets_gpu) { /* this may be absent when we did not construct the transpose with csr2csc */
1348:       cusparsestruct->rowoffsets_gpu = new THRUSTINTARRAY32(A->rmap->n + 1);
1349:       cusparsestruct->rowoffsets_gpu->assign(a->i, a->i + A->rmap->n + 1);
1350:       PetscCall(PetscLogCpuToGpu((A->rmap->n + 1) * sizeof(PetscInt)));
1351:     }
1352:     if (!cusparsestruct->csr2csc_i) {
1353:       THRUSTARRAY csr2csc_a(matrix->num_entries);
1354:       PetscCallThrust(thrust::sequence(thrust::device, csr2csc_a.begin(), csr2csc_a.end(), 0.0));

1356:       indexBase = cusparseGetMatIndexBase(matstruct->descr);
1357: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
1358:       void  *csr2cscBuffer;
1359:       size_t csr2cscBufferSize;
1360:       stat = cusparseCsr2cscEx2_bufferSize(cusparsestruct->handle, A->rmap->n, A->cmap->n, matrix->num_entries, matrix->values->data().get(), cusparsestruct->rowoffsets_gpu->data().get(), matrix->column_indices->data().get(), matrixT->values->data().get(),
1361:                                            matrixT->row_offsets->data().get(), matrixT->column_indices->data().get(), cusparse_scalartype, CUSPARSE_ACTION_NUMERIC, indexBase, cusparsestruct->csr2cscAlg, &csr2cscBufferSize);
1362:       PetscCallCUSPARSE(stat);
1363:       PetscCallCUDA(cudaMalloc(&csr2cscBuffer, csr2cscBufferSize));
1364: #endif

1366:       if (matrix->num_entries) {
1367:         /* When there are no nonzeros, this routine mistakenly returns CUSPARSE_STATUS_INVALID_VALUE in
1368:            mat_tests-ex62_15_mpiaijcusparse on ranks 0 and 2 with CUDA-11. But CUDA-10 is OK.
1369:            I checked every parameters and they were just fine. I have no clue why cusparse complains.

1371:            Per https://docs.nvidia.com/cuda/cusparse/index.html#csr2cscEx2, when nnz = 0, matrixT->row_offsets[]
1372:            should be filled with indexBase. So I just take a shortcut here.
1373:         */
1374:         stat = cusparse_csr2csc(cusparsestruct->handle, A->rmap->n, A->cmap->n, matrix->num_entries, csr2csc_a.data().get(), cusparsestruct->rowoffsets_gpu->data().get(), matrix->column_indices->data().get(), matrixT->values->data().get(),
1375: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
1376:                                 matrixT->row_offsets->data().get(), matrixT->column_indices->data().get(), cusparse_scalartype, CUSPARSE_ACTION_NUMERIC, indexBase, cusparsestruct->csr2cscAlg, csr2cscBuffer);
1377:         PetscCallCUSPARSE(stat);
1378: #else
1379:                                 matrixT->column_indices->data().get(), matrixT->row_offsets->data().get(), CUSPARSE_ACTION_NUMERIC, indexBase);
1380:         PetscCallCUSPARSE(stat);
1381: #endif
1382:       } else {
1383:         matrixT->row_offsets->assign(matrixT->row_offsets->size(), indexBase);
1384:       }

1386:       cusparsestruct->csr2csc_i = new THRUSTINTARRAY(matrix->num_entries);
1387:       PetscCallThrust(thrust::transform(thrust::device, matrixT->values->begin(), matrixT->values->end(), cusparsestruct->csr2csc_i->begin(), PetscScalarToPetscInt()));
1388: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
1389:       PetscCallCUDA(cudaFree(csr2cscBuffer));
1390: #endif
1391:     }
1392:     PetscCallThrust(
1393:       thrust::copy(thrust::device, thrust::make_permutation_iterator(matrix->values->begin(), cusparsestruct->csr2csc_i->begin()), thrust::make_permutation_iterator(matrix->values->begin(), cusparsestruct->csr2csc_i->end()), matrixT->values->begin()));
1394:   }
1395:   PetscCall(PetscLogGpuTimeEnd());
1396:   PetscCall(PetscLogEventEnd(MAT_CUSPARSEGenerateTranspose, A, 0, 0, 0));
1397:   /* the compressed row indices is not used for matTranspose */
1398:   matstructT->cprowIndices = NULL;
1399:   /* assign the pointer */
1400:   ((Mat_SeqAIJCUSPARSE *)A->spptr)->matTranspose = matstructT;
1401:   A->transupdated                                = PETSC_TRUE;
1402:   PetscFunctionReturn(PETSC_SUCCESS);
1403: }

1405: #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
1406: static PetscErrorCode MatSolve_SeqAIJCUSPARSE_LU(Mat A, Vec b, Vec x)
1407: {
1408:   const PetscScalar                    *barray;
1409:   PetscScalar                          *xarray;
1410:   thrust::device_ptr<const PetscScalar> bGPU;
1411:   thrust::device_ptr<PetscScalar>       xGPU;
1412:   Mat_SeqAIJCUSPARSETriFactors         *fs  = static_cast<Mat_SeqAIJCUSPARSETriFactors *>(A->spptr);
1413:   const Mat_SeqAIJ                     *aij = static_cast<Mat_SeqAIJ *>(A->data);
1414:   const cusparseOperation_t             op  = CUSPARSE_OPERATION_NON_TRANSPOSE;
1415:   const cusparseSpSVAlg_t               alg = CUSPARSE_SPSV_ALG_DEFAULT;
1416:   PetscInt                              m   = A->rmap->n;

1418:   PetscFunctionBegin;
1419:   PetscCall(PetscLogGpuTimeBegin());
1420:   PetscCall(VecCUDAGetArrayWrite(x, &xarray));
1421:   PetscCall(VecCUDAGetArrayRead(b, &barray));
1422:   xGPU = thrust::device_pointer_cast(xarray);
1423:   bGPU = thrust::device_pointer_cast(barray);

1425:   // Reorder b with the row permutation if needed, and wrap the result in fs->X
1426:   if (fs->rpermIndices) {
1427:     PetscCallThrust(thrust::copy(thrust::cuda::par.on(PetscDefaultCudaStream), thrust::make_permutation_iterator(bGPU, fs->rpermIndices->begin()), thrust::make_permutation_iterator(bGPU, fs->rpermIndices->end()), thrust::device_pointer_cast(fs->X)));
1428:     PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, fs->X));
1429:   } else {
1430:     PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, (void *)barray));
1431:   }

1433:   // Solve L Y = X
1434:   PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_Y, fs->Y));
1435:   // Note that cusparseSpSV_solve() secretly uses the external buffer used in cusparseSpSV_analysis()!
1436:   PetscCallCUSPARSE(cusparseSpSV_solve(fs->handle, op, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, alg, fs->spsvDescr_L));

1438:   // Solve U X = Y
1439:   if (fs->cpermIndices) {
1440:     PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, fs->X));
1441:   } else {
1442:     PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, xarray));
1443:   }
1444:   PetscCallCUSPARSE(cusparseSpSV_solve(fs->handle, op, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_Y, fs->dnVecDescr_X, cusparse_scalartype, alg, fs->spsvDescr_U));

1446:   // Reorder X with the column permutation if needed, and put the result back to x
1447:   if (fs->cpermIndices) {
1448:     PetscCallThrust(thrust::copy(thrust::cuda::par.on(PetscDefaultCudaStream), thrust::make_permutation_iterator(thrust::device_pointer_cast(fs->X), fs->cpermIndices->begin()),
1449:                                  thrust::make_permutation_iterator(thrust::device_pointer_cast(fs->X + m), fs->cpermIndices->end()), xGPU));
1450:   }
1451:   PetscCall(VecCUDARestoreArrayRead(b, &barray));
1452:   PetscCall(VecCUDARestoreArrayWrite(x, &xarray));
1453:   PetscCall(PetscLogGpuTimeEnd());
1454:   PetscCall(PetscLogGpuFlops(2.0 * aij->nz - m));
1455:   PetscFunctionReturn(PETSC_SUCCESS);
1456: }

1458: static PetscErrorCode MatSolveTranspose_SeqAIJCUSPARSE_LU(Mat A, Vec b, Vec x)
1459: {
1460:   Mat_SeqAIJCUSPARSETriFactors         *fs  = static_cast<Mat_SeqAIJCUSPARSETriFactors *>(A->spptr);
1461:   Mat_SeqAIJ                           *aij = static_cast<Mat_SeqAIJ *>(A->data);
1462:   const PetscScalar                    *barray;
1463:   PetscScalar                          *xarray;
1464:   thrust::device_ptr<const PetscScalar> bGPU;
1465:   thrust::device_ptr<PetscScalar>       xGPU;
1466:   const cusparseOperation_t             opA = CUSPARSE_OPERATION_TRANSPOSE;
1467:   const cusparseSpSVAlg_t               alg = CUSPARSE_SPSV_ALG_DEFAULT;
1468:   PetscInt                              m   = A->rmap->n;

1470:   PetscFunctionBegin;
1471:   PetscCall(PetscLogGpuTimeBegin());
1472:   if (!fs->createdTransposeSpSVDescr) { // Call MatSolveTranspose() for the first time
1473:     PetscCallCUSPARSE(cusparseSpSV_createDescr(&fs->spsvDescr_Lt));
1474:     PetscCallCUSPARSE(cusparseSpSV_bufferSize(fs->handle, opA, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, /* The matrix is still L. We only do transpose solve with it */
1475:                                               fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, alg, fs->spsvDescr_Lt, &fs->spsvBufferSize_Lt));

1477:     PetscCallCUSPARSE(cusparseSpSV_createDescr(&fs->spsvDescr_Ut));
1478:     PetscCallCUSPARSE(cusparseSpSV_bufferSize(fs->handle, opA, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, alg, fs->spsvDescr_Ut, &fs->spsvBufferSize_Ut));
1479:     PetscCallCUDA(cudaMalloc((void **)&fs->spsvBuffer_Lt, fs->spsvBufferSize_Lt));
1480:     PetscCallCUDA(cudaMalloc((void **)&fs->spsvBuffer_Ut, fs->spsvBufferSize_Ut));
1481:     fs->createdTransposeSpSVDescr = PETSC_TRUE;
1482:   }

1484:   if (!fs->updatedTransposeSpSVAnalysis) {
1485:     PetscCallCUSPARSE(cusparseSpSV_analysis(fs->handle, opA, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, alg, fs->spsvDescr_Lt, fs->spsvBuffer_Lt));

1487:     PetscCallCUSPARSE(cusparseSpSV_analysis(fs->handle, opA, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, alg, fs->spsvDescr_Ut, fs->spsvBuffer_Ut));
1488:     fs->updatedTransposeSpSVAnalysis = PETSC_TRUE;
1489:   }

1491:   PetscCall(VecCUDAGetArrayWrite(x, &xarray));
1492:   PetscCall(VecCUDAGetArrayRead(b, &barray));
1493:   xGPU = thrust::device_pointer_cast(xarray);
1494:   bGPU = thrust::device_pointer_cast(barray);

1496:   // Reorder b with the row permutation if needed, and wrap the result in fs->X
1497:   if (fs->rpermIndices) {
1498:     PetscCallThrust(thrust::copy(thrust::cuda::par.on(PetscDefaultCudaStream), thrust::make_permutation_iterator(bGPU, fs->rpermIndices->begin()), thrust::make_permutation_iterator(bGPU, fs->rpermIndices->end()), thrust::device_pointer_cast(fs->X)));
1499:     PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, fs->X));
1500:   } else {
1501:     PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, (void *)barray));
1502:   }

1504:   // Solve Ut Y = X
1505:   PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_Y, fs->Y));
1506:   PetscCallCUSPARSE(cusparseSpSV_solve(fs->handle, opA, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, alg, fs->spsvDescr_Ut));

1508:   // Solve Lt X = Y
1509:   if (fs->cpermIndices) { // if need to permute, we need to use the intermediate buffer X
1510:     PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, fs->X));
1511:   } else {
1512:     PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, xarray));
1513:   }
1514:   PetscCallCUSPARSE(cusparseSpSV_solve(fs->handle, opA, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, fs->dnVecDescr_Y, fs->dnVecDescr_X, cusparse_scalartype, alg, fs->spsvDescr_Lt));

1516:   // Reorder X with the column permutation if needed, and put the result back to x
1517:   if (fs->cpermIndices) {
1518:     PetscCallThrust(thrust::copy(thrust::cuda::par.on(PetscDefaultCudaStream), thrust::make_permutation_iterator(thrust::device_pointer_cast(fs->X), fs->cpermIndices->begin()),
1519:                                  thrust::make_permutation_iterator(thrust::device_pointer_cast(fs->X + m), fs->cpermIndices->end()), xGPU));
1520:   }

1522:   PetscCall(VecCUDARestoreArrayRead(b, &barray));
1523:   PetscCall(VecCUDARestoreArrayWrite(x, &xarray));
1524:   PetscCall(PetscLogGpuTimeEnd());
1525:   PetscCall(PetscLogGpuFlops(2.0 * aij->nz - A->rmap->n));
1526:   PetscFunctionReturn(PETSC_SUCCESS);
1527: }
1528: #else
1529: /* Why do we need to analyze the transposed matrix again? Can't we just use op(A) = CUSPARSE_OPERATION_TRANSPOSE in MatSolve_SeqAIJCUSPARSE? */
1530: static PetscErrorCode MatSolveTranspose_SeqAIJCUSPARSE(Mat A, Vec bb, Vec xx)
1531: {
1532:   PetscInt                              n = xx->map->n;
1533:   const PetscScalar                    *barray;
1534:   PetscScalar                          *xarray;
1535:   thrust::device_ptr<const PetscScalar> bGPU;
1536:   thrust::device_ptr<PetscScalar>       xGPU;
1537:   Mat_SeqAIJCUSPARSETriFactors         *cusparseTriFactors = (Mat_SeqAIJCUSPARSETriFactors *)A->spptr;
1538:   Mat_SeqAIJCUSPARSETriFactorStruct    *loTriFactorT       = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->loTriFactorPtrTranspose;
1539:   Mat_SeqAIJCUSPARSETriFactorStruct    *upTriFactorT       = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->upTriFactorPtrTranspose;
1540:   THRUSTARRAY                          *tempGPU            = (THRUSTARRAY *)cusparseTriFactors->workVector;

1542:   PetscFunctionBegin;
1543:   /* Analyze the matrix and create the transpose ... on the fly */
1544:   if (!loTriFactorT && !upTriFactorT) {
1545:     PetscCall(MatSeqAIJCUSPARSEAnalyzeTransposeForSolve(A));
1546:     loTriFactorT = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->loTriFactorPtrTranspose;
1547:     upTriFactorT = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->upTriFactorPtrTranspose;
1548:   }

1550:   /* Get the GPU pointers */
1551:   PetscCall(VecCUDAGetArrayWrite(xx, &xarray));
1552:   PetscCall(VecCUDAGetArrayRead(bb, &barray));
1553:   xGPU = thrust::device_pointer_cast(xarray);
1554:   bGPU = thrust::device_pointer_cast(barray);

1556:   PetscCall(PetscLogGpuTimeBegin());
1557:   /* First, reorder with the row permutation */
1558:   thrust::copy(thrust::cuda::par.on(PetscDefaultCudaStream), thrust::make_permutation_iterator(bGPU, cusparseTriFactors->rpermIndices->begin()), thrust::make_permutation_iterator(bGPU + n, cusparseTriFactors->rpermIndices->end()), xGPU);

1560:   /* First, solve U */
1561:   PetscCallCUSPARSE(cusparseXcsrsv_solve(cusparseTriFactors->handle, upTriFactorT->solveOp, upTriFactorT->csrMat->num_rows, upTriFactorT->csrMat->num_entries, &PETSC_CUSPARSE_ONE, upTriFactorT->descr, upTriFactorT->csrMat->values->data().get(),
1562:                                          upTriFactorT->csrMat->row_offsets->data().get(), upTriFactorT->csrMat->column_indices->data().get(), upTriFactorT->solveInfo, xarray, tempGPU->data().get(), upTriFactorT->solvePolicy, upTriFactorT->solveBuffer));

1564:   /* Then, solve L */
1565:   PetscCallCUSPARSE(cusparseXcsrsv_solve(cusparseTriFactors->handle, loTriFactorT->solveOp, loTriFactorT->csrMat->num_rows, loTriFactorT->csrMat->num_entries, &PETSC_CUSPARSE_ONE, loTriFactorT->descr, loTriFactorT->csrMat->values->data().get(),
1566:                                          loTriFactorT->csrMat->row_offsets->data().get(), loTriFactorT->csrMat->column_indices->data().get(), loTriFactorT->solveInfo, tempGPU->data().get(), xarray, loTriFactorT->solvePolicy, loTriFactorT->solveBuffer));

1568:   /* Last, copy the solution, xGPU, into a temporary with the column permutation ... can't be done in place. */
1569:   thrust::copy(thrust::cuda::par.on(PetscDefaultCudaStream), thrust::make_permutation_iterator(xGPU, cusparseTriFactors->cpermIndices->begin()), thrust::make_permutation_iterator(xGPU + n, cusparseTriFactors->cpermIndices->end()), tempGPU->begin());

1571:   /* Copy the temporary to the full solution. */
1572:   thrust::copy(thrust::cuda::par.on(PetscDefaultCudaStream), tempGPU->begin(), tempGPU->end(), xGPU);

1574:   /* restore */
1575:   PetscCall(VecCUDARestoreArrayRead(bb, &barray));
1576:   PetscCall(VecCUDARestoreArrayWrite(xx, &xarray));
1577:   PetscCall(PetscLogGpuTimeEnd());
1578:   PetscCall(PetscLogGpuFlops(2.0 * cusparseTriFactors->nnz - A->cmap->n));
1579:   PetscFunctionReturn(PETSC_SUCCESS);
1580: }

1582: static PetscErrorCode MatSolveTranspose_SeqAIJCUSPARSE_NaturalOrdering(Mat A, Vec bb, Vec xx)
1583: {
1584:   const PetscScalar                 *barray;
1585:   PetscScalar                       *xarray;
1586:   Mat_SeqAIJCUSPARSETriFactors      *cusparseTriFactors = (Mat_SeqAIJCUSPARSETriFactors *)A->spptr;
1587:   Mat_SeqAIJCUSPARSETriFactorStruct *loTriFactorT       = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->loTriFactorPtrTranspose;
1588:   Mat_SeqAIJCUSPARSETriFactorStruct *upTriFactorT       = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->upTriFactorPtrTranspose;
1589:   THRUSTARRAY                       *tempGPU            = (THRUSTARRAY *)cusparseTriFactors->workVector;

1591:   PetscFunctionBegin;
1592:   /* Analyze the matrix and create the transpose ... on the fly */
1593:   if (!loTriFactorT && !upTriFactorT) {
1594:     PetscCall(MatSeqAIJCUSPARSEAnalyzeTransposeForSolve(A));
1595:     loTriFactorT = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->loTriFactorPtrTranspose;
1596:     upTriFactorT = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->upTriFactorPtrTranspose;
1597:   }

1599:   /* Get the GPU pointers */
1600:   PetscCall(VecCUDAGetArrayWrite(xx, &xarray));
1601:   PetscCall(VecCUDAGetArrayRead(bb, &barray));

1603:   PetscCall(PetscLogGpuTimeBegin());
1604:   /* First, solve U */
1605:   PetscCallCUSPARSE(cusparseXcsrsv_solve(cusparseTriFactors->handle, upTriFactorT->solveOp, upTriFactorT->csrMat->num_rows, upTriFactorT->csrMat->num_entries, &PETSC_CUSPARSE_ONE, upTriFactorT->descr, upTriFactorT->csrMat->values->data().get(),
1606:                                          upTriFactorT->csrMat->row_offsets->data().get(), upTriFactorT->csrMat->column_indices->data().get(), upTriFactorT->solveInfo, barray, tempGPU->data().get(), upTriFactorT->solvePolicy, upTriFactorT->solveBuffer));

1608:   /* Then, solve L */
1609:   PetscCallCUSPARSE(cusparseXcsrsv_solve(cusparseTriFactors->handle, loTriFactorT->solveOp, loTriFactorT->csrMat->num_rows, loTriFactorT->csrMat->num_entries, &PETSC_CUSPARSE_ONE, loTriFactorT->descr, loTriFactorT->csrMat->values->data().get(),
1610:                                          loTriFactorT->csrMat->row_offsets->data().get(), loTriFactorT->csrMat->column_indices->data().get(), loTriFactorT->solveInfo, tempGPU->data().get(), xarray, loTriFactorT->solvePolicy, loTriFactorT->solveBuffer));

1612:   /* restore */
1613:   PetscCall(VecCUDARestoreArrayRead(bb, &barray));
1614:   PetscCall(VecCUDARestoreArrayWrite(xx, &xarray));
1615:   PetscCall(PetscLogGpuTimeEnd());
1616:   PetscCall(PetscLogGpuFlops(2.0 * cusparseTriFactors->nnz - A->cmap->n));
1617:   PetscFunctionReturn(PETSC_SUCCESS);
1618: }

1620: static PetscErrorCode MatSolve_SeqAIJCUSPARSE(Mat A, Vec bb, Vec xx)
1621: {
1622:   const PetscScalar                    *barray;
1623:   PetscScalar                          *xarray;
1624:   thrust::device_ptr<const PetscScalar> bGPU;
1625:   thrust::device_ptr<PetscScalar>       xGPU;
1626:   Mat_SeqAIJCUSPARSETriFactors         *cusparseTriFactors = (Mat_SeqAIJCUSPARSETriFactors *)A->spptr;
1627:   Mat_SeqAIJCUSPARSETriFactorStruct    *loTriFactor        = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->loTriFactorPtr;
1628:   Mat_SeqAIJCUSPARSETriFactorStruct    *upTriFactor        = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->upTriFactorPtr;
1629:   THRUSTARRAY                          *tempGPU            = (THRUSTARRAY *)cusparseTriFactors->workVector;

1631:   PetscFunctionBegin;
1632:   /* Get the GPU pointers */
1633:   PetscCall(VecCUDAGetArrayWrite(xx, &xarray));
1634:   PetscCall(VecCUDAGetArrayRead(bb, &barray));
1635:   xGPU = thrust::device_pointer_cast(xarray);
1636:   bGPU = thrust::device_pointer_cast(barray);

1638:   PetscCall(PetscLogGpuTimeBegin());
1639:   /* First, reorder with the row permutation */
1640:   thrust::copy(thrust::cuda::par.on(PetscDefaultCudaStream), thrust::make_permutation_iterator(bGPU, cusparseTriFactors->rpermIndices->begin()), thrust::make_permutation_iterator(bGPU, cusparseTriFactors->rpermIndices->end()), tempGPU->begin());

1642:   /* Next, solve L */
1643:   PetscCallCUSPARSE(cusparseXcsrsv_solve(cusparseTriFactors->handle, loTriFactor->solveOp, loTriFactor->csrMat->num_rows, loTriFactor->csrMat->num_entries, &PETSC_CUSPARSE_ONE, loTriFactor->descr, loTriFactor->csrMat->values->data().get(),
1644:                                          loTriFactor->csrMat->row_offsets->data().get(), loTriFactor->csrMat->column_indices->data().get(), loTriFactor->solveInfo, tempGPU->data().get(), xarray, loTriFactor->solvePolicy, loTriFactor->solveBuffer));

1646:   /* Then, solve U */
1647:   PetscCallCUSPARSE(cusparseXcsrsv_solve(cusparseTriFactors->handle, upTriFactor->solveOp, upTriFactor->csrMat->num_rows, upTriFactor->csrMat->num_entries, &PETSC_CUSPARSE_ONE, upTriFactor->descr, upTriFactor->csrMat->values->data().get(),
1648:                                          upTriFactor->csrMat->row_offsets->data().get(), upTriFactor->csrMat->column_indices->data().get(), upTriFactor->solveInfo, xarray, tempGPU->data().get(), upTriFactor->solvePolicy, upTriFactor->solveBuffer));

1650:   /* Last, reorder with the column permutation */
1651:   thrust::copy(thrust::cuda::par.on(PetscDefaultCudaStream), thrust::make_permutation_iterator(tempGPU->begin(), cusparseTriFactors->cpermIndices->begin()), thrust::make_permutation_iterator(tempGPU->begin(), cusparseTriFactors->cpermIndices->end()), xGPU);

1653:   PetscCall(VecCUDARestoreArrayRead(bb, &barray));
1654:   PetscCall(VecCUDARestoreArrayWrite(xx, &xarray));
1655:   PetscCall(PetscLogGpuTimeEnd());
1656:   PetscCall(PetscLogGpuFlops(2.0 * cusparseTriFactors->nnz - A->cmap->n));
1657:   PetscFunctionReturn(PETSC_SUCCESS);
1658: }

1660: static PetscErrorCode MatSolve_SeqAIJCUSPARSE_NaturalOrdering(Mat A, Vec bb, Vec xx)
1661: {
1662:   const PetscScalar                 *barray;
1663:   PetscScalar                       *xarray;
1664:   Mat_SeqAIJCUSPARSETriFactors      *cusparseTriFactors = (Mat_SeqAIJCUSPARSETriFactors *)A->spptr;
1665:   Mat_SeqAIJCUSPARSETriFactorStruct *loTriFactor        = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->loTriFactorPtr;
1666:   Mat_SeqAIJCUSPARSETriFactorStruct *upTriFactor        = (Mat_SeqAIJCUSPARSETriFactorStruct *)cusparseTriFactors->upTriFactorPtr;
1667:   THRUSTARRAY                       *tempGPU            = (THRUSTARRAY *)cusparseTriFactors->workVector;

1669:   PetscFunctionBegin;
1670:   /* Get the GPU pointers */
1671:   PetscCall(VecCUDAGetArrayWrite(xx, &xarray));
1672:   PetscCall(VecCUDAGetArrayRead(bb, &barray));

1674:   PetscCall(PetscLogGpuTimeBegin());
1675:   /* First, solve L */
1676:   PetscCallCUSPARSE(cusparseXcsrsv_solve(cusparseTriFactors->handle, loTriFactor->solveOp, loTriFactor->csrMat->num_rows, loTriFactor->csrMat->num_entries, &PETSC_CUSPARSE_ONE, loTriFactor->descr, loTriFactor->csrMat->values->data().get(),
1677:                                          loTriFactor->csrMat->row_offsets->data().get(), loTriFactor->csrMat->column_indices->data().get(), loTriFactor->solveInfo, barray, tempGPU->data().get(), loTriFactor->solvePolicy, loTriFactor->solveBuffer));

1679:   /* Next, solve U */
1680:   PetscCallCUSPARSE(cusparseXcsrsv_solve(cusparseTriFactors->handle, upTriFactor->solveOp, upTriFactor->csrMat->num_rows, upTriFactor->csrMat->num_entries, &PETSC_CUSPARSE_ONE, upTriFactor->descr, upTriFactor->csrMat->values->data().get(),
1681:                                          upTriFactor->csrMat->row_offsets->data().get(), upTriFactor->csrMat->column_indices->data().get(), upTriFactor->solveInfo, tempGPU->data().get(), xarray, upTriFactor->solvePolicy, upTriFactor->solveBuffer));

1683:   PetscCall(VecCUDARestoreArrayRead(bb, &barray));
1684:   PetscCall(VecCUDARestoreArrayWrite(xx, &xarray));
1685:   PetscCall(PetscLogGpuTimeEnd());
1686:   PetscCall(PetscLogGpuFlops(2.0 * cusparseTriFactors->nnz - A->cmap->n));
1687:   PetscFunctionReturn(PETSC_SUCCESS);
1688: }
1689: #endif

1691: #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
1692: static PetscErrorCode MatILUFactorNumeric_SeqAIJCUSPARSE_ILU0(Mat fact, Mat A, const MatFactorInfo *)
1693: {
1694:   Mat_SeqAIJCUSPARSETriFactors *fs    = (Mat_SeqAIJCUSPARSETriFactors *)fact->spptr;
1695:   Mat_SeqAIJ                   *aij   = (Mat_SeqAIJ *)fact->data;
1696:   Mat_SeqAIJCUSPARSE           *Acusp = (Mat_SeqAIJCUSPARSE *)A->spptr;
1697:   CsrMatrix                    *Acsr;
1698:   PetscInt                      m, nz;
1699:   PetscBool                     flg;

1701:   PetscFunctionBegin;
1702:   if (PetscDefined(USE_DEBUG)) {
1703:     PetscCall(PetscObjectTypeCompare((PetscObject)A, MATSEQAIJCUSPARSE, &flg));
1704:     PetscCheck(flg, PetscObjectComm((PetscObject)A), PETSC_ERR_GPU, "Expected MATSEQAIJCUSPARSE, but input is %s", ((PetscObject)A)->type_name);
1705:   }

1707:   /* Copy A's value to fact */
1708:   m  = fact->rmap->n;
1709:   nz = aij->nz;
1710:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));
1711:   Acsr = (CsrMatrix *)Acusp->mat->mat;
1712:   PetscCallCUDA(cudaMemcpyAsync(fs->csrVal, Acsr->values->data().get(), sizeof(PetscScalar) * nz, cudaMemcpyDeviceToDevice, PetscDefaultCudaStream));

1714:   PetscCall(PetscLogGpuTimeBegin());
1715:   /* Factorize fact inplace */
1716:   if (m)
1717:     PetscCallCUSPARSE(cusparseXcsrilu02(fs->handle, m, nz, /* cusparseXcsrilu02 errors out with empty matrices (m=0) */
1718:                                         fs->matDescr_M, fs->csrVal, fs->csrRowPtr32, fs->csrColIdx32, fs->ilu0Info_M, fs->policy_M, fs->factBuffer_M));
1719:   if (PetscDefined(USE_DEBUG)) {
1720:     int              numerical_zero;
1721:     cusparseStatus_t status;
1722:     status = cusparseXcsrilu02_zeroPivot(fs->handle, fs->ilu0Info_M, &numerical_zero);
1723:     PetscAssert(CUSPARSE_STATUS_ZERO_PIVOT != status, PETSC_COMM_SELF, PETSC_ERR_USER_INPUT, "Numerical zero pivot detected in csrilu02: A(%d,%d) is zero", numerical_zero, numerical_zero);
1724:   }

1726:   #if PETSC_PKG_CUDA_VERSION_GE(12, 1, 1)
1727:   if (fs->updatedSpSVAnalysis) {
1728:     if (fs->csrVal) PetscCallCUSPARSE(cusparseSpSV_updateMatrix(fs->handle, fs->spsvDescr_L, fs->csrVal, CUSPARSE_SPSV_UPDATE_GENERAL));
1729:     if (fs->csrVal) PetscCallCUSPARSE(cusparseSpSV_updateMatrix(fs->handle, fs->spsvDescr_U, fs->csrVal, CUSPARSE_SPSV_UPDATE_GENERAL));
1730:   } else
1731:   #endif
1732:   {
1733:     /* cusparseSpSV_analysis() is numeric, i.e., it requires valid matrix values, therefore, we do it after cusparseXcsrilu02()
1734:      See discussion at https://github.com/NVIDIA/CUDALibrarySamples/issues/78
1735:     */
1736:     PetscCallCUSPARSE(cusparseSpSV_analysis(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_L, fs->spsvBuffer_L));

1738:     PetscCallCUSPARSE(cusparseSpSV_analysis(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_U, fs->spsvBuffer_U));

1740:     fs->updatedSpSVAnalysis = PETSC_TRUE;
1741:     /* L, U values have changed, reset the flag to indicate we need to redo cusparseSpSV_analysis() for transpose solve */
1742:     fs->updatedTransposeSpSVAnalysis = PETSC_FALSE;
1743:   }

1745:   fact->offloadmask            = PETSC_OFFLOAD_GPU;
1746:   fact->ops->solve             = MatSolve_SeqAIJCUSPARSE_LU; // spMatDescr_L/U uses 32-bit indices, but cusparseSpSV_solve() supports both 32 and 64. The info is encoded in cusparseSpMatDescr_t.
1747:   fact->ops->solvetranspose    = MatSolveTranspose_SeqAIJCUSPARSE_LU;
1748:   fact->ops->matsolve          = NULL;
1749:   fact->ops->matsolvetranspose = NULL;
1750:   PetscCall(PetscLogGpuTimeEnd());
1751:   PetscCall(PetscLogGpuFlops(fs->numericFactFlops));
1752:   PetscFunctionReturn(PETSC_SUCCESS);
1753: }

