1 /* 2 GAMG geometric-algebric multigrid PC - Mark Adams 2011 3 */ 4 #include <petsc/private/matimpl.h> 5 #include <../src/ksp/pc/impls/gamg/gamg.h> /*I "petscpc.h" I*/ 6 #include <petsc/private/kspimpl.h> 7 8 // PetscClangLinter pragma disable: -fdoc-sowing-chars 9 /* 10 PCGAMGGetDataWithGhosts - Get array of local + ghost data with local data 11 hacks into Mat MPIAIJ so this must have size > 1 12 13 Input Parameters: 14 + Gmat - MPIAIJ matrix for scatters 15 . data_sz - number of data terms per node (# cols in output) 16 - data_in - column oriented local data of size nloc*data_sz 17 18 Output Parameters: 19 + a_stride - number of rows of output (locals+ghosts) 20 - a_data_out - output data with ghosts of size stride*data_sz 21 22 */ 23 PetscErrorCode PCGAMGGetDataWithGhosts(Mat Gmat, PetscInt data_sz, PetscReal data_in[], PetscInt *a_stride, PetscReal **a_data_out) 24 { 25 Vec tmp_crds; 26 Mat_MPIAIJ *mpimat; 27 PetscInt nnodes, num_ghosts, dir, kk, jj, my0, Iend, nloc; 28 PetscScalar *data_arr; 29 PetscReal *datas; 30 PetscBool isMPIAIJ; 31 32 PetscFunctionBegin; 33 PetscValidHeaderSpecific(Gmat, MAT_CLASSID, 1); 34 mpimat = (Mat_MPIAIJ *)Gmat->data; 35 PetscCall(PetscObjectBaseTypeCompare((PetscObject)Gmat, MATMPIAIJ, &isMPIAIJ)); 36 PetscCall(MatGetOwnershipRange(Gmat, &my0, &Iend)); 37 nloc = Iend - my0; 38 PetscCall(VecGetLocalSize(mpimat->lvec, &num_ghosts)); 39 nnodes = num_ghosts + nloc; 40 *a_stride = nnodes; 41 PetscCall(MatCreateVecs(Gmat, &tmp_crds, NULL)); 42 43 PetscCall(PetscMalloc1(data_sz * nnodes, &datas)); 44 for (dir = 0; dir < data_sz; dir++) { 45 /* set local, and global */ 46 for (kk = 0; kk < nloc; kk++) { 47 PetscInt gid = my0 + kk; 48 PetscScalar crd = (PetscScalar)data_in[dir * nloc + kk]; /* col oriented */ 49 datas[dir * nnodes + kk] = PetscRealPart(crd); // get local part now 50 51 PetscCall(VecSetValues(tmp_crds, 1, &gid, &crd, INSERT_VALUES)); 52 } 53 PetscCall(VecAssemblyBegin(tmp_crds)); 54 PetscCall(VecAssemblyEnd(tmp_crds)); 55 /* scatter / gather ghost data and add to end of output data */ 56 PetscCall(VecScatterBegin(mpimat->Mvctx, tmp_crds, mpimat->lvec, INSERT_VALUES, SCATTER_FORWARD)); 57 PetscCall(VecScatterEnd(mpimat->Mvctx, tmp_crds, mpimat->lvec, INSERT_VALUES, SCATTER_FORWARD)); 58 PetscCall(VecGetArray(mpimat->lvec, &data_arr)); 59 for (kk = nloc, jj = 0; jj < num_ghosts; kk++, jj++) datas[dir * nnodes + kk] = PetscRealPart(data_arr[jj]); 60 PetscCall(VecRestoreArray(mpimat->lvec, &data_arr)); 61 } 62 PetscCall(VecDestroy(&tmp_crds)); 63 *a_data_out = datas; 64 PetscFunctionReturn(PETSC_SUCCESS); 65 } 66 67 PetscErrorCode PCGAMGHashTableCreate(PetscInt a_size, PCGAMGHashTable *a_tab) 68 { 69 PetscInt kk; 70 71 PetscFunctionBegin; 72 a_tab->size = a_size; 73 PetscCall(PetscMalloc2(a_size, &a_tab->table, a_size, &a_tab->data)); 74 for (kk = 0; kk < a_size; kk++) a_tab->table[kk] = -1; 75 PetscFunctionReturn(PETSC_SUCCESS); 76 } 77 78 PetscErrorCode PCGAMGHashTableDestroy(PCGAMGHashTable *a_tab) 79 { 80 PetscFunctionBegin; 81 PetscCall(PetscFree2(a_tab->table, a_tab->data)); 82 PetscFunctionReturn(PETSC_SUCCESS); 83 } 84 85 PetscErrorCode PCGAMGHashTableAdd(PCGAMGHashTable *a_tab, PetscInt a_key, PetscInt a_data) 86 { 87 PetscInt kk, idx; 88 89 PetscFunctionBegin; 90 PetscCheck(a_key >= 0, PETSC_COMM_SELF, PETSC_ERR_USER, "Negative key %" PetscInt_FMT ".", a_key); 91 for (kk = 0, idx = GAMG_HASH(a_key); kk < a_tab->size; kk++, idx = (idx == (a_tab->size - 1)) ? 0 : idx + 1) { 92 if (a_tab->table[idx] == a_key) { 93 /* exists */ 94 a_tab->data[idx] = a_data; 95 break; 96 } else if (a_tab->table[idx] == -1) { 97 /* add */ 98 a_tab->table[idx] = a_key; 99 a_tab->data[idx] = a_data; 100 break; 101 } 102 } 103 if (kk == a_tab->size) { 104 /* this is not to efficient, waiting until completely full */ 105 PetscInt oldsize = a_tab->size, new_size = 2 * a_tab->size + 5, *oldtable = a_tab->table, *olddata = a_tab->data; 106 107 a_tab->size = new_size; 108 PetscCall(PetscMalloc2(a_tab->size, &a_tab->table, a_tab->size, &a_tab->data)); 109 for (kk = 0; kk < a_tab->size; kk++) a_tab->table[kk] = -1; 110 for (kk = 0; kk < oldsize; kk++) { 111 if (oldtable[kk] != -1) PetscCall(PCGAMGHashTableAdd(a_tab, oldtable[kk], olddata[kk])); 112 } 113 PetscCall(PetscFree2(oldtable, olddata)); 114 PetscCall(PCGAMGHashTableAdd(a_tab, a_key, a_data)); 115 } 116 PetscFunctionReturn(PETSC_SUCCESS); 117 } 118