xref: /petsc/src/ksp/pc/impls/bddc/bddcfetidp.c (revision ebead697dbf761eb322f829370bbe90b3bd93fa3)
1 #include <petsc/private/pcbddcimpl.h>
2 #include <petsc/private/pcbddcprivateimpl.h>
3 #include <petscblaslapack.h>
4 
5 static PetscErrorCode MatMult_BDdelta_deluxe_nonred(Mat A, Vec x, Vec y)
6 {
7   BDdelta_DN     ctx;
8 
9   PetscFunctionBegin;
10   PetscCall(MatShellGetContext(A,&ctx));
11   PetscCall(MatMultTranspose(ctx->BD,x,ctx->work));
12   PetscCall(KSPSolveTranspose(ctx->kBD,ctx->work,y));
13   /* No PC so cannot propagate up failure in KSPSolveTranspose() */
14   PetscFunctionReturn(0);
15 }
16 
17 static PetscErrorCode MatMultTranspose_BDdelta_deluxe_nonred(Mat A, Vec x, Vec y)
18 {
19   BDdelta_DN     ctx;
20 
21   PetscFunctionBegin;
22   PetscCall(MatShellGetContext(A,&ctx));
23   PetscCall(KSPSolve(ctx->kBD,x,ctx->work));
24   /* No PC so cannot propagate up failure in KSPSolve() */
25   PetscCall(MatMult(ctx->BD,ctx->work,y));
26   PetscFunctionReturn(0);
27 }
28 
29 static PetscErrorCode MatDestroy_BDdelta_deluxe_nonred(Mat A)
30 {
31   BDdelta_DN     ctx;
32 
33   PetscFunctionBegin;
34   PetscCall(MatShellGetContext(A,&ctx));
35   PetscCall(MatDestroy(&ctx->BD));
36   PetscCall(KSPDestroy(&ctx->kBD));
37   PetscCall(VecDestroy(&ctx->work));
38   PetscCall(PetscFree(ctx));
39   PetscFunctionReturn(0);
40 }
41 
42 PetscErrorCode PCBDDCCreateFETIDPMatContext(PC pc, FETIDPMat_ctx *fetidpmat_ctx)
43 {
44   FETIDPMat_ctx  newctx;
45 
46   PetscFunctionBegin;
47   PetscCall(PetscNew(&newctx));
48   /* increase the reference count for BDDC preconditioner */
49   PetscCall(PetscObjectReference((PetscObject)pc));
50   newctx->pc              = pc;
51   *fetidpmat_ctx          = newctx;
52   PetscFunctionReturn(0);
53 }
54 
55 PetscErrorCode PCBDDCCreateFETIDPPCContext(PC pc, FETIDPPC_ctx *fetidppc_ctx)
56 {
57   FETIDPPC_ctx   newctx;
58 
59   PetscFunctionBegin;
60   PetscCall(PetscNew(&newctx));
61   /* increase the reference count for BDDC preconditioner */
62   PetscCall(PetscObjectReference((PetscObject)pc));
63   newctx->pc              = pc;
64   *fetidppc_ctx           = newctx;
65   PetscFunctionReturn(0);
66 }
67 
68 PetscErrorCode PCBDDCDestroyFETIDPMat(Mat A)
69 {
70   FETIDPMat_ctx  mat_ctx;
71 
72   PetscFunctionBegin;
73   PetscCall(MatShellGetContext(A,&mat_ctx));
74   PetscCall(VecDestroy(&mat_ctx->lambda_local));
75   PetscCall(VecDestroy(&mat_ctx->temp_solution_D));
76   PetscCall(VecDestroy(&mat_ctx->temp_solution_B));
77   PetscCall(MatDestroy(&mat_ctx->B_delta));
78   PetscCall(MatDestroy(&mat_ctx->B_Ddelta));
79   PetscCall(MatDestroy(&mat_ctx->B_BB));
80   PetscCall(MatDestroy(&mat_ctx->B_BI));
81   PetscCall(MatDestroy(&mat_ctx->Bt_BB));
82   PetscCall(MatDestroy(&mat_ctx->Bt_BI));
83   PetscCall(MatDestroy(&mat_ctx->C));
84   PetscCall(VecDestroy(&mat_ctx->rhs_flip));
85   PetscCall(VecDestroy(&mat_ctx->vP));
86   PetscCall(VecDestroy(&mat_ctx->xPg));
87   PetscCall(VecDestroy(&mat_ctx->yPg));
88   PetscCall(VecScatterDestroy(&mat_ctx->l2g_lambda));
89   PetscCall(VecScatterDestroy(&mat_ctx->l2g_lambda_only));
90   PetscCall(VecScatterDestroy(&mat_ctx->l2g_p));
91   PetscCall(VecScatterDestroy(&mat_ctx->g2g_p));
92   PetscCall(PCDestroy(&mat_ctx->pc)); /* decrease PCBDDC reference count */
93   PetscCall(ISDestroy(&mat_ctx->pressure));
94   PetscCall(ISDestroy(&mat_ctx->lagrange));
95   PetscCall(PetscFree(mat_ctx));
96   PetscFunctionReturn(0);
97 }
98 
99 PetscErrorCode PCBDDCDestroyFETIDPPC(PC pc)
100 {
101   FETIDPPC_ctx   pc_ctx;
102 
103   PetscFunctionBegin;
104   PetscCall(PCShellGetContext(pc,&pc_ctx));
105   PetscCall(VecDestroy(&pc_ctx->lambda_local));
106   PetscCall(MatDestroy(&pc_ctx->B_Ddelta));
107   PetscCall(VecScatterDestroy(&pc_ctx->l2g_lambda));
108   PetscCall(MatDestroy(&pc_ctx->S_j));
109   PetscCall(PCDestroy(&pc_ctx->pc)); /* decrease PCBDDC reference count */
110   PetscCall(VecDestroy(&pc_ctx->xPg));
111   PetscCall(VecDestroy(&pc_ctx->yPg));
112   PetscCall(PetscFree(pc_ctx));
113   PetscFunctionReturn(0);
114 }
115 
116 PetscErrorCode PCBDDCSetupFETIDPMatContext(FETIDPMat_ctx fetidpmat_ctx)
117 {
118   PC_IS          *pcis=(PC_IS*)fetidpmat_ctx->pc->data;
119   PC_BDDC        *pcbddc=(PC_BDDC*)fetidpmat_ctx->pc->data;
120   PCBDDCGraph    mat_graph=pcbddc->mat_graph;
121   Mat_IS         *matis  = (Mat_IS*)fetidpmat_ctx->pc->pmat->data;
122   MPI_Comm       comm;
123   Mat            ScalingMat,BD1,BD2;
124   Vec            fetidp_global;
125   IS             IS_l2g_lambda;
126   IS             subset,subset_mult,subset_n,isvert;
127   PetscBool      skip_node,fully_redundant;
128   PetscInt       i,j,k,s,n_boundary_dofs,n_global_lambda,n_vertices,partial_sum;
129   PetscInt       cum,n_local_lambda,n_lambda_for_dof,dual_size,n_neg_values,n_pos_values;
130   PetscMPIInt    rank,size,buf_size,neigh;
131   PetscScalar    scalar_value;