1755: static PetscErrorCode MatILUFactorSymbolic_SeqAIJCUSPARSE_ILU0(Mat fact, Mat A, IS, IS, const MatFactorInfo *info)
1756: {
1757:   Mat_SeqAIJCUSPARSETriFactors *fs  = (Mat_SeqAIJCUSPARSETriFactors *)fact->spptr;
1758:   Mat_SeqAIJ                   *aij = (Mat_SeqAIJ *)fact->data;
1759:   PetscInt                      m, nz;

1761:   PetscFunctionBegin;
1762:   if (PetscDefined(USE_DEBUG)) {
1763:     PetscBool flg, diagDense;

1765:     PetscCall(PetscObjectTypeCompare((PetscObject)A, MATSEQAIJCUSPARSE, &flg));
1766:     PetscCheck(flg, PetscObjectComm((PetscObject)A), PETSC_ERR_GPU, "Expected MATSEQAIJCUSPARSE, but input is %s", ((PetscObject)A)->type_name);
1767:     PetscCheck(A->rmap->n == A->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Must be square matrix, rows %" PetscInt_FMT " columns %" PetscInt_FMT, A->rmap->n, A->cmap->n);
1768:     PetscCall(MatGetDiagonalMarkers_SeqAIJ(A, NULL, &diagDense));
1769:     PetscCheck(diagDense, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Matrix is missing a diagonal entry");
1770:   }

1772:   /* Free the old stale stuff */
1773:   PetscCall(MatSeqAIJCUSPARSETriFactors_Reset(&fs));

1775:   /* Copy over A's meta data to fact. Note that we also allocated fact's i,j,a on host,
1776:      but they will not be used. Allocate them just for easy debugging.
1777:    */
1778:   PetscCall(MatDuplicateNoCreate_SeqAIJ(fact, A, MAT_DO_NOT_COPY_VALUES, PETSC_TRUE /*malloc*/));

1780:   fact->offloadmask            = PETSC_OFFLOAD_BOTH;
1781:   fact->factortype             = MAT_FACTOR_ILU;
1782:   fact->info.factor_mallocs    = 0;
1783:   fact->info.fill_ratio_given  = info->fill;
1784:   fact->info.fill_ratio_needed = 1.0;

1786:   aij->row = NULL;
1787:   aij->col = NULL;

1789:   /* ====================================================================== */
1790:   /* Copy A's i, j to fact and also allocate the value array of fact.       */
1791:   /* We'll do in-place factorization on fact                                */
1792:   /* ====================================================================== */
1793:   const int *Ai, *Aj;

1795:   m  = fact->rmap->n;
1796:   nz = aij->nz;

1798:   PetscCallCUDA(cudaMalloc((void **)&fs->csrRowPtr32, sizeof(*fs->csrRowPtr32) * (m + 1)));
1799:   PetscCallCUDA(cudaMalloc((void **)&fs->csrColIdx32, sizeof(*fs->csrColIdx32) * nz));
1800:   PetscCallCUDA(cudaMalloc((void **)&fs->csrVal, sizeof(*fs->csrVal) * nz));
1801:   PetscCall(MatSeqAIJCUSPARSEGetIJ(A, PETSC_FALSE, &Ai, &Aj)); /* Do not use compressed Ai.  The returned Ai, Aj are 32-bit */
1802:   PetscCallCUDA(cudaMemcpyAsync(fs->csrRowPtr32, Ai, sizeof(*Ai) * (m + 1), cudaMemcpyDeviceToDevice, PetscDefaultCudaStream));
1803:   PetscCallCUDA(cudaMemcpyAsync(fs->csrColIdx32, Aj, sizeof(*Aj) * nz, cudaMemcpyDeviceToDevice, PetscDefaultCudaStream));

1805:   /* ====================================================================== */
1806:   /* Create descriptors for M, L, U                                         */
1807:   /* ====================================================================== */
1808:   cusparseFillMode_t fillMode;
1809:   cusparseDiagType_t diagType;

1811:   PetscCallCUSPARSE(cusparseCreateMatDescr(&fs->matDescr_M));
1812:   PetscCallCUSPARSE(cusparseSetMatIndexBase(fs->matDescr_M, CUSPARSE_INDEX_BASE_ZERO));
1813:   PetscCallCUSPARSE(cusparseSetMatType(fs->matDescr_M, CUSPARSE_MATRIX_TYPE_GENERAL));

1815:   /* https://docs.nvidia.com/cuda/cusparse/index.html#cusparseDiagType_t
1816:     cusparseDiagType_t: This type indicates if the matrix diagonal entries are unity. The diagonal elements are always
1817:     assumed to be present, but if CUSPARSE_DIAG_TYPE_UNIT is passed to an API routine, then the routine assumes that
1818:     all diagonal entries are unity and will not read or modify those entries. Note that in this case the routine
1819:     assumes the diagonal entries are equal to one, regardless of what those entries are actually set to in memory.
1820:   */
1821:   fillMode = CUSPARSE_FILL_MODE_LOWER;
1822:   diagType = CUSPARSE_DIAG_TYPE_UNIT;
1823:   PetscCallCUSPARSE(cusparseCreateCsr(&fs->spMatDescr_L, m, m, nz, fs->csrRowPtr32, fs->csrColIdx32, fs->csrVal, CUSPARSE_INDEX_32I, CUSPARSE_INDEX_32I, CUSPARSE_INDEX_BASE_ZERO, cusparse_scalartype));
1824:   PetscCallCUSPARSE(cusparseSpMatSetAttribute(fs->spMatDescr_L, CUSPARSE_SPMAT_FILL_MODE, &fillMode, sizeof(fillMode)));
1825:   PetscCallCUSPARSE(cusparseSpMatSetAttribute(fs->spMatDescr_L, CUSPARSE_SPMAT_DIAG_TYPE, &diagType, sizeof(diagType)));

1827:   fillMode = CUSPARSE_FILL_MODE_UPPER;
1828:   diagType = CUSPARSE_DIAG_TYPE_NON_UNIT;
1829:   PetscCallCUSPARSE(cusparseCreateCsr(&fs->spMatDescr_U, m, m, nz, fs->csrRowPtr32, fs->csrColIdx32, fs->csrVal, CUSPARSE_INDEX_32I, CUSPARSE_INDEX_32I, CUSPARSE_INDEX_BASE_ZERO, cusparse_scalartype));
1830:   PetscCallCUSPARSE(cusparseSpMatSetAttribute(fs->spMatDescr_U, CUSPARSE_SPMAT_FILL_MODE, &fillMode, sizeof(fillMode)));
1831:   PetscCallCUSPARSE(cusparseSpMatSetAttribute(fs->spMatDescr_U, CUSPARSE_SPMAT_DIAG_TYPE, &diagType, sizeof(diagType)));

1833:   /* ========================================================================= */
1834:   /* Query buffer sizes for csrilu0, SpSV and allocate buffers                 */
1835:   /* ========================================================================= */
1836:   PetscCallCUSPARSE(cusparseCreateCsrilu02Info(&fs->ilu0Info_M));
1837:   if (m)
1838:     PetscCallCUSPARSE(cusparseXcsrilu02_bufferSize(fs->handle, m, nz, /* cusparseXcsrilu02 errors out with empty matrices (m=0) */
1839:                                                    fs->matDescr_M, fs->csrVal, fs->csrRowPtr32, fs->csrColIdx32, fs->ilu0Info_M, &fs->factBufferSize_M));

1841:   PetscCallCUDA(cudaMalloc((void **)&fs->X, sizeof(PetscScalar) * m));
1842:   PetscCallCUDA(cudaMalloc((void **)&fs->Y, sizeof(PetscScalar) * m));

1844:   PetscCallCUSPARSE(cusparseCreateDnVec(&fs->dnVecDescr_X, m, fs->X, cusparse_scalartype));
1845:   PetscCallCUSPARSE(cusparseCreateDnVec(&fs->dnVecDescr_Y, m, fs->Y, cusparse_scalartype));

1847:   PetscCallCUSPARSE(cusparseSpSV_createDescr(&fs->spsvDescr_L));
1848:   PetscCallCUSPARSE(cusparseSpSV_bufferSize(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_L, &fs->spsvBufferSize_L));

1850:   PetscCallCUSPARSE(cusparseSpSV_createDescr(&fs->spsvDescr_U));
1851:   PetscCallCUSPARSE(cusparseSpSV_bufferSize(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_U, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_U, &fs->spsvBufferSize_U));

1853:   /* From my experiment with the example at https://github.com/NVIDIA/CUDALibrarySamples/tree/master/cuSPARSE/bicgstab,
1854:      and discussion at https://github.com/NVIDIA/CUDALibrarySamples/issues/77,
1855:      spsvBuffer_L/U can not be shared (i.e., the same) for our case, but factBuffer_M can share with either of spsvBuffer_L/U.
1856:      To save memory, we make factBuffer_M share with the bigger of spsvBuffer_L/U.
1857:    */
1858:   if (fs->spsvBufferSize_L > fs->spsvBufferSize_U) {
1859:     PetscCallCUDA(cudaMalloc((void **)&fs->factBuffer_M, PetscMax(fs->spsvBufferSize_L, (size_t)fs->factBufferSize_M)));
1860:     fs->spsvBuffer_L = fs->factBuffer_M;
1861:     PetscCallCUDA(cudaMalloc((void **)&fs->spsvBuffer_U, fs->spsvBufferSize_U));
1862:   } else {
1863:     PetscCallCUDA(cudaMalloc((void **)&fs->factBuffer_M, PetscMax(fs->spsvBufferSize_U, (size_t)fs->factBufferSize_M)));
1864:     fs->spsvBuffer_U = fs->factBuffer_M;
1865:     PetscCallCUDA(cudaMalloc((void **)&fs->spsvBuffer_L, fs->spsvBufferSize_L));
1866:   }

1868:   /* ========================================================================== */
1869:   /* Perform analysis of ilu0 on M, SpSv on L and U                             */
1870:   /* The lower(upper) triangular part of M has the same sparsity pattern as L(U)*/
1871:   /* ========================================================================== */
1872:   int              structural_zero;
1873:   cusparseStatus_t status;

1875:   fs->policy_M = CUSPARSE_SOLVE_POLICY_USE_LEVEL;
1876:   if (m)
1877:     PetscCallCUSPARSE(cusparseXcsrilu02_analysis(fs->handle, m, nz, /* cusparseXcsrilu02 errors out with empty matrices (m=0) */
1878:                                                  fs->matDescr_M, fs->csrVal, fs->csrRowPtr32, fs->csrColIdx32, fs->ilu0Info_M, fs->policy_M, fs->factBuffer_M));
1879:   if (PetscDefined(USE_DEBUG)) {
1880:     /* cusparseXcsrilu02_zeroPivot() is a blocking call. It calls cudaDeviceSynchronize() to make sure all previous kernels are done. */
1881:     status = cusparseXcsrilu02_zeroPivot(fs->handle, fs->ilu0Info_M, &structural_zero);
1882:     PetscCheck(CUSPARSE_STATUS_ZERO_PIVOT != status, PETSC_COMM_SELF, PETSC_ERR_USER_INPUT, "Structural zero pivot detected in csrilu02: A(%d,%d) is missing", structural_zero, structural_zero);
1883:   }

1885:   /* Estimate FLOPs of the numeric factorization */
1886:   {
1887:     Mat_SeqAIJ     *Aseq = (Mat_SeqAIJ *)A->data;
1888:     PetscInt       *Ai, nzRow, nzLeft;
1889:     const PetscInt *adiag;
1890:     PetscLogDouble  flops = 0.0;

1892:     PetscCall(MatGetDiagonalMarkers_SeqAIJ(A, &adiag, NULL));
1893:     Ai = Aseq->i;
1894:     for (PetscInt i = 0; i < m; i++) {
1895:       if (Ai[i] < adiag[i] && adiag[i] < Ai[i + 1]) { /* There are nonzeros left to the diagonal of row i */
1896:         nzRow  = Ai[i + 1] - Ai[i];
1897:         nzLeft = adiag[i] - Ai[i];
1898:         /* We want to eliminate nonzeros left to the diagonal one by one. Assume each time, nonzeros right
1899:           and include the eliminated one will be updated, which incurs a multiplication and an addition.
1900:         */
1901:         nzLeft = (nzRow - 1) / 2;
1902:         flops += nzLeft * (2.0 * nzRow - nzLeft + 1);
1903:       }
1904:     }
1905:     fs->numericFactFlops = flops;
1906:   }
1907:   fact->ops->lufactornumeric = MatILUFactorNumeric_SeqAIJCUSPARSE_ILU0;
1908:   PetscFunctionReturn(PETSC_SUCCESS);
1909: }

1911: static PetscErrorCode MatSolve_SeqAIJCUSPARSE_ICC0(Mat fact, Vec b, Vec x)
1912: {
1913:   Mat_SeqAIJCUSPARSETriFactors *fs  = (Mat_SeqAIJCUSPARSETriFactors *)fact->spptr;
1914:   Mat_SeqAIJ                   *aij = (Mat_SeqAIJ *)fact->data;
1915:   const PetscScalar            *barray;
1916:   PetscScalar                  *xarray;

1918:   PetscFunctionBegin;
1919:   PetscCall(VecCUDAGetArrayWrite(x, &xarray));
1920:   PetscCall(VecCUDAGetArrayRead(b, &barray));
1921:   PetscCall(PetscLogGpuTimeBegin());

1923:   /* Solve L*y = b */
1924:   PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, (void *)barray));
1925:   PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_Y, fs->Y));
1926:   PetscCallCUSPARSE(cusparseSpSV_solve(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, /* L Y = X */
1927:                                        fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_L));

1929:   /* Solve Lt*x = y */
1930:   PetscCallCUSPARSE(cusparseDnVecSetValues(fs->dnVecDescr_X, xarray));
1931:   PetscCallCUSPARSE(cusparseSpSV_solve(fs->handle, CUSPARSE_OPERATION_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, /* Lt X = Y */
1932:                                        fs->dnVecDescr_Y, fs->dnVecDescr_X, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_Lt));

1934:   PetscCall(VecCUDARestoreArrayRead(b, &barray));
1935:   PetscCall(VecCUDARestoreArrayWrite(x, &xarray));

1937:   PetscCall(PetscLogGpuTimeEnd());
1938:   PetscCall(PetscLogGpuFlops(2.0 * aij->nz - fact->rmap->n));
1939:   PetscFunctionReturn(PETSC_SUCCESS);
1940: }

1942: static PetscErrorCode MatICCFactorNumeric_SeqAIJCUSPARSE_ICC0(Mat fact, Mat A, const MatFactorInfo *)
1943: {
1944:   Mat_SeqAIJCUSPARSETriFactors *fs    = (Mat_SeqAIJCUSPARSETriFactors *)fact->spptr;
1945:   Mat_SeqAIJ                   *aij   = (Mat_SeqAIJ *)fact->data;
1946:   Mat_SeqAIJCUSPARSE           *Acusp = (Mat_SeqAIJCUSPARSE *)A->spptr;
1947:   CsrMatrix                    *Acsr;
1948:   PetscInt                      m, nz;
1949:   PetscBool                     flg;

1951:   PetscFunctionBegin;
1952:   if (PetscDefined(USE_DEBUG)) {
1953:     PetscCall(PetscObjectTypeCompare((PetscObject)A, MATSEQAIJCUSPARSE, &flg));
1954:     PetscCheck(flg, PetscObjectComm((PetscObject)A), PETSC_ERR_GPU, "Expected MATSEQAIJCUSPARSE, but input is %s", ((PetscObject)A)->type_name);
1955:   }

1957:   /* Copy A's value to fact */
1958:   m  = fact->rmap->n;
1959:   nz = aij->nz;
1960:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));
1961:   Acsr = (CsrMatrix *)Acusp->mat->mat;
1962:   PetscCallCUDA(cudaMemcpyAsync(fs->csrVal, Acsr->values->data().get(), sizeof(PetscScalar) * nz, cudaMemcpyDeviceToDevice, PetscDefaultCudaStream));

1964:   /* Factorize fact inplace */
1965:   /* https://docs.nvidia.com/cuda/cusparse/index.html#csric02_solve
1966:      csric02() only takes the lower triangular part of matrix A to perform factorization.
1967:      The matrix type must be CUSPARSE_MATRIX_TYPE_GENERAL, the fill mode and diagonal type are ignored,
1968:      and the strictly upper triangular part is ignored and never touched. It does not matter if A is Hermitian or not.
1969:      In other words, from the point of view of csric02() A is Hermitian and only the lower triangular part is provided.
1970:    */
1971:   if (m) PetscCallCUSPARSE(cusparseXcsric02(fs->handle, m, nz, fs->matDescr_M, fs->csrVal, fs->csrRowPtr32, fs->csrColIdx32, fs->ic0Info_M, fs->policy_M, fs->factBuffer_M));
1972:   if (PetscDefined(USE_DEBUG)) {
1973:     int              numerical_zero;
1974:     cusparseStatus_t status;
1975:     status = cusparseXcsric02_zeroPivot(fs->handle, fs->ic0Info_M, &numerical_zero);
1976:     PetscAssert(CUSPARSE_STATUS_ZERO_PIVOT != status, PETSC_COMM_SELF, PETSC_ERR_USER_INPUT, "Numerical zero pivot detected in csric02: A(%d,%d) is zero", numerical_zero, numerical_zero);
1977:   }

1979:   #if PETSC_PKG_CUDA_VERSION_GE(12, 1, 1)
1980:   if (fs->updatedSpSVAnalysis) {
1981:     if (fs->csrVal) PetscCallCUSPARSE(cusparseSpSV_updateMatrix(fs->handle, fs->spsvDescr_L, fs->csrVal, CUSPARSE_SPSV_UPDATE_GENERAL));
1982:     if (fs->csrVal) PetscCallCUSPARSE(cusparseSpSV_updateMatrix(fs->handle, fs->spsvDescr_Lt, fs->csrVal, CUSPARSE_SPSV_UPDATE_GENERAL));
1983:   } else
1984:   #endif
1985:   {
1986:     PetscCallCUSPARSE(cusparseSpSV_analysis(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_L, fs->spsvBuffer_L));

1988:     /* Note that cusparse reports this error if we use double and CUSPARSE_OPERATION_CONJUGATE_TRANSPOSE
1989:     ** On entry to cusparseSpSV_analysis(): conjugate transpose (opA) is not supported for matA data type, current -> CUDA_R_64F
1990:   */
1991:     PetscCallCUSPARSE(cusparseSpSV_analysis(fs->handle, CUSPARSE_OPERATION_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_Lt, fs->spsvBuffer_Lt));
1992:     fs->updatedSpSVAnalysis = PETSC_TRUE;
1993:   }

1995:   fact->offloadmask            = PETSC_OFFLOAD_GPU;
1996:   fact->ops->solve             = MatSolve_SeqAIJCUSPARSE_ICC0;
1997:   fact->ops->solvetranspose    = MatSolve_SeqAIJCUSPARSE_ICC0;
1998:   fact->ops->matsolve          = NULL;
1999:   fact->ops->matsolvetranspose = NULL;
2000:   PetscCall(PetscLogGpuFlops(fs->numericFactFlops));
2001:   PetscFunctionReturn(PETSC_SUCCESS);
2002: }

2004: static PetscErrorCode MatICCFactorSymbolic_SeqAIJCUSPARSE_ICC0(Mat fact, Mat A, IS, const MatFactorInfo *info)
2005: {
2006:   Mat_SeqAIJCUSPARSETriFactors *fs  = (Mat_SeqAIJCUSPARSETriFactors *)fact->spptr;
2007:   Mat_SeqAIJ                   *aij = (Mat_SeqAIJ *)fact->data;
2008:   PetscInt                      m, nz;

2010:   PetscFunctionBegin;
2011:   if (PetscDefined(USE_DEBUG)) {
2012:     PetscBool flg, diagDense;

2014:     PetscCall(PetscObjectTypeCompare((PetscObject)A, MATSEQAIJCUSPARSE, &flg));
2015:     PetscCheck(flg, PetscObjectComm((PetscObject)A), PETSC_ERR_GPU, "Expected MATSEQAIJCUSPARSE, but input is %s", ((PetscObject)A)->type_name);
2016:     PetscCheck(A->rmap->n == A->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Must be square matrix, rows %" PetscInt_FMT " columns %" PetscInt_FMT, A->rmap->n, A->cmap->n);
2017:     PetscCall(MatGetDiagonalMarkers_SeqAIJ(A, NULL, &diagDense));
2018:     PetscCheck(diagDense, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Matrix is missing diagonal entries");
2019:   }

2021:   /* Free the old stale stuff */
2022:   PetscCall(MatSeqAIJCUSPARSETriFactors_Reset(&fs));

2024:   /* Copy over A's meta data to fact. Note that we also allocated fact's i,j,a on host,
2025:      but they will not be used. Allocate them just for easy debugging.
2026:    */
2027:   PetscCall(MatDuplicateNoCreate_SeqAIJ(fact, A, MAT_DO_NOT_COPY_VALUES, PETSC_TRUE /*malloc*/));

2029:   fact->offloadmask            = PETSC_OFFLOAD_BOTH;
2030:   fact->factortype             = MAT_FACTOR_ICC;
2031:   fact->info.factor_mallocs    = 0;
2032:   fact->info.fill_ratio_given  = info->fill;
2033:   fact->info.fill_ratio_needed = 1.0;

2035:   aij->row = NULL;
2036:   aij->col = NULL;

2038:   /* ====================================================================== */
2039:   /* Copy A's i, j to fact and also allocate the value array of fact.       */
2040:   /* We'll do in-place factorization on fact                                */
2041:   /* ====================================================================== */
2042:   const int *Ai, *Aj;

2044:   m  = fact->rmap->n;
2045:   nz = aij->nz;

2047:   PetscCallCUDA(cudaMalloc((void **)&fs->csrRowPtr32, sizeof(*fs->csrRowPtr32) * (m + 1)));
2048:   PetscCallCUDA(cudaMalloc((void **)&fs->csrColIdx32, sizeof(*fs->csrColIdx32) * nz));
2049:   PetscCallCUDA(cudaMalloc((void **)&fs->csrVal, sizeof(PetscScalar) * nz));
2050:   PetscCall(MatSeqAIJCUSPARSEGetIJ(A, PETSC_FALSE, &Ai, &Aj)); /* Do not use compressed Ai */
2051:   PetscCallCUDA(cudaMemcpyAsync(fs->csrRowPtr32, Ai, sizeof(*Ai) * (m + 1), cudaMemcpyDeviceToDevice, PetscDefaultCudaStream));
2052:   PetscCallCUDA(cudaMemcpyAsync(fs->csrColIdx32, Aj, sizeof(*Aj) * nz, cudaMemcpyDeviceToDevice, PetscDefaultCudaStream));

2054:   /* ====================================================================== */
2055:   /* Create mat descriptors for M, L                                        */
2056:   /* ====================================================================== */
2057:   cusparseFillMode_t fillMode;
2058:   cusparseDiagType_t diagType;

2060:   PetscCallCUSPARSE(cusparseCreateMatDescr(&fs->matDescr_M));
2061:   PetscCallCUSPARSE(cusparseSetMatIndexBase(fs->matDescr_M, CUSPARSE_INDEX_BASE_ZERO));
2062:   PetscCallCUSPARSE(cusparseSetMatType(fs->matDescr_M, CUSPARSE_MATRIX_TYPE_GENERAL));

2064:   /* https://docs.nvidia.com/cuda/cusparse/index.html#cusparseDiagType_t
2065:     cusparseDiagType_t: This type indicates if the matrix diagonal entries are unity. The diagonal elements are always
2066:     assumed to be present, but if CUSPARSE_DIAG_TYPE_UNIT is passed to an API routine, then the routine assumes that
2067:     all diagonal entries are unity and will not read or modify those entries. Note that in this case the routine
2068:     assumes the diagonal entries are equal to one, regardless of what those entries are actually set to in memory.
2069:   */
2070:   fillMode = CUSPARSE_FILL_MODE_LOWER;
2071:   diagType = CUSPARSE_DIAG_TYPE_NON_UNIT;
2072:   PetscCallCUSPARSE(cusparseCreateCsr(&fs->spMatDescr_L, m, m, nz, fs->csrRowPtr32, fs->csrColIdx32, fs->csrVal, CUSPARSE_INDEX_32I, CUSPARSE_INDEX_32I, CUSPARSE_INDEX_BASE_ZERO, cusparse_scalartype));
2073:   PetscCallCUSPARSE(cusparseSpMatSetAttribute(fs->spMatDescr_L, CUSPARSE_SPMAT_FILL_MODE, &fillMode, sizeof(fillMode)));
2074:   PetscCallCUSPARSE(cusparseSpMatSetAttribute(fs->spMatDescr_L, CUSPARSE_SPMAT_DIAG_TYPE, &diagType, sizeof(diagType)));

2076:   /* ========================================================================= */
2077:   /* Query buffer sizes for csric0, SpSV of L and Lt, and allocate buffers     */
2078:   /* ========================================================================= */
2079:   PetscCallCUSPARSE(cusparseCreateCsric02Info(&fs->ic0Info_M));
2080:   if (m) PetscCallCUSPARSE(cusparseXcsric02_bufferSize(fs->handle, m, nz, fs->matDescr_M, fs->csrVal, fs->csrRowPtr32, fs->csrColIdx32, fs->ic0Info_M, &fs->factBufferSize_M));

2082:   PetscCallCUDA(cudaMalloc((void **)&fs->X, sizeof(PetscScalar) * m));
2083:   PetscCallCUDA(cudaMalloc((void **)&fs->Y, sizeof(PetscScalar) * m));

2085:   PetscCallCUSPARSE(cusparseCreateDnVec(&fs->dnVecDescr_X, m, fs->X, cusparse_scalartype));
2086:   PetscCallCUSPARSE(cusparseCreateDnVec(&fs->dnVecDescr_Y, m, fs->Y, cusparse_scalartype));

2088:   PetscCallCUSPARSE(cusparseSpSV_createDescr(&fs->spsvDescr_L));
2089:   PetscCallCUSPARSE(cusparseSpSV_bufferSize(fs->handle, CUSPARSE_OPERATION_NON_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_L, &fs->spsvBufferSize_L));

2091:   PetscCallCUSPARSE(cusparseSpSV_createDescr(&fs->spsvDescr_Lt));
2092:   PetscCallCUSPARSE(cusparseSpSV_bufferSize(fs->handle, CUSPARSE_OPERATION_TRANSPOSE, &PETSC_CUSPARSE_ONE, fs->spMatDescr_L, fs->dnVecDescr_X, fs->dnVecDescr_Y, cusparse_scalartype, CUSPARSE_SPSV_ALG_DEFAULT, fs->spsvDescr_Lt, &fs->spsvBufferSize_Lt));

2094:   /* To save device memory, we make the factorization buffer share with one of the solver buffer.
2095:      See also comments in MatILUFactorSymbolic_SeqAIJCUSPARSE_ILU0().
2096:    */
2097:   if (fs->spsvBufferSize_L > fs->spsvBufferSize_Lt) {
2098:     PetscCallCUDA(cudaMalloc((void **)&fs->factBuffer_M, PetscMax(fs->spsvBufferSize_L, (size_t)fs->factBufferSize_M)));
2099:     fs->spsvBuffer_L = fs->factBuffer_M;
2100:     PetscCallCUDA(cudaMalloc((void **)&fs->spsvBuffer_Lt, fs->spsvBufferSize_Lt));
2101:   } else {
2102:     PetscCallCUDA(cudaMalloc((void **)&fs->factBuffer_M, PetscMax(fs->spsvBufferSize_Lt, (size_t)fs->factBufferSize_M)));
2103:     fs->spsvBuffer_Lt = fs->factBuffer_M;
2104:     PetscCallCUDA(cudaMalloc((void **)&fs->spsvBuffer_L, fs->spsvBufferSize_L));
2105:   }

2107:   /* ========================================================================== */
2108:   /* Perform analysis of ic0 on M                                               */
2109:   /* The lower triangular part of M has the same sparsity pattern as L          */
2110:   /* ========================================================================== */
2111:   int              structural_zero;
2112:   cusparseStatus_t status;

2114:   fs->policy_M = CUSPARSE_SOLVE_POLICY_USE_LEVEL;
2115:   if (m) PetscCallCUSPARSE(cusparseXcsric02_analysis(fs->handle, m, nz, fs->matDescr_M, fs->csrVal, fs->csrRowPtr32, fs->csrColIdx32, fs->ic0Info_M, fs->policy_M, fs->factBuffer_M));
2116:   if (PetscDefined(USE_DEBUG)) {
2117:     /* cusparseXcsric02_zeroPivot() is a blocking call. It calls cudaDeviceSynchronize() to make sure all previous kernels are done. */
2118:     status = cusparseXcsric02_zeroPivot(fs->handle, fs->ic0Info_M, &structural_zero);
2119:     PetscCheck(CUSPARSE_STATUS_ZERO_PIVOT != status, PETSC_COMM_SELF, PETSC_ERR_USER_INPUT, "Structural zero pivot detected in csric02: A(%d,%d) is missing", structural_zero, structural_zero);
2120:   }

2122:   /* Estimate FLOPs of the numeric factorization */
2123:   {
2124:     Mat_SeqAIJ    *Aseq = (Mat_SeqAIJ *)A->data;
2125:     PetscInt      *Ai, nzRow, nzLeft;
2126:     PetscLogDouble flops = 0.0;

2128:     Ai = Aseq->i;
2129:     for (PetscInt i = 0; i < m; i++) {
2130:       nzRow = Ai[i + 1] - Ai[i];
2131:       if (nzRow > 1) {
2132:         /* We want to eliminate nonzeros left to the diagonal one by one. Assume each time, nonzeros right
2133:           and include the eliminated one will be updated, which incurs a multiplication and an addition.
2134:         */
2135:         nzLeft = (nzRow - 1) / 2;
2136:         flops += nzLeft * (2.0 * nzRow - nzLeft + 1);
2137:       }
2138:     }
2139:     fs->numericFactFlops = flops;
2140:   }
2141:   fact->ops->choleskyfactornumeric = MatICCFactorNumeric_SeqAIJCUSPARSE_ICC0;
2142:   PetscFunctionReturn(PETSC_SUCCESS);
2143: }
2144: #endif

2146: static PetscErrorCode MatLUFactorNumeric_SeqAIJCUSPARSE(Mat B, Mat A, const MatFactorInfo *info)
2147: {
2148:   // use_cpu_solve is a field in Mat_SeqAIJCUSPARSE. B, a factored matrix, uses Mat_SeqAIJCUSPARSETriFactors.
2149:   Mat_SeqAIJCUSPARSE *cusparsestruct = static_cast<Mat_SeqAIJCUSPARSE *>(A->spptr);

2151:   PetscFunctionBegin;
2152:   PetscCall(MatSeqAIJCUSPARSECopyFromGPU(A));
2153:   PetscCall(MatLUFactorNumeric_SeqAIJ(B, A, info));
2154:   B->offloadmask = PETSC_OFFLOAD_CPU;

2156:   if (!cusparsestruct->use_cpu_solve) {
2157: #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
2158:     B->ops->solve          = MatSolve_SeqAIJCUSPARSE_LU;
2159:     B->ops->solvetranspose = MatSolveTranspose_SeqAIJCUSPARSE_LU;
2160: #else
2161:     /* determine which version of MatSolve needs to be used. */
2162:     Mat_SeqAIJ *b     = (Mat_SeqAIJ *)B->data;
2163:     IS          isrow = b->row, iscol = b->col;
2164:     PetscBool   row_identity, col_identity;

2166:     PetscCall(ISIdentity(isrow, &row_identity));
2167:     PetscCall(ISIdentity(iscol, &col_identity));
2168:     if (row_identity && col_identity) {
2169:       B->ops->solve          = MatSolve_SeqAIJCUSPARSE_NaturalOrdering;
2170:       B->ops->solvetranspose = MatSolveTranspose_SeqAIJCUSPARSE_NaturalOrdering;
2171:     } else {
2172:       B->ops->solve          = MatSolve_SeqAIJCUSPARSE;
2173:       B->ops->solvetranspose = MatSolveTranspose_SeqAIJCUSPARSE;
2174:     }
2175: #endif
2176:   }
2177:   B->ops->matsolve          = NULL;
2178:   B->ops->matsolvetranspose = NULL;

2180:   /* get the triangular factors */
2181:   if (!cusparsestruct->use_cpu_solve) PetscCall(MatSeqAIJCUSPARSEILUAnalysisAndCopyToGPU(B));
2182:   PetscFunctionReturn(PETSC_SUCCESS);
2183: }

2185: static PetscErrorCode MatLUFactorSymbolic_SeqAIJCUSPARSE(Mat B, Mat A, IS isrow, IS iscol, const MatFactorInfo *info)
2186: {
2187:   Mat_SeqAIJCUSPARSETriFactors *cusparseTriFactors = static_cast<Mat_SeqAIJCUSPARSETriFactors *>(B->spptr);

2189:   PetscFunctionBegin;
2190:   PetscCall(MatSeqAIJCUSPARSETriFactors_Reset(&cusparseTriFactors));
2191:   PetscCall(MatLUFactorSymbolic_SeqAIJ(B, A, isrow, iscol, info));
2192:   B->ops->lufactornumeric = MatLUFactorNumeric_SeqAIJCUSPARSE;
2193:   PetscFunctionReturn(PETSC_SUCCESS);
2194: }

2196: static PetscErrorCode MatILUFactorSymbolic_SeqAIJCUSPARSE(Mat B, Mat A, IS isrow, IS iscol, const MatFactorInfo *info)
2197: {
2198:   Mat_SeqAIJCUSPARSETriFactors *cusparseTriFactors = (Mat_SeqAIJCUSPARSETriFactors *)B->spptr;

2200:   PetscFunctionBegin;
2201: #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
2202:   PetscBool row_identity = PETSC_FALSE, col_identity = PETSC_FALSE;
2203:   if (!info->factoronhost) {
2204:     PetscCall(ISIdentity(isrow, &row_identity));
2205:     PetscCall(ISIdentity(iscol, &col_identity));
2206:   }
2207:   if (!info->levels && row_identity && col_identity) {
2208:     PetscCall(MatILUFactorSymbolic_SeqAIJCUSPARSE_ILU0(B, A, isrow, iscol, info));
2209:   } else
2210: #endif
2211:   {
2212:     PetscCall(MatSeqAIJCUSPARSETriFactors_Reset(&cusparseTriFactors));
2213:     PetscCall(MatILUFactorSymbolic_SeqAIJ(B, A, isrow, iscol, info));
2214:     B->ops->lufactornumeric = MatLUFactorNumeric_SeqAIJCUSPARSE;
2215:   }
2216:   PetscFunctionReturn(PETSC_SUCCESS);
2217: }

2219: static PetscErrorCode MatICCFactorSymbolic_SeqAIJCUSPARSE(Mat B, Mat A, IS perm, const MatFactorInfo *info)
2220: {
2221:   Mat_SeqAIJCUSPARSETriFactors *cusparseTriFactors = (Mat_SeqAIJCUSPARSETriFactors *)B->spptr;

2223:   PetscFunctionBegin;
2224: #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
2225:   PetscBool perm_identity = PETSC_FALSE;
2226:   if (!info->factoronhost) PetscCall(ISIdentity(perm, &perm_identity));
2227:   if (!info->levels && perm_identity) {
2228:     PetscCall(MatICCFactorSymbolic_SeqAIJCUSPARSE_ICC0(B, A, perm, info));
2229:   } else
2230: #endif
2231:   {
2232:     PetscCall(MatSeqAIJCUSPARSETriFactors_Reset(&cusparseTriFactors));
2233:     PetscCall(MatICCFactorSymbolic_SeqAIJ(B, A, perm, info));
2234:     B->ops->choleskyfactornumeric = MatCholeskyFactorNumeric_SeqAIJCUSPARSE;
2235:   }
2236:   PetscFunctionReturn(PETSC_SUCCESS);
2237: }

2239: static PetscErrorCode MatCholeskyFactorSymbolic_SeqAIJCUSPARSE(Mat B, Mat A, IS perm, const MatFactorInfo *info)
2240: {
2241:   Mat_SeqAIJCUSPARSETriFactors *cusparseTriFactors = (Mat_SeqAIJCUSPARSETriFactors *)B->spptr;

2243:   PetscFunctionBegin;
2244:   PetscCall(MatSeqAIJCUSPARSETriFactors_Reset(&cusparseTriFactors));
2245:   PetscCall(MatCholeskyFactorSymbolic_SeqAIJ(B, A, perm, info));
2246:   B->ops->choleskyfactornumeric = MatCholeskyFactorNumeric_SeqAIJCUSPARSE;
2247:   PetscFunctionReturn(PETSC_SUCCESS);
2248: }

2250: static PetscErrorCode MatFactorGetSolverType_seqaij_cusparse(Mat, MatSolverType *type)
2251: {
2252:   PetscFunctionBegin;
2253:   *type = MATSOLVERCUSPARSE;
2254:   PetscFunctionReturn(PETSC_SUCCESS);
2255: }

2257: /*MC
2258:   MATSOLVERCUSPARSE = "cusparse" - A matrix type providing triangular solvers for seq matrices
2259:   on a single GPU of type, `MATSEQAIJCUSPARSE`. Currently supported
2260:   algorithms are ILU(k) and ICC(k). Typically, deeper factorizations (larger k) results in poorer
2261:   performance in the triangular solves. Full LU, and Cholesky decompositions can be solved through the
2262:   CuSPARSE triangular solve algorithm. However, the performance can be quite poor and thus these
2263:   algorithms are not recommended. This class does NOT support direct solver operations.

2265:   Level: beginner

2267: .seealso: [](ch_matrices), `Mat`, `MATSEQAIJCUSPARSE`, `PCFactorSetMatSolverType()`, `MatSolverType`, `MatCreateSeqAIJCUSPARSE()`,
2268:           `MATAIJCUSPARSE`, `MatCreateAIJCUSPARSE()`, `MatCUSPARSESetFormat()`, `MatCUSPARSEStorageFormat`, `MatCUSPARSEFormatOperation`
2269: M*/

2271: PETSC_EXTERN PetscErrorCode MatGetFactor_seqaijcusparse_cusparse(Mat A, MatFactorType ftype, Mat *B)
2272: {
2273:   PetscInt n = A->rmap->n;

2275:   PetscFunctionBegin;
2276:   PetscCall(MatCreate(PetscObjectComm((PetscObject)A), B));
2277:   PetscCall(MatSetSizes(*B, n, n, n, n));
2278:   (*B)->factortype = ftype; // factortype makes MatSetType() allocate spptr of type Mat_SeqAIJCUSPARSETriFactors
2279:   PetscCall(MatSetType(*B, MATSEQAIJCUSPARSE));

2281:   if (A->boundtocpu && A->bindingpropagates) PetscCall(MatBindToCPU(*B, PETSC_TRUE));
2282:   if (ftype == MAT_FACTOR_LU || ftype == MAT_FACTOR_ILU || ftype == MAT_FACTOR_ILUDT) {
2283:     PetscCall(MatSetBlockSizesFromMats(*B, A, A));
2284:     if (!A->boundtocpu) {
2285:       (*B)->ops->ilufactorsymbolic = MatILUFactorSymbolic_SeqAIJCUSPARSE;
2286:       (*B)->ops->lufactorsymbolic  = MatLUFactorSymbolic_SeqAIJCUSPARSE;
2287:     } else {
2288:       (*B)->ops->ilufactorsymbolic = MatILUFactorSymbolic_SeqAIJ;
2289:       (*B)->ops->lufactorsymbolic  = MatLUFactorSymbolic_SeqAIJ;
2290:     }
2291:     PetscCall(PetscStrallocpy(MATORDERINGND, (char **)&(*B)->preferredordering[MAT_FACTOR_LU]));
2292:     PetscCall(PetscStrallocpy(MATORDERINGNATURAL, (char **)&(*B)->preferredordering[MAT_FACTOR_ILU]));
2293:     PetscCall(PetscStrallocpy(MATORDERINGNATURAL, (char **)&(*B)->preferredordering[MAT_FACTOR_ILUDT]));
2294:   } else if (ftype == MAT_FACTOR_CHOLESKY || ftype == MAT_FACTOR_ICC) {
2295:     if (!A->boundtocpu) {
2296:       (*B)->ops->iccfactorsymbolic      = MatICCFactorSymbolic_SeqAIJCUSPARSE;
2297:       (*B)->ops->choleskyfactorsymbolic = MatCholeskyFactorSymbolic_SeqAIJCUSPARSE;
2298:     } else {
2299:       (*B)->ops->iccfactorsymbolic      = MatICCFactorSymbolic_SeqAIJ;
2300:       (*B)->ops->choleskyfactorsymbolic = MatCholeskyFactorSymbolic_SeqAIJ;
2301:     }
2302:     PetscCall(PetscStrallocpy(MATORDERINGND, (char **)&(*B)->preferredordering[MAT_FACTOR_CHOLESKY]));
2303:     PetscCall(PetscStrallocpy(MATORDERINGNATURAL, (char **)&(*B)->preferredordering[MAT_FACTOR_ICC]));
2304:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "Factor type not supported for CUSPARSE Matrix Types");

2306:   PetscCall(MatSeqAIJSetPreallocation(*B, MAT_SKIP_ALLOCATION, NULL));
2307:   (*B)->canuseordering = PETSC_TRUE;
2308:   PetscCall(PetscObjectComposeFunction((PetscObject)*B, "MatFactorGetSolverType_C", MatFactorGetSolverType_seqaij_cusparse));
2309:   PetscFunctionReturn(PETSC_SUCCESS);
2310: }

2312: static PetscErrorCode MatSeqAIJCUSPARSECopyFromGPU(Mat A)
2313: {
2314:   Mat_SeqAIJ         *a    = (Mat_SeqAIJ *)A->data;
2315:   Mat_SeqAIJCUSPARSE *cusp = (Mat_SeqAIJCUSPARSE *)A->spptr;
2316: #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
2317:   Mat_SeqAIJCUSPARSETriFactors *fs = (Mat_SeqAIJCUSPARSETriFactors *)A->spptr;
2318: #endif

2320:   PetscFunctionBegin;
2321:   if (A->offloadmask == PETSC_OFFLOAD_GPU) {
2322:     PetscCall(PetscLogEventBegin(MAT_CUSPARSECopyFromGPU, A, 0, 0, 0));
2323:     if (A->factortype == MAT_FACTOR_NONE) {
2324:       CsrMatrix *matrix = (CsrMatrix *)cusp->mat->mat;
2325:       PetscCallCUDA(cudaMemcpy(a->a, matrix->values->data().get(), a->nz * sizeof(PetscScalar), cudaMemcpyDeviceToHost));
2326:     }
2327: #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
2328:     else if (fs->csrVal) {
2329:       /* We have a factorized matrix on device and are able to copy it to host */
2330:       PetscCallCUDA(cudaMemcpy(a->a, fs->csrVal, a->nz * sizeof(PetscScalar), cudaMemcpyDeviceToHost));
2331:     }
2332: #endif
2333:     else
2334:       SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "No support for copying this type of factorized matrix from device to host");
2335:     PetscCall(PetscLogGpuToCpu(a->nz * sizeof(PetscScalar)));
2336:     PetscCall(PetscLogEventEnd(MAT_CUSPARSECopyFromGPU, A, 0, 0, 0));
2337:     A->offloadmask = PETSC_OFFLOAD_BOTH;
2338:   }
2339:   PetscFunctionReturn(PETSC_SUCCESS);
2340: }

2342: static PetscErrorCode MatSeqAIJGetArray_SeqAIJCUSPARSE(Mat A, PetscScalar *array[])
2343: {
2344:   PetscFunctionBegin;
2345:   PetscCall(MatSeqAIJCUSPARSECopyFromGPU(A));
2346:   *array = ((Mat_SeqAIJ *)A->data)->a;
2347:   PetscFunctionReturn(PETSC_SUCCESS);
2348: }

2350: static PetscErrorCode MatSeqAIJRestoreArray_SeqAIJCUSPARSE(Mat A, PetscScalar *array[])
2351: {
2352:   PetscFunctionBegin;
2353:   A->offloadmask = PETSC_OFFLOAD_CPU;
2354:   *array         = NULL;
2355:   PetscFunctionReturn(PETSC_SUCCESS);
2356: }

2358: static PetscErrorCode MatSeqAIJGetArrayRead_SeqAIJCUSPARSE(Mat A, const PetscScalar *array[])
2359: {
2360:   PetscFunctionBegin;
2361:   PetscCall(MatSeqAIJCUSPARSECopyFromGPU(A));
2362:   *array = ((Mat_SeqAIJ *)A->data)->a;
2363:   PetscFunctionReturn(PETSC_SUCCESS);
2364: }

2366: static PetscErrorCode MatSeqAIJRestoreArrayRead_SeqAIJCUSPARSE(Mat, const PetscScalar *array[])
2367: {
2368:   PetscFunctionBegin;
2369:   *array = NULL;
2370:   PetscFunctionReturn(PETSC_SUCCESS);
2371: }

2373: static PetscErrorCode MatSeqAIJGetArrayWrite_SeqAIJCUSPARSE(Mat A, PetscScalar *array[])
2374: {
2375:   PetscFunctionBegin;
2376:   *array = ((Mat_SeqAIJ *)A->data)->a;
2377:   PetscFunctionReturn(PETSC_SUCCESS);
2378: }

2380: static PetscErrorCode MatSeqAIJRestoreArrayWrite_SeqAIJCUSPARSE(Mat A, PetscScalar *array[])
2381: {
2382:   PetscFunctionBegin;
2383:   A->offloadmask = PETSC_OFFLOAD_CPU;
2384:   *array         = NULL;
2385:   PetscFunctionReturn(PETSC_SUCCESS);
2386: }

2388: static PetscErrorCode MatSeqAIJGetCSRAndMemType_SeqAIJCUSPARSE(Mat A, const PetscInt **i, const PetscInt **j, PetscScalar **a, PetscMemType *mtype)
2389: {
2390:   Mat_SeqAIJCUSPARSE *cusp;
2391:   CsrMatrix          *matrix;

2393:   PetscFunctionBegin;
2394:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));
2395:   PetscCheck(A->factortype == MAT_FACTOR_NONE, PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONGSTATE, "Not for factored matrix");
2396:   cusp = static_cast<Mat_SeqAIJCUSPARSE *>(A->spptr);
2397:   PetscCheck(cusp != NULL, PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONGSTATE, "cusp is NULL");
2398:   matrix = (CsrMatrix *)cusp->mat->mat;

2400:   if (i) {
2401: #if !defined(PETSC_USE_64BIT_INDICES)
2402:     *i = matrix->row_offsets->data().get();
2403: #else
2404:     SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "cuSparse does not supported 64-bit indices");
2405: #endif
2406:   }
2407:   if (j) {
2408: #if !defined(PETSC_USE_64BIT_INDICES)
2409:     *j = matrix->column_indices->data().get();
2410: #else
2411:     SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "cuSparse does not supported 64-bit indices");
2412: #endif
2413:   }
2414:   if (a) *a = matrix->values->data().get();
2415:   if (mtype) *mtype = PETSC_MEMTYPE_CUDA;
2416:   PetscFunctionReturn(PETSC_SUCCESS);
2417: }

2419: PETSC_INTERN PetscErrorCode MatSeqAIJCUSPARSECopyToGPU(Mat A)
2420: {
2421:   Mat_SeqAIJCUSPARSE           *cusparsestruct = (Mat_SeqAIJCUSPARSE *)A->spptr;
2422:   Mat_SeqAIJCUSPARSEMultStruct *matstruct      = cusparsestruct->mat;
2423:   Mat_SeqAIJ                   *a              = (Mat_SeqAIJ *)A->data;
2424:   PetscInt                      m              = A->rmap->n, *ii, *ridx, tmp;
2425:   cusparseStatus_t              stat;
2426:   PetscBool                     both = PETSC_TRUE;

2428:   PetscFunctionBegin;
2429:   PetscCheck(!A->boundtocpu, PETSC_COMM_SELF, PETSC_ERR_GPU, "Cannot copy to GPU");
2430:   if (A->offloadmask == PETSC_OFFLOAD_UNALLOCATED || A->offloadmask == PETSC_OFFLOAD_CPU) {
2431:     if (A->nonzerostate == cusparsestruct->nonzerostate && cusparsestruct->format == MAT_CUSPARSE_CSR) { /* Copy values only */
2432:       CsrMatrix *matrix;
2433:       matrix = (CsrMatrix *)cusparsestruct->mat->mat;

2435:       PetscCheck(!a->nz || a->a, PETSC_COMM_SELF, PETSC_ERR_GPU, "Missing CSR values");
2436:       PetscCall(PetscLogEventBegin(MAT_CUSPARSECopyToGPU, A, 0, 0, 0));
2437:       matrix->values->assign(a->a, a->a + a->nz);
2438:       PetscCallCUDA(WaitForCUDA());
2439:       PetscCall(PetscLogCpuToGpu(a->nz * sizeof(PetscScalar)));
2440:       PetscCall(PetscLogEventEnd(MAT_CUSPARSECopyToGPU, A, 0, 0, 0));
2441:       PetscCall(MatSeqAIJCUSPARSEInvalidateTranspose(A, PETSC_FALSE));
2442:     } else {
2443:       PetscInt nnz;
2444:       PetscCall(PetscLogEventBegin(MAT_CUSPARSECopyToGPU, A, 0, 0, 0));
2445:       PetscCall(MatSeqAIJCUSPARSEMultStruct_Destroy(&cusparsestruct->mat, cusparsestruct->format));
2446:       PetscCall(MatSeqAIJCUSPARSEInvalidateTranspose(A, PETSC_TRUE));
2447:       delete cusparsestruct->workVector;
2448:       delete cusparsestruct->rowoffsets_gpu;
2449:       cusparsestruct->workVector     = NULL;
2450:       cusparsestruct->rowoffsets_gpu = NULL;
2451:       try {
2452:         if (a->compressedrow.use) {
2453:           m    = a->compressedrow.nrows;
2454:           ii   = a->compressedrow.i;
2455:           ridx = a->compressedrow.rindex;
2456:         } else {
2457:           m    = A->rmap->n;
2458:           ii   = a->i;
2459:           ridx = NULL;
2460:         }
2461:         PetscCheck(ii, PETSC_COMM_SELF, PETSC_ERR_GPU, "Missing CSR row data");
2462:         if (!a->a) {
2463:           nnz  = ii[m];
2464:           both = PETSC_FALSE;
2465:         } else nnz = a->nz;
2466:         PetscCheck(!nnz || a->j, PETSC_COMM_SELF, PETSC_ERR_GPU, "Missing CSR column data");

2468:         /* create cusparse matrix */
2469:         cusparsestruct->nrows = m;
2470:         matstruct             = new Mat_SeqAIJCUSPARSEMultStruct;
2471:         PetscCallCUSPARSE(cusparseCreateMatDescr(&matstruct->descr));
2472:         PetscCallCUSPARSE(cusparseSetMatIndexBase(matstruct->descr, CUSPARSE_INDEX_BASE_ZERO));
2473:         PetscCallCUSPARSE(cusparseSetMatType(matstruct->descr, CUSPARSE_MATRIX_TYPE_GENERAL));

2475:         PetscCallCUDA(cudaMalloc((void **)&matstruct->alpha_one, sizeof(PetscScalar)));
2476:         PetscCallCUDA(cudaMalloc((void **)&matstruct->beta_zero, sizeof(PetscScalar)));
2477:         PetscCallCUDA(cudaMalloc((void **)&matstruct->beta_one, sizeof(PetscScalar)));
2478:         PetscCallCUDA(cudaMemcpy(matstruct->alpha_one, &PETSC_CUSPARSE_ONE, sizeof(PetscScalar), cudaMemcpyHostToDevice));
2479:         PetscCallCUDA(cudaMemcpy(matstruct->beta_zero, &PETSC_CUSPARSE_ZERO, sizeof(PetscScalar), cudaMemcpyHostToDevice));
2480:         PetscCallCUDA(cudaMemcpy(matstruct->beta_one, &PETSC_CUSPARSE_ONE, sizeof(PetscScalar), cudaMemcpyHostToDevice));
2481:         PetscCallCUSPARSE(cusparseSetPointerMode(cusparsestruct->handle, CUSPARSE_POINTER_MODE_DEVICE));

2483:         /* Build a hybrid/ellpack matrix if this option is chosen for the storage */
2484:         if (cusparsestruct->format == MAT_CUSPARSE_CSR) {
2485:           /* set the matrix */
2486:           CsrMatrix *mat   = new CsrMatrix;
2487:           mat->num_rows    = m;
2488:           mat->num_cols    = A->cmap->n;
2489:           mat->num_entries = nnz;
2490:           PetscCallCXX(mat->row_offsets = new THRUSTINTARRAY32(m + 1));
2491:           mat->row_offsets->assign(ii, ii + m + 1);
2492:           PetscCallCXX(mat->column_indices = new THRUSTINTARRAY32(nnz));
2493:           mat->column_indices->assign(a->j, a->j + nnz);

2495:           PetscCallCXX(mat->values = new THRUSTARRAY(nnz));
2496:           if (a->a) mat->values->assign(a->a, a->a + nnz);

2498:           /* assign the pointer */
2499:           matstruct->mat = mat;
2500: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
2501:           if (mat->num_rows) { /* cusparse errors on empty matrices! */
2502:             stat = cusparseCreateCsr(&matstruct->matDescr, mat->num_rows, mat->num_cols, mat->num_entries, mat->row_offsets->data().get(), mat->column_indices->data().get(), mat->values->data().get(), CUSPARSE_INDEX_32I, CUSPARSE_INDEX_32I, /* row offset, col idx types due to THRUSTINTARRAY32 */
2503:                                      CUSPARSE_INDEX_BASE_ZERO, cusparse_scalartype);
2504:             PetscCallCUSPARSE(stat);
2505:           }
2506: #endif
2507:         } else if (cusparsestruct->format == MAT_CUSPARSE_ELL || cusparsestruct->format == MAT_CUSPARSE_HYB) {
2508: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
2509:           SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "MAT_CUSPARSE_ELL and MAT_CUSPARSE_HYB are not supported since CUDA-11.0");
2510: #else
2511:           CsrMatrix *mat   = new CsrMatrix;
2512:           mat->num_rows    = m;
2513:           mat->num_cols    = A->cmap->n;
2514:           mat->num_entries = nnz;
2515:           PetscCallCXX(mat->row_offsets = new THRUSTINTARRAY32(m + 1));
2516:           mat->row_offsets->assign(ii, ii + m + 1);

2518:           PetscCallCXX(mat->column_indices = new THRUSTINTARRAY32(nnz));
2519:           mat->column_indices->assign(a->j, a->j + nnz);

2521:           PetscCallCXX(mat->values = new THRUSTARRAY(nnz));
2522:           if (a->a) mat->values->assign(a->a, a->a + nnz);

2524:           cusparseHybMat_t hybMat;
2525:           PetscCallCUSPARSE(cusparseCreateHybMat(&hybMat));
2526:           cusparseHybPartition_t partition = cusparsestruct->format == MAT_CUSPARSE_ELL ? CUSPARSE_HYB_PARTITION_MAX : CUSPARSE_HYB_PARTITION_AUTO;
2527:           stat                             = cusparse_csr2hyb(cusparsestruct->handle, mat->num_rows, mat->num_cols, matstruct->descr, mat->values->data().get(), mat->row_offsets->data().get(), mat->column_indices->data().get(), hybMat, 0, partition);
2528:           PetscCallCUSPARSE(stat);
2529:           /* assign the pointer */
2530:           matstruct->mat = hybMat;

2532:           if (mat) {
2533:             if (mat->values) delete (THRUSTARRAY *)mat->values;
2534:             if (mat->column_indices) delete (THRUSTINTARRAY32 *)mat->column_indices;
2535:             if (mat->row_offsets) delete (THRUSTINTARRAY32 *)mat->row_offsets;
2536:             delete (CsrMatrix *)mat;
2537:           }
2538: #endif
2539:         }

2541:         /* assign the compressed row indices */
2542:         if (a->compressedrow.use) {
2543:           PetscCallCXX(cusparsestruct->workVector = new THRUSTARRAY(m));
2544:           PetscCallCXX(matstruct->cprowIndices = new THRUSTINTARRAY(m));
2545:           matstruct->cprowIndices->assign(ridx, ridx + m);
2546:           tmp = m;
2547:         } else {
2548:           cusparsestruct->workVector = NULL;
2549:           matstruct->cprowIndices    = NULL;
2550:           tmp                        = 0;
2551:         }
2552:         PetscCall(PetscLogCpuToGpu(((m + 1) + (a->nz)) * sizeof(int) + tmp * sizeof(PetscInt) + (3 + (a->nz)) * sizeof(PetscScalar)));

2554:         /* assign the pointer */
2555:         cusparsestruct->mat = matstruct;
2556:       } catch (char *ex) {
2557:         SETERRQ(PETSC_COMM_SELF, PETSC_ERR_LIB, "CUSPARSE error: %s", ex);
2558:       }
2559:       PetscCallCUDA(WaitForCUDA());
2560:       PetscCall(PetscLogEventEnd(MAT_CUSPARSECopyToGPU, A, 0, 0, 0));
2561:       cusparsestruct->nonzerostate = A->nonzerostate;
2562:     }
2563:     if (both) A->offloadmask = PETSC_OFFLOAD_BOTH;
2564:   }
2565:   PetscFunctionReturn(PETSC_SUCCESS);
2566: }

2568: struct VecCUDAPlusEquals {
2569:   template <typename Tuple>
2570:   __host__ __device__ void operator()(Tuple t)
2571:   {
2572:     thrust::get<1>(t) = thrust::get<1>(t) + thrust::get<0>(t);
2573:   }
2574: };

2576: struct VecCUDAEquals {
2577:   template <typename Tuple>
2578:   __host__ __device__ void operator()(Tuple t)
2579:   {
2580:     thrust::get<1>(t) = thrust::get<0>(t);
2581:   }
2582: };

2584: struct VecCUDAEqualsReverse {
2585:   template <typename Tuple>
2586:   __host__ __device__ void operator()(Tuple t)
2587:   {
2588:     thrust::get<0>(t) = thrust::get<1>(t);
2589:   }
2590: };

2592: struct MatProductCtx_MatMatCusparse {
2593:   PetscBool      cisdense;
2594:   PetscScalar   *Bt;
2595:   Mat            X;
2596:   PetscBool      reusesym; /* Cusparse does not have split symbolic and numeric phases for sparse matmat operations */
2597:   PetscLogDouble flops;
2598:   CsrMatrix     *Bcsr;

2600: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
2601:   cusparseSpMatDescr_t matSpBDescr;
2602:   PetscBool            initialized; /* C = alpha op(A) op(B) + beta C */
2603:   cusparseDnMatDescr_t matBDescr;
2604:   cusparseDnMatDescr_t matCDescr;
2605:   PetscInt             Blda, Clda; /* Record leading dimensions of B and C here to detect changes*/
2606:   #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
2607:   void *dBuffer4;
2608:   void *dBuffer5;
2609:   #endif
2610:   size_t                mmBufferSize;
2611:   void                 *mmBuffer;
2612:   void                 *mmBuffer2; /* SpGEMM WorkEstimation buffer */
2613:   cusparseSpGEMMDescr_t spgemmDesc;
2614: #endif
2615: };

2617: static PetscErrorCode MatProductCtxDestroy_MatMatCusparse(void **data)
2618: {
2619:   MatProductCtx_MatMatCusparse *mmdata = *(MatProductCtx_MatMatCusparse **)data;

2621:   PetscFunctionBegin;
2622:   PetscCallCUDA(cudaFree(mmdata->Bt));
2623:   delete mmdata->Bcsr;
2624: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
2625:   if (mmdata->matSpBDescr) PetscCallCUSPARSE(cusparseDestroySpMat(mmdata->matSpBDescr));
2626:   if (mmdata->matBDescr) PetscCallCUSPARSE(cusparseDestroyDnMat(mmdata->matBDescr));
2627:   if (mmdata->matCDescr) PetscCallCUSPARSE(cusparseDestroyDnMat(mmdata->matCDescr));
2628:   if (mmdata->spgemmDesc) PetscCallCUSPARSE(cusparseSpGEMM_destroyDescr(mmdata->spgemmDesc));
2629:   #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
2630:   if (mmdata->dBuffer4) PetscCallCUDA(cudaFree(mmdata->dBuffer4));
2631:   if (mmdata->dBuffer5) PetscCallCUDA(cudaFree(mmdata->dBuffer5));
2632:   #endif
2633:   if (mmdata->mmBuffer) PetscCallCUDA(cudaFree(mmdata->mmBuffer));
2634:   if (mmdata->mmBuffer2) PetscCallCUDA(cudaFree(mmdata->mmBuffer2));
2635: #endif
2636:   PetscCall(MatDestroy(&mmdata->X));
2637:   PetscCall(PetscFree(*data));
2638:   PetscFunctionReturn(PETSC_SUCCESS);
2639: }

2641: #include <../src/mat/impls/dense/seq/dense.h>

2643: static PetscErrorCode MatProductNumeric_SeqAIJCUSPARSE_SeqDENSECUDA(Mat C)
2644: {
2645:   Mat_Product                  *product = C->product;
2646:   Mat                           A, B;
2647:   PetscInt                      m, n, blda, clda;
2648:   PetscBool                     flg, biscuda;
2649:   Mat_SeqAIJCUSPARSE           *cusp;
2650:   cusparseStatus_t              stat;
2651:   cusparseOperation_t           opA;
2652:   const PetscScalar            *barray;
2653:   PetscScalar                  *carray;
2654:   MatProductCtx_MatMatCusparse *mmdata;
2655:   Mat_SeqAIJCUSPARSEMultStruct *mat;
2656:   CsrMatrix                    *csrmat;

2658:   PetscFunctionBegin;
2659:   MatCheckProduct(C, 1);
2660:   PetscCheck(C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Product data empty");
2661:   mmdata = (MatProductCtx_MatMatCusparse *)product->data;
2662:   A      = product->A;
2663:   B      = product->B;
2664:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATSEQAIJCUSPARSE, &flg));
2665:   PetscCheck(flg, PetscObjectComm((PetscObject)A), PETSC_ERR_GPU, "Not for type %s", ((PetscObject)A)->type_name);
2666:   /* currently CopyToGpu does not copy if the matrix is bound to CPU
2667:      Instead of silently accepting the wrong answer, I prefer to raise the error */
2668:   PetscCheck(!A->boundtocpu, PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONG, "Cannot bind to CPU a CUSPARSE matrix between MatProductSymbolic and MatProductNumeric phases");
2669:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));
2670:   cusp = (Mat_SeqAIJCUSPARSE *)A->spptr;
2671:   switch (product->type) {
2672:   case MATPRODUCT_AB:
2673:   case MATPRODUCT_PtAP:
2674:     mat = cusp->mat;
2675:     opA = CUSPARSE_OPERATION_NON_TRANSPOSE;
2676:     m   = A->rmap->n;
2677:     n   = B->cmap->n;
2678:     break;
2679:   case MATPRODUCT_AtB:
2680:     if (!A->form_explicit_transpose) {
2681:       mat = cusp->mat;
2682:       opA = CUSPARSE_OPERATION_TRANSPOSE;
2683:     } else {
2684:       PetscCall(MatSeqAIJCUSPARSEFormExplicitTranspose(A));
2685:       mat = cusp->matTranspose;
2686:       opA = CUSPARSE_OPERATION_NON_TRANSPOSE;
2687:     }
2688:     m = A->cmap->n;
2689:     n = B->cmap->n;
2690:     break;
2691:   case MATPRODUCT_ABt:
2692:   case MATPRODUCT_RARt:
2693:     mat = cusp->mat;
2694:     opA = CUSPARSE_OPERATION_NON_TRANSPOSE;
2695:     m   = A->rmap->n;
2696:     n   = B->rmap->n;
2697:     break;
2698:   default:
2699:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Unsupported product type %s", MatProductTypes[product->type]);
2700:   }
2701:   PetscCheck(mat, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Missing Mat_SeqAIJCUSPARSEMultStruct");
2702:   csrmat = (CsrMatrix *)mat->mat;
2703:   /* if the user passed a CPU matrix, copy the data to the GPU */
2704:   PetscCall(PetscObjectTypeCompare((PetscObject)B, MATSEQDENSECUDA, &biscuda));
2705:   if (!biscuda) PetscCall(MatConvert(B, MATSEQDENSECUDA, MAT_INPLACE_MATRIX, &B));
2706:   PetscCall(MatDenseGetArrayReadAndMemType(B, &barray, nullptr));