132   const PetscInt *vertex_indices;
133   PetscInt       *dual_dofs_boundary_indices,*aux_local_numbering_1;
134   const PetscInt *aux_global_numbering;
135   PetscInt       *aux_sums,*cols_B_delta,*l2g_indices;
136   PetscScalar    *array,*scaling_factors,*vals_B_delta;
137   PetscScalar    **all_factors;
138   PetscInt       *aux_local_numbering_2;
139   PetscLayout    llay;
140 
141   /* saddlepoint */
142   ISLocalToGlobalMapping l2gmap_p;
143   PetscLayout            play;
144   IS                     gP,pP;
145   PetscInt               nPl,nPg,nPgl;
146 
147   PetscFunctionBegin;
148   PetscCall(PetscObjectGetComm((PetscObject)(fetidpmat_ctx->pc),&comm));
149   PetscCallMPI(MPI_Comm_rank(comm,&rank));
150   PetscCallMPI(MPI_Comm_size(comm,&size));
151 
152   /* saddlepoint */
153   nPl      = 0;
154   nPg      = 0;
155   nPgl     = 0;
156   gP       = NULL;
157   pP       = NULL;
158   l2gmap_p = NULL;
159   play     = NULL;
160   PetscCall(PetscObjectQuery((PetscObject)fetidpmat_ctx->pc,"__KSPFETIDP_pP",(PetscObject*)&pP));
161   if (pP) { /* saddle point */
162     /* subdomain pressures in global numbering */
163     PetscCall(PetscObjectQuery((PetscObject)fetidpmat_ctx->pc,"__KSPFETIDP_gP",(PetscObject*)&gP));
164     PetscCheck(gP,PETSC_COMM_SELF,PETSC_ERR_PLIB,"gP not present");
165     PetscCall(ISGetLocalSize(gP,&nPl));
166     PetscCall(VecCreate(PETSC_COMM_SELF,&fetidpmat_ctx->vP));
167     PetscCall(VecSetSizes(fetidpmat_ctx->vP,nPl,nPl));
168     PetscCall(VecSetType(fetidpmat_ctx->vP,VECSTANDARD));
169     PetscCall(VecSetUp(fetidpmat_ctx->vP));
170 
171     /* pressure matrix */
172     PetscCall(PetscObjectQuery((PetscObject)fetidpmat_ctx->pc,"__KSPFETIDP_C",(PetscObject*)&fetidpmat_ctx->C));
173     if (!fetidpmat_ctx->C) { /* null pressure block, compute layout and global numbering for pressures */
174       IS Pg;
175 
176       PetscCall(ISRenumber(gP,NULL,&nPg,&Pg));
177       PetscCall(ISLocalToGlobalMappingCreateIS(Pg,&l2gmap_p));
178       PetscCall(ISDestroy(&Pg));
179       PetscCall(PetscLayoutCreate(comm,&play));
180       PetscCall(PetscLayoutSetBlockSize(play,1));
181       PetscCall(PetscLayoutSetSize(play,nPg));
182       PetscCall(ISGetLocalSize(pP,&nPgl));
183       PetscCall(PetscLayoutSetLocalSize(play,nPgl));
184       PetscCall(PetscLayoutSetUp(play));
185     } else {
186       PetscCall(PetscObjectReference((PetscObject)fetidpmat_ctx->C));
187       PetscCall(MatISGetLocalToGlobalMapping(fetidpmat_ctx->C,&l2gmap_p,NULL));
188       PetscCall(PetscObjectReference((PetscObject)l2gmap_p));
189       PetscCall(MatGetSize(fetidpmat_ctx->C,&nPg,NULL));
190       PetscCall(MatGetLocalSize(fetidpmat_ctx->C,NULL,&nPgl));
191       PetscCall(MatGetLayouts(fetidpmat_ctx->C,NULL,&llay));
192       PetscCall(PetscLayoutReference(llay,&play));
193     }
194     PetscCall(VecCreateMPIWithArray(comm,1,nPgl,nPg,NULL,&fetidpmat_ctx->xPg));
195     PetscCall(VecCreateMPIWithArray(comm,1,nPgl,nPg,NULL,&fetidpmat_ctx->yPg));
196 
197     /* import matrices for pressures coupling */
198     PetscCall(PetscObjectQuery((PetscObject)fetidpmat_ctx->pc,"__KSPFETIDP_B_BI",(PetscObject*)&fetidpmat_ctx->B_BI));
199     PetscCheck(fetidpmat_ctx->B_BI,PETSC_COMM_SELF,PETSC_ERR_PLIB,"B_BI not present");
200     PetscCall(PetscObjectReference((PetscObject)fetidpmat_ctx->B_BI));
201 
202     PetscCall(PetscObjectQuery((PetscObject)fetidpmat_ctx->pc,"__KSPFETIDP_B_BB",(PetscObject*)&fetidpmat_ctx->B_BB));
203     PetscCheck(fetidpmat_ctx->B_BB,PETSC_COMM_SELF,PETSC_ERR_PLIB,"B_BB not present");
204     PetscCall(PetscObjectReference((PetscObject)fetidpmat_ctx->B_BB));
205 
206     PetscCall(PetscObjectQuery((PetscObject)fetidpmat_ctx->pc,"__KSPFETIDP_Bt_BI",(PetscObject*)&fetidpmat_ctx->Bt_BI));
207     PetscCheck(fetidpmat_ctx->Bt_BI,PETSC_COMM_SELF,PETSC_ERR_PLIB,"Bt_BI not present");
208     PetscCall(PetscObjectReference((PetscObject)fetidpmat_ctx->Bt_BI));
209 
210     PetscCall(PetscObjectQuery((PetscObject)fetidpmat_ctx->pc,"__KSPFETIDP_Bt_BB",(PetscObject*)&fetidpmat_ctx->Bt_BB));
211     PetscCheck(fetidpmat_ctx->Bt_BB,PETSC_COMM_SELF,PETSC_ERR_PLIB,"Bt_BB not present");
212     PetscCall(PetscObjectReference((PetscObject)fetidpmat_ctx->Bt_BB));
213 
214     PetscCall(PetscObjectQuery((PetscObject)fetidpmat_ctx->pc,"__KSPFETIDP_flip" ,(PetscObject*)&fetidpmat_ctx->rhs_flip));
215     if (fetidpmat_ctx->rhs_flip) PetscCall(PetscObjectReference((PetscObject)fetidpmat_ctx->rhs_flip));
216   }
217 
218   /* Default type of lagrange multipliers is non-redundant */
219   fully_redundant = fetidpmat_ctx->fully_redundant;
220 
221   /* Evaluate local and global number of lagrange multipliers */
222   PetscCall(VecSet(pcis->vec1_N,0.0));
223   n_local_lambda = 0;
224   partial_sum = 0;
225   n_boundary_dofs = 0;
226   s = 0;
227 
228   /* Get Vertices used to define the BDDC */
229   PetscCall(PCBDDCGraphGetCandidatesIS(pcbddc->mat_graph,NULL,NULL,NULL,NULL,&isvert));
230   PetscCall(ISGetLocalSize(isvert,&n_vertices));
231   PetscCall(ISGetIndices(isvert,&vertex_indices));
232 
233   dual_size = pcis->n_B-n_vertices;
234   PetscCall(PetscMalloc1(dual_size,&dual_dofs_boundary_indices));
235   PetscCall(PetscMalloc1(dual_size,&aux_local_numbering_1));
236   PetscCall(PetscMalloc1(dual_size,&aux_local_numbering_2));
237 
238   PetscCall(VecGetArray(pcis->vec1_N,&array));
239   for (i=0;i<pcis->n;i++) {
240     j = mat_graph->count[i]; /* RECALL: mat_graph->count[i] does not count myself */
241     if (j > 0) n_boundary_dofs++;
242     skip_node = PETSC_FALSE;
243     if (s < n_vertices && vertex_indices[s] == i) { /* it works for a sorted set of vertices */
244       skip_node = PETSC_TRUE;
245       s++;
246     }
247     if (j < 1) skip_node = PETSC_TRUE;
248     if (mat_graph->special_dof[i] == PCBDDCGRAPH_DIRICHLET_MARK) skip_node = PETSC_TRUE;
249     if (!skip_node) {
250       if (fully_redundant) {
251         /* fully redundant set of lagrange multipliers */
252         n_lambda_for_dof = (j*(j+1))/2;
253       } else {
254         n_lambda_for_dof = j;
255       }
256       n_local_lambda += j;
257       /* needed to evaluate global number of lagrange multipliers */
258       array[i]=(1.0*n_lambda_for_dof)/(j+1.0); /* already scaled for the next global sum */
259       /* store some data needed */
260       dual_dofs_boundary_indices[partial_sum] = n_boundary_dofs-1;
261       aux_local_numbering_1[partial_sum] = i;
262       aux_local_numbering_2[partial_sum] = n_lambda_for_dof;
263       partial_sum++;
264     }
265   }
266   PetscCall(VecRestoreArray(pcis->vec1_N,&array));
267   PetscCall(ISRestoreIndices(isvert,&vertex_indices));
268   PetscCall(PCBDDCGraphRestoreCandidatesIS(pcbddc->mat_graph,NULL,NULL,NULL,NULL,&isvert));
269   dual_size = partial_sum;
270 
271   /* compute global ordering of lagrange multipliers and associate l2g map */
272   PetscCall(ISCreateGeneral(comm,partial_sum,aux_local_numbering_1,PETSC_COPY_VALUES,&subset_n));
273   PetscCall(ISLocalToGlobalMappingApplyIS(pcis->mapping,subset_n,&subset));
274   PetscCall(ISDestroy(&subset_n));
275   PetscCall(ISCreateGeneral(comm,partial_sum,aux_local_numbering_2,PETSC_OWN_POINTER,&subset_mult));
276   PetscCall(ISRenumber(subset,subset_mult,&fetidpmat_ctx->n_lambda,&subset_n));
277   PetscCall(ISDestroy(&subset));
278 
279   if (PetscDefined(USE_DEBUG)) {
280     PetscCall(VecSet(pcis->vec1_global,0.0));
281     PetscCall(VecScatterBegin(matis->rctx,pcis->vec1_N,pcis->vec1_global,ADD_VALUES,SCATTER_REVERSE));
282     PetscCall(VecScatterEnd(matis->rctx,pcis->vec1_N,pcis->vec1_global,ADD_VALUES,SCATTER_REVERSE));
283     PetscCall(VecSum(pcis->vec1_global,&scalar_value));
284     i = (PetscInt)PetscRealPart(scalar_value);
285     PetscCheck(i == fetidpmat_ctx->n_lambda,PETSC_COMM_WORLD,PETSC_ERR_PLIB,"Global number of multipliers mismatch! (%" PetscInt_FMT " != %" PetscInt_FMT ")",fetidpmat_ctx->n_lambda,i);
286   }
287 
288   /* init data for scaling factors exchange */
289   if (!pcbddc->use_deluxe_scaling) {
290     PetscInt    *ptrs_buffer,neigh_position;
291     PetscScalar *send_buffer,*recv_buffer;
292     MPI_Request *send_reqs,*recv_reqs;
293 
294     partial_sum = 0;
295     PetscCall(PetscMalloc1(pcis->n_neigh,&ptrs_buffer));
296     PetscCall(PetscMalloc1(PetscMax(pcis->n_neigh-1,0),&send_reqs));
297     PetscCall(PetscMalloc1(PetscMax(pcis->n_neigh-1,0),&recv_reqs));
298     PetscCall(PetscMalloc1(pcis->n+1,&all_factors));
299     if (pcis->n_neigh > 0) ptrs_buffer[0]=0;
300     for (i=1;i<pcis->n_neigh;i++) {
301       partial_sum += pcis->n_shared[i];
302       ptrs_buffer[i] = ptrs_buffer[i-1]+pcis->n_shared[i];
303     }
304     PetscCall(PetscMalloc1(partial_sum,&send_buffer));
305     PetscCall(PetscMalloc1(partial_sum,&recv_buffer));
306     PetscCall(PetscMalloc1(partial_sum,&all_factors[0]));
307     for (i=0;i<pcis->n-1;i++) {
308       j = mat_graph->count[i];
309       all_factors[i+1]=all_factors[i]+j;
310     }
311 
312     /* scatter B scaling to N vec */
313     PetscCall(VecScatterBegin(pcis->N_to_B,pcis->D,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE));
314     PetscCall(VecScatterEnd(pcis->N_to_B,pcis->D,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE));
315     /* communications */
316     PetscCall(VecGetArrayRead(pcis->vec1_N,(const PetscScalar**)&array));
317     for (i=1;i<pcis->n_neigh;i++) {
318       for (j=0;j<pcis->n_shared[i];j++) {
319         send_buffer[ptrs_buffer[i-1]+j]=array[pcis->shared[i][j]];
320       }
321       PetscCall(PetscMPIIntCast(ptrs_buffer[i]-ptrs_buffer[i-1],&buf_size));
322       PetscCall(PetscMPIIntCast(pcis->neigh[i],&neigh));
323       PetscCallMPI(MPI_Isend(&send_buffer[ptrs_buffer[i-1]],buf_size,MPIU_SCALAR,neigh,0,comm,&send_reqs[i-1]));