2708:   PetscCall(MatDenseGetLDA(B, &blda));
2709:   if (product->type == MATPRODUCT_RARt || product->type == MATPRODUCT_PtAP) {
2710:     PetscCall(MatDenseGetArrayWriteAndMemType(mmdata->X, &carray, nullptr));
2711:     PetscCall(MatDenseGetLDA(mmdata->X, &clda));
2712:   } else {
2713:     PetscCall(MatDenseGetArrayWriteAndMemType(C, &carray, nullptr));
2714:     PetscCall(MatDenseGetLDA(C, &clda));
2715:   }

2717:   PetscCall(PetscLogGpuTimeBegin());
2718: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
2719:   cusparseOperation_t opB = (product->type == MATPRODUCT_ABt || product->type == MATPRODUCT_RARt) ? CUSPARSE_OPERATION_TRANSPOSE : CUSPARSE_OPERATION_NON_TRANSPOSE;
2720:   #if PETSC_PKG_CUDA_VERSION_GE(12, 4, 0)
2721:   cusparseSpMatDescr_t &matADescr = mat->matDescr_SpMM[opA];
2722:   #else
2723:   cusparseSpMatDescr_t &matADescr = mat->matDescr;
2724:   #endif

2726:   /* (re)allocate mmBuffer if not initialized or LDAs are different */
2727:   if (!mmdata->initialized || mmdata->Blda != blda || mmdata->Clda != clda) {
2728:     size_t mmBufferSize;
2729:     if (mmdata->initialized && mmdata->Blda != blda) {
2730:       PetscCallCUSPARSE(cusparseDestroyDnMat(mmdata->matBDescr));
2731:       mmdata->matBDescr = NULL;
2732:     }
2733:     if (!mmdata->matBDescr) {
2734:       PetscCallCUSPARSE(cusparseCreateDnMat(&mmdata->matBDescr, B->rmap->n, B->cmap->n, blda, (void *)barray, cusparse_scalartype, CUSPARSE_ORDER_COL));
2735:       mmdata->Blda = blda;
2736:     }

2738:     if (mmdata->initialized && mmdata->Clda != clda) {
2739:       PetscCallCUSPARSE(cusparseDestroyDnMat(mmdata->matCDescr));
2740:       mmdata->matCDescr = NULL;
2741:     }
2742:     if (!mmdata->matCDescr) { /* matCDescr is for C or mmdata->X */
2743:       PetscCallCUSPARSE(cusparseCreateDnMat(&mmdata->matCDescr, m, n, clda, (void *)carray, cusparse_scalartype, CUSPARSE_ORDER_COL));
2744:       mmdata->Clda = clda;
2745:     }

2747:   #if PETSC_PKG_CUDA_VERSION_GE(12, 4, 0) // tested up to 12.6.0
2748:     if (matADescr) {
2749:       PetscCallCUSPARSE(cusparseDestroySpMat(matADescr)); // Because I find I could not reuse matADescr. It could be a cusparse bug
2750:       matADescr = NULL;
2751:     }
2752:   #endif

2754:     if (!matADescr) {
2755:       stat = cusparseCreateCsr(&matADescr, csrmat->num_rows, csrmat->num_cols, csrmat->num_entries, csrmat->row_offsets->data().get(), csrmat->column_indices->data().get(), csrmat->values->data().get(), CUSPARSE_INDEX_32I, CUSPARSE_INDEX_32I, /* row offset, col idx types due to THRUSTINTARRAY32 */
2756:                                CUSPARSE_INDEX_BASE_ZERO, cusparse_scalartype);
2757:       PetscCallCUSPARSE(stat);
2758:     }

2760:     PetscCallCUSPARSE(cusparseSpMM_bufferSize(cusp->handle, opA, opB, mat->alpha_one, matADescr, mmdata->matBDescr, mat->beta_zero, mmdata->matCDescr, cusparse_scalartype, cusp->spmmAlg, &mmBufferSize));

2762:     if ((mmdata->mmBuffer && mmdata->mmBufferSize < mmBufferSize) || !mmdata->mmBuffer) {
2763:       PetscCallCUDA(cudaFree(mmdata->mmBuffer));
2764:       PetscCallCUDA(cudaMalloc(&mmdata->mmBuffer, mmBufferSize));
2765:       mmdata->mmBufferSize = mmBufferSize;
2766:     }

2768:   #if PETSC_PKG_CUDA_VERSION_GE(12, 4, 0) // the _preprocess was added in 11.2.1, but PETSc worked without it until 12.4.0
2769:     PetscCallCUSPARSE(cusparseSpMM_preprocess(cusp->handle, opA, opB, mat->alpha_one, matADescr, mmdata->matBDescr, mat->beta_zero, mmdata->matCDescr, cusparse_scalartype, cusp->spmmAlg, mmdata->mmBuffer));
2770:   #endif

2772:     mmdata->initialized = PETSC_TRUE;
2773:   } else {
2774:     /* to be safe, always update pointers of the mats */
2775:     PetscCallCUSPARSE(cusparseSpMatSetValues(matADescr, csrmat->values->data().get()));
2776:     PetscCallCUSPARSE(cusparseDnMatSetValues(mmdata->matBDescr, (void *)barray));
2777:     PetscCallCUSPARSE(cusparseDnMatSetValues(mmdata->matCDescr, (void *)carray));
2778:   }

2780:   /* do cusparseSpMM, which supports transpose on B */
2781:   PetscCallCUSPARSE(cusparseSpMM(cusp->handle, opA, opB, mat->alpha_one, matADescr, mmdata->matBDescr, mat->beta_zero, mmdata->matCDescr, cusparse_scalartype, cusp->spmmAlg, mmdata->mmBuffer));
2782: #else
2783:   PetscInt k;
2784:   /* cusparseXcsrmm does not support transpose on B */
2785:   if (product->type == MATPRODUCT_ABt || product->type == MATPRODUCT_RARt) {
2786:     cublasHandle_t cublasv2handle;
2787:     cublasStatus_t cerr;

2789:     PetscCall(PetscCUBLASGetHandle(&cublasv2handle));
2790:     cerr = cublasXgeam(cublasv2handle, CUBLAS_OP_T, CUBLAS_OP_T, B->cmap->n, B->rmap->n, &PETSC_CUSPARSE_ONE, barray, blda, &PETSC_CUSPARSE_ZERO, barray, blda, mmdata->Bt, B->cmap->n);
2791:     PetscCallCUBLAS(cerr);
2792:     blda = B->cmap->n;
2793:     k    = B->cmap->n;
2794:   } else {
2795:     k = B->rmap->n;
2796:   }

2798:   /* perform the MatMat operation, op(A) is m x k, op(B) is k x n */
2799:   stat = cusparse_csr_spmm(cusp->handle, opA, m, n, k, csrmat->num_entries, mat->alpha_one, mat->descr, csrmat->values->data().get(), csrmat->row_offsets->data().get(), csrmat->column_indices->data().get(), mmdata->Bt ? mmdata->Bt : barray, blda, mat->beta_zero, carray, clda);
2800:   PetscCallCUSPARSE(stat);
2801: #endif
2802:   PetscCall(PetscLogGpuTimeEnd());
2803:   PetscCall(PetscLogGpuFlops(n * 2.0 * csrmat->num_entries));
2804:   PetscCall(MatDenseRestoreArrayReadAndMemType(B, &barray));
2805:   if (product->type == MATPRODUCT_RARt) {
2806:     PetscCall(MatDenseRestoreArrayWriteAndMemType(mmdata->X, &carray));
2807:     PetscCall(MatMatMultNumeric_SeqDenseCUDA_SeqDenseCUDA_Internal(B, mmdata->X, C, PETSC_FALSE, PETSC_FALSE));
2808:   } else if (product->type == MATPRODUCT_PtAP) {
2809:     PetscCall(MatDenseRestoreArrayWriteAndMemType(mmdata->X, &carray));
2810:     PetscCall(MatMatMultNumeric_SeqDenseCUDA_SeqDenseCUDA_Internal(B, mmdata->X, C, PETSC_TRUE, PETSC_FALSE));
2811:   } else {
2812:     PetscCall(MatDenseRestoreArrayWriteAndMemType(C, &carray));
2813:   }
2814:   if (mmdata->cisdense) PetscCall(MatConvert(C, MATSEQDENSE, MAT_INPLACE_MATRIX, &C));
2815:   if (!biscuda) PetscCall(MatConvert(B, MATSEQDENSE, MAT_INPLACE_MATRIX, &B));
2816:   PetscFunctionReturn(PETSC_SUCCESS);
2817: }

2819: static PetscErrorCode MatProductSymbolic_SeqAIJCUSPARSE_SeqDENSECUDA(Mat C)
2820: {
2821:   Mat_Product                  *product = C->product;
2822:   Mat                           A, B;
2823:   PetscInt                      m, n;
2824:   PetscBool                     cisdense, flg;
2825:   MatProductCtx_MatMatCusparse *mmdata;
2826:   Mat_SeqAIJCUSPARSE           *cusp;

2828:   PetscFunctionBegin;
2829:   MatCheckProduct(C, 1);
2830:   PetscCheck(!C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Product data not empty");
2831:   A = product->A;
2832:   B = product->B;
2833:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATSEQAIJCUSPARSE, &flg));
2834:   PetscCheck(flg, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Not for type %s", ((PetscObject)A)->type_name);
2835:   cusp = (Mat_SeqAIJCUSPARSE *)A->spptr;
2836:   PetscCheck(cusp->format == MAT_CUSPARSE_CSR, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Only for MAT_CUSPARSE_CSR format");
2837:   switch (product->type) {
2838:   case MATPRODUCT_AB:
2839:     m = A->rmap->n;
2840:     n = B->cmap->n;
2841:     PetscCall(MatSetBlockSizesFromMats(C, A, B));
2842:     break;
2843:   case MATPRODUCT_AtB:
2844:     m = A->cmap->n;
2845:     n = B->cmap->n;
2846:     if (A->cmap->bs > 0) PetscCall(PetscLayoutSetBlockSize(C->rmap, A->cmap->bs));
2847:     if (B->cmap->bs > 0) PetscCall(PetscLayoutSetBlockSize(C->cmap, B->cmap->bs));
2848:     break;
2849:   case MATPRODUCT_ABt:
2850:     m = A->rmap->n;
2851:     n = B->rmap->n;
2852:     if (A->rmap->bs > 0) PetscCall(PetscLayoutSetBlockSize(C->rmap, A->rmap->bs));
2853:     if (B->rmap->bs > 0) PetscCall(PetscLayoutSetBlockSize(C->cmap, B->rmap->bs));
2854:     break;
2855:   case MATPRODUCT_PtAP:
2856:     m = B->cmap->n;
2857:     n = B->cmap->n;
2858:     if (B->cmap->bs > 0) PetscCall(PetscLayoutSetBlockSize(C->rmap, B->cmap->bs));
2859:     if (B->cmap->bs > 0) PetscCall(PetscLayoutSetBlockSize(C->cmap, B->cmap->bs));
2860:     break;
2861:   case MATPRODUCT_RARt:
2862:     m = B->rmap->n;
2863:     n = B->rmap->n;
2864:     if (B->rmap->bs > 0) PetscCall(PetscLayoutSetBlockSize(C->rmap, B->rmap->bs));
2865:     if (B->rmap->bs > 0) PetscCall(PetscLayoutSetBlockSize(C->cmap, B->rmap->bs));
2866:     break;
2867:   default:
2868:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Unsupported product type %s", MatProductTypes[product->type]);
2869:   }
2870:   PetscCall(MatSetSizes(C, m, n, m, n));
2871:   /* if C is of type MATSEQDENSE (CPU), perform the operation on the GPU and then copy on the CPU */
2872:   PetscCall(PetscObjectTypeCompare((PetscObject)C, MATSEQDENSE, &cisdense));
2873:   PetscCall(MatSetType(C, MATSEQDENSECUDA));

2875:   /* product data */
2876:   PetscCall(PetscNew(&mmdata));
2877:   mmdata->cisdense = cisdense;
2878: #if PETSC_PKG_CUDA_VERSION_LT(11, 0, 0)
2879:   /* cusparseXcsrmm does not support transpose on B, so we allocate buffer to store B^T */
2880:   if (product->type == MATPRODUCT_ABt || product->type == MATPRODUCT_RARt) PetscCallCUDA(cudaMalloc((void **)&mmdata->Bt, (size_t)B->rmap->n * (size_t)B->cmap->n * sizeof(PetscScalar)));
2881: #endif
2882:   /* for these products we need intermediate storage */
2883:   if (product->type == MATPRODUCT_RARt || product->type == MATPRODUCT_PtAP) {
2884:     PetscCall(MatCreate(PetscObjectComm((PetscObject)C), &mmdata->X));
2885:     PetscCall(MatSetType(mmdata->X, MATSEQDENSECUDA));
2886:     if (product->type == MATPRODUCT_RARt) { /* do not preallocate, since the first call to MatDenseCUDAGetArray will preallocate on the GPU for us */
2887:       PetscCall(MatSetSizes(mmdata->X, A->rmap->n, B->rmap->n, A->rmap->n, B->rmap->n));
2888:     } else {
2889:       PetscCall(MatSetSizes(mmdata->X, A->rmap->n, B->cmap->n, A->rmap->n, B->cmap->n));
2890:     }
2891:   }
2892:   C->product->data    = mmdata;
2893:   C->product->destroy = MatProductCtxDestroy_MatMatCusparse;

2895:   C->ops->productnumeric = MatProductNumeric_SeqAIJCUSPARSE_SeqDENSECUDA;
2896:   PetscFunctionReturn(PETSC_SUCCESS);
2897: }

2899: static PetscErrorCode MatProductNumeric_SeqAIJCUSPARSE_SeqAIJCUSPARSE(Mat C)
2900: {
2901:   Mat_Product                  *product = C->product;
2902:   Mat                           A, B;
2903:   Mat_SeqAIJCUSPARSE           *Acusp, *Bcusp, *Ccusp;
2904:   Mat_SeqAIJ                   *c = (Mat_SeqAIJ *)C->data;
2905:   Mat_SeqAIJCUSPARSEMultStruct *Amat, *Bmat, *Cmat;
2906:   CsrMatrix                    *Acsr, *Bcsr, *Ccsr;
2907:   PetscBool                     flg;
2908:   cusparseStatus_t              stat;
2909:   MatProductType                ptype;
2910:   MatProductCtx_MatMatCusparse *mmdata;
2911: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
2912:   cusparseSpMatDescr_t BmatSpDescr;
2913: #endif
2914:   cusparseOperation_t opA = CUSPARSE_OPERATION_NON_TRANSPOSE, opB = CUSPARSE_OPERATION_NON_TRANSPOSE; /* cuSPARSE spgemm doesn't support transpose yet */

2916:   PetscFunctionBegin;
2917:   MatCheckProduct(C, 1);
2918:   PetscCheck(C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Product data empty");
2919:   PetscCall(PetscObjectTypeCompare((PetscObject)C, MATSEQAIJCUSPARSE, &flg));
2920:   PetscCheck(flg, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Not for C of type %s", ((PetscObject)C)->type_name);
2921:   mmdata = (MatProductCtx_MatMatCusparse *)C->product->data;
2922:   A      = product->A;
2923:   B      = product->B;
2924:   if (mmdata->reusesym) { /* this happens when api_user is true, meaning that the matrix values have been already computed in the MatProductSymbolic phase */
2925:     mmdata->reusesym = PETSC_FALSE;
2926:     Ccusp            = (Mat_SeqAIJCUSPARSE *)C->spptr;
2927:     PetscCheck(Ccusp->format == MAT_CUSPARSE_CSR, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Only for MAT_CUSPARSE_CSR format");
2928:     Cmat = Ccusp->mat;
2929:     PetscCheck(Cmat, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Missing C mult struct for product type %s", MatProductTypes[C->product->type]);
2930:     Ccsr = (CsrMatrix *)Cmat->mat;
2931:     PetscCheck(Ccsr, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Missing C CSR struct");
2932:     goto finalize;
2933:   }
2934:   if (!c->nz) goto finalize;
2935:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATSEQAIJCUSPARSE, &flg));
2936:   PetscCheck(flg, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Not for type %s", ((PetscObject)A)->type_name);
2937:   PetscCall(PetscObjectTypeCompare((PetscObject)B, MATSEQAIJCUSPARSE, &flg));
2938:   PetscCheck(flg, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Not for B of type %s", ((PetscObject)B)->type_name);
2939:   PetscCheck(!A->boundtocpu, PetscObjectComm((PetscObject)C), PETSC_ERR_ARG_WRONG, "Cannot bind to CPU a CUSPARSE matrix between MatProductSymbolic and MatProductNumeric phases");
2940:   PetscCheck(!B->boundtocpu, PetscObjectComm((PetscObject)C), PETSC_ERR_ARG_WRONG, "Cannot bind to CPU a CUSPARSE matrix between MatProductSymbolic and MatProductNumeric phases");
2941:   Acusp = (Mat_SeqAIJCUSPARSE *)A->spptr;
2942:   Bcusp = (Mat_SeqAIJCUSPARSE *)B->spptr;
2943:   Ccusp = (Mat_SeqAIJCUSPARSE *)C->spptr;
2944:   PetscCheck(Acusp->format == MAT_CUSPARSE_CSR, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Only for MAT_CUSPARSE_CSR format");
2945:   PetscCheck(Bcusp->format == MAT_CUSPARSE_CSR, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Only for MAT_CUSPARSE_CSR format");
2946:   PetscCheck(Ccusp->format == MAT_CUSPARSE_CSR, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Only for MAT_CUSPARSE_CSR format");
2947:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));
2948:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(B));

2950:   ptype = product->type;
2951:   if (A->symmetric == PETSC_BOOL3_TRUE && ptype == MATPRODUCT_AtB) {
2952:     ptype = MATPRODUCT_AB;
2953:     PetscCheck(product->symbolic_used_the_fact_A_is_symmetric, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Symbolic should have been built using the fact that A is symmetric");
2954:   }
2955:   if (B->symmetric == PETSC_BOOL3_TRUE && ptype == MATPRODUCT_ABt) {
2956:     ptype = MATPRODUCT_AB;
2957:     PetscCheck(product->symbolic_used_the_fact_B_is_symmetric, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Symbolic should have been built using the fact that B is symmetric");
2958:   }
2959:   switch (ptype) {
2960:   case MATPRODUCT_AB:
2961:     Amat = Acusp->mat;
2962:     Bmat = Bcusp->mat;
2963:     break;
2964:   case MATPRODUCT_AtB:
2965:     Amat = Acusp->matTranspose;
2966:     Bmat = Bcusp->mat;
2967:     break;
2968:   case MATPRODUCT_ABt:
2969:     Amat = Acusp->mat;
2970:     Bmat = Bcusp->matTranspose;
2971:     break;
2972:   default:
2973:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Unsupported product type %s", MatProductTypes[product->type]);
2974:   }
2975:   Cmat = Ccusp->mat;
2976:   PetscCheck(Amat, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Missing A mult struct for product type %s", MatProductTypes[ptype]);
2977:   PetscCheck(Bmat, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Missing B mult struct for product type %s", MatProductTypes[ptype]);
2978:   PetscCheck(Cmat, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Missing C mult struct for product type %s", MatProductTypes[ptype]);
2979:   Acsr = (CsrMatrix *)Amat->mat;
2980:   Bcsr = mmdata->Bcsr ? mmdata->Bcsr : (CsrMatrix *)Bmat->mat; /* B may be in compressed row storage */
2981:   Ccsr = (CsrMatrix *)Cmat->mat;
2982:   PetscCheck(Acsr, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Missing A CSR struct");
2983:   PetscCheck(Bcsr, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Missing B CSR struct");
2984:   PetscCheck(Ccsr, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Missing C CSR struct");
2985:   PetscCall(PetscLogGpuTimeBegin());
2986: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
2987:   BmatSpDescr = mmdata->Bcsr ? mmdata->matSpBDescr : Bmat->matDescr; /* B may be in compressed row storage */
2988:   PetscCallCUSPARSE(cusparseSetPointerMode(Ccusp->handle, CUSPARSE_POINTER_MODE_DEVICE));
2989:   #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
2990:   stat = cusparseSpGEMMreuse_compute(Ccusp->handle, opA, opB, Cmat->alpha_one, Amat->matDescr, BmatSpDescr, Cmat->beta_zero, Cmat->matDescr, cusparse_scalartype, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc);
2991:   PetscCallCUSPARSE(stat);
2992:   #else
2993:   stat = cusparseSpGEMM_compute(Ccusp->handle, opA, opB, Cmat->alpha_one, Amat->matDescr, BmatSpDescr, Cmat->beta_zero, Cmat->matDescr, cusparse_scalartype, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc, &mmdata->mmBufferSize, mmdata->mmBuffer);
2994:   PetscCallCUSPARSE(stat);
2995:   stat = cusparseSpGEMM_copy(Ccusp->handle, opA, opB, Cmat->alpha_one, Amat->matDescr, BmatSpDescr, Cmat->beta_zero, Cmat->matDescr, cusparse_scalartype, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc);
2996:   PetscCallCUSPARSE(stat);
2997:   #endif
2998: #else
2999:   stat = cusparse_csr_spgemm(Ccusp->handle, opA, opB, Acsr->num_rows, Bcsr->num_cols, Acsr->num_cols, Amat->descr, Acsr->num_entries, Acsr->values->data().get(), Acsr->row_offsets->data().get(), Acsr->column_indices->data().get(), Bmat->descr, Bcsr->num_entries,
3000:                              Bcsr->values->data().get(), Bcsr->row_offsets->data().get(), Bcsr->column_indices->data().get(), Cmat->descr, Ccsr->values->data().get(), Ccsr->row_offsets->data().get(), Ccsr->column_indices->data().get());
3001:   PetscCallCUSPARSE(stat);
3002: #endif
3003:   PetscCall(PetscLogGpuFlops(mmdata->flops));
3004:   PetscCallCUDA(WaitForCUDA());
3005:   PetscCall(PetscLogGpuTimeEnd());
3006:   C->offloadmask = PETSC_OFFLOAD_GPU;
3007: finalize:
3008:   /* shorter version of MatAssemblyEnd_SeqAIJ */
3009:   PetscCall(PetscInfo(C, "Matrix size: %" PetscInt_FMT " X %" PetscInt_FMT "; storage space: 0 unneeded, %" PetscInt_FMT " used\n", C->rmap->n, C->cmap->n, c->nz));
3010:   PetscCall(PetscInfo(C, "Number of mallocs during MatSetValues() is 0\n"));
3011:   PetscCall(PetscInfo(C, "Maximum nonzeros in any row is %" PetscInt_FMT "\n", c->rmax));
3012:   c->reallocs = 0;
3013:   C->info.mallocs += 0;
3014:   C->info.nz_unneeded = 0;
3015:   C->assembled = C->was_assembled = PETSC_TRUE;
3016:   C->num_ass++;
3017:   PetscFunctionReturn(PETSC_SUCCESS);
3018: }

3020: static PetscErrorCode MatProductSymbolic_SeqAIJCUSPARSE_SeqAIJCUSPARSE(Mat C)
3021: {
3022:   Mat_Product                  *product = C->product;
3023:   Mat                           A, B;
3024:   Mat_SeqAIJCUSPARSE           *Acusp, *Bcusp, *Ccusp;
3025:   Mat_SeqAIJ                   *a, *b, *c;
3026:   Mat_SeqAIJCUSPARSEMultStruct *Amat, *Bmat, *Cmat;
3027:   CsrMatrix                    *Acsr, *Bcsr, *Ccsr;
3028:   PetscInt                      i, j, m, n, k;
3029:   PetscBool                     flg;
3030:   cusparseStatus_t              stat;
3031:   MatProductType                ptype;
3032:   MatProductCtx_MatMatCusparse *mmdata;
3033:   PetscLogDouble                flops;
3034:   PetscBool                     biscompressed, ciscompressed;
3035: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
3036:   int64_t              C_num_rows1, C_num_cols1, C_nnz1;
3037:   cusparseSpMatDescr_t BmatSpDescr;
3038: #else
3039:   int cnz;
3040: #endif
3041:   cusparseOperation_t opA = CUSPARSE_OPERATION_NON_TRANSPOSE, opB = CUSPARSE_OPERATION_NON_TRANSPOSE; /* cuSPARSE spgemm doesn't support transpose yet */

3043:   PetscFunctionBegin;
3044:   MatCheckProduct(C, 1);
3045:   PetscCheck(!C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Product data not empty");
3046:   A = product->A;
3047:   B = product->B;
3048:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATSEQAIJCUSPARSE, &flg));
3049:   PetscCheck(flg, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Not for type %s", ((PetscObject)A)->type_name);
3050:   PetscCall(PetscObjectTypeCompare((PetscObject)B, MATSEQAIJCUSPARSE, &flg));
3051:   PetscCheck(flg, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Not for B of type %s", ((PetscObject)B)->type_name);
3052:   a = (Mat_SeqAIJ *)A->data;
3053:   b = (Mat_SeqAIJ *)B->data;
3054:   /* product data */
3055:   PetscCall(PetscNew(&mmdata));
3056:   C->product->data    = mmdata;
3057:   C->product->destroy = MatProductCtxDestroy_MatMatCusparse;

3059:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));
3060:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(B));
3061:   Acusp = (Mat_SeqAIJCUSPARSE *)A->spptr; /* Access spptr after MatSeqAIJCUSPARSECopyToGPU, not before */
3062:   Bcusp = (Mat_SeqAIJCUSPARSE *)B->spptr;
3063:   PetscCheck(Acusp->format == MAT_CUSPARSE_CSR, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Only for MAT_CUSPARSE_CSR format");
3064:   PetscCheck(Bcusp->format == MAT_CUSPARSE_CSR, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Only for MAT_CUSPARSE_CSR format");

3066:   ptype = product->type;
3067:   if (A->symmetric == PETSC_BOOL3_TRUE && ptype == MATPRODUCT_AtB) {
3068:     ptype                                          = MATPRODUCT_AB;
3069:     product->symbolic_used_the_fact_A_is_symmetric = PETSC_TRUE;
3070:   }
3071:   if (B->symmetric == PETSC_BOOL3_TRUE && ptype == MATPRODUCT_ABt) {
3072:     ptype                                          = MATPRODUCT_AB;
3073:     product->symbolic_used_the_fact_B_is_symmetric = PETSC_TRUE;
3074:   }
3075:   biscompressed = PETSC_FALSE;
3076:   ciscompressed = PETSC_FALSE;
3077:   switch (ptype) {
3078:   case MATPRODUCT_AB:
3079:     m    = A->rmap->n;
3080:     n    = B->cmap->n;
3081:     k    = A->cmap->n;
3082:     Amat = Acusp->mat;
3083:     Bmat = Bcusp->mat;
3084:     if (a->compressedrow.use) ciscompressed = PETSC_TRUE;
3085:     if (b->compressedrow.use) biscompressed = PETSC_TRUE;
3086:     break;
3087:   case MATPRODUCT_AtB:
3088:     m = A->cmap->n;
3089:     n = B->cmap->n;
3090:     k = A->rmap->n;
3091:     PetscCall(MatSeqAIJCUSPARSEFormExplicitTranspose(A));
3092:     Amat = Acusp->matTranspose;
3093:     Bmat = Bcusp->mat;
3094:     if (b->compressedrow.use) biscompressed = PETSC_TRUE;
3095:     break;
3096:   case MATPRODUCT_ABt:
3097:     m = A->rmap->n;
3098:     n = B->rmap->n;
3099:     k = A->cmap->n;
3100:     PetscCall(MatSeqAIJCUSPARSEFormExplicitTranspose(B));
3101:     Amat = Acusp->mat;
3102:     Bmat = Bcusp->matTranspose;
3103:     if (a->compressedrow.use) ciscompressed = PETSC_TRUE;
3104:     break;
3105:   default:
3106:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Unsupported product type %s", MatProductTypes[product->type]);
3107:   }

3109:   /* create cusparse matrix */
3110:   PetscCall(MatSetSizes(C, m, n, m, n));
3111:   PetscCall(MatSetType(C, MATSEQAIJCUSPARSE));
3112:   c     = (Mat_SeqAIJ *)C->data;
3113:   Ccusp = (Mat_SeqAIJCUSPARSE *)C->spptr;
3114:   Cmat  = new Mat_SeqAIJCUSPARSEMultStruct;
3115:   Ccsr  = new CsrMatrix;

3117:   c->compressedrow.use = ciscompressed;
3118:   if (c->compressedrow.use) { /* if a is in compressed row, than c will be in compressed row format */
3119:     c->compressedrow.nrows = a->compressedrow.nrows;
3120:     PetscCall(PetscMalloc2(c->compressedrow.nrows + 1, &c->compressedrow.i, c->compressedrow.nrows, &c->compressedrow.rindex));
3121:     PetscCall(PetscArraycpy(c->compressedrow.rindex, a->compressedrow.rindex, c->compressedrow.nrows));
3122:     Ccusp->workVector  = new THRUSTARRAY(c->compressedrow.nrows);
3123:     Cmat->cprowIndices = new THRUSTINTARRAY(c->compressedrow.nrows);
3124:     Cmat->cprowIndices->assign(c->compressedrow.rindex, c->compressedrow.rindex + c->compressedrow.nrows);
3125:   } else {
3126:     c->compressedrow.nrows  = 0;
3127:     c->compressedrow.i      = NULL;
3128:     c->compressedrow.rindex = NULL;
3129:     Ccusp->workVector       = NULL;
3130:     Cmat->cprowIndices      = NULL;
3131:   }
3132:   Ccusp->nrows      = ciscompressed ? c->compressedrow.nrows : m;
3133:   Ccusp->mat        = Cmat;
3134:   Ccusp->mat->mat   = Ccsr;
3135:   Ccsr->num_rows    = Ccusp->nrows;
3136:   Ccsr->num_cols    = n;
3137:   Ccsr->row_offsets = new THRUSTINTARRAY32(Ccusp->nrows + 1);
3138:   PetscCallCUSPARSE(cusparseCreateMatDescr(&Cmat->descr));
3139:   PetscCallCUSPARSE(cusparseSetMatIndexBase(Cmat->descr, CUSPARSE_INDEX_BASE_ZERO));
3140:   PetscCallCUSPARSE(cusparseSetMatType(Cmat->descr, CUSPARSE_MATRIX_TYPE_GENERAL));
3141:   PetscCallCUDA(cudaMalloc((void **)&Cmat->alpha_one, sizeof(PetscScalar)));
3142:   PetscCallCUDA(cudaMalloc((void **)&Cmat->beta_zero, sizeof(PetscScalar)));
3143:   PetscCallCUDA(cudaMalloc((void **)&Cmat->beta_one, sizeof(PetscScalar)));
3144:   PetscCallCUDA(cudaMemcpy(Cmat->alpha_one, &PETSC_CUSPARSE_ONE, sizeof(PetscScalar), cudaMemcpyHostToDevice));
3145:   PetscCallCUDA(cudaMemcpy(Cmat->beta_zero, &PETSC_CUSPARSE_ZERO, sizeof(PetscScalar), cudaMemcpyHostToDevice));
3146:   PetscCallCUDA(cudaMemcpy(Cmat->beta_one, &PETSC_CUSPARSE_ONE, sizeof(PetscScalar), cudaMemcpyHostToDevice));
3147:   if (!Ccsr->num_rows || !Ccsr->num_cols || !a->nz || !b->nz) { /* cusparse raise errors in different calls when matrices have zero rows/columns! */
3148:     PetscCallThrust(thrust::fill(thrust::device, Ccsr->row_offsets->begin(), Ccsr->row_offsets->end(), 0));
3149:     c->nz                = 0;
3150:     Ccsr->column_indices = new THRUSTINTARRAY32(c->nz);
3151:     Ccsr->values         = new THRUSTARRAY(c->nz);
3152:     goto finalizesym;
3153:   }