324       PetscCallMPI(MPI_Irecv(&recv_buffer[ptrs_buffer[i-1]],buf_size,MPIU_SCALAR,neigh,0,comm,&recv_reqs[i-1]));
325     }
326     PetscCall(VecRestoreArrayRead(pcis->vec1_N,(const PetscScalar**)&array));
327     if (pcis->n_neigh > 0) {
328       PetscCallMPI(MPI_Waitall(pcis->n_neigh-1,recv_reqs,MPI_STATUSES_IGNORE));
329     }
330     /* put values in correct places */
331     for (i=1;i<pcis->n_neigh;i++) {
332       for (j=0;j<pcis->n_shared[i];j++) {
333         k = pcis->shared[i][j];
334         neigh_position = 0;
335         while (mat_graph->neighbours_set[k][neigh_position] != pcis->neigh[i]) {neigh_position++;}
336         all_factors[k][neigh_position]=recv_buffer[ptrs_buffer[i-1]+j];
337       }
338     }
339     if (pcis->n_neigh > 0) {
340       PetscCallMPI(MPI_Waitall(pcis->n_neigh-1,send_reqs,MPI_STATUSES_IGNORE));
341     }
342     PetscCall(PetscFree(send_reqs));
343     PetscCall(PetscFree(recv_reqs));
344     PetscCall(PetscFree(send_buffer));
345     PetscCall(PetscFree(recv_buffer));
346     PetscCall(PetscFree(ptrs_buffer));
347   }
348 
349   /* Compute B and B_delta (local actions) */
350   PetscCall(PetscMalloc1(pcis->n_neigh,&aux_sums));
351   PetscCall(PetscMalloc1(n_local_lambda,&l2g_indices));
352   PetscCall(PetscMalloc1(n_local_lambda,&vals_B_delta));
353   PetscCall(PetscMalloc1(n_local_lambda,&cols_B_delta));
354   if (!pcbddc->use_deluxe_scaling) {
355     PetscCall(PetscMalloc1(n_local_lambda,&scaling_factors));
356   } else {
357     scaling_factors = NULL;
358     all_factors     = NULL;
359   }
360   PetscCall(ISGetIndices(subset_n,&aux_global_numbering));
361   partial_sum=0;
362   cum = 0;
363   for (i=0;i<dual_size;i++) {
364     n_global_lambda = aux_global_numbering[cum];
365     j = mat_graph->count[aux_local_numbering_1[i]];
366     aux_sums[0]=0;
367     for (s=1;s<j;s++) {
368       aux_sums[s]=aux_sums[s-1]+j-s+1;
369     }
370     if (all_factors) array = all_factors[aux_local_numbering_1[i]];
371     n_neg_values = 0;
372     while (n_neg_values < j && mat_graph->neighbours_set[aux_local_numbering_1[i]][n_neg_values] < rank) {n_neg_values++;}
373     n_pos_values = j - n_neg_values;
374     if (fully_redundant) {
375       for (s=0;s<n_neg_values;s++) {
376         l2g_indices    [partial_sum+s]=aux_sums[s]+n_neg_values-s-1+n_global_lambda;
377         cols_B_delta   [partial_sum+s]=dual_dofs_boundary_indices[i];
378         vals_B_delta   [partial_sum+s]=-1.0;
379         if (!pcbddc->use_deluxe_scaling) scaling_factors[partial_sum+s]=array[s];
380       }
381       for (s=0;s<n_pos_values;s++) {
382         l2g_indices    [partial_sum+s+n_neg_values]=aux_sums[n_neg_values]+s+n_global_lambda;
383         cols_B_delta   [partial_sum+s+n_neg_values]=dual_dofs_boundary_indices[i];
384         vals_B_delta   [partial_sum+s+n_neg_values]=1.0;
385         if (!pcbddc->use_deluxe_scaling) scaling_factors[partial_sum+s+n_neg_values]=array[s+n_neg_values];
386       }
387       partial_sum += j;
388     } else {
389       /* l2g_indices and default cols and vals of B_delta */
390       for (s=0;s<j;s++) {
391         l2g_indices    [partial_sum+s]=n_global_lambda+s;
392         cols_B_delta   [partial_sum+s]=dual_dofs_boundary_indices[i];
393         vals_B_delta   [partial_sum+s]=0.0;
394       }
395       /* B_delta */
396       if (n_neg_values > 0) { /* there's a rank next to me to the left */
397         vals_B_delta   [partial_sum+n_neg_values-1]=-1.0;
398       }
399       if (n_neg_values < j) { /* there's a rank next to me to the right */
400         vals_B_delta   [partial_sum+n_neg_values]=1.0;
401       }
402       /* scaling as in Klawonn-Widlund 1999 */
403       if (!pcbddc->use_deluxe_scaling) {
404         for (s=0;s<n_neg_values;s++) {
405           scalar_value = 0.0;
406           for (k=0;k<s+1;k++) scalar_value += array[k];
407           scaling_factors[partial_sum+s] = -scalar_value;
408         }
409         for (s=0;s<n_pos_values;s++) {
410           scalar_value = 0.0;
411           for (k=s+n_neg_values;k<j;k++) scalar_value += array[k];
412           scaling_factors[partial_sum+s+n_neg_values] = scalar_value;
413         }
414       }
415       partial_sum += j;
416     }
417     cum += aux_local_numbering_2[i];
418   }
419   PetscCall(ISRestoreIndices(subset_n,&aux_global_numbering));
420   PetscCall(ISDestroy(&subset_mult));
421   PetscCall(ISDestroy(&subset_n));
422   PetscCall(PetscFree(aux_sums));
423   PetscCall(PetscFree(aux_local_numbering_1));
424   PetscCall(PetscFree(dual_dofs_boundary_indices));
425   if (all_factors) {
426     PetscCall(PetscFree(all_factors[0]));
427     PetscCall(PetscFree(all_factors));
428   }
429 
430   /* Create local part of B_delta */
431   PetscCall(MatCreate(PETSC_COMM_SELF,&fetidpmat_ctx->B_delta));
432   PetscCall(MatSetSizes(fetidpmat_ctx->B_delta,n_local_lambda,pcis->n_B,n_local_lambda,pcis->n_B));