3155:   PetscCheck(Amat, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Missing A mult struct for product type %s", MatProductTypes[ptype]);
3156:   PetscCheck(Bmat, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Missing B mult struct for product type %s", MatProductTypes[ptype]);
3157:   Acsr = (CsrMatrix *)Amat->mat;
3158:   if (!biscompressed) {
3159:     Bcsr = (CsrMatrix *)Bmat->mat;
3160: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
3161:     BmatSpDescr = Bmat->matDescr;
3162: #endif
3163:   } else { /* we need to use row offsets for the full matrix */
3164:     CsrMatrix *cBcsr     = (CsrMatrix *)Bmat->mat;
3165:     Bcsr                 = new CsrMatrix;
3166:     Bcsr->num_rows       = B->rmap->n;
3167:     Bcsr->num_cols       = cBcsr->num_cols;
3168:     Bcsr->num_entries    = cBcsr->num_entries;
3169:     Bcsr->column_indices = cBcsr->column_indices;
3170:     Bcsr->values         = cBcsr->values;
3171:     if (!Bcusp->rowoffsets_gpu) {
3172:       Bcusp->rowoffsets_gpu = new THRUSTINTARRAY32(B->rmap->n + 1);
3173:       Bcusp->rowoffsets_gpu->assign(b->i, b->i + B->rmap->n + 1);
3174:       PetscCall(PetscLogCpuToGpu((B->rmap->n + 1) * sizeof(PetscInt)));
3175:     }
3176:     Bcsr->row_offsets = Bcusp->rowoffsets_gpu;
3177:     mmdata->Bcsr      = Bcsr;
3178: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
3179:     if (Bcsr->num_rows && Bcsr->num_cols) {
3180:       stat = cusparseCreateCsr(&mmdata->matSpBDescr, Bcsr->num_rows, Bcsr->num_cols, Bcsr->num_entries, Bcsr->row_offsets->data().get(), Bcsr->column_indices->data().get(), Bcsr->values->data().get(), CUSPARSE_INDEX_32I, CUSPARSE_INDEX_32I, CUSPARSE_INDEX_BASE_ZERO, cusparse_scalartype);
3181:       PetscCallCUSPARSE(stat);
3182:     }
3183:     BmatSpDescr = mmdata->matSpBDescr;
3184: #endif
3185:   }
3186:   PetscCheck(Acsr, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Missing A CSR struct");
3187:   PetscCheck(Bcsr, PetscObjectComm((PetscObject)C), PETSC_ERR_GPU, "Missing B CSR struct");
3188:   /* precompute flops count */
3189:   if (ptype == MATPRODUCT_AB) {
3190:     for (i = 0, flops = 0; i < A->rmap->n; i++) {
3191:       const PetscInt st = a->i[i];
3192:       const PetscInt en = a->i[i + 1];
3193:       for (j = st; j < en; j++) {
3194:         const PetscInt brow = a->j[j];
3195:         flops += 2. * (b->i[brow + 1] - b->i[brow]);
3196:       }
3197:     }
3198:   } else if (ptype == MATPRODUCT_AtB) {
3199:     for (i = 0, flops = 0; i < A->rmap->n; i++) {
3200:       const PetscInt anzi = a->i[i + 1] - a->i[i];
3201:       const PetscInt bnzi = b->i[i + 1] - b->i[i];
3202:       flops += (2. * anzi) * bnzi;
3203:     }
3204:   } else { /* TODO */
3205:     flops = 0.;
3206:   }

3208:   mmdata->flops = flops;
3209:   PetscCall(PetscLogGpuTimeBegin());

3211: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
3212:   PetscCallCUSPARSE(cusparseSetPointerMode(Ccusp->handle, CUSPARSE_POINTER_MODE_DEVICE));
3213:   // cuda-12.2 requires non-null csrRowOffsets
3214:   stat = cusparseCreateCsr(&Cmat->matDescr, Ccsr->num_rows, Ccsr->num_cols, 0, Ccsr->row_offsets->data().get(), NULL, NULL, CUSPARSE_INDEX_32I, CUSPARSE_INDEX_32I, CUSPARSE_INDEX_BASE_ZERO, cusparse_scalartype);
3215:   PetscCallCUSPARSE(stat);
3216:   PetscCallCUSPARSE(cusparseSpGEMM_createDescr(&mmdata->spgemmDesc));
3217:   #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
3218:   {
3219:     /* cusparseSpGEMMreuse has more reasonable APIs than cusparseSpGEMM, so we prefer to use it.
3220:      We follow the sample code at https://github.com/NVIDIA/CUDALibrarySamples/blob/master/cuSPARSE/spgemm_reuse
3221:   */
3222:     void *dBuffer1 = NULL;
3223:     void *dBuffer2 = NULL;
3224:     void *dBuffer3 = NULL;
3225:     /* dBuffer4, dBuffer5 are needed by cusparseSpGEMMreuse_compute, and therefore are stored in mmdata */
3226:     size_t bufferSize1 = 0;
3227:     size_t bufferSize2 = 0;
3228:     size_t bufferSize3 = 0;
3229:     size_t bufferSize4 = 0;
3230:     size_t bufferSize5 = 0;

3232:     /* ask bufferSize1 bytes for external memory */
3233:     stat = cusparseSpGEMMreuse_workEstimation(Ccusp->handle, opA, opB, Amat->matDescr, BmatSpDescr, Cmat->matDescr, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc, &bufferSize1, NULL);
3234:     PetscCallCUSPARSE(stat);
3235:     PetscCallCUDA(cudaMalloc((void **)&dBuffer1, bufferSize1));
3236:     /* inspect the matrices A and B to understand the memory requirement for the next step */
3237:     stat = cusparseSpGEMMreuse_workEstimation(Ccusp->handle, opA, opB, Amat->matDescr, BmatSpDescr, Cmat->matDescr, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc, &bufferSize1, dBuffer1);
3238:     PetscCallCUSPARSE(stat);

3240:     stat = cusparseSpGEMMreuse_nnz(Ccusp->handle, opA, opB, Amat->matDescr, BmatSpDescr, Cmat->matDescr, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc, &bufferSize2, NULL, &bufferSize3, NULL, &bufferSize4, NULL);
3241:     PetscCallCUSPARSE(stat);
3242:     PetscCallCUDA(cudaMalloc((void **)&dBuffer2, bufferSize2));
3243:     PetscCallCUDA(cudaMalloc((void **)&dBuffer3, bufferSize3));
3244:     PetscCallCUDA(cudaMalloc((void **)&mmdata->dBuffer4, bufferSize4));
3245:     stat = cusparseSpGEMMreuse_nnz(Ccusp->handle, opA, opB, Amat->matDescr, BmatSpDescr, Cmat->matDescr, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc, &bufferSize2, dBuffer2, &bufferSize3, dBuffer3, &bufferSize4, mmdata->dBuffer4);
3246:     PetscCallCUSPARSE(stat);
3247:     PetscCallCUDA(cudaFree(dBuffer1));
3248:     PetscCallCUDA(cudaFree(dBuffer2));

3250:     /* get matrix C non-zero entries C_nnz1 */
3251:     PetscCallCUSPARSE(cusparseSpMatGetSize(Cmat->matDescr, &C_num_rows1, &C_num_cols1, &C_nnz1));
3252:     c->nz = (PetscInt)C_nnz1;
3253:     /* allocate matrix C */
3254:     Ccsr->column_indices = new THRUSTINTARRAY32(c->nz);
3255:     PetscCallCUDA(cudaPeekAtLastError()); /* catch out of memory errors */
3256:     Ccsr->values = new THRUSTARRAY(c->nz);
3257:     PetscCallCUDA(cudaPeekAtLastError()); /* catch out of memory errors */
3258:     /* update matC with the new pointers */
3259:     stat = cusparseCsrSetPointers(Cmat->matDescr, Ccsr->row_offsets->data().get(), Ccsr->column_indices->data().get(), Ccsr->values->data().get());
3260:     PetscCallCUSPARSE(stat);

3262:     stat = cusparseSpGEMMreuse_copy(Ccusp->handle, opA, opB, Amat->matDescr, BmatSpDescr, Cmat->matDescr, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc, &bufferSize5, NULL);
3263:     PetscCallCUSPARSE(stat);
3264:     PetscCallCUDA(cudaMalloc((void **)&mmdata->dBuffer5, bufferSize5));
3265:     stat = cusparseSpGEMMreuse_copy(Ccusp->handle, opA, opB, Amat->matDescr, BmatSpDescr, Cmat->matDescr, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc, &bufferSize5, mmdata->dBuffer5);
3266:     PetscCallCUSPARSE(stat);
3267:     PetscCallCUDA(cudaFree(dBuffer3));
3268:     stat = cusparseSpGEMMreuse_compute(Ccusp->handle, opA, opB, Cmat->alpha_one, Amat->matDescr, BmatSpDescr, Cmat->beta_zero, Cmat->matDescr, cusparse_scalartype, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc);
3269:     PetscCallCUSPARSE(stat);
3270:     PetscCall(PetscInfo(C, "Buffer sizes for type %s, result %" PetscInt_FMT " x %" PetscInt_FMT " (k %" PetscInt_FMT ", nzA %" PetscInt_FMT ", nzB %" PetscInt_FMT ", nzC %" PetscInt_FMT ") are: %ldKB %ldKB\n", MatProductTypes[ptype], m, n, k, a->nz, b->nz, c->nz, bufferSize4 / 1024, bufferSize5 / 1024));
3271:   }
3272:   #else
3273:   size_t bufSize2;
3274:   /* ask bufferSize bytes for external memory */
3275:   stat = cusparseSpGEMM_workEstimation(Ccusp->handle, opA, opB, Cmat->alpha_one, Amat->matDescr, BmatSpDescr, Cmat->beta_zero, Cmat->matDescr, cusparse_scalartype, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc, &bufSize2, NULL);
3276:   PetscCallCUSPARSE(stat);
3277:   PetscCallCUDA(cudaMalloc((void **)&mmdata->mmBuffer2, bufSize2));
3278:   /* inspect the matrices A and B to understand the memory requirement for the next step */
3279:   stat = cusparseSpGEMM_workEstimation(Ccusp->handle, opA, opB, Cmat->alpha_one, Amat->matDescr, BmatSpDescr, Cmat->beta_zero, Cmat->matDescr, cusparse_scalartype, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc, &bufSize2, mmdata->mmBuffer2);
3280:   PetscCallCUSPARSE(stat);
3281:   /* ask bufferSize again bytes for external memory */
3282:   stat = cusparseSpGEMM_compute(Ccusp->handle, opA, opB, Cmat->alpha_one, Amat->matDescr, BmatSpDescr, Cmat->beta_zero, Cmat->matDescr, cusparse_scalartype, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc, &mmdata->mmBufferSize, NULL);
3283:   PetscCallCUSPARSE(stat);
3284:   /* The CUSPARSE documentation is not clear, nor the API
3285:      We need both buffers to perform the operations properly!
3286:      mmdata->mmBuffer2 does not appear anywhere in the compute/copy API
3287:      it only appears for the workEstimation stuff, but it seems it is needed in compute, so probably the address
3288:      is stored in the descriptor! What a messy API... */
3289:   PetscCallCUDA(cudaMalloc((void **)&mmdata->mmBuffer, mmdata->mmBufferSize));
3290:   /* compute the intermediate product of A * B */
3291:   stat = cusparseSpGEMM_compute(Ccusp->handle, opA, opB, Cmat->alpha_one, Amat->matDescr, BmatSpDescr, Cmat->beta_zero, Cmat->matDescr, cusparse_scalartype, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc, &mmdata->mmBufferSize, mmdata->mmBuffer);
3292:   PetscCallCUSPARSE(stat);
3293:   /* get matrix C non-zero entries C_nnz1 */
3294:   PetscCallCUSPARSE(cusparseSpMatGetSize(Cmat->matDescr, &C_num_rows1, &C_num_cols1, &C_nnz1));
3295:   c->nz = (PetscInt)C_nnz1;
3296:   PetscCall(PetscInfo(C, "Buffer sizes for type %s, result %" PetscInt_FMT " x %" PetscInt_FMT " (k %" PetscInt_FMT ", nzA %" PetscInt_FMT ", nzB %" PetscInt_FMT ", nzC %" PetscInt_FMT ") are: %ldKB %ldKB\n", MatProductTypes[ptype], m, n, k, a->nz, b->nz, c->nz, bufSize2 / 1024,
3297:                       mmdata->mmBufferSize / 1024));
3298:   Ccsr->column_indices = new THRUSTINTARRAY32(c->nz);
3299:   PetscCallCUDA(cudaPeekAtLastError()); /* catch out of memory errors */
3300:   Ccsr->values = new THRUSTARRAY(c->nz);
3301:   PetscCallCUDA(cudaPeekAtLastError()); /* catch out of memory errors */
3302:   stat = cusparseCsrSetPointers(Cmat->matDescr, Ccsr->row_offsets->data().get(), Ccsr->column_indices->data().get(), Ccsr->values->data().get());
3303:   PetscCallCUSPARSE(stat);
3304:   stat = cusparseSpGEMM_copy(Ccusp->handle, opA, opB, Cmat->alpha_one, Amat->matDescr, BmatSpDescr, Cmat->beta_zero, Cmat->matDescr, cusparse_scalartype, CUSPARSE_SPGEMM_DEFAULT, mmdata->spgemmDesc);
3305:   PetscCallCUSPARSE(stat);
3306:   #endif // PETSC_PKG_CUDA_VERSION_GE(11,4,0)
3307: #else
3308:   PetscCallCUSPARSE(cusparseSetPointerMode(Ccusp->handle, CUSPARSE_POINTER_MODE_HOST));
3309:   stat = cusparseXcsrgemmNnz(Ccusp->handle, opA, opB, Acsr->num_rows, Bcsr->num_cols, Acsr->num_cols, Amat->descr, Acsr->num_entries, Acsr->row_offsets->data().get(), Acsr->column_indices->data().get(), Bmat->descr, Bcsr->num_entries,
3310:                              Bcsr->row_offsets->data().get(), Bcsr->column_indices->data().get(), Cmat->descr, Ccsr->row_offsets->data().get(), &cnz);
3311:   PetscCallCUSPARSE(stat);
3312:   c->nz                = cnz;
3313:   Ccsr->column_indices = new THRUSTINTARRAY32(c->nz);
3314:   PetscCallCUDA(cudaPeekAtLastError()); /* catch out of memory errors */
3315:   Ccsr->values = new THRUSTARRAY(c->nz);
3316:   PetscCallCUDA(cudaPeekAtLastError()); /* catch out of memory errors */

3318:   PetscCallCUSPARSE(cusparseSetPointerMode(Ccusp->handle, CUSPARSE_POINTER_MODE_DEVICE));
3319:   /* with the old gemm interface (removed from 11.0 on) we cannot compute the symbolic factorization only.
3320:      I have tried using the gemm2 interface (alpha * A * B + beta * D), which allows to do symbolic by passing NULL for values, but it seems quite buggy when
3321:      D is NULL, despite the fact that CUSPARSE documentation claims it is supported! */
3322:   stat = cusparse_csr_spgemm(Ccusp->handle, opA, opB, Acsr->num_rows, Bcsr->num_cols, Acsr->num_cols, Amat->descr, Acsr->num_entries, Acsr->values->data().get(), Acsr->row_offsets->data().get(), Acsr->column_indices->data().get(), Bmat->descr, Bcsr->num_entries,
3323:                              Bcsr->values->data().get(), Bcsr->row_offsets->data().get(), Bcsr->column_indices->data().get(), Cmat->descr, Ccsr->values->data().get(), Ccsr->row_offsets->data().get(), Ccsr->column_indices->data().get());
3324:   PetscCallCUSPARSE(stat);
3325: #endif
3326:   PetscCall(PetscLogGpuFlops(mmdata->flops));
3327:   PetscCall(PetscLogGpuTimeEnd());
3328: finalizesym:
3329:   c->free_a = PETSC_TRUE;
3330:   PetscCall(PetscShmgetAllocateArray(c->nz, sizeof(PetscInt), (void **)&c->j));
3331:   PetscCall(PetscShmgetAllocateArray(m + 1, sizeof(PetscInt), (void **)&c->i));
3332:   c->free_ij = PETSC_TRUE;
3333:   if (PetscDefined(USE_64BIT_INDICES)) { /* 32 to 64-bit conversion on the GPU and then copy to host (lazy) */
3334:     PetscInt      *d_i = c->i;
3335:     THRUSTINTARRAY ii(Ccsr->row_offsets->size());
3336:     THRUSTINTARRAY jj(Ccsr->column_indices->size());
3337:     ii = *Ccsr->row_offsets;
3338:     jj = *Ccsr->column_indices;
3339:     if (ciscompressed) d_i = c->compressedrow.i;
3340:     PetscCallCUDA(cudaMemcpy(d_i, ii.data().get(), Ccsr->row_offsets->size() * sizeof(PetscInt), cudaMemcpyDeviceToHost));
3341:     PetscCallCUDA(cudaMemcpy(c->j, jj.data().get(), Ccsr->column_indices->size() * sizeof(PetscInt), cudaMemcpyDeviceToHost));
3342:   } else {
3343:     PetscInt *d_i = c->i;
3344:     if (ciscompressed) d_i = c->compressedrow.i;
3345:     PetscCallCUDA(cudaMemcpy(d_i, Ccsr->row_offsets->data().get(), Ccsr->row_offsets->size() * sizeof(PetscInt), cudaMemcpyDeviceToHost));
3346:     PetscCallCUDA(cudaMemcpy(c->j, Ccsr->column_indices->data().get(), Ccsr->column_indices->size() * sizeof(PetscInt), cudaMemcpyDeviceToHost));
3347:   }
3348:   if (ciscompressed) { /* need to expand host row offsets */
3349:     PetscInt r = 0;
3350:     c->i[0]    = 0;
3351:     for (k = 0; k < c->compressedrow.nrows; k++) {
3352:       const PetscInt next = c->compressedrow.rindex[k];
3353:       const PetscInt old  = c->compressedrow.i[k];
3354:       for (; r < next; r++) c->i[r + 1] = old;
3355:     }
3356:     for (; r < m; r++) c->i[r + 1] = c->compressedrow.i[c->compressedrow.nrows];
3357:   }
3358:   PetscCall(PetscLogGpuToCpu((Ccsr->column_indices->size() + Ccsr->row_offsets->size()) * sizeof(PetscInt)));
3359:   PetscCall(PetscMalloc1(m, &c->ilen));
3360:   PetscCall(PetscMalloc1(m, &c->imax));
3361:   c->maxnz         = c->nz;
3362:   c->nonzerorowcnt = 0;
3363:   c->rmax          = 0;
3364:   for (k = 0; k < m; k++) {
3365:     const PetscInt nn = c->i[k + 1] - c->i[k];
3366:     c->ilen[k] = c->imax[k] = nn;
3367:     c->nonzerorowcnt += (PetscInt)!!nn;
3368:     c->rmax = PetscMax(c->rmax, nn);
3369:   }
3370:   PetscCall(PetscMalloc1(c->nz, &c->a));
3371:   Ccsr->num_entries = c->nz;

3373:   C->nonzerostate++;
3374:   PetscCall(PetscLayoutSetUp(C->rmap));
3375:   PetscCall(PetscLayoutSetUp(C->cmap));
3376:   Ccusp->nonzerostate = C->nonzerostate;
3377:   C->offloadmask      = PETSC_OFFLOAD_UNALLOCATED;
3378:   C->preallocated     = PETSC_TRUE;
3379:   C->assembled        = PETSC_FALSE;
3380:   C->was_assembled    = PETSC_FALSE;
3381:   if (product->api_user && A->offloadmask == PETSC_OFFLOAD_BOTH && B->offloadmask == PETSC_OFFLOAD_BOTH) { /* flag the matrix C values as computed, so that the numeric phase will only call MatAssembly */
3382:     mmdata->reusesym = PETSC_TRUE;
3383:     C->offloadmask   = PETSC_OFFLOAD_GPU;
3384:   }
3385:   C->ops->productnumeric = MatProductNumeric_SeqAIJCUSPARSE_SeqAIJCUSPARSE;
3386:   PetscFunctionReturn(PETSC_SUCCESS);
3387: }

3389: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_SeqAIJ_SeqDense(Mat);

3391: /* handles sparse or dense B */
3392: static PetscErrorCode MatProductSetFromOptions_SeqAIJCUSPARSE(Mat mat)
3393: {
3394:   Mat_Product *product = mat->product;
3395:   PetscBool    isdense = PETSC_FALSE, Biscusp = PETSC_FALSE, Ciscusp = PETSC_TRUE;

3397:   PetscFunctionBegin;
3398:   MatCheckProduct(mat, 1);
3399:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)product->B, MATSEQDENSE, &isdense));
3400:   if (!product->A->boundtocpu && !product->B->boundtocpu) PetscCall(PetscObjectTypeCompare((PetscObject)product->B, MATSEQAIJCUSPARSE, &Biscusp));
3401:   if (product->type == MATPRODUCT_ABC) {
3402:     Ciscusp = PETSC_FALSE;
3403:     if (!product->C->boundtocpu) PetscCall(PetscObjectTypeCompare((PetscObject)product->C, MATSEQAIJCUSPARSE, &Ciscusp));
3404:   }
3405:   if (Biscusp && Ciscusp) { /* we can always select the CPU backend */
3406:     PetscBool usecpu = PETSC_FALSE;
3407:     switch (product->type) {
3408:     case MATPRODUCT_AB:
3409:       if (product->api_user) {
3410:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatMatMult", "Mat");
3411:         PetscCall(PetscOptionsBool("-matmatmult_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
3412:         PetscOptionsEnd();
3413:       } else {
3414:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AB", "Mat");
3415:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
3416:         PetscOptionsEnd();
3417:       }
3418:       break;
3419:     case MATPRODUCT_AtB:
3420:       if (product->api_user) {
3421:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatTransposeMatMult", "Mat");
3422:         PetscCall(PetscOptionsBool("-mattransposematmult_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
3423:         PetscOptionsEnd();
3424:       } else {
3425:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AtB", "Mat");
3426:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
3427:         PetscOptionsEnd();
3428:       }
3429:       break;
3430:     case MATPRODUCT_PtAP:
3431:       if (product->api_user) {
3432:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatPtAP", "Mat");
3433:         PetscCall(PetscOptionsBool("-matptap_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
3434:         PetscOptionsEnd();
3435:       } else {
3436:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_PtAP", "Mat");
3437:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
3438:         PetscOptionsEnd();
3439:       }
3440:       break;
3441:     case MATPRODUCT_RARt:
3442:       if (product->api_user) {
3443:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatRARt", "Mat");
3444:         PetscCall(PetscOptionsBool("-matrart_backend_cpu", "Use CPU code", "MatRARt", usecpu, &usecpu, NULL));
3445:         PetscOptionsEnd();
3446:       } else {
3447:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_RARt", "Mat");
3448:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatRARt", usecpu, &usecpu, NULL));
3449:         PetscOptionsEnd();
3450:       }
3451:       break;
3452:     case MATPRODUCT_ABC:
3453:       if (product->api_user) {
3454:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatMatMatMult", "Mat");
3455:         PetscCall(PetscOptionsBool("-matmatmatmult_backend_cpu", "Use CPU code", "MatMatMatMult", usecpu, &usecpu, NULL));
3456:         PetscOptionsEnd();
3457:       } else {
3458:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_ABC", "Mat");
3459:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatMatMatMult", usecpu, &usecpu, NULL));
3460:         PetscOptionsEnd();
3461:       }
3462:       break;
3463:     default:
3464:       break;
3465:     }
3466:     if (usecpu) Biscusp = Ciscusp = PETSC_FALSE;
3467:   }
3468:   /* dispatch */
3469:   if (isdense) {
3470:     switch (product->type) {
3471:     case MATPRODUCT_AB:
3472:     case MATPRODUCT_AtB:
3473:     case MATPRODUCT_ABt:
3474:     case MATPRODUCT_PtAP:
3475:     case MATPRODUCT_RARt:
3476:       if (product->A->boundtocpu) {
3477:         PetscCall(MatProductSetFromOptions_SeqAIJ_SeqDense(mat));
3478:       } else {
3479:         mat->ops->productsymbolic = MatProductSymbolic_SeqAIJCUSPARSE_SeqDENSECUDA;
3480:       }
3481:       break;
3482:     case MATPRODUCT_ABC:
3483:       mat->ops->productsymbolic = MatProductSymbolic_ABC_Basic;
3484:       break;
3485:     default:
3486:       break;
3487:     }
3488:   } else if (Biscusp && Ciscusp) {
3489:     switch (product->type) {
3490:     case MATPRODUCT_AB:
3491:     case MATPRODUCT_AtB:
3492:     case MATPRODUCT_ABt:
3493:       mat->ops->productsymbolic = MatProductSymbolic_SeqAIJCUSPARSE_SeqAIJCUSPARSE;
3494:       break;
3495:     case MATPRODUCT_PtAP:
3496:     case MATPRODUCT_RARt:
3497:     case MATPRODUCT_ABC:
3498:       mat->ops->productsymbolic = MatProductSymbolic_ABC_Basic;
3499:       break;
3500:     default:
3501:       break;
3502:     }
3503:   } else { /* fallback for AIJ */
3504:     PetscCall(MatProductSetFromOptions_SeqAIJ(mat));
3505:   }
3506:   PetscFunctionReturn(PETSC_SUCCESS);
3507: }

3509: static PetscErrorCode MatMult_SeqAIJCUSPARSE(Mat A, Vec xx, Vec yy)
3510: {
3511:   PetscFunctionBegin;
3512:   PetscCall(MatMultAddKernel_SeqAIJCUSPARSE(A, xx, NULL, yy, PETSC_FALSE, PETSC_FALSE));
3513:   PetscFunctionReturn(PETSC_SUCCESS);
3514: }

3516: static PetscErrorCode MatMultAdd_SeqAIJCUSPARSE(Mat A, Vec xx, Vec yy, Vec zz)
3517: {
3518:   PetscFunctionBegin;
3519:   PetscCall(MatMultAddKernel_SeqAIJCUSPARSE(A, xx, yy, zz, PETSC_FALSE, PETSC_FALSE));
3520:   PetscFunctionReturn(PETSC_SUCCESS);
3521: }

3523: static PetscErrorCode MatMultHermitianTranspose_SeqAIJCUSPARSE(Mat A, Vec xx, Vec yy)
3524: {
3525:   PetscFunctionBegin;
3526:   PetscCall(MatMultAddKernel_SeqAIJCUSPARSE(A, xx, NULL, yy, PETSC_TRUE, PETSC_TRUE));
3527:   PetscFunctionReturn(PETSC_SUCCESS);
3528: }

3530: static PetscErrorCode MatMultHermitianTransposeAdd_SeqAIJCUSPARSE(Mat A, Vec xx, Vec yy, Vec zz)
3531: {
3532:   PetscFunctionBegin;
3533:   PetscCall(MatMultAddKernel_SeqAIJCUSPARSE(A, xx, yy, zz, PETSC_TRUE, PETSC_TRUE));
3534:   PetscFunctionReturn(PETSC_SUCCESS);
3535: }

3537: static PetscErrorCode MatMultTranspose_SeqAIJCUSPARSE(Mat A, Vec xx, Vec yy)
3538: {
3539:   PetscFunctionBegin;
3540:   PetscCall(MatMultAddKernel_SeqAIJCUSPARSE(A, xx, NULL, yy, PETSC_TRUE, PETSC_FALSE));
3541:   PetscFunctionReturn(PETSC_SUCCESS);
3542: }

3544: __global__ static void ScatterAdd(PetscInt n, PetscInt *idx, const PetscScalar *x, PetscScalar *y)
3545: {
3546:   int i = blockIdx.x * blockDim.x + threadIdx.x;
3547:   if (i < n) y[idx[i]] += x[i];
3548: }

3550: /* z = op(A) x + y. If trans & !herm, op = ^T; if trans & herm, op = ^H; if !trans, op = no-op */
3551: static PetscErrorCode MatMultAddKernel_SeqAIJCUSPARSE(Mat A, Vec xx, Vec yy, Vec zz, PetscBool trans, PetscBool herm)
3552: {
3553:   Mat_SeqAIJ                   *a              = (Mat_SeqAIJ *)A->data;
3554:   Mat_SeqAIJCUSPARSE           *cusparsestruct = (Mat_SeqAIJCUSPARSE *)A->spptr;
3555:   Mat_SeqAIJCUSPARSEMultStruct *matstruct;
3556:   PetscScalar                  *xarray, *zarray, *dptr, *beta, *xptr;
3557:   cusparseOperation_t           opA = CUSPARSE_OPERATION_NON_TRANSPOSE;
3558:   PetscBool                     compressed;
3559: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
3560:   PetscInt nx, ny;
3561: #endif

3563:   PetscFunctionBegin;
3564:   PetscCheck(!herm || trans, PetscObjectComm((PetscObject)A), PETSC_ERR_GPU, "Hermitian and not transpose not supported");
3565:   if (!a->nz) {
3566:     if (yy) PetscCall(VecSeq_CUDA::Copy(yy, zz));
3567:     else PetscCall(VecSeq_CUDA::Set(zz, 0));
3568:     PetscFunctionReturn(PETSC_SUCCESS);
3569:   }
3570:   /* The line below is necessary due to the operations that modify the matrix on the CPU (axpy, scale, etc) */
3571:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));
3572:   if (!trans) {
3573:     matstruct = (Mat_SeqAIJCUSPARSEMultStruct *)cusparsestruct->mat;
3574:     PetscCheck(matstruct, PetscObjectComm((PetscObject)A), PETSC_ERR_GPU, "SeqAIJCUSPARSE does not have a 'mat' (need to fix)");
3575:   } else {
3576:     if (herm || !A->form_explicit_transpose) {
3577:       opA       = herm ? CUSPARSE_OPERATION_CONJUGATE_TRANSPOSE : CUSPARSE_OPERATION_TRANSPOSE;
3578:       matstruct = (Mat_SeqAIJCUSPARSEMultStruct *)cusparsestruct->mat;
3579:     } else {
3580:       if (!cusparsestruct->matTranspose) PetscCall(MatSeqAIJCUSPARSEFormExplicitTranspose(A));
3581:       matstruct = (Mat_SeqAIJCUSPARSEMultStruct *)cusparsestruct->matTranspose;
3582:     }
3583:   }
3584:   /* Does the matrix use compressed rows (i.e., drop zero rows)? */
3585:   compressed = matstruct->cprowIndices ? PETSC_TRUE : PETSC_FALSE;

3587:   try {
3588:     PetscCall(VecCUDAGetArrayRead(xx, (const PetscScalar **)&xarray));
3589:     if (yy == zz) PetscCall(VecCUDAGetArray(zz, &zarray)); /* read & write zz, so need to get up-to-date zarray on GPU */
3590:     else PetscCall(VecCUDAGetArrayWrite(zz, &zarray));     /* write zz, so no need to init zarray on GPU */

3592:     PetscCall(PetscLogGpuTimeBegin());
3593:     if (opA == CUSPARSE_OPERATION_NON_TRANSPOSE) {
3594:       /* z = A x + beta y.
3595:          If A is compressed (with less rows), then Ax is shorter than the full z, so we need a work vector to store Ax.
3596:          When A is non-compressed, and z = y, we can set beta=1 to compute y = Ax + y in one call.
3597:       */
3598:       xptr = xarray;
3599:       dptr = compressed ? cusparsestruct->workVector->data().get() : zarray;
3600:       beta = (yy == zz && !compressed) ? matstruct->beta_one : matstruct->beta_zero;
3601: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
3602:       /* Get length of x, y for y=Ax. ny might be shorter than the work vector's allocated length, since the work vector is
3603:           allocated to accommodate different uses. So we get the length info directly from mat.
3604:        */
3605:       if (cusparsestruct->format == MAT_CUSPARSE_CSR) {
3606:         CsrMatrix *mat = (CsrMatrix *)matstruct->mat;
3607:         nx             = mat->num_cols; // since y = Ax
3608:         ny             = mat->num_rows;
3609:       }
3610: #endif
3611:     } else {
3612:       /* z = A^T x + beta y
3613:          If A is compressed, then we need a work vector as the shorter version of x to compute A^T x.
3614:          Note A^Tx is of full length, so we set beta to 1.0 if y exists.
3615:        */
3616:       xptr = compressed ? cusparsestruct->workVector->data().get() : xarray;
3617:       dptr = zarray;
3618:       beta = yy ? matstruct->beta_one : matstruct->beta_zero;
3619:       if (compressed) { /* Scatter x to work vector */
3620:         thrust::device_ptr<PetscScalar> xarr = thrust::device_pointer_cast(xarray);

3622:         thrust::for_each(
3623: #if PetscDefined(HAVE_THRUST_ASYNC)
3624:           thrust::cuda::par.on(PetscDefaultCudaStream),
3625: #endif
3626:           thrust::make_zip_iterator(thrust::make_tuple(cusparsestruct->workVector->begin(), thrust::make_permutation_iterator(xarr, matstruct->cprowIndices->begin()))),
3627:           thrust::make_zip_iterator(thrust::make_tuple(cusparsestruct->workVector->begin(), thrust::make_permutation_iterator(xarr, matstruct->cprowIndices->begin()))) + matstruct->cprowIndices->size(), VecCUDAEqualsReverse());
3628:       }
3629: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
3630:       if (cusparsestruct->format == MAT_CUSPARSE_CSR) {
3631:         CsrMatrix *mat = (CsrMatrix *)matstruct->mat;
3632:         nx             = mat->num_rows; // since y = A^T x
3633:         ny             = mat->num_cols;
3634:       }
3635: #endif
3636:     }

3638:     /* csr_spmv does y = alpha op(A) x + beta y */
3639:     if (cusparsestruct->format == MAT_CUSPARSE_CSR) {
3640: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
3641:   #if PETSC_PKG_CUDA_VERSION_GE(12, 4, 0)
3642:       cusparseSpMatDescr_t &matDescr = matstruct->matDescr_SpMV[opA]; // All opA's should use the same matDescr, but the cusparse issue/bug (#212) after 12.4 forced us to create a new one for each opA.
3643:   #else
3644:       cusparseSpMatDescr_t &matDescr = matstruct->matDescr;
3645:   #endif

3647:       PetscCheck(opA >= 0 && opA <= 2, PETSC_COMM_SELF, PETSC_ERR_SUP, "cuSPARSE ABI on cusparseOperation_t has changed and PETSc has not been updated accordingly");
3648:   #if PETSC_PKG_CUDA_VERSION_GE(12, 4, 0)
3649:       if (!matDescr) {
3650:         CsrMatrix *mat = (CsrMatrix *)matstruct->mat;
3651:         PetscCallCUSPARSE(cusparseCreateCsr(&matDescr, mat->num_rows, mat->num_cols, mat->num_entries, mat->row_offsets->data().get(), mat->column_indices->data().get(), mat->values->data().get(), CUSPARSE_INDEX_32I, CUSPARSE_INDEX_32I, CUSPARSE_INDEX_BASE_ZERO, cusparse_scalartype));
3652:       }
3653:   #endif

3655:       if (!matstruct->cuSpMV[opA].initialized) { /* built on demand */
3656:         PetscCallCUSPARSE(cusparseCreateDnVec(&matstruct->cuSpMV[opA].vecXDescr, nx, xptr, cusparse_scalartype));
3657:         PetscCallCUSPARSE(cusparseCreateDnVec(&matstruct->cuSpMV[opA].vecYDescr, ny, dptr, cusparse_scalartype));
3658:         PetscCallCUSPARSE(
3659:           cusparseSpMV_bufferSize(cusparsestruct->handle, opA, matstruct->alpha_one, matDescr, matstruct->cuSpMV[opA].vecXDescr, beta, matstruct->cuSpMV[opA].vecYDescr, cusparse_scalartype, cusparsestruct->spmvAlg, &matstruct->cuSpMV[opA].spmvBufferSize));
3660:         PetscCallCUDA(cudaMalloc(&matstruct->cuSpMV[opA].spmvBuffer, matstruct->cuSpMV[opA].spmvBufferSize));
3661:   #if PETSC_PKG_CUDA_VERSION_GE(12, 4, 0) // cusparseSpMV_preprocess is added in 12.4
3662:         PetscCallCUSPARSE(
3663:           cusparseSpMV_preprocess(cusparsestruct->handle, opA, matstruct->alpha_one, matDescr, matstruct->cuSpMV[opA].vecXDescr, beta, matstruct->cuSpMV[opA].vecYDescr, cusparse_scalartype, cusparsestruct->spmvAlg, matstruct->cuSpMV[opA].spmvBuffer));
3664:   #endif
3665:         matstruct->cuSpMV[opA].initialized = PETSC_TRUE;
3666:       } else {
3667:         /* x, y's value pointers might change between calls, but their shape is kept, so we just update pointers */
3668:         PetscCallCUSPARSE(cusparseDnVecSetValues(matstruct->cuSpMV[opA].vecXDescr, xptr));
3669:         PetscCallCUSPARSE(cusparseDnVecSetValues(matstruct->cuSpMV[opA].vecYDescr, dptr));
3670:       }

3672:       PetscCallCUSPARSE(cusparseSpMV(cusparsestruct->handle, opA, matstruct->alpha_one, matDescr, matstruct->cuSpMV[opA].vecXDescr, beta, matstruct->cuSpMV[opA].vecYDescr, cusparse_scalartype, cusparsestruct->spmvAlg, matstruct->cuSpMV[opA].spmvBuffer));
3673: #else
3674:       CsrMatrix *mat = (CsrMatrix *)matstruct->mat;
3675:       PetscCallCUSPARSE(cusparse_csr_spmv(cusparsestruct->handle, opA, mat->num_rows, mat->num_cols, mat->num_entries, matstruct->alpha_one, matstruct->descr, mat->values->data().get(), mat->row_offsets->data().get(), mat->column_indices->data().get(), xptr, beta, dptr));
3676: #endif
3677:     } else {
3678:       if (cusparsestruct->nrows) {
3679: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
3680:         SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "MAT_CUSPARSE_ELL and MAT_CUSPARSE_HYB are not supported since CUDA-11.0");
3681: #else
3682:         cusparseHybMat_t hybMat = (cusparseHybMat_t)matstruct->mat;
3683:         PetscCallCUSPARSE(cusparse_hyb_spmv(cusparsestruct->handle, opA, matstruct->alpha_one, matstruct->descr, hybMat, xptr, beta, dptr));
3684: #endif
3685:       }
3686:     }
3687:     PetscCall(PetscLogGpuTimeEnd());

3689:     if (opA == CUSPARSE_OPERATION_NON_TRANSPOSE) {
3690:       if (yy) {                                      /* MatMultAdd: zz = A*xx + yy */
3691:         if (compressed) {                            /* A is compressed. We first copy yy to zz, then ScatterAdd the work vector to zz */
3692:           PetscCall(VecSeq_CUDA::Copy(yy, zz));      /* zz = yy */
3693:         } else if (zz != yy) {                       /* A is not compressed. zz already contains A*xx, and we just need to add yy */
3694:           PetscCall(VecSeq_CUDA::AXPY(zz, 1.0, yy)); /* zz += yy */
3695:         }
3696:       } else if (compressed) { /* MatMult: zz = A*xx. A is compressed, so we zero zz first, then ScatterAdd the work vector to zz */
3697:         PetscCall(VecSeq_CUDA::Set(zz, 0));
3698:       }

3700:       /* ScatterAdd the result from work vector into the full vector when A is compressed */
3701:       if (compressed) {
3702:         PetscCall(PetscLogGpuTimeBegin());
3703:         PetscInt n = (PetscInt)matstruct->cprowIndices->size();
3704:         ScatterAdd<<<(int)((n + 255) / 256), 256, 0, PetscDefaultCudaStream>>>(n, matstruct->cprowIndices->data().get(), cusparsestruct->workVector->data().get(), zarray);
3705:         PetscCall(PetscLogGpuTimeEnd());
3706:       }
3707:     } else {
3708:       if (yy && yy != zz) PetscCall(VecSeq_CUDA::AXPY(zz, 1.0, yy)); /* zz += yy */
3709:     }
3710:     PetscCall(VecCUDARestoreArrayRead(xx, (const PetscScalar **)&xarray));
3711:     if (yy == zz) PetscCall(VecCUDARestoreArray(zz, &zarray));
3712:     else PetscCall(VecCUDARestoreArrayWrite(zz, &zarray));
3713:   } catch (char *ex) {
3714:     SETERRQ(PETSC_COMM_SELF, PETSC_ERR_LIB, "CUSPARSE error: %s", ex);
3715:   }
3716:   if (yy) {
3717:     PetscCall(PetscLogGpuFlops(2.0 * a->nz));
3718:   } else {
3719:     PetscCall(PetscLogGpuFlops(2.0 * a->nz - a->nonzerorowcnt));
3720:   }
3721:   PetscFunctionReturn(PETSC_SUCCESS);
3722: }

3724: static PetscErrorCode MatMultTransposeAdd_SeqAIJCUSPARSE(Mat A, Vec xx, Vec yy, Vec zz)
3725: {
3726:   PetscFunctionBegin;
3727:   PetscCall(MatMultAddKernel_SeqAIJCUSPARSE(A, xx, yy, zz, PETSC_TRUE, PETSC_FALSE));
3728:   PetscFunctionReturn(PETSC_SUCCESS);
3729: }

3731: PETSC_INTERN PetscErrorCode MatGetDiagonal_SeqAIJ(Mat A, Vec xx);

3733: __global__ static void GetDiagonal_CSR(const int *row, const int *col, const PetscScalar *val, const PetscInt len, PetscScalar *diag)
3734: {
3735:   const size_t x = blockIdx.x * blockDim.x + threadIdx.x;

3737:   if (x < len) {
3738:     const PetscInt rowx = row[x], num_non0_row = row[x + 1] - rowx;
3739:     PetscScalar    d = 0.0;

3741:     for (PetscInt i = 0; i < num_non0_row; i++) {
3742:       if (col[i + rowx] == x) {
3743:         d = val[i + rowx];
3744:         break;
3745:       }
3746:     }
3747:     diag[x] = d;
3748:   }
3749: }

3751: static PetscErrorCode MatGetDiagonal_SeqAIJCUSPARSE(Mat A, Vec diag)
3752: {
3753:   Mat_SeqAIJCUSPARSE           *cusparsestruct = (Mat_SeqAIJCUSPARSE *)A->spptr;
3754:   Mat_SeqAIJCUSPARSEMultStruct *matstruct      = (Mat_SeqAIJCUSPARSEMultStruct *)cusparsestruct->mat;
3755:   PetscScalar                  *darray;

3757:   PetscFunctionBegin;
3758:   if (A->offloadmask == PETSC_OFFLOAD_BOTH || A->offloadmask == PETSC_OFFLOAD_GPU) {
3759:     PetscInt   n   = A->rmap->n;
3760:     CsrMatrix *mat = (CsrMatrix *)matstruct->mat;

3762:     PetscCheck(cusparsestruct->format == MAT_CUSPARSE_CSR, PETSC_COMM_SELF, PETSC_ERR_SUP, "Only CSR format supported");
3763:     if (n > 0) {
3764:       PetscCall(VecCUDAGetArrayWrite(diag, &darray));
3765:       GetDiagonal_CSR<<<(int)((n + 255) / 256), 256, 0, PetscDefaultCudaStream>>>(mat->row_offsets->data().get(), mat->column_indices->data().get(), mat->values->data().get(), n, darray);
3766:       PetscCallCUDA(cudaPeekAtLastError());
3767:       PetscCall(VecCUDARestoreArrayWrite(diag, &darray));
3768:     }
3769:   } else PetscCall(MatGetDiagonal_SeqAIJ(A, diag));
3770:   PetscFunctionReturn(PETSC_SUCCESS);
3771: }

3773: static PetscErrorCode MatAssemblyEnd_SeqAIJCUSPARSE(Mat A, MatAssemblyType mode)
3774: {
3775:   PetscFunctionBegin;
3776:   PetscCall(MatAssemblyEnd_SeqAIJ(A, mode));
3777:   PetscFunctionReturn(PETSC_SUCCESS);
3778: }

3780: /*@
3781:   MatCreateSeqAIJCUSPARSE - Creates a sparse matrix in `MATAIJCUSPARSE` (compressed row) format for use on NVIDIA GPUs

3783:   Collective

3785:   Input Parameters:
3786: + comm - MPI communicator, set to `PETSC_COMM_SELF`
3787: . m    - number of rows
3788: . n    - number of columns
3789: . nz   - number of nonzeros per row (same for all rows), ignored if `nnz` is provide
3790: - nnz  - array containing the number of nonzeros in the various rows (possibly different for each row) or `NULL`

3792:   Output Parameter:
3793: . A - the matrix

3795:   Level: intermediate

3797:   Notes:
3798:   This matrix will ultimately pushed down to NVIDIA GPUs and use the CuSPARSE library for
3799:   calculations. For good matrix assembly performance the user should preallocate the matrix
3800:   storage by setting the parameter `nz` (or the array `nnz`).

3802:   It is recommended that one use the `MatCreate()`, `MatSetType()` and/or `MatSetFromOptions()`,
3803:   MatXXXXSetPreallocation() paradgm instead of this routine directly.
3804:   [MatXXXXSetPreallocation() is, for example, `MatSeqAIJSetPreallocation()`]

3806:   The AIJ format, also called
3807:   compressed row storage, is fully compatible with standard Fortran
3808:   storage.  That is, the stored row and column indices can begin at
3809:   either one (as in Fortran) or zero.

3811:   Specify the preallocated storage with either nz or nnz (not both).
3812:   Set `nz` = `PETSC_DEFAULT` and `nnz` = `NULL` for PETSc to control dynamic memory
3813:   allocation.

3815:   When working with matrices for GPUs, it is often better to use the `MatSetPreallocationCOO()` and `MatSetValuesCOO()` paradigm rather than using this routine and `MatSetValues()`

3817: .seealso: [](ch_matrices), `Mat`, `MATSEQAIJCUSPARSE`, `MatCreate()`, `MatCreateAIJ()`, `MatSetValues()`, `MatSeqAIJSetColumnIndices()`, `MatCreateSeqAIJWithArrays()`, `MATAIJCUSPARSE`,
3818:           `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
3819: @*/
3820: PetscErrorCode MatCreateSeqAIJCUSPARSE(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt nz, const PetscInt nnz[], Mat *A)
3821: {
3822:   PetscFunctionBegin;
3823:   PetscCall(MatCreate(comm, A));
3824:   PetscCall(MatSetSizes(*A, m, n, m, n));
3825:   PetscCall(MatSetType(*A, MATSEQAIJCUSPARSE));
3826:   PetscCall(MatSeqAIJSetPreallocation_SeqAIJ(*A, nz, (PetscInt *)nnz));
3827:   PetscFunctionReturn(PETSC_SUCCESS);
3828: }

3830: static PetscErrorCode MatDestroy_SeqAIJCUSPARSE(Mat A)
3831: {
3832:   PetscFunctionBegin;
3833:   if (A->factortype == MAT_FACTOR_NONE) {
3834:     PetscCall(MatSeqAIJCUSPARSE_Destroy(A));
3835:   } else {
3836:     PetscCall(MatSeqAIJCUSPARSETriFactors_Destroy((Mat_SeqAIJCUSPARSETriFactors **)&A->spptr));
3837:   }
3838:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatSeqAIJCopySubArray_C", NULL));
3839:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatCUSPARSESetFormat_C", NULL));
3840:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatCUSPARSESetUseCPUSolve_C", NULL));
3841:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatProductSetFromOptions_seqaijcusparse_seqdensecuda_C", NULL));
3842:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatProductSetFromOptions_seqaijcusparse_seqdense_C", NULL));
3843:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatProductSetFromOptions_seqaijcusparse_seqaijcusparse_C", NULL));
3844:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatFactorGetSolverType_C", NULL));
3845:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatSetPreallocationCOO_C", NULL));
3846:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatSetValuesCOO_C", NULL));
3847:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatConvert_seqaijcusparse_hypre_C", NULL));
3848:   PetscCall(MatDestroy_SeqAIJ(A));
3849:   PetscFunctionReturn(PETSC_SUCCESS);
3850: }

3852: PETSC_INTERN PetscErrorCode MatConvert_SeqAIJ_SeqAIJCUSPARSE(Mat, MatType, MatReuse, Mat *);
3853: static PetscErrorCode       MatBindToCPU_SeqAIJCUSPARSE(Mat, PetscBool);
3854: static PetscErrorCode       MatDuplicate_SeqAIJCUSPARSE(Mat A, MatDuplicateOption cpvalues, Mat *B)
3855: {
3856:   PetscFunctionBegin;
3857:   PetscCall(MatDuplicate_SeqAIJ(A, cpvalues, B));
3858:   PetscCall(MatConvert_SeqAIJ_SeqAIJCUSPARSE(*B, MATSEQAIJCUSPARSE, MAT_INPLACE_MATRIX, B));
3859:   PetscFunctionReturn(PETSC_SUCCESS);
3860: }

3862: static PetscErrorCode MatAXPY_SeqAIJCUSPARSE(Mat Y, PetscScalar a, Mat X, MatStructure str)
3863: {
3864:   Mat_SeqAIJ         *x = (Mat_SeqAIJ *)X->data, *y = (Mat_SeqAIJ *)Y->data;
3865:   Mat_SeqAIJCUSPARSE *cy;
3866:   Mat_SeqAIJCUSPARSE *cx;
3867:   PetscScalar        *ay;
3868:   const PetscScalar  *ax;
3869:   CsrMatrix          *csry, *csrx;

3871:   PetscFunctionBegin;
3872:   cy = (Mat_SeqAIJCUSPARSE *)Y->spptr;
3873:   cx = (Mat_SeqAIJCUSPARSE *)X->spptr;
3874:   if (X->ops->axpy != Y->ops->axpy) {
3875:     PetscCall(MatSeqAIJCUSPARSEInvalidateTranspose(Y, PETSC_FALSE));
3876:     PetscCall(MatAXPY_SeqAIJ(Y, a, X, str));
3877:     PetscFunctionReturn(PETSC_SUCCESS);
3878:   }
3879:   /* if we are here, it means both matrices are bound to GPU */
3880:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(Y));
3881:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(X));
3882:   PetscCheck(cy->format == MAT_CUSPARSE_CSR, PetscObjectComm((PetscObject)Y), PETSC_ERR_GPU, "only MAT_CUSPARSE_CSR supported");
3883:   PetscCheck(cx->format == MAT_CUSPARSE_CSR, PetscObjectComm((PetscObject)X), PETSC_ERR_GPU, "only MAT_CUSPARSE_CSR supported");
3884:   csry = (CsrMatrix *)cy->mat->mat;
3885:   csrx = (CsrMatrix *)cx->mat->mat;
3886:   /* see if we can turn this into a cublas axpy */
3887:   if (str != SAME_NONZERO_PATTERN && x->nz == y->nz && !x->compressedrow.use && !y->compressedrow.use) {
3888:     bool eq = thrust::equal(thrust::device, csry->row_offsets->begin(), csry->row_offsets->end(), csrx->row_offsets->begin());
3889:     if (eq) eq = thrust::equal(thrust::device, csry->column_indices->begin(), csry->column_indices->end(), csrx->column_indices->begin());
3890:     if (eq) str = SAME_NONZERO_PATTERN;
3891:   }
3892:   /* spgeam is buggy with one column */
3893:   if (Y->cmap->n == 1 && str != SAME_NONZERO_PATTERN) str = DIFFERENT_NONZERO_PATTERN;

3895:   if (str == SUBSET_NONZERO_PATTERN) {
3896:     PetscScalar b = 1.0;
3897: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
3898:     size_t bufferSize;
3899:     void  *buffer;
3900: #endif

3902:     PetscCall(MatSeqAIJCUSPARSEGetArrayRead(X, &ax));
3903:     PetscCall(MatSeqAIJCUSPARSEGetArray(Y, &ay));
3904:     PetscCallCUSPARSE(cusparseSetPointerMode(cy->handle, CUSPARSE_POINTER_MODE_HOST));
3905: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
3906:     PetscCallCUSPARSE(cusparse_csr_spgeam_bufferSize(cy->handle, Y->rmap->n, Y->cmap->n, &a, cx->mat->descr, x->nz, ax, csrx->row_offsets->data().get(), csrx->column_indices->data().get(), &b, cy->mat->descr, y->nz, ay, csry->row_offsets->data().get(),
3907:                                                      csry->column_indices->data().get(), cy->mat->descr, ay, csry->row_offsets->data().get(), csry->column_indices->data().get(), &bufferSize));
3908:     PetscCallCUDA(cudaMalloc(&buffer, bufferSize));
3909:     PetscCall(PetscLogGpuTimeBegin());
3910:     PetscCallCUSPARSE(cusparse_csr_spgeam(cy->handle, Y->rmap->n, Y->cmap->n, &a, cx->mat->descr, x->nz, ax, csrx->row_offsets->data().get(), csrx->column_indices->data().get(), &b, cy->mat->descr, y->nz, ay, csry->row_offsets->data().get(),
3911:                                           csry->column_indices->data().get(), cy->mat->descr, ay, csry->row_offsets->data().get(), csry->column_indices->data().get(), buffer));
3912:     PetscCall(PetscLogGpuFlops(x->nz + y->nz));
3913:     PetscCall(PetscLogGpuTimeEnd());
3914:     PetscCallCUDA(cudaFree(buffer));
3915: #else
3916:     PetscCall(PetscLogGpuTimeBegin());
3917:     PetscCallCUSPARSE(cusparse_csr_spgeam(cy->handle, Y->rmap->n, Y->cmap->n, &a, cx->mat->descr, x->nz, ax, csrx->row_offsets->data().get(), csrx->column_indices->data().get(), &b, cy->mat->descr, y->nz, ay, csry->row_offsets->data().get(),
3918:                                           csry->column_indices->data().get(), cy->mat->descr, ay, csry->row_offsets->data().get(), csry->column_indices->data().get()));
3919:     PetscCall(PetscLogGpuFlops(x->nz + y->nz));
3920:     PetscCall(PetscLogGpuTimeEnd());
3921: #endif
3922:     PetscCallCUSPARSE(cusparseSetPointerMode(cy->handle, CUSPARSE_POINTER_MODE_DEVICE));
3923:     PetscCall(MatSeqAIJCUSPARSERestoreArrayRead(X, &ax));
3924:     PetscCall(MatSeqAIJCUSPARSERestoreArray(Y, &ay));
3925:   } else if (str == SAME_NONZERO_PATTERN) {
3926:     cublasHandle_t cublasv2handle;
3927:     PetscBLASInt   one = 1, bnz = 1;

3929:     PetscCall(MatSeqAIJCUSPARSEGetArrayRead(X, &ax));
3930:     PetscCall(MatSeqAIJCUSPARSEGetArray(Y, &ay));
3931:     PetscCall(PetscCUBLASGetHandle(&cublasv2handle));
3932:     PetscCall(PetscBLASIntCast(x->nz, &bnz));
3933:     PetscCall(PetscLogGpuTimeBegin());
3934:     PetscCallCUBLAS(cublasXaxpy(cublasv2handle, bnz, &a, ax, one, ay, one));
3935:     PetscCall(PetscLogGpuFlops(2.0 * bnz));
3936:     PetscCall(PetscLogGpuTimeEnd());
3937:     PetscCall(MatSeqAIJCUSPARSERestoreArrayRead(X, &ax));
3938:     PetscCall(MatSeqAIJCUSPARSERestoreArray(Y, &ay));
3939:   } else {
3940:     PetscCall(MatSeqAIJCUSPARSEInvalidateTranspose(Y, PETSC_FALSE));
3941:     PetscCall(MatAXPY_SeqAIJ(Y, a, X, str));
3942:   }
3943:   PetscFunctionReturn(PETSC_SUCCESS);
3944: }

3946: static PetscErrorCode MatScale_SeqAIJCUSPARSE(Mat Y, PetscScalar a)
3947: {
3948:   Mat_SeqAIJ    *y = (Mat_SeqAIJ *)Y->data;
3949:   PetscScalar   *ay;
3950:   cublasHandle_t cublasv2handle;
3951:   PetscBLASInt   one = 1, bnz = 1;

3953:   PetscFunctionBegin;
3954:   PetscCall(MatSeqAIJCUSPARSEGetArray(Y, &ay));
3955:   PetscCall(PetscCUBLASGetHandle(&cublasv2handle));
3956:   PetscCall(PetscBLASIntCast(y->nz, &bnz));
3957:   PetscCall(PetscLogGpuTimeBegin());
3958:   PetscCallCUBLAS(cublasXscal(cublasv2handle, bnz, &a, ay, one));
3959:   PetscCall(PetscLogGpuFlops(bnz));
3960:   PetscCall(PetscLogGpuTimeEnd());
3961:   PetscCall(MatSeqAIJCUSPARSERestoreArray(Y, &ay));
3962:   PetscFunctionReturn(PETSC_SUCCESS);
3963: }

3965: static PetscErrorCode MatZeroEntries_SeqAIJCUSPARSE(Mat A)
3966: {
3967:   PetscBool   gpu = PETSC_FALSE;
3968:   Mat_SeqAIJ *a   = (Mat_SeqAIJ *)A->data;

3970:   PetscFunctionBegin;
3971:   if (A->factortype == MAT_FACTOR_NONE) {
3972:     Mat_SeqAIJCUSPARSE *spptr = (Mat_SeqAIJCUSPARSE *)A->spptr;
3973:     if (spptr->mat) {
3974:       CsrMatrix *matrix = (CsrMatrix *)spptr->mat->mat;
3975:       if (matrix->values) {
3976:         gpu = PETSC_TRUE;
3977:         thrust::fill(thrust::device, matrix->values->begin(), matrix->values->end(), 0.);
3978:       }
3979:     }
3980:     if (spptr->matTranspose) {
3981:       CsrMatrix *matrix = (CsrMatrix *)spptr->matTranspose->mat;
3982:       if (matrix->values) thrust::fill(thrust::device, matrix->values->begin(), matrix->values->end(), 0.);
3983:     }
3984:   }
3985:   if (gpu) A->offloadmask = PETSC_OFFLOAD_GPU;
3986:   else {
3987:     PetscCall(PetscArrayzero(a->a, a->i[A->rmap->n]));
3988:     A->offloadmask = PETSC_OFFLOAD_CPU;
3989:   }
3990:   PetscFunctionReturn(PETSC_SUCCESS);
3991: }

3993: static PetscErrorCode MatGetCurrentMemType_SeqAIJCUSPARSE(PETSC_UNUSED Mat A, PetscMemType *m)
3994: {
3995:   PetscFunctionBegin;
3996:   *m = PETSC_MEMTYPE_CUDA;
3997:   PetscFunctionReturn(PETSC_SUCCESS);
3998: }

4000: static PetscErrorCode MatBindToCPU_SeqAIJCUSPARSE(Mat A, PetscBool flg)
4001: {
4002:   Mat_SeqAIJ *a = (Mat_SeqAIJ *)A->data;

4004:   PetscFunctionBegin;
4005:   if (A->factortype != MAT_FACTOR_NONE) {
4006:     A->boundtocpu = flg;
4007:     PetscFunctionReturn(PETSC_SUCCESS);
4008:   }
4009:   if (flg) {
4010:     PetscCall(MatSeqAIJCUSPARSECopyFromGPU(A));

4012:     A->ops->scale                     = MatScale_SeqAIJ;
4013:     A->ops->getdiagonal               = MatGetDiagonal_SeqAIJ;
4014:     A->ops->axpy                      = MatAXPY_SeqAIJ;
4015:     A->ops->zeroentries               = MatZeroEntries_SeqAIJ;
4016:     A->ops->mult                      = MatMult_SeqAIJ;
4017:     A->ops->multadd                   = MatMultAdd_SeqAIJ;
4018:     A->ops->multtranspose             = MatMultTranspose_SeqAIJ;
4019:     A->ops->multtransposeadd          = MatMultTransposeAdd_SeqAIJ;
4020:     A->ops->multhermitiantranspose    = NULL;
4021:     A->ops->multhermitiantransposeadd = NULL;
4022:     A->ops->productsetfromoptions     = MatProductSetFromOptions_SeqAIJ;
4023:     A->ops->getcurrentmemtype         = NULL;
4024:     PetscCall(PetscMemzero(a->ops, sizeof(Mat_SeqAIJOps)));
4025:     PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatSeqAIJCopySubArray_C", NULL));
4026:     PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatProductSetFromOptions_seqaijcusparse_seqdensecuda_C", NULL));
4027:     PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatProductSetFromOptions_seqaijcusparse_seqdense_C", NULL));
4028:     PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatSetPreallocationCOO_C", NULL));
4029:     PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatSetValuesCOO_C", NULL));
4030:     PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatProductSetFromOptions_seqaijcusparse_seqaijcusparse_C", NULL));
4031:   } else {
4032:     A->ops->scale                     = MatScale_SeqAIJCUSPARSE;
4033:     A->ops->getdiagonal               = MatGetDiagonal_SeqAIJCUSPARSE;
4034:     A->ops->axpy                      = MatAXPY_SeqAIJCUSPARSE;
4035:     A->ops->zeroentries               = MatZeroEntries_SeqAIJCUSPARSE;
4036:     A->ops->mult                      = MatMult_SeqAIJCUSPARSE;
4037:     A->ops->multadd                   = MatMultAdd_SeqAIJCUSPARSE;
4038:     A->ops->multtranspose             = MatMultTranspose_SeqAIJCUSPARSE;
4039:     A->ops->multtransposeadd          = MatMultTransposeAdd_SeqAIJCUSPARSE;
4040:     A->ops->multhermitiantranspose    = MatMultHermitianTranspose_SeqAIJCUSPARSE;
4041:     A->ops->multhermitiantransposeadd = MatMultHermitianTransposeAdd_SeqAIJCUSPARSE;
4042:     A->ops->productsetfromoptions     = MatProductSetFromOptions_SeqAIJCUSPARSE;
4043:     A->ops->getcurrentmemtype         = MatGetCurrentMemType_SeqAIJCUSPARSE;
4044:     a->ops->getarray                  = MatSeqAIJGetArray_SeqAIJCUSPARSE;
4045:     a->ops->restorearray              = MatSeqAIJRestoreArray_SeqAIJCUSPARSE;
4046:     a->ops->getarrayread              = MatSeqAIJGetArrayRead_SeqAIJCUSPARSE;
4047:     a->ops->restorearrayread          = MatSeqAIJRestoreArrayRead_SeqAIJCUSPARSE;
4048:     a->ops->getarraywrite             = MatSeqAIJGetArrayWrite_SeqAIJCUSPARSE;
4049:     a->ops->restorearraywrite         = MatSeqAIJRestoreArrayWrite_SeqAIJCUSPARSE;
4050:     a->ops->getcsrandmemtype          = MatSeqAIJGetCSRAndMemType_SeqAIJCUSPARSE;

4052:     PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatSeqAIJCopySubArray_C", MatSeqAIJCopySubArray_SeqAIJCUSPARSE));
4053:     PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatProductSetFromOptions_seqaijcusparse_seqdensecuda_C", MatProductSetFromOptions_SeqAIJCUSPARSE));
4054:     PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatProductSetFromOptions_seqaijcusparse_seqdense_C", MatProductSetFromOptions_SeqAIJCUSPARSE));
4055:     PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatSetPreallocationCOO_C", MatSetPreallocationCOO_SeqAIJCUSPARSE));
4056:     PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatSetValuesCOO_C", MatSetValuesCOO_SeqAIJCUSPARSE));
4057:     PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatProductSetFromOptions_seqaijcusparse_seqaijcusparse_C", MatProductSetFromOptions_SeqAIJCUSPARSE));
4058:   }
4059:   A->boundtocpu = flg;
4060:   if (flg && a->inode.size_csr) {
4061:     a->inode.use = PETSC_TRUE;
4062:   } else {
4063:     a->inode.use = PETSC_FALSE;
4064:   }
4065:   PetscFunctionReturn(PETSC_SUCCESS);
4066: }

4068: PETSC_INTERN PetscErrorCode MatConvert_SeqAIJ_SeqAIJCUSPARSE(Mat A, MatType, MatReuse reuse, Mat *newmat)
4069: {
4070:   Mat B;

4072:   PetscFunctionBegin;
4073:   PetscCall(PetscDeviceInitialize(PETSC_DEVICE_CUDA)); /* first use of CUSPARSE may be via MatConvert */
4074:   if (reuse == MAT_INITIAL_MATRIX) {
4075:     PetscCall(MatDuplicate(A, MAT_COPY_VALUES, newmat));
4076:   } else if (reuse == MAT_REUSE_MATRIX) {
4077:     PetscCall(MatCopy(A, *newmat, SAME_NONZERO_PATTERN));
4078:   }
4079:   B = *newmat;

4081:   PetscCall(PetscFree(B->defaultvectype));
4082:   PetscCall(PetscStrallocpy(VECCUDA, &B->defaultvectype));

4084:   if (reuse != MAT_REUSE_MATRIX && !B->spptr) {
4085:     if (B->factortype == MAT_FACTOR_NONE) {
4086:       Mat_SeqAIJCUSPARSE *spptr;
4087:       PetscCall(PetscNew(&spptr));
4088:       PetscCallCUSPARSE(cusparseCreate(&spptr->handle));
4089:       PetscCallCUSPARSE(cusparseSetStream(spptr->handle, PetscDefaultCudaStream));
4090:       spptr->format = MAT_CUSPARSE_CSR;
4091: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
4092:   #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
4093:       spptr->spmvAlg = CUSPARSE_SPMV_CSR_ALG1; /* default, since we only support csr */
4094:   #else
4095:       spptr->spmvAlg = CUSPARSE_CSRMV_ALG1; /* default, since we only support csr */
4096:   #endif
4097:       spptr->spmmAlg    = CUSPARSE_SPMM_CSR_ALG1; /* default, only support column-major dense matrix B */
4098:       spptr->csr2cscAlg = CUSPARSE_CSR2CSC_ALG1;
4099: #endif
4100:       B->spptr = spptr;
4101:     } else {
4102:       Mat_SeqAIJCUSPARSETriFactors *spptr;

4104:       PetscCall(PetscNew(&spptr));
4105:       PetscCallCUSPARSE(cusparseCreate(&spptr->handle));
4106:       PetscCallCUSPARSE(cusparseSetStream(spptr->handle, PetscDefaultCudaStream));
4107:       B->spptr = spptr;
4108:     }
4109:     B->offloadmask = PETSC_OFFLOAD_UNALLOCATED;
4110:   }
4111:   B->ops->assemblyend       = MatAssemblyEnd_SeqAIJCUSPARSE;
4112:   B->ops->destroy           = MatDestroy_SeqAIJCUSPARSE;
4113:   B->ops->setoption         = MatSetOption_SeqAIJCUSPARSE;
4114:   B->ops->setfromoptions    = MatSetFromOptions_SeqAIJCUSPARSE;
4115:   B->ops->bindtocpu         = MatBindToCPU_SeqAIJCUSPARSE;
4116:   B->ops->duplicate         = MatDuplicate_SeqAIJCUSPARSE;
4117:   B->ops->getcurrentmemtype = MatGetCurrentMemType_SeqAIJCUSPARSE;

4119:   PetscCall(MatBindToCPU_SeqAIJCUSPARSE(B, PETSC_FALSE));
4120:   PetscCall(PetscObjectChangeTypeName((PetscObject)B, MATSEQAIJCUSPARSE));
4121:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatCUSPARSESetFormat_C", MatCUSPARSESetFormat_SeqAIJCUSPARSE));
4122: #if defined(PETSC_HAVE_HYPRE)
4123:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_seqaijcusparse_hypre_C", MatConvert_AIJ_HYPRE));
4124: #endif
4125:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatCUSPARSESetUseCPUSolve_C", MatCUSPARSESetUseCPUSolve_SeqAIJCUSPARSE));
4126:   PetscFunctionReturn(PETSC_SUCCESS);
4127: }

4129: PETSC_EXTERN PetscErrorCode MatCreate_SeqAIJCUSPARSE(Mat B)
4130: {
4131:   PetscFunctionBegin;
4132:   PetscCall(MatCreate_SeqAIJ(B));
4133:   PetscCall(MatConvert_SeqAIJ_SeqAIJCUSPARSE(B, MATSEQAIJCUSPARSE, MAT_INPLACE_MATRIX, &B));
4134:   PetscFunctionReturn(PETSC_SUCCESS);
4135: }

4137: /*MC
4138:    MATSEQAIJCUSPARSE - MATAIJCUSPARSE = "(seq)aijcusparse" - A matrix type to be used for sparse matrices on NVIDIA GPUs.