433   PetscCall(MatSetType(fetidpmat_ctx->B_delta,MATSEQAIJ));
434   PetscCall(MatSeqAIJSetPreallocation(fetidpmat_ctx->B_delta,1,NULL));
435   PetscCall(MatSetOption(fetidpmat_ctx->B_delta,MAT_IGNORE_ZERO_ENTRIES,PETSC_TRUE));
436   for (i=0;i<n_local_lambda;i++) {
437     PetscCall(MatSetValue(fetidpmat_ctx->B_delta,i,cols_B_delta[i],vals_B_delta[i],INSERT_VALUES));
438   }
439   PetscCall(PetscFree(vals_B_delta));
440   PetscCall(MatAssemblyBegin(fetidpmat_ctx->B_delta,MAT_FINAL_ASSEMBLY));
441   PetscCall(MatAssemblyEnd(fetidpmat_ctx->B_delta,MAT_FINAL_ASSEMBLY));
442 
443   BD1 = NULL;
444   BD2 = NULL;
445   if (fully_redundant) {
446     PetscCheck(!pcbddc->use_deluxe_scaling,comm,PETSC_ERR_SUP,"Deluxe FETIDP with fully-redundant multipliers to be implemented");
447     PetscCall(MatCreate(PETSC_COMM_SELF,&ScalingMat));
448     PetscCall(MatSetSizes(ScalingMat,n_local_lambda,n_local_lambda,n_local_lambda,n_local_lambda));
449     PetscCall(MatSetType(ScalingMat,MATSEQAIJ));
450     PetscCall(MatSeqAIJSetPreallocation(ScalingMat,1,NULL));
451     for (i=0;i<n_local_lambda;i++) {
452       PetscCall(MatSetValue(ScalingMat,i,i,scaling_factors[i],INSERT_VALUES));
453     }
454     PetscCall(MatAssemblyBegin(ScalingMat,MAT_FINAL_ASSEMBLY));
455     PetscCall(MatAssemblyEnd(ScalingMat,MAT_FINAL_ASSEMBLY));
456     PetscCall(MatMatMult(ScalingMat,fetidpmat_ctx->B_delta,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&fetidpmat_ctx->B_Ddelta));
457     PetscCall(MatDestroy(&ScalingMat));
458   } else {
459     PetscCall(MatCreate(PETSC_COMM_SELF,&fetidpmat_ctx->B_Ddelta));
460     PetscCall(MatSetSizes(fetidpmat_ctx->B_Ddelta,n_local_lambda,pcis->n_B,n_local_lambda,pcis->n_B));
461     if (!pcbddc->use_deluxe_scaling || !pcbddc->sub_schurs) {
462       PetscCall(MatSetType(fetidpmat_ctx->B_Ddelta,MATSEQAIJ));
463       PetscCall(MatSeqAIJSetPreallocation(fetidpmat_ctx->B_Ddelta,1,NULL));
464       for (i=0;i<n_local_lambda;i++) {
465         PetscCall(MatSetValue(fetidpmat_ctx->B_Ddelta,i,cols_B_delta[i],scaling_factors[i],INSERT_VALUES));
466       }
467       PetscCall(MatAssemblyBegin(fetidpmat_ctx->B_Ddelta,MAT_FINAL_ASSEMBLY));
468       PetscCall(MatAssemblyEnd(fetidpmat_ctx->B_Ddelta,MAT_FINAL_ASSEMBLY));
469     } else {
470       /* scaling as in Klawonn-Widlund 1999 */
471       PCBDDCDeluxeScaling deluxe_ctx = pcbddc->deluxe_ctx;
472       PCBDDCSubSchurs     sub_schurs = pcbddc->sub_schurs;
473       Mat                 T;
474       PetscScalar         *W,lwork,*Bwork;
475       const PetscInt      *idxs = NULL;
476       PetscInt            cum,mss,*nnz;
477       PetscBLASInt        *pivots,B_lwork,B_N,B_ierr;
478 
479       PetscCheck(pcbddc->deluxe_singlemat,comm,PETSC_ERR_USER,"Cannot compute B_Ddelta! rerun with -pc_bddc_deluxe_singlemat");
480       mss  = 0;
481       PetscCall(PetscCalloc1(pcis->n_B,&nnz));
482       if (sub_schurs->is_Ej_all) {
483         PetscCall(ISGetIndices(sub_schurs->is_Ej_all,&idxs));
484         for (i=0,cum=0;i<sub_schurs->n_subs;i++) {
485           PetscInt subset_size;
486 
487           PetscCall(ISGetLocalSize(sub_schurs->is_subs[i],&subset_size));
488           for (j=0;j<subset_size;j++) nnz[idxs[j+cum]] = subset_size;
489           mss  = PetscMax(mss,subset_size);
490           cum += subset_size;
491         }
492       }
493       PetscCall(MatCreate(PETSC_COMM_SELF,&T));
494       PetscCall(MatSetSizes(T,pcis->n_B,pcis->n_B,pcis->n_B,pcis->n_B));
495       PetscCall(MatSetType(T,MATSEQAIJ));
496       PetscCall(MatSeqAIJSetPreallocation(T,0,nnz));
497       PetscCall(PetscFree(nnz));
498 
499       /* workspace allocation */
500       B_lwork = 0;
501       if (mss) {
502         PetscScalar dummy = 1;
503 
504         B_lwork = -1;
505         PetscCall(PetscBLASIntCast(mss,&B_N));
506         PetscCall(PetscFPTrapPush(PETSC_FP_TRAP_OFF));
507         PetscCallBLAS("LAPACKgetri",LAPACKgetri_(&B_N,&dummy,&B_N,&B_N,&lwork,&B_lwork,&B_ierr));
508         PetscCall(PetscFPTrapPop());
509         PetscCheck(!B_ierr,PETSC_COMM_SELF,PETSC_ERR_LIB,"Error in query to GETRI Lapack routine %d",(int)B_ierr);
510         PetscCall(PetscBLASIntCast((PetscInt)PetscRealPart(lwork),&B_lwork));
511       }
512       PetscCall(PetscMalloc3(mss*mss,&W,mss,&pivots,B_lwork,&Bwork));
513 
514       for (i=0,cum=0;i<sub_schurs->n_subs;i++) {
515         const PetscScalar *M;
516         PetscInt          subset_size;
517 
518         PetscCall(ISGetLocalSize(sub_schurs->is_subs[i],&subset_size));
519         PetscCall(PetscBLASIntCast(subset_size,&B_N));
520         PetscCall(MatDenseGetArrayRead(deluxe_ctx->seq_mat[i],&M));
521         PetscCall(PetscArraycpy(W,M,subset_size*subset_size));
522         PetscCall(MatDenseRestoreArrayRead(deluxe_ctx->seq_mat[i],&M));
523         PetscCall(PetscFPTrapPush(PETSC_FP_TRAP_OFF));