4140:    Options Database Keys:
4141: +  -mat_type aijcusparse                 - Sets the matrix type to "seqaijcusparse" during a call to `MatSetFromOptions()`
4142: .  -mat_cusparse_storage_format csr      - Sets the storage format of matrices (for `MatMult()` and factors in `MatSolve()`).
4143:                                            Other options include ell (ellpack) or hyb (hybrid).
4144: .  -mat_cusparse_mult_storage_format csr - Sets the storage format of matrices (for `MatMult()`). Other options include ell (ellpack) or hyb (hybrid).
4145: -  -mat_cusparse_use_cpu_solve           - Performs the `MatSolve()` on the CPU

4147:   Level: beginner

4149:   Notes:
4150:   These matrices can be in either CSR, ELL, or HYB format.

4152:   All matrix calculations are performed on NVIDIA GPUs using the cuSPARSE library.

4154:   Uses 32-bit integers internally. If PETSc is configured `--with-64-bit-indices`, the integer row and column indices are stored on the GPU with `int`. It is unclear what happens
4155:   if some integer values passed in do not fit in `int`.

4157: .seealso: [](ch_matrices), `Mat`, `MatCreateSeqAIJCUSPARSE()`, `MatCUSPARSESetUseCPUSolve()`, `MATAIJCUSPARSE`, `MatCreateAIJCUSPARSE()`, `MatCUSPARSESetFormat()`, `MatCUSPARSEStorageFormat`, `MatCUSPARSEFormatOperation`
4158: M*/

4160: PETSC_INTERN PetscErrorCode MatSolverTypeRegister_CUSPARSE(void)
4161: {
4162:   PetscFunctionBegin;
4163:   PetscCall(MatSolverTypeRegister(MATSOLVERCUSPARSE, MATSEQAIJCUSPARSE, MAT_FACTOR_LU, MatGetFactor_seqaijcusparse_cusparse));
4164:   PetscCall(MatSolverTypeRegister(MATSOLVERCUSPARSE, MATSEQAIJCUSPARSE, MAT_FACTOR_CHOLESKY, MatGetFactor_seqaijcusparse_cusparse));
4165:   PetscCall(MatSolverTypeRegister(MATSOLVERCUSPARSE, MATSEQAIJCUSPARSE, MAT_FACTOR_ILU, MatGetFactor_seqaijcusparse_cusparse));
4166:   PetscCall(MatSolverTypeRegister(MATSOLVERCUSPARSE, MATSEQAIJCUSPARSE, MAT_FACTOR_ICC, MatGetFactor_seqaijcusparse_cusparse));
4167:   PetscFunctionReturn(PETSC_SUCCESS);
4168: }

4170: static PetscErrorCode MatSeqAIJCUSPARSE_Destroy(Mat mat)
4171: {
4172:   Mat_SeqAIJCUSPARSE *cusp = static_cast<Mat_SeqAIJCUSPARSE *>(mat->spptr);

4174:   PetscFunctionBegin;
4175:   if (cusp) {
4176:     PetscCall(MatSeqAIJCUSPARSEMultStruct_Destroy(&cusp->mat, cusp->format));
4177:     PetscCall(MatSeqAIJCUSPARSEMultStruct_Destroy(&cusp->matTranspose, cusp->format));
4178:     delete cusp->workVector;
4179:     delete cusp->rowoffsets_gpu;
4180:     delete cusp->csr2csc_i;
4181:     delete cusp->coords;
4182:     if (cusp->handle) PetscCallCUSPARSE(cusparseDestroy(cusp->handle));
4183:     PetscCall(PetscFree(mat->spptr));
4184:   }
4185:   PetscFunctionReturn(PETSC_SUCCESS);
4186: }

4188: static PetscErrorCode CsrMatrix_Destroy(CsrMatrix **mat)
4189: {
4190:   PetscFunctionBegin;
4191:   if (*mat) {
4192:     delete (*mat)->values;
4193:     delete (*mat)->column_indices;
4194:     delete (*mat)->row_offsets;
4195:     delete *mat;
4196:     *mat = 0;
4197:   }
4198:   PetscFunctionReturn(PETSC_SUCCESS);
4199: }

4201: #if PETSC_PKG_CUDA_VERSION_LT(11, 4, 0)
4202: static PetscErrorCode MatSeqAIJCUSPARSEMultStruct_Destroy(Mat_SeqAIJCUSPARSETriFactorStruct **trifactor)
4203: {
4204:   PetscFunctionBegin;
4205:   if (*trifactor) {
4206:     if ((*trifactor)->descr) PetscCallCUSPARSE(cusparseDestroyMatDescr((*trifactor)->descr));
4207:     if ((*trifactor)->solveInfo) PetscCallCUSPARSE(cusparseDestroyCsrsvInfo((*trifactor)->solveInfo));
4208:     PetscCall(CsrMatrix_Destroy(&(*trifactor)->csrMat));
4209:     if ((*trifactor)->solveBuffer) PetscCallCUDA(cudaFree((*trifactor)->solveBuffer));
4210:     if ((*trifactor)->AA_h) PetscCallCUDA(cudaFreeHost((*trifactor)->AA_h));
4211:   #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
4212:     if ((*trifactor)->csr2cscBuffer) PetscCallCUDA(cudaFree((*trifactor)->csr2cscBuffer));
4213:   #endif
4214:     PetscCall(PetscFree(*trifactor));
4215:   }
4216:   PetscFunctionReturn(PETSC_SUCCESS);
4217: }
4218: #endif

4220: static PetscErrorCode MatSeqAIJCUSPARSEMultStruct_Destroy(Mat_SeqAIJCUSPARSEMultStruct **matstruct, MatCUSPARSEStorageFormat format)
4221: {
4222:   CsrMatrix *mat;

4224:   PetscFunctionBegin;
4225:   if (*matstruct) {
4226:     if ((*matstruct)->mat) {
4227:       if (format == MAT_CUSPARSE_ELL || format == MAT_CUSPARSE_HYB) {
4228: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
4229:         SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "MAT_CUSPARSE_ELL and MAT_CUSPARSE_HYB are not supported since CUDA-11.0");
4230: #else
4231:         cusparseHybMat_t hybMat = (cusparseHybMat_t)(*matstruct)->mat;
4232:         PetscCallCUSPARSE(cusparseDestroyHybMat(hybMat));
4233: #endif
4234:       } else {
4235:         mat = (CsrMatrix *)(*matstruct)->mat;
4236:         PetscCall(CsrMatrix_Destroy(&mat));
4237:       }
4238:     }
4239:     if ((*matstruct)->descr) PetscCallCUSPARSE(cusparseDestroyMatDescr((*matstruct)->descr));
4240:     delete (*matstruct)->cprowIndices;
4241:     if ((*matstruct)->alpha_one) PetscCallCUDA(cudaFree((*matstruct)->alpha_one));
4242:     if ((*matstruct)->beta_zero) PetscCallCUDA(cudaFree((*matstruct)->beta_zero));
4243:     if ((*matstruct)->beta_one) PetscCallCUDA(cudaFree((*matstruct)->beta_one));

4245: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
4246:     Mat_SeqAIJCUSPARSEMultStruct *mdata = *matstruct;
4247:     if (mdata->matDescr) PetscCallCUSPARSE(cusparseDestroySpMat(mdata->matDescr));

4249:     for (int i = 0; i < 3; i++) {
4250:       if (mdata->cuSpMV[i].initialized) {
4251:         PetscCallCUDA(cudaFree(mdata->cuSpMV[i].spmvBuffer));
4252:         PetscCallCUSPARSE(cusparseDestroyDnVec(mdata->cuSpMV[i].vecXDescr));
4253:         PetscCallCUSPARSE(cusparseDestroyDnVec(mdata->cuSpMV[i].vecYDescr));
4254:   #if PETSC_PKG_CUDA_VERSION_GE(12, 4, 0)
4255:         if (mdata->matDescr_SpMV[i]) PetscCallCUSPARSE(cusparseDestroySpMat(mdata->matDescr_SpMV[i]));
4256:         if (mdata->matDescr_SpMM[i]) PetscCallCUSPARSE(cusparseDestroySpMat(mdata->matDescr_SpMM[i]));
4257:   #endif
4258:       }
4259:     }
4260: #endif
4261:     delete *matstruct;
4262:     *matstruct = NULL;
4263:   }
4264:   PetscFunctionReturn(PETSC_SUCCESS);
4265: }

4267: PetscErrorCode MatSeqAIJCUSPARSETriFactors_Reset(Mat_SeqAIJCUSPARSETriFactors_p *trifactors)
4268: {
4269:   Mat_SeqAIJCUSPARSETriFactors *fs = *trifactors;

4271:   PetscFunctionBegin;
4272:   if (fs) {
4273: #if PETSC_PKG_CUDA_VERSION_LT(11, 4, 0)
4274:     PetscCall(MatSeqAIJCUSPARSEMultStruct_Destroy(&fs->loTriFactorPtr));
4275:     PetscCall(MatSeqAIJCUSPARSEMultStruct_Destroy(&fs->upTriFactorPtr));
4276:     PetscCall(MatSeqAIJCUSPARSEMultStruct_Destroy(&fs->loTriFactorPtrTranspose));
4277:     PetscCall(MatSeqAIJCUSPARSEMultStruct_Destroy(&fs->upTriFactorPtrTranspose));
4278:     delete fs->workVector;
4279:     fs->workVector = NULL;
4280: #endif
4281:     delete fs->rpermIndices;
4282:     delete fs->cpermIndices;
4283:     fs->rpermIndices  = NULL;
4284:     fs->cpermIndices  = NULL;
4285:     fs->init_dev_prop = PETSC_FALSE;
4286: #if PETSC_PKG_CUDA_VERSION_GE(11, 4, 0)
4287:     PetscCallCUDA(cudaFree(fs->csrRowPtr));
4288:     PetscCallCUDA(cudaFree(fs->csrColIdx));
4289:     PetscCallCUDA(cudaFree(fs->csrRowPtr32));
4290:     PetscCallCUDA(cudaFree(fs->csrColIdx32));
4291:     PetscCallCUDA(cudaFree(fs->csrVal));
4292:     PetscCallCUDA(cudaFree(fs->diag));
4293:     PetscCallCUDA(cudaFree(fs->X));
4294:     PetscCallCUDA(cudaFree(fs->Y));
4295:     // PetscCallCUDA(cudaFree(fs->factBuffer_M)); /* No needed since factBuffer_M shares with one of spsvBuffer_L/U */
4296:     PetscCallCUDA(cudaFree(fs->spsvBuffer_L));
4297:     PetscCallCUDA(cudaFree(fs->spsvBuffer_U));
4298:     PetscCallCUDA(cudaFree(fs->spsvBuffer_Lt));
4299:     PetscCallCUDA(cudaFree(fs->spsvBuffer_Ut));
4300:     PetscCallCUSPARSE(cusparseDestroyMatDescr(fs->matDescr_M));
4301:     PetscCallCUSPARSE(cusparseDestroySpMat(fs->spMatDescr_L));
4302:     PetscCallCUSPARSE(cusparseDestroySpMat(fs->spMatDescr_U));
4303:     PetscCallCUSPARSE(cusparseSpSV_destroyDescr(fs->spsvDescr_L));
4304:     PetscCallCUSPARSE(cusparseSpSV_destroyDescr(fs->spsvDescr_Lt));
4305:     PetscCallCUSPARSE(cusparseSpSV_destroyDescr(fs->spsvDescr_U));
4306:     PetscCallCUSPARSE(cusparseSpSV_destroyDescr(fs->spsvDescr_Ut));
4307:     PetscCallCUSPARSE(cusparseDestroyDnVec(fs->dnVecDescr_X));
4308:     PetscCallCUSPARSE(cusparseDestroyDnVec(fs->dnVecDescr_Y));
4309:     PetscCallCUSPARSE(cusparseDestroyCsrilu02Info(fs->ilu0Info_M));
4310:     PetscCallCUSPARSE(cusparseDestroyCsric02Info(fs->ic0Info_M));
4311:     PetscCall(PetscFree(fs->csrRowPtr_h));
4312:     PetscCall(PetscFree(fs->csrVal_h));
4313:     PetscCall(PetscFree(fs->diag_h));
4314:     fs->createdTransposeSpSVDescr    = PETSC_FALSE;
4315:     fs->updatedTransposeSpSVAnalysis = PETSC_FALSE;
4316: #endif
4317:   }
4318:   PetscFunctionReturn(PETSC_SUCCESS);
4319: }

4321: static PetscErrorCode MatSeqAIJCUSPARSETriFactors_Destroy(Mat_SeqAIJCUSPARSETriFactors **trifactors)
4322: {
4323:   PetscFunctionBegin;
4324:   if (*trifactors) {
4325:     PetscCall(MatSeqAIJCUSPARSETriFactors_Reset(trifactors));
4326:     PetscCallCUSPARSE(cusparseDestroy((*trifactors)->handle));
4327:     PetscCall(PetscFree(*trifactors));
4328:   }
4329:   PetscFunctionReturn(PETSC_SUCCESS);
4330: }

4332: struct IJCompare {
4333:   __host__ __device__ inline bool operator()(const thrust::tuple<PetscInt, PetscInt> &t1, const thrust::tuple<PetscInt, PetscInt> &t2)
4334:   {
4335:     if (thrust::get<0>(t1) < thrust::get<0>(t2)) return true;
4336:     if (thrust::get<0>(t1) == thrust::get<0>(t2)) return thrust::get<1>(t1) < thrust::get<1>(t2);
4337:     return false;
4338:   }
4339: };

4341: static PetscErrorCode MatSeqAIJCUSPARSEInvalidateTranspose(Mat A, PetscBool destroy)
4342: {
4343:   Mat_SeqAIJCUSPARSE *cusp = (Mat_SeqAIJCUSPARSE *)A->spptr;

4345:   PetscFunctionBegin;
4346:   PetscCheckTypeName(A, MATSEQAIJCUSPARSE);
4347:   if (!cusp) PetscFunctionReturn(PETSC_SUCCESS);
4348:   if (destroy) {
4349:     PetscCall(MatSeqAIJCUSPARSEMultStruct_Destroy(&cusp->matTranspose, cusp->format));
4350:     delete cusp->csr2csc_i;
4351:     cusp->csr2csc_i = NULL;
4352:   }
4353:   A->transupdated = PETSC_FALSE;
4354:   PetscFunctionReturn(PETSC_SUCCESS);
4355: }

4357: static PetscErrorCode MatCOOStructDestroy_SeqAIJCUSPARSE(void **data)
4358: {
4359:   MatCOOStruct_SeqAIJ *coo = (MatCOOStruct_SeqAIJ *)*data;

4361:   PetscFunctionBegin;
4362:   PetscCallCUDA(cudaFree(coo->perm));
4363:   PetscCallCUDA(cudaFree(coo->jmap));
4364:   PetscCall(PetscFree(coo));
4365:   PetscFunctionReturn(PETSC_SUCCESS);
4366: }

4368: static PetscErrorCode MatSetPreallocationCOO_SeqAIJCUSPARSE(Mat mat, PetscCount coo_n, PetscInt coo_i[], PetscInt coo_j[])
4369: {
4370:   PetscBool            dev_ij = PETSC_FALSE;
4371:   PetscMemType         mtype  = PETSC_MEMTYPE_HOST;
4372:   PetscInt            *i, *j;
4373:   PetscContainer       container_h;
4374:   MatCOOStruct_SeqAIJ *coo_h, *coo_d;

4376:   PetscFunctionBegin;
4377:   PetscCall(PetscGetMemType(coo_i, &mtype));
4378:   if (PetscMemTypeDevice(mtype)) {
4379:     dev_ij = PETSC_TRUE;
4380:     PetscCall(PetscMalloc2(coo_n, &i, coo_n, &j));
4381:     PetscCallCUDA(cudaMemcpy(i, coo_i, coo_n * sizeof(PetscInt), cudaMemcpyDeviceToHost));
4382:     PetscCallCUDA(cudaMemcpy(j, coo_j, coo_n * sizeof(PetscInt), cudaMemcpyDeviceToHost));
4383:   } else {
4384:     i = coo_i;
4385:     j = coo_j;
4386:   }

4388:   PetscCall(MatSetPreallocationCOO_SeqAIJ(mat, coo_n, i, j));
4389:   if (dev_ij) PetscCall(PetscFree2(i, j));
4390:   mat->offloadmask = PETSC_OFFLOAD_CPU;
4391:   // Create the GPU memory
4392:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(mat));

4394:   // Copy the COO struct to device
4395:   PetscCall(PetscObjectQuery((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject *)&container_h));
4396:   PetscCall(PetscContainerGetPointer(container_h, (void **)&coo_h));
4397:   PetscCall(PetscMalloc1(1, &coo_d));
4398:   *coo_d = *coo_h; // do a shallow copy and then amend some fields that need to be different
4399:   PetscCallCUDA(cudaMalloc((void **)&coo_d->jmap, (coo_h->nz + 1) * sizeof(PetscCount)));
4400:   PetscCallCUDA(cudaMemcpy(coo_d->jmap, coo_h->jmap, (coo_h->nz + 1) * sizeof(PetscCount), cudaMemcpyHostToDevice));
4401:   PetscCallCUDA(cudaMalloc((void **)&coo_d->perm, coo_h->Atot * sizeof(PetscCount)));
4402:   PetscCallCUDA(cudaMemcpy(coo_d->perm, coo_h->perm, coo_h->Atot * sizeof(PetscCount), cudaMemcpyHostToDevice));

4404:   // Put the COO struct in a container and then attach that to the matrix
4405:   PetscCall(PetscObjectContainerCompose((PetscObject)mat, "__PETSc_MatCOOStruct_Device", coo_d, MatCOOStructDestroy_SeqAIJCUSPARSE));
4406:   PetscFunctionReturn(PETSC_SUCCESS);
4407: }

4409: __global__ static void MatAddCOOValues(const PetscScalar kv[], PetscCount nnz, const PetscCount jmap[], const PetscCount perm[], InsertMode imode, PetscScalar a[])
4410: {
4411:   PetscCount       i         = blockIdx.x * blockDim.x + threadIdx.x;
4412:   const PetscCount grid_size = gridDim.x * blockDim.x;
4413:   for (; i < nnz; i += grid_size) {
4414:     PetscScalar sum = 0.0;
4415:     for (PetscCount k = jmap[i]; k < jmap[i + 1]; k++) sum += kv[perm[k]];
4416:     a[i] = (imode == INSERT_VALUES ? 0.0 : a[i]) + sum;
4417:   }
4418: }

4420: static PetscErrorCode MatSetValuesCOO_SeqAIJCUSPARSE(Mat A, const PetscScalar v[], InsertMode imode)
4421: {
4422:   Mat_SeqAIJ          *seq  = (Mat_SeqAIJ *)A->data;
4423:   Mat_SeqAIJCUSPARSE  *dev  = (Mat_SeqAIJCUSPARSE *)A->spptr;
4424:   PetscCount           Annz = seq->nz;
4425:   PetscMemType         memtype;
4426:   const PetscScalar   *v1 = v;
4427:   PetscScalar         *Aa;
4428:   PetscContainer       container;
4429:   MatCOOStruct_SeqAIJ *coo;

4431:   PetscFunctionBegin;
4432:   if (!dev->mat) PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));

4434:   PetscCall(PetscObjectQuery((PetscObject)A, "__PETSc_MatCOOStruct_Device", (PetscObject *)&container));
4435:   PetscCall(PetscContainerGetPointer(container, (void **)&coo));

4437:   PetscCall(PetscGetMemType(v, &memtype));
4438:   if (PetscMemTypeHost(memtype)) { /* If user gave v[] in host, we might need to copy it to device if any */
4439:     PetscCallCUDA(cudaMalloc((void **)&v1, coo->n * sizeof(PetscScalar)));
4440:     PetscCallCUDA(cudaMemcpy((void *)v1, v, coo->n * sizeof(PetscScalar), cudaMemcpyHostToDevice));
4441:   }

4443:   if (imode == INSERT_VALUES) PetscCall(MatSeqAIJCUSPARSEGetArrayWrite(A, &Aa));
4444:   else PetscCall(MatSeqAIJCUSPARSEGetArray(A, &Aa));

4446:   PetscCall(PetscLogGpuTimeBegin());
4447:   if (Annz) {
4448:     MatAddCOOValues<<<((int)(Annz + 255) / 256), 256>>>(v1, Annz, coo->jmap, coo->perm, imode, Aa);
4449:     PetscCallCUDA(cudaPeekAtLastError());
4450:   }
4451:   PetscCall(PetscLogGpuTimeEnd());

4453:   if (imode == INSERT_VALUES) PetscCall(MatSeqAIJCUSPARSERestoreArrayWrite(A, &Aa));
4454:   else PetscCall(MatSeqAIJCUSPARSERestoreArray(A, &Aa));

4456:   if (PetscMemTypeHost(memtype)) PetscCallCUDA(cudaFree((void *)v1));
4457:   PetscFunctionReturn(PETSC_SUCCESS);
4458: }

4460: /*@C
4461:   MatSeqAIJCUSPARSEGetIJ - returns the device row storage `i` and `j` indices for `MATSEQAIJCUSPARSE` matrices.

4463:   Not Collective

4465:   Input Parameters:
4466: + A          - the matrix
4467: - compressed - `PETSC_TRUE` or `PETSC_FALSE` indicating the matrix data structure should be always returned in compressed form

4469:   Output Parameters:
4470: + i - the CSR row pointers, these are always `int` even when PETSc is configured with `--with-64-bit-indices`
4471: - j - the CSR column indices, these are always `int` even when PETSc is configured with `--with-64-bit-indices`

4473:   Level: developer

4475:   Note:
4476:   When compressed is true, the CSR structure does not contain empty rows

4478: .seealso: [](ch_matrices), `Mat`, `MatSeqAIJCUSPARSERestoreIJ()`, `MatSeqAIJCUSPARSEGetArrayRead()`
4479: @*/
4480: PetscErrorCode MatSeqAIJCUSPARSEGetIJ(Mat A, PetscBool compressed, const int **i, const int **j)
4481: {
4482:   Mat_SeqAIJCUSPARSE *cusp = (Mat_SeqAIJCUSPARSE *)A->spptr;
4483:   CsrMatrix          *csr;
4484:   Mat_SeqAIJ         *a = (Mat_SeqAIJ *)A->data;

4486:   PetscFunctionBegin;
4488:   if (!i || !j) PetscFunctionReturn(PETSC_SUCCESS);
4489:   PetscCheckTypeName(A, MATSEQAIJCUSPARSE);
4490:   PetscCheck(cusp->format != MAT_CUSPARSE_ELL && cusp->format != MAT_CUSPARSE_HYB, PETSC_COMM_SELF, PETSC_ERR_SUP, "Not implemented");
4491:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));
4492:   PetscCheck(cusp->mat, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing Mat_SeqAIJCUSPARSEMultStruct");
4493:   csr = (CsrMatrix *)cusp->mat->mat;
4494:   if (i) {
4495:     if (!compressed && a->compressedrow.use) { /* need full row offset */
4496:       if (!cusp->rowoffsets_gpu) {
4497:         cusp->rowoffsets_gpu = new THRUSTINTARRAY32(A->rmap->n + 1);
4498:         cusp->rowoffsets_gpu->assign(a->i, a->i + A->rmap->n + 1);
4499:         PetscCall(PetscLogCpuToGpu((A->rmap->n + 1) * sizeof(PetscInt)));
4500:       }
4501:       *i = cusp->rowoffsets_gpu->data().get();
4502:     } else *i = csr->row_offsets->data().get();
4503:   }
4504:   if (j) *j = csr->column_indices->data().get();
4505:   PetscFunctionReturn(PETSC_SUCCESS);
4506: }

4508: /*@C
4509:   MatSeqAIJCUSPARSERestoreIJ - restore the device row storage `i` and `j` indices obtained with `MatSeqAIJCUSPARSEGetIJ()`

4511:   Not Collective

4513:   Input Parameters:
4514: + A          - the matrix
4515: . compressed - `PETSC_TRUE` or `PETSC_FALSE` indicating the matrix data structure should be always returned in compressed form
4516: . i          - the CSR row pointers
4517: - j          - the CSR column indices

4519:   Level: developer

4521: .seealso: [](ch_matrices), `Mat`, `MatSeqAIJCUSPARSEGetIJ()`
4522: @*/
4523: PetscErrorCode MatSeqAIJCUSPARSERestoreIJ(Mat A, PetscBool compressed, const int **i, const int **j)
4524: {
4525:   PetscFunctionBegin;
4527:   PetscCheckTypeName(A, MATSEQAIJCUSPARSE);
4528:   if (i) *i = NULL;
4529:   if (j) *j = NULL;
4530:   (void)compressed;
4531:   PetscFunctionReturn(PETSC_SUCCESS);
4532: }

4534: /*@C
4535:   MatSeqAIJCUSPARSEGetArrayRead - gives read-only access to the array where the device data for a `MATSEQAIJCUSPARSE` matrix nonzero entries are stored

4537:   Not Collective

4539:   Input Parameter:
4540: . A - a `MATSEQAIJCUSPARSE` matrix

4542:   Output Parameter:
4543: . a - pointer to the device data

4545:   Level: developer

4547:   Note:
4548:   Will trigger host-to-device copies if the most up-to-date matrix data is on the host

4550: .seealso: [](ch_matrices), `Mat`, `MatSeqAIJCUSPARSEGetArray()`, `MatSeqAIJCUSPARSEGetArrayWrite()`, `MatSeqAIJCUSPARSERestoreArrayRead()`
4551: @*/
4552: PetscErrorCode MatSeqAIJCUSPARSEGetArrayRead(Mat A, const PetscScalar **a)
4553: {
4554:   Mat_SeqAIJCUSPARSE *cusp = (Mat_SeqAIJCUSPARSE *)A->spptr;
4555:   CsrMatrix          *csr;

4557:   PetscFunctionBegin;
4559:   PetscAssertPointer(a, 2);
4560:   PetscCheckTypeName(A, MATSEQAIJCUSPARSE);
4561:   PetscCheck(cusp->format != MAT_CUSPARSE_ELL && cusp->format != MAT_CUSPARSE_HYB, PETSC_COMM_SELF, PETSC_ERR_SUP, "Not implemented");
4562:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));
4563:   PetscCheck(cusp->mat, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing Mat_SeqAIJCUSPARSEMultStruct");
4564:   csr = (CsrMatrix *)cusp->mat->mat;
4565:   PetscCheck(csr->values, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing CUDA memory");
4566:   *a = csr->values->data().get();
4567:   PetscFunctionReturn(PETSC_SUCCESS);
4568: }

4570: /*@C
4571:   MatSeqAIJCUSPARSERestoreArrayRead - restore the read-only access array obtained from `MatSeqAIJCUSPARSEGetArrayRead()`

4573:   Not Collective

4575:   Input Parameters:
4576: + A - a `MATSEQAIJCUSPARSE` matrix
4577: - a - pointer to the device data

4579:   Level: developer

4581: .seealso: [](ch_matrices), `Mat`, `MatSeqAIJCUSPARSEGetArrayRead()`
4582: @*/
4583: PetscErrorCode MatSeqAIJCUSPARSERestoreArrayRead(Mat A, const PetscScalar **a)
4584: {
4585:   PetscFunctionBegin;
4587:   PetscAssertPointer(a, 2);
4588:   PetscCheckTypeName(A, MATSEQAIJCUSPARSE);
4589:   *a = NULL;
4590:   PetscFunctionReturn(PETSC_SUCCESS);
4591: }

4593: /*@C
4594:   MatSeqAIJCUSPARSEGetArray - gives read-write access to the array where the device data for a `MATSEQAIJCUSPARSE` matrix is stored

4596:   Not Collective

4598:   Input Parameter:
4599: . A - a `MATSEQAIJCUSPARSE` matrix

4601:   Output Parameter:
4602: . a - pointer to the device data

4604:   Level: developer

4606:   Note:
4607:   Will trigger host-to-device copies if the most up-to-date matrix data is on the host

4609: .seealso: [](ch_matrices), `Mat`, `MatSeqAIJCUSPARSEGetArrayRead()`, `MatSeqAIJCUSPARSEGetArrayWrite()`, `MatSeqAIJCUSPARSERestoreArray()`
4610: @*/
4611: PetscErrorCode MatSeqAIJCUSPARSEGetArray(Mat A, PetscScalar **a)
4612: {
4613:   Mat_SeqAIJCUSPARSE *cusp = (Mat_SeqAIJCUSPARSE *)A->spptr;
4614:   CsrMatrix          *csr;

4616:   PetscFunctionBegin;
4618:   PetscAssertPointer(a, 2);
4619:   PetscCheckTypeName(A, MATSEQAIJCUSPARSE);
4620:   PetscCheck(cusp->format != MAT_CUSPARSE_ELL && cusp->format != MAT_CUSPARSE_HYB, PETSC_COMM_SELF, PETSC_ERR_SUP, "Not implemented");
4621:   PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));
4622:   PetscCheck(cusp->mat, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing Mat_SeqAIJCUSPARSEMultStruct");
4623:   csr = (CsrMatrix *)cusp->mat->mat;
4624:   PetscCheck(csr->values, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing CUDA memory");
4625:   *a             = csr->values->data().get();
4626:   A->offloadmask = PETSC_OFFLOAD_GPU;
4627:   PetscCall(MatSeqAIJCUSPARSEInvalidateTranspose(A, PETSC_FALSE));
4628:   PetscFunctionReturn(PETSC_SUCCESS);
4629: }
4630: /*@C
4631:   MatSeqAIJCUSPARSERestoreArray - restore the read-write access array obtained from `MatSeqAIJCUSPARSEGetArray()`

4633:   Not Collective

4635:   Input Parameters:
4636: + A - a `MATSEQAIJCUSPARSE` matrix
4637: - a - pointer to the device data

4639:   Level: developer

4641: .seealso: [](ch_matrices), `Mat`, `MatSeqAIJCUSPARSEGetArray()`
4642: @*/
4643: PetscErrorCode MatSeqAIJCUSPARSERestoreArray(Mat A, PetscScalar **a)
4644: {
4645:   PetscFunctionBegin;
4647:   PetscAssertPointer(a, 2);
4648:   PetscCheckTypeName(A, MATSEQAIJCUSPARSE);
4649:   PetscCall(PetscObjectStateIncrease((PetscObject)A));
4650:   *a = NULL;
4651:   PetscFunctionReturn(PETSC_SUCCESS);
4652: }

4654: /*@C
4655:   MatSeqAIJCUSPARSEGetArrayWrite - gives write access to the array where the device data for a `MATSEQAIJCUSPARSE` matrix is stored

4657:   Not Collective

4659:   Input Parameter:
4660: . A - a `MATSEQAIJCUSPARSE` matrix

4662:   Output Parameter:
4663: . a - pointer to the device data

4665:   Level: developer

4667:   Note:
4668:   Does not trigger any host to device copies.