524         PetscCallBLAS("LAPACKgetrf",LAPACKgetrf_(&B_N,&B_N,W,&B_N,pivots,&B_ierr));
525         PetscCheck(!B_ierr,PETSC_COMM_SELF,PETSC_ERR_LIB,"Error in GETRF Lapack routine %d",(int)B_ierr);
526         PetscCallBLAS("LAPACKgetri",LAPACKgetri_(&B_N,W,&B_N,pivots,Bwork,&B_lwork,&B_ierr));
527         PetscCheck(!B_ierr,PETSC_COMM_SELF,PETSC_ERR_LIB,"Error in GETRI Lapack routine %d",(int)B_ierr);
528         PetscCall(PetscFPTrapPop());
529         /* silent static analyzer */
530         PetscCheck(idxs,PETSC_COMM_SELF,PETSC_ERR_PLIB,"IDXS not present");
531         PetscCall(MatSetValues(T,subset_size,idxs+cum,subset_size,idxs+cum,W,INSERT_VALUES));
532         cum += subset_size;
533       }
534       PetscCall(MatAssemblyBegin(T,MAT_FINAL_ASSEMBLY));
535       PetscCall(MatAssemblyEnd(T,MAT_FINAL_ASSEMBLY));
536       PetscCall(MatMatTransposeMult(T,fetidpmat_ctx->B_delta,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&BD1));
537       PetscCall(MatMatMult(fetidpmat_ctx->B_delta,BD1,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&BD2));
538       PetscCall(MatDestroy(&T));
539       PetscCall(PetscFree3(W,pivots,Bwork));
540       if (sub_schurs->is_Ej_all) {
541         PetscCall(ISRestoreIndices(sub_schurs->is_Ej_all,&idxs));
542       }
543     }
544   }
545   PetscCall(PetscFree(scaling_factors));
546   PetscCall(PetscFree(cols_B_delta));
547 
548   /* Layout of multipliers */
549   PetscCall(PetscLayoutCreate(comm,&llay));
550   PetscCall(PetscLayoutSetBlockSize(llay,1));
551   PetscCall(PetscLayoutSetSize(llay,fetidpmat_ctx->n_lambda));
552   PetscCall(PetscLayoutSetUp(llay));
553   PetscCall(PetscLayoutGetLocalSize(llay,&fetidpmat_ctx->n));
554 
555   /* Local work vector of multipliers */
556   PetscCall(VecCreate(PETSC_COMM_SELF,&fetidpmat_ctx->lambda_local));
557   PetscCall(VecSetSizes(fetidpmat_ctx->lambda_local,n_local_lambda,n_local_lambda));
558   PetscCall(VecSetType(fetidpmat_ctx->lambda_local,VECSEQ));
559 
560   if (BD2) {
561     ISLocalToGlobalMapping l2g;
562     Mat                    T,TA,*pT;
563     IS                     is;
564     PetscInt               nl,N;
565     BDdelta_DN             ctx;
566 
567     PetscCall(PetscLayoutGetLocalSize(llay,&nl));
568     PetscCall(PetscLayoutGetSize(llay,&N));
569     PetscCall(MatCreate(comm,&T));
570     PetscCall(MatSetSizes(T,nl,nl,N,N));
571     PetscCall(MatSetType(T,MATIS));
572     PetscCall(ISLocalToGlobalMappingCreate(comm,1,n_local_lambda,l2g_indices,PETSC_COPY_VALUES,&l2g));
573     PetscCall(MatSetLocalToGlobalMapping(T,l2g,l2g));
574     PetscCall(ISLocalToGlobalMappingDestroy(&l2g));
575     PetscCall(MatISSetLocalMat(T,BD2));
576     PetscCall(MatAssemblyBegin(T,MAT_FINAL_ASSEMBLY));
577     PetscCall(MatAssemblyEnd(T,MAT_FINAL_ASSEMBLY));
578     PetscCall(MatDestroy(&BD2));
579     PetscCall(MatConvert(T,MATAIJ,MAT_INITIAL_MATRIX,&TA));
580     PetscCall(MatDestroy(&T));
581     PetscCall(ISCreateGeneral(comm,n_local_lambda,l2g_indices,PETSC_USE_POINTER,&is));
582     PetscCall(MatCreateSubMatrices(TA,1,&is,&is,MAT_INITIAL_MATRIX,&pT));
583     PetscCall(MatDestroy(&TA));
584     PetscCall(ISDestroy(&is));
585     BD2  = pT[0];
586     PetscCall(PetscFree(pT));
587 
588     /* B_Ddelta for non-redundant multipliers with deluxe scaling */
589     PetscCall(PetscNew(&ctx));
590     PetscCall(MatSetType(fetidpmat_ctx->B_Ddelta,MATSHELL));
591     PetscCall(MatShellSetContext(fetidpmat_ctx->B_Ddelta,ctx));
592     PetscCall(MatShellSetOperation(fetidpmat_ctx->B_Ddelta,MATOP_MULT,(void (*)(void))MatMult_BDdelta_deluxe_nonred));
593     PetscCall(MatShellSetOperation(fetidpmat_ctx->B_Ddelta,MATOP_MULT_TRANSPOSE,(void (*)(void))MatMultTranspose_BDdelta_deluxe_nonred));
594     PetscCall(MatShellSetOperation(fetidpmat_ctx->B_Ddelta,MATOP_DESTROY,(void (*)(void))MatDestroy_BDdelta_deluxe_nonred));
595     PetscCall(MatSetUp(fetidpmat_ctx->B_Ddelta));
596 
597     PetscCall(PetscObjectReference((PetscObject)BD1));
598     ctx->BD = BD1;
599     PetscCall(KSPCreate(PETSC_COMM_SELF,&ctx->kBD));
600     PetscCall(KSPSetOperators(ctx->kBD,BD2,BD2));
601     PetscCall(VecDuplicate(fetidpmat_ctx->lambda_local,&ctx->work));
602     fetidpmat_ctx->deluxe_nonred = PETSC_TRUE;
603   }
604   PetscCall(MatDestroy(&BD1));
605   PetscCall(MatDestroy(&BD2));
606 
607   /* fetidpmat sizes */
608   fetidpmat_ctx->n += nPgl;
609   fetidpmat_ctx->N  = fetidpmat_ctx->n_lambda+nPg;
610 
611   /* Global vector for FETI-DP linear system */
612   PetscCall(VecCreate(comm,&fetidp_global));
613   PetscCall(VecSetSizes(fetidp_global,fetidpmat_ctx->n,fetidpmat_ctx->N));
614   PetscCall(VecSetType(fetidp_global,VECMPI));
615   PetscCall(VecSetUp(fetidp_global));
616 
617   /* Decide layout for fetidp dofs: if it is a saddle point problem
618      pressure is ordered first in the local part of the global vector
619      of the FETI-DP linear system */
620   if (nPg) {
621     Vec            v;
622     IS             IS_l2g_p,ais;
623     PetscLayout    alay;
624     const PetscInt *idxs,*pranges,*aranges,*lranges;
625     PetscInt       *l2g_indices_p,rst;
626     PetscMPIInt    rank;
627 
628     PetscCall(PetscMalloc1(nPl,&l2g_indices_p));
629     PetscCall(VecGetLayout(fetidp_global,&alay));
630     PetscCall(PetscLayoutGetRanges(alay,&aranges));
631     PetscCall(PetscLayoutGetRanges(play,&pranges));
632     PetscCall(PetscLayoutGetRanges(llay,&lranges));
633 
634     PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)fetidp_global),&rank));
635     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)fetidp_global),pranges[rank+1]-pranges[rank],aranges[rank],1,&fetidpmat_ctx->pressure));
636     PetscCall(PetscObjectSetName((PetscObject)fetidpmat_ctx->pressure,"F_P"));
637     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)fetidp_global),lranges[rank+1]-lranges[rank],aranges[rank]+pranges[rank+1]-pranges[rank],1,&fetidpmat_ctx->lagrange));
638     PetscCall(PetscObjectSetName((PetscObject)fetidpmat_ctx->lagrange,"F_L"));
639     PetscCall(ISLocalToGlobalMappingGetIndices(l2gmap_p,&idxs));
640     /* shift local to global indices for pressure */
641     for (i=0;i<nPl;i++) {
642       PetscMPIInt owner;
643 
644       PetscCall(PetscLayoutFindOwner(play,idxs[i],&owner));
645       l2g_indices_p[i] = idxs[i]-pranges[owner]+aranges[owner];
646     }
647     PetscCall(ISLocalToGlobalMappingRestoreIndices(l2gmap_p,&idxs));
648     PetscCall(ISCreateGeneral(comm,nPl,l2g_indices_p,PETSC_OWN_POINTER,&IS_l2g_p));
649 
650     /* local to global scatter for pressure */
651     PetscCall(VecScatterCreate(fetidpmat_ctx->vP,NULL,fetidp_global,IS_l2g_p,&fetidpmat_ctx->l2g_p));
652     PetscCall(ISDestroy(&IS_l2g_p));
653 
654     /* scatter for lagrange multipliers only */
655     PetscCall(VecCreate(comm,&v));
656     PetscCall(VecSetType(v,VECSTANDARD));
657     PetscCall(VecSetLayout(v,llay));
658     PetscCall(VecSetUp(v));
659     PetscCall(ISCreateGeneral(comm,n_local_lambda,l2g_indices,PETSC_COPY_VALUES,&ais));
660     PetscCall(VecScatterCreate(fetidpmat_ctx->lambda_local,NULL,v,ais,&fetidpmat_ctx->l2g_lambda_only));
661     PetscCall(ISDestroy(&ais));
662     PetscCall(VecDestroy(&v));
663 
664     /* shift local to global indices for multipliers */
665     for (i=0;i<n_local_lambda;i++) {
666       PetscInt    ps;
667       PetscMPIInt owner;
668 
669       PetscCall(PetscLayoutFindOwner(llay,l2g_indices[i],&owner));
670       ps = pranges[owner+1]-pranges[owner];
671       l2g_indices[i] = l2g_indices[i]-lranges[owner]+aranges[owner]+ps;
672     }
673 
674     /* scatter from alldofs to pressures global fetidp vector */
675     PetscCall(PetscLayoutGetRange(alay,&rst,NULL));
676     PetscCall(ISCreateStride(comm,nPgl,rst,1,&ais));
677     PetscCall(VecScatterCreate(pcis->vec1_global,pP,fetidp_global,ais,&fetidpmat_ctx->g2g_p));
678     PetscCall(ISDestroy(&ais));
679   }
680   PetscCall(PetscLayoutDestroy(&llay));
681   PetscCall(PetscLayoutDestroy(&play));
682   PetscCall(ISCreateGeneral(comm,n_local_lambda,l2g_indices,PETSC_OWN_POINTER,&IS_l2g_lambda));
683 
684   /* scatter from local to global multipliers */
685   PetscCall(VecScatterCreate(fetidpmat_ctx->lambda_local,NULL,fetidp_global,IS_l2g_lambda,&fetidpmat_ctx->l2g_lambda));
686   PetscCall(ISDestroy(&IS_l2g_lambda));
687   PetscCall(ISLocalToGlobalMappingDestroy(&l2gmap_p));
688   PetscCall(VecDestroy(&fetidp_global));
689 
690   /* Create some work vectors needed by fetidp */
691   PetscCall(VecDuplicate(pcis->vec1_B,&fetidpmat_ctx->temp_solution_B));
692   PetscCall(VecDuplicate(pcis->vec1_D,&fetidpmat_ctx->temp_solution_D));
693   PetscFunctionReturn(0);
694 }
695 
696 PetscErrorCode PCBDDCSetupFETIDPPCContext(Mat fetimat, FETIDPPC_ctx fetidppc_ctx)
697 {
698   FETIDPMat_ctx  mat_ctx;
699   PC_BDDC        *pcbddc = (PC_BDDC*)fetidppc_ctx->pc->data;
700   PC_IS          *pcis = (PC_IS*)fetidppc_ctx->pc->data;
701   PetscBool      lumped = PETSC_FALSE;
702 
703   PetscFunctionBegin;
704   PetscCall(MatShellGetContext(fetimat,&mat_ctx));
705   /* get references from objects created when setting up feti mat context */
706   PetscCall(PetscObjectReference((PetscObject)mat_ctx->lambda_local));
707   fetidppc_ctx->lambda_local = mat_ctx->lambda_local;
708   PetscCall(PetscObjectReference((PetscObject)mat_ctx->B_Ddelta));
709   fetidppc_ctx->B_Ddelta = mat_ctx->B_Ddelta;
710   if (mat_ctx->deluxe_nonred) {
711     PC               pc,mpc;
712     BDdelta_DN       ctx;
713     MatSolverType    solver;
714     const char       *prefix;
715 
716     PetscCall(MatShellGetContext(mat_ctx->B_Ddelta,&ctx));
717     PetscCall(KSPSetType(ctx->kBD,KSPPREONLY));
718     PetscCall(KSPGetPC(ctx->kBD,&mpc));
719     PetscCall(KSPGetPC(pcbddc->ksp_D,&pc));
720     PetscCall(PCSetType(mpc,PCLU));