4670:   It marks the data GPU valid so users must set all the values in `a` to ensure out-of-date data is not considered current

4672: .seealso: [](ch_matrices), `Mat`, `MatSeqAIJCUSPARSEGetArray()`, `MatSeqAIJCUSPARSEGetArrayRead()`, `MatSeqAIJCUSPARSERestoreArrayWrite()`
4673: @*/
4674: PetscErrorCode MatSeqAIJCUSPARSEGetArrayWrite(Mat A, PetscScalar **a)
4675: {
4676:   Mat_SeqAIJCUSPARSE *cusp = (Mat_SeqAIJCUSPARSE *)A->spptr;
4677:   CsrMatrix          *csr;

4679:   PetscFunctionBegin;
4681:   PetscAssertPointer(a, 2);
4682:   PetscCheckTypeName(A, MATSEQAIJCUSPARSE);
4683:   PetscCheck(cusp->format != MAT_CUSPARSE_ELL && cusp->format != MAT_CUSPARSE_HYB, PETSC_COMM_SELF, PETSC_ERR_SUP, "Not implemented");
4684:   PetscCheck(cusp->mat, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing Mat_SeqAIJCUSPARSEMultStruct");
4685:   csr = (CsrMatrix *)cusp->mat->mat;
4686:   PetscCheck(csr->values, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing CUDA memory");
4687:   *a             = csr->values->data().get();
4688:   A->offloadmask = PETSC_OFFLOAD_GPU;
4689:   PetscCall(MatSeqAIJCUSPARSEInvalidateTranspose(A, PETSC_FALSE));
4690:   PetscFunctionReturn(PETSC_SUCCESS);
4691: }

4693: /*@C
4694:   MatSeqAIJCUSPARSERestoreArrayWrite - restore the write-only access array obtained from `MatSeqAIJCUSPARSEGetArrayWrite()`

4696:   Not Collective

4698:   Input Parameters:
4699: + A - a `MATSEQAIJCUSPARSE` matrix
4700: - a - pointer to the device data

4702:   Level: developer

4704: .seealso: [](ch_matrices), `Mat`, `MatSeqAIJCUSPARSEGetArrayWrite()`
4705: @*/
4706: PetscErrorCode MatSeqAIJCUSPARSERestoreArrayWrite(Mat A, PetscScalar **a)
4707: {
4708:   PetscFunctionBegin;
4710:   PetscAssertPointer(a, 2);
4711:   PetscCheckTypeName(A, MATSEQAIJCUSPARSE);
4712:   PetscCall(PetscObjectStateIncrease((PetscObject)A));
4713:   *a = NULL;
4714:   PetscFunctionReturn(PETSC_SUCCESS);
4715: }

4717: struct IJCompare4 {
4718:   __host__ __device__ inline bool operator()(const thrust::tuple<int, int, PetscScalar, int> &t1, const thrust::tuple<int, int, PetscScalar, int> &t2)
4719:   {
4720:     if (thrust::get<0>(t1) < thrust::get<0>(t2)) return true;
4721:     if (thrust::get<0>(t1) == thrust::get<0>(t2)) return thrust::get<1>(t1) < thrust::get<1>(t2);
4722:     return false;
4723:   }
4724: };

4726: struct Shift {
4727:   int _shift;

4729:   Shift(int shift) : _shift(shift) { }
4730:   __host__ __device__ inline int operator()(const int &c) { return c + _shift; }
4731: };

4733: /* merges two SeqAIJCUSPARSE matrices A, B by concatenating their rows. [A';B']' operation in MATLAB notation */
4734: PetscErrorCode MatSeqAIJCUSPARSEMergeMats(Mat A, Mat B, MatReuse reuse, Mat *C)
4735: {
4736:   Mat_SeqAIJ                   *a = (Mat_SeqAIJ *)A->data, *b = (Mat_SeqAIJ *)B->data, *c;
4737:   Mat_SeqAIJCUSPARSE           *Acusp = (Mat_SeqAIJCUSPARSE *)A->spptr, *Bcusp = (Mat_SeqAIJCUSPARSE *)B->spptr, *Ccusp;
4738:   Mat_SeqAIJCUSPARSEMultStruct *Cmat;
4739:   CsrMatrix                    *Acsr, *Bcsr, *Ccsr;
4740:   PetscInt                      Annz, Bnnz;
4741:   cusparseStatus_t              stat;
4742:   PetscInt                      i, m, n, zero = 0;

4744:   PetscFunctionBegin;
4747:   PetscAssertPointer(C, 4);
4748:   PetscCheckTypeName(A, MATSEQAIJCUSPARSE);
4749:   PetscCheckTypeName(B, MATSEQAIJCUSPARSE);
4750:   PetscCheck(A->rmap->n == B->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Invalid number or rows %" PetscInt_FMT " != %" PetscInt_FMT, A->rmap->n, B->rmap->n);
4751:   PetscCheck(reuse != MAT_INPLACE_MATRIX, PETSC_COMM_SELF, PETSC_ERR_SUP, "MAT_INPLACE_MATRIX not supported");
4752:   PetscCheck(Acusp->format != MAT_CUSPARSE_ELL && Acusp->format != MAT_CUSPARSE_HYB, PETSC_COMM_SELF, PETSC_ERR_SUP, "Not implemented");
4753:   PetscCheck(Bcusp->format != MAT_CUSPARSE_ELL && Bcusp->format != MAT_CUSPARSE_HYB, PETSC_COMM_SELF, PETSC_ERR_SUP, "Not implemented");
4754:   if (reuse == MAT_INITIAL_MATRIX) {
4755:     m = A->rmap->n;
4756:     n = A->cmap->n + B->cmap->n;
4757:     PetscCall(MatCreate(PETSC_COMM_SELF, C));
4758:     PetscCall(MatSetSizes(*C, m, n, m, n));
4759:     PetscCall(MatSetType(*C, MATSEQAIJCUSPARSE));
4760:     c                       = (Mat_SeqAIJ *)(*C)->data;
4761:     Ccusp                   = (Mat_SeqAIJCUSPARSE *)(*C)->spptr;
4762:     Cmat                    = new Mat_SeqAIJCUSPARSEMultStruct;
4763:     Ccsr                    = new CsrMatrix;
4764:     Cmat->cprowIndices      = NULL;
4765:     c->compressedrow.use    = PETSC_FALSE;
4766:     c->compressedrow.nrows  = 0;
4767:     c->compressedrow.i      = NULL;
4768:     c->compressedrow.rindex = NULL;
4769:     Ccusp->workVector       = NULL;
4770:     Ccusp->nrows            = m;
4771:     Ccusp->mat              = Cmat;
4772:     Ccusp->mat->mat         = Ccsr;
4773:     Ccsr->num_rows          = m;
4774:     Ccsr->num_cols          = n;
4775:     PetscCallCUSPARSE(cusparseCreateMatDescr(&Cmat->descr));
4776:     PetscCallCUSPARSE(cusparseSetMatIndexBase(Cmat->descr, CUSPARSE_INDEX_BASE_ZERO));
4777:     PetscCallCUSPARSE(cusparseSetMatType(Cmat->descr, CUSPARSE_MATRIX_TYPE_GENERAL));
4778:     PetscCallCUDA(cudaMalloc((void **)&Cmat->alpha_one, sizeof(PetscScalar)));
4779:     PetscCallCUDA(cudaMalloc((void **)&Cmat->beta_zero, sizeof(PetscScalar)));
4780:     PetscCallCUDA(cudaMalloc((void **)&Cmat->beta_one, sizeof(PetscScalar)));
4781:     PetscCallCUDA(cudaMemcpy(Cmat->alpha_one, &PETSC_CUSPARSE_ONE, sizeof(PetscScalar), cudaMemcpyHostToDevice));
4782:     PetscCallCUDA(cudaMemcpy(Cmat->beta_zero, &PETSC_CUSPARSE_ZERO, sizeof(PetscScalar), cudaMemcpyHostToDevice));
4783:     PetscCallCUDA(cudaMemcpy(Cmat->beta_one, &PETSC_CUSPARSE_ONE, sizeof(PetscScalar), cudaMemcpyHostToDevice));
4784:     PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));
4785:     PetscCall(MatSeqAIJCUSPARSECopyToGPU(B));
4786:     PetscCheck(Acusp->mat, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing Mat_SeqAIJCUSPARSEMultStruct");
4787:     PetscCheck(Bcusp->mat, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing Mat_SeqAIJCUSPARSEMultStruct");

4789:     Acsr                 = (CsrMatrix *)Acusp->mat->mat;
4790:     Bcsr                 = (CsrMatrix *)Bcusp->mat->mat;
4791:     Annz                 = (PetscInt)Acsr->column_indices->size();
4792:     Bnnz                 = (PetscInt)Bcsr->column_indices->size();
4793:     c->nz                = Annz + Bnnz;
4794:     Ccsr->row_offsets    = new THRUSTINTARRAY32(m + 1);
4795:     Ccsr->column_indices = new THRUSTINTARRAY32(c->nz);
4796:     Ccsr->values         = new THRUSTARRAY(c->nz);
4797:     Ccsr->num_entries    = c->nz;
4798:     Ccusp->coords        = new THRUSTINTARRAY(c->nz);
4799:     if (c->nz) {
4800:       auto              Acoo = new THRUSTINTARRAY32(Annz);
4801:       auto              Bcoo = new THRUSTINTARRAY32(Bnnz);
4802:       auto              Ccoo = new THRUSTINTARRAY32(c->nz);
4803:       THRUSTINTARRAY32 *Aroff, *Broff;

4805:       if (a->compressedrow.use) { /* need full row offset */
4806:         if (!Acusp->rowoffsets_gpu) {
4807:           Acusp->rowoffsets_gpu = new THRUSTINTARRAY32(A->rmap->n + 1);
4808:           Acusp->rowoffsets_gpu->assign(a->i, a->i + A->rmap->n + 1);
4809:           PetscCall(PetscLogCpuToGpu((A->rmap->n + 1) * sizeof(PetscInt)));
4810:         }
4811:         Aroff = Acusp->rowoffsets_gpu;
4812:       } else Aroff = Acsr->row_offsets;
4813:       if (b->compressedrow.use) { /* need full row offset */
4814:         if (!Bcusp->rowoffsets_gpu) {
4815:           Bcusp->rowoffsets_gpu = new THRUSTINTARRAY32(B->rmap->n + 1);
4816:           Bcusp->rowoffsets_gpu->assign(b->i, b->i + B->rmap->n + 1);
4817:           PetscCall(PetscLogCpuToGpu((B->rmap->n + 1) * sizeof(PetscInt)));
4818:         }
4819:         Broff = Bcusp->rowoffsets_gpu;
4820:       } else Broff = Bcsr->row_offsets;
4821:       PetscCall(PetscLogGpuTimeBegin());
4822:       stat = cusparseXcsr2coo(Acusp->handle, Aroff->data().get(), Annz, m, Acoo->data().get(), CUSPARSE_INDEX_BASE_ZERO);
4823:       PetscCallCUSPARSE(stat);
4824:       stat = cusparseXcsr2coo(Bcusp->handle, Broff->data().get(), Bnnz, m, Bcoo->data().get(), CUSPARSE_INDEX_BASE_ZERO);
4825:       PetscCallCUSPARSE(stat);
4826:       /* Issues when using bool with large matrices on SUMMIT 10.2.89 */
4827:       auto Aperm = thrust::make_constant_iterator(1);
4828:       auto Bperm = thrust::make_constant_iterator(0);
4829: #if PETSC_PKG_CUDA_VERSION_GE(10, 0, 0)
4830:       auto Bcib = thrust::make_transform_iterator(Bcsr->column_indices->begin(), Shift(A->cmap->n));
4831:       auto Bcie = thrust::make_transform_iterator(Bcsr->column_indices->end(), Shift(A->cmap->n));
4832: #else
4833:       /* there are issues instantiating the merge operation using a transform iterator for the columns of B */
4834:       auto Bcib = Bcsr->column_indices->begin();
4835:       auto Bcie = Bcsr->column_indices->end();
4836:       thrust::transform(Bcib, Bcie, Bcib, Shift(A->cmap->n));
4837: #endif
4838:       auto wPerm = new THRUSTINTARRAY32(Annz + Bnnz);
4839:       auto Azb   = thrust::make_zip_iterator(thrust::make_tuple(Acoo->begin(), Acsr->column_indices->begin(), Acsr->values->begin(), Aperm));
4840:       auto Aze   = thrust::make_zip_iterator(thrust::make_tuple(Acoo->end(), Acsr->column_indices->end(), Acsr->values->end(), Aperm));
4841:       auto Bzb   = thrust::make_zip_iterator(thrust::make_tuple(Bcoo->begin(), Bcib, Bcsr->values->begin(), Bperm));
4842:       auto Bze   = thrust::make_zip_iterator(thrust::make_tuple(Bcoo->end(), Bcie, Bcsr->values->end(), Bperm));
4843:       auto Czb   = thrust::make_zip_iterator(thrust::make_tuple(Ccoo->begin(), Ccsr->column_indices->begin(), Ccsr->values->begin(), wPerm->begin()));
4844:       auto p1    = Ccusp->coords->begin();
4845:       auto p2    = Ccusp->coords->begin();
4846:       thrust::advance(p2, Annz);
4847:       PetscCallThrust(thrust::merge(thrust::device, Azb, Aze, Bzb, Bze, Czb, IJCompare4()));
4848: #if PETSC_PKG_CUDA_VERSION_LT(10, 0, 0)
4849:       thrust::transform(Bcib, Bcie, Bcib, Shift(-A->cmap->n));
4850: #endif
4851:       auto cci = thrust::make_counting_iterator(zero);
4852:       auto cce = thrust::make_counting_iterator(c->nz);
4853: #if 0 //Errors on SUMMIT cuda 11.1.0
4854:       PetscCallThrust(thrust::partition_copy(thrust::device,cci,cce,wPerm->begin(),p1,p2,thrust::identity<int>()));
4855: #else
4856:   #if PETSC_PKG_CUDA_VERSION_LT(12, 9, 0) || PetscDefined(HAVE_THRUST)
4857:       auto pred = thrust::identity<int>();
4858:   #else
4859:       auto pred = cuda::std::identity();
4860:   #endif
4861:       PetscCallThrust(thrust::copy_if(thrust::device, cci, cce, wPerm->begin(), p1, pred));
4862:       PetscCallThrust(thrust::remove_copy_if(thrust::device, cci, cce, wPerm->begin(), p2, pred));
4863: #endif
4864:       stat = cusparseXcoo2csr(Ccusp->handle, Ccoo->data().get(), c->nz, m, Ccsr->row_offsets->data().get(), CUSPARSE_INDEX_BASE_ZERO);
4865:       PetscCallCUSPARSE(stat);
4866:       PetscCall(PetscLogGpuTimeEnd());
4867:       delete wPerm;
4868:       delete Acoo;
4869:       delete Bcoo;
4870:       delete Ccoo;
4871: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
4872:       stat = cusparseCreateCsr(&Cmat->matDescr, Ccsr->num_rows, Ccsr->num_cols, Ccsr->num_entries, Ccsr->row_offsets->data().get(), Ccsr->column_indices->data().get(), Ccsr->values->data().get(), CUSPARSE_INDEX_32I, CUSPARSE_INDEX_32I, CUSPARSE_INDEX_BASE_ZERO, cusparse_scalartype);
4873:       PetscCallCUSPARSE(stat);
4874: #endif
4875:       if (A->form_explicit_transpose && B->form_explicit_transpose) { /* if A and B have the transpose, generate C transpose too */
4876:         PetscCall(MatSeqAIJCUSPARSEFormExplicitTranspose(A));
4877:         PetscCall(MatSeqAIJCUSPARSEFormExplicitTranspose(B));
4878:         PetscBool                     AT = Acusp->matTranspose ? PETSC_TRUE : PETSC_FALSE, BT = Bcusp->matTranspose ? PETSC_TRUE : PETSC_FALSE;
4879:         Mat_SeqAIJCUSPARSEMultStruct *CmatT = new Mat_SeqAIJCUSPARSEMultStruct;
4880:         CsrMatrix                    *CcsrT = new CsrMatrix;
4881:         CsrMatrix                    *AcsrT = AT ? (CsrMatrix *)Acusp->matTranspose->mat : NULL;
4882:         CsrMatrix                    *BcsrT = BT ? (CsrMatrix *)Bcusp->matTranspose->mat : NULL;

4884:         (*C)->form_explicit_transpose = PETSC_TRUE;
4885:         (*C)->transupdated            = PETSC_TRUE;
4886:         Ccusp->rowoffsets_gpu         = NULL;
4887:         CmatT->cprowIndices           = NULL;
4888:         CmatT->mat                    = CcsrT;
4889:         CcsrT->num_rows               = n;
4890:         CcsrT->num_cols               = m;
4891:         CcsrT->num_entries            = c->nz;

4893:         CcsrT->row_offsets    = new THRUSTINTARRAY32(n + 1);
4894:         CcsrT->column_indices = new THRUSTINTARRAY32(c->nz);
4895:         CcsrT->values         = new THRUSTARRAY(c->nz);

4897:         PetscCall(PetscLogGpuTimeBegin());
4898:         auto rT = CcsrT->row_offsets->begin();
4899:         if (AT) {
4900:           rT = thrust::copy(AcsrT->row_offsets->begin(), AcsrT->row_offsets->end(), rT);
4901:           thrust::advance(rT, -1);
4902:         }
4903:         if (BT) {
4904:           auto titb = thrust::make_transform_iterator(BcsrT->row_offsets->begin(), Shift(a->nz));
4905:           auto tite = thrust::make_transform_iterator(BcsrT->row_offsets->end(), Shift(a->nz));
4906:           thrust::copy(titb, tite, rT);
4907:         }
4908:         auto cT = CcsrT->column_indices->begin();
4909:         if (AT) cT = thrust::copy(AcsrT->column_indices->begin(), AcsrT->column_indices->end(), cT);
4910:         if (BT) thrust::copy(BcsrT->column_indices->begin(), BcsrT->column_indices->end(), cT);
4911:         auto vT = CcsrT->values->begin();
4912:         if (AT) vT = thrust::copy(AcsrT->values->begin(), AcsrT->values->end(), vT);
4913:         if (BT) thrust::copy(BcsrT->values->begin(), BcsrT->values->end(), vT);
4914:         PetscCall(PetscLogGpuTimeEnd());

4916:         PetscCallCUSPARSE(cusparseCreateMatDescr(&CmatT->descr));
4917:         PetscCallCUSPARSE(cusparseSetMatIndexBase(CmatT->descr, CUSPARSE_INDEX_BASE_ZERO));
4918:         PetscCallCUSPARSE(cusparseSetMatType(CmatT->descr, CUSPARSE_MATRIX_TYPE_GENERAL));
4919:         PetscCallCUDA(cudaMalloc((void **)&CmatT->alpha_one, sizeof(PetscScalar)));
4920:         PetscCallCUDA(cudaMalloc((void **)&CmatT->beta_zero, sizeof(PetscScalar)));
4921:         PetscCallCUDA(cudaMalloc((void **)&CmatT->beta_one, sizeof(PetscScalar)));
4922:         PetscCallCUDA(cudaMemcpy(CmatT->alpha_one, &PETSC_CUSPARSE_ONE, sizeof(PetscScalar), cudaMemcpyHostToDevice));
4923:         PetscCallCUDA(cudaMemcpy(CmatT->beta_zero, &PETSC_CUSPARSE_ZERO, sizeof(PetscScalar), cudaMemcpyHostToDevice));
4924:         PetscCallCUDA(cudaMemcpy(CmatT->beta_one, &PETSC_CUSPARSE_ONE, sizeof(PetscScalar), cudaMemcpyHostToDevice));
4925: #if PETSC_PKG_CUDA_VERSION_GE(11, 0, 0)
4926:         stat = cusparseCreateCsr(&CmatT->matDescr, CcsrT->num_rows, CcsrT->num_cols, CcsrT->num_entries, CcsrT->row_offsets->data().get(), CcsrT->column_indices->data().get(), CcsrT->values->data().get(), CUSPARSE_INDEX_32I, CUSPARSE_INDEX_32I, CUSPARSE_INDEX_BASE_ZERO, cusparse_scalartype);
4927:         PetscCallCUSPARSE(stat);
4928: #endif
4929:         Ccusp->matTranspose = CmatT;
4930:       }
4931:     }

4933:     c->free_a = PETSC_TRUE;
4934:     PetscCall(PetscShmgetAllocateArray(c->nz, sizeof(PetscInt), (void **)&c->j));
4935:     PetscCall(PetscShmgetAllocateArray(m + 1, sizeof(PetscInt), (void **)&c->i));
4936:     c->free_ij = PETSC_TRUE;
4937:     if (PetscDefined(USE_64BIT_INDICES)) { /* 32 to 64-bit conversion on the GPU and then copy to host (lazy) */
4938:       THRUSTINTARRAY ii(Ccsr->row_offsets->size());
4939:       THRUSTINTARRAY jj(Ccsr->column_indices->size());
4940:       ii = *Ccsr->row_offsets;
4941:       jj = *Ccsr->column_indices;
4942:       PetscCallCUDA(cudaMemcpy(c->i, ii.data().get(), Ccsr->row_offsets->size() * sizeof(PetscInt), cudaMemcpyDeviceToHost));
4943:       PetscCallCUDA(cudaMemcpy(c->j, jj.data().get(), Ccsr->column_indices->size() * sizeof(PetscInt), cudaMemcpyDeviceToHost));
4944:     } else {
4945:       PetscCallCUDA(cudaMemcpy(c->i, Ccsr->row_offsets->data().get(), Ccsr->row_offsets->size() * sizeof(PetscInt), cudaMemcpyDeviceToHost));
4946:       PetscCallCUDA(cudaMemcpy(c->j, Ccsr->column_indices->data().get(), Ccsr->column_indices->size() * sizeof(PetscInt), cudaMemcpyDeviceToHost));
4947:     }
4948:     PetscCall(PetscLogGpuToCpu((Ccsr->column_indices->size() + Ccsr->row_offsets->size()) * sizeof(PetscInt)));
4949:     PetscCall(PetscMalloc1(m, &c->ilen));
4950:     PetscCall(PetscMalloc1(m, &c->imax));
4951:     c->maxnz         = c->nz;
4952:     c->nonzerorowcnt = 0;
4953:     c->rmax          = 0;
4954:     for (i = 0; i < m; i++) {
4955:       const PetscInt nn = c->i[i + 1] - c->i[i];
4956:       c->ilen[i] = c->imax[i] = nn;
4957:       c->nonzerorowcnt += (PetscInt)!!nn;
4958:       c->rmax = PetscMax(c->rmax, nn);
4959:     }
4960:     PetscCall(PetscMalloc1(c->nz, &c->a));
4961:     (*C)->nonzerostate++;
4962:     PetscCall(PetscLayoutSetUp((*C)->rmap));
4963:     PetscCall(PetscLayoutSetUp((*C)->cmap));
4964:     Ccusp->nonzerostate = (*C)->nonzerostate;
4965:     (*C)->preallocated  = PETSC_TRUE;
4966:   } else {
4967:     PetscCheck((*C)->rmap->n == B->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Invalid number or rows %" PetscInt_FMT " != %" PetscInt_FMT, (*C)->rmap->n, B->rmap->n);
4968:     c = (Mat_SeqAIJ *)(*C)->data;
4969:     if (c->nz) {
4970:       Ccusp = (Mat_SeqAIJCUSPARSE *)(*C)->spptr;
4971:       PetscCheck(Ccusp->coords, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing coords");
4972:       PetscCheck(Ccusp->format != MAT_CUSPARSE_ELL && Ccusp->format != MAT_CUSPARSE_HYB, PETSC_COMM_SELF, PETSC_ERR_SUP, "Not implemented");
4973:       PetscCheck(Ccusp->nonzerostate == (*C)->nonzerostate, PETSC_COMM_SELF, PETSC_ERR_COR, "Wrong nonzerostate");
4974:       PetscCall(MatSeqAIJCUSPARSECopyToGPU(A));
4975:       PetscCall(MatSeqAIJCUSPARSECopyToGPU(B));
4976:       PetscCheck(Acusp->mat, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing Mat_SeqAIJCUSPARSEMultStruct");
4977:       PetscCheck(Bcusp->mat, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing Mat_SeqAIJCUSPARSEMultStruct");
4978:       Acsr = (CsrMatrix *)Acusp->mat->mat;
4979:       Bcsr = (CsrMatrix *)Bcusp->mat->mat;
4980:       Ccsr = (CsrMatrix *)Ccusp->mat->mat;
4981:       PetscCheck(Acsr->num_entries == (PetscInt)Acsr->values->size(), PETSC_COMM_SELF, PETSC_ERR_COR, "A nnz %" PetscInt_FMT " != %" PetscInt_FMT, Acsr->num_entries, (PetscInt)Acsr->values->size());
4982:       PetscCheck(Bcsr->num_entries == (PetscInt)Bcsr->values->size(), PETSC_COMM_SELF, PETSC_ERR_COR, "B nnz %" PetscInt_FMT " != %" PetscInt_FMT, Bcsr->num_entries, (PetscInt)Bcsr->values->size());
4983:       PetscCheck(Ccsr->num_entries == (PetscInt)Ccsr->values->size(), PETSC_COMM_SELF, PETSC_ERR_COR, "C nnz %" PetscInt_FMT " != %" PetscInt_FMT, Ccsr->num_entries, (PetscInt)Ccsr->values->size());
4984:       PetscCheck(Ccsr->num_entries == Acsr->num_entries + Bcsr->num_entries, PETSC_COMM_SELF, PETSC_ERR_COR, "C nnz %" PetscInt_FMT " != %" PetscInt_FMT " + %" PetscInt_FMT, Ccsr->num_entries, Acsr->num_entries, Bcsr->num_entries);
4985:       PetscCheck(Ccusp->coords->size() == Ccsr->values->size(), PETSC_COMM_SELF, PETSC_ERR_COR, "permSize %" PetscInt_FMT " != %" PetscInt_FMT, (PetscInt)Ccusp->coords->size(), (PetscInt)Ccsr->values->size());
4986:       auto pmid = Ccusp->coords->begin();
4987:       thrust::advance(pmid, Acsr->num_entries);
4988:       PetscCall(PetscLogGpuTimeBegin());
4989:       auto zibait = thrust::make_zip_iterator(thrust::make_tuple(Acsr->values->begin(), thrust::make_permutation_iterator(Ccsr->values->begin(), Ccusp->coords->begin())));
4990:       auto zieait = thrust::make_zip_iterator(thrust::make_tuple(Acsr->values->end(), thrust::make_permutation_iterator(Ccsr->values->begin(), pmid)));
4991:       thrust::for_each(zibait, zieait, VecCUDAEquals());
4992:       auto zibbit = thrust::make_zip_iterator(thrust::make_tuple(Bcsr->values->begin(), thrust::make_permutation_iterator(Ccsr->values->begin(), pmid)));
4993:       auto ziebit = thrust::make_zip_iterator(thrust::make_tuple(Bcsr->values->end(), thrust::make_permutation_iterator(Ccsr->values->begin(), Ccusp->coords->end())));
4994:       thrust::for_each(zibbit, ziebit, VecCUDAEquals());
4995:       PetscCall(MatSeqAIJCUSPARSEInvalidateTranspose(*C, PETSC_FALSE));
4996:       if (A->form_explicit_transpose && B->form_explicit_transpose && (*C)->form_explicit_transpose) {
4997:         PetscCheck(Ccusp->matTranspose, PETSC_COMM_SELF, PETSC_ERR_COR, "Missing transpose Mat_SeqAIJCUSPARSEMultStruct");
4998:         PetscBool  AT = Acusp->matTranspose ? PETSC_TRUE : PETSC_FALSE, BT = Bcusp->matTranspose ? PETSC_TRUE : PETSC_FALSE;
4999:         CsrMatrix *AcsrT = AT ? (CsrMatrix *)Acusp->matTranspose->mat : NULL;
5000:         CsrMatrix *BcsrT = BT ? (CsrMatrix *)Bcusp->matTranspose->mat : NULL;
5001:         CsrMatrix *CcsrT = (CsrMatrix *)Ccusp->matTranspose->mat;
5002:         auto       vT    = CcsrT->values->begin();
5003:         if (AT) vT = thrust::copy(AcsrT->values->begin(), AcsrT->values->end(), vT);
5004:         if (BT) thrust::copy(BcsrT->values->begin(), BcsrT->values->end(), vT);
5005:         (*C)->transupdated = PETSC_TRUE;
5006:       }
5007:       PetscCall(PetscLogGpuTimeEnd());
5008:     }
5009:   }
5010:   PetscCall(PetscObjectStateIncrease((PetscObject)*C));
5011:   (*C)->assembled     = PETSC_TRUE;
5012:   (*C)->was_assembled = PETSC_FALSE;
5013:   (*C)->offloadmask   = PETSC_OFFLOAD_GPU;
5014:   PetscFunctionReturn(PETSC_SUCCESS);
5015: }

5017: static PetscErrorCode MatSeqAIJCopySubArray_SeqAIJCUSPARSE(Mat A, PetscInt n, const PetscInt idx[], PetscScalar v[])
5018: {
5019:   bool               dmem;
5020:   const PetscScalar *av;

5022:   PetscFunctionBegin;
5023:   dmem = isCudaMem(v);
5024:   PetscCall(MatSeqAIJCUSPARSEGetArrayRead(A, &av));
5025:   if (n && idx) {
5026:     THRUSTINTARRAY widx(n);
5027:     widx.assign(idx, idx + n);
5028:     PetscCall(PetscLogCpuToGpu(n * sizeof(PetscInt)));

5030:     THRUSTARRAY                    *w = NULL;
5031:     thrust::device_ptr<PetscScalar> dv;
5032:     if (dmem) {
5033:       dv = thrust::device_pointer_cast(v);
5034:     } else {
5035:       w  = new THRUSTARRAY(n);
5036:       dv = w->data();
5037:     }
5038:     thrust::device_ptr<const PetscScalar> dav = thrust::device_pointer_cast(av);

5040:     auto zibit = thrust::make_zip_iterator(thrust::make_tuple(thrust::make_permutation_iterator(dav, widx.begin()), dv));
5041:     auto zieit = thrust::make_zip_iterator(thrust::make_tuple(thrust::make_permutation_iterator(dav, widx.end()), dv + n));
5042:     thrust::for_each(zibit, zieit, VecCUDAEquals());
5043:     if (w) PetscCallCUDA(cudaMemcpy(v, w->data().get(), n * sizeof(PetscScalar), cudaMemcpyDeviceToHost));
5044:     delete w;
5045:   } else {
5046:     PetscCallCUDA(cudaMemcpy(v, av, n * sizeof(PetscScalar), dmem ? cudaMemcpyDeviceToDevice : cudaMemcpyDeviceToHost));
5047:   }
5048:   if (!dmem) PetscCall(PetscLogCpuToGpu(n * sizeof(PetscScalar)));
5049:   PetscCall(MatSeqAIJCUSPARSERestoreArrayRead(A, &av));
5050:   PetscFunctionReturn(PETSC_SUCCESS);
5051: }