721     PetscCall(PCFactorGetMatSolverType(pc,(MatSolverType*)&solver));
722     if (solver) PetscCall(PCFactorSetMatSolverType(mpc,solver));
723     PetscCall(MatGetOptionsPrefix(fetimat,&prefix));
724     PetscCall(KSPSetOptionsPrefix(ctx->kBD,prefix));
725     PetscCall(KSPAppendOptionsPrefix(ctx->kBD,"bddelta_"));
726     PetscCall(KSPSetFromOptions(ctx->kBD));
727   }
728 
729   if (mat_ctx->l2g_lambda_only) {
730     PetscCall(PetscObjectReference((PetscObject)mat_ctx->l2g_lambda_only));
731     fetidppc_ctx->l2g_lambda = mat_ctx->l2g_lambda_only;
732   } else {
733     PetscCall(PetscObjectReference((PetscObject)mat_ctx->l2g_lambda));
734     fetidppc_ctx->l2g_lambda = mat_ctx->l2g_lambda;
735   }
736   /* Dirichlet preconditioner */
737   PetscCall(PetscOptionsGetBool(NULL,((PetscObject)fetimat)->prefix,"-pc_lumped",&lumped,NULL));
738   if (!lumped) {
739     IS        iV;
740     PetscBool discrete_harmonic = PETSC_FALSE;
741 
742     PetscCall(PetscObjectQuery((PetscObject)fetidppc_ctx->pc,"__KSPFETIDP_iV",(PetscObject*)&iV));
743     if (iV) {
744       PetscCall(PetscOptionsGetBool(NULL,((PetscObject)fetimat)->prefix,"-pc_discrete_harmonic",&discrete_harmonic,NULL));
745     }
746     if (discrete_harmonic) {
747       KSP             sksp;
748       PC              pc;
749       PCBDDCSubSchurs sub_schurs = pcbddc->sub_schurs;
750       Mat             A_II,A_IB,A_BI;
751       IS              iP = NULL;
752       PetscBool       isshell,reuse = PETSC_FALSE;
753       KSPType         ksptype;
754       const char      *prefix;
755 
756       /*
757         We constructs a Schur complement for
758 
759         | A_II A_ID |
760         | A_DI A_DD |
761 
762         instead of
763 
764         | A_II  B^t_II A_ID |
765         | B_II -C_II   B_ID |
766         | A_DI  B^t_ID A_DD |
767 
768       */
769       if (sub_schurs && sub_schurs->reuse_solver) {
770         PetscCall(PetscObjectQuery((PetscObject)sub_schurs->A,"__KSPFETIDP_iP",(PetscObject*)&iP));
771         if (iP) reuse = PETSC_TRUE;
772       }
773       if (!reuse) {
774         IS       aB;
775         PetscInt nb;
776         PetscCall(ISGetLocalSize(pcis->is_B_local,&nb));
777         PetscCall(ISCreateStride(PetscObjectComm((PetscObject)pcis->A_II),nb,0,1,&aB));
778         PetscCall(MatCreateSubMatrix(pcis->A_II,iV,iV,MAT_INITIAL_MATRIX,&A_II));
779         PetscCall(MatCreateSubMatrix(pcis->A_IB,iV,aB,MAT_INITIAL_MATRIX,&A_IB));
780         PetscCall(MatCreateSubMatrix(pcis->A_BI,aB,iV,MAT_INITIAL_MATRIX,&A_BI));
781         PetscCall(ISDestroy(&aB));
782       } else {
783         PetscCall(MatCreateSubMatrix(sub_schurs->A,pcis->is_I_local,pcis->is_B_local,MAT_INITIAL_MATRIX,&A_IB));
784         PetscCall(MatCreateSubMatrix(sub_schurs->A,pcis->is_B_local,pcis->is_I_local,MAT_INITIAL_MATRIX,&A_BI));
785         PetscCall(PetscObjectReference((PetscObject)pcis->A_II));
786         A_II = pcis->A_II;
787       }
788       PetscCall(MatCreateSchurComplement(A_II,A_II,A_IB,A_BI,pcis->A_BB,&fetidppc_ctx->S_j));
789 
790       /* propagate settings of solver */
791       PetscCall(MatSchurComplementGetKSP(fetidppc_ctx->S_j,&sksp));
792       PetscCall(KSPGetType(pcis->ksp_D,&ksptype));
793       PetscCall(KSPSetType(sksp,ksptype));
794       PetscCall(KSPGetPC(pcis->ksp_D,&pc));
795       PetscCall(PetscObjectTypeCompare((PetscObject)pc,PCSHELL,&isshell));
796       if (!isshell) {
797         MatSolverType    solver;
798         PCType           pctype;
799 
800         PetscCall(PCGetType(pc,&pctype));
801         PetscCall(PCFactorGetMatSolverType(pc,(MatSolverType*)&solver));
802         PetscCall(KSPGetPC(sksp,&pc));
803         PetscCall(PCSetType(pc,pctype));
804         if (solver) PetscCall(PCFactorSetMatSolverType(pc,solver));
805       } else {
806         PetscCall(KSPGetPC(sksp,&pc));
807         PetscCall(PCSetType(pc,PCLU));
808       }
809       PetscCall(MatDestroy(&A_II));
810       PetscCall(MatDestroy(&A_IB));
811       PetscCall(MatDestroy(&A_BI));
812       PetscCall(MatGetOptionsPrefix(fetimat,&prefix));
813       PetscCall(KSPSetOptionsPrefix(sksp,prefix));
814       PetscCall(KSPAppendOptionsPrefix(sksp,"harmonic_"));
815       PetscCall(KSPSetFromOptions(sksp));
816       if (reuse) {
817         PetscCall(KSPSetPC(sksp,sub_schurs->reuse_solver->interior_solver));
818         PetscCall(PetscObjectIncrementTabLevel((PetscObject)sub_schurs->reuse_solver->interior_solver,(PetscObject)sksp,0));
819       }
820     } else { /* default Dirichlet preconditioner is pde-harmonic */
821       PetscCall(MatCreateSchurComplement(pcis->A_II,pcis->A_II,pcis->A_IB,pcis->A_BI,pcis->A_BB,&fetidppc_ctx->S_j));
822       PetscCall(MatSchurComplementSetKSP(fetidppc_ctx->S_j,pcis->ksp_D));
823     }
824   } else {
825     PetscCall(PetscObjectReference((PetscObject)pcis->A_BB));
826     fetidppc_ctx->S_j = pcis->A_BB;
827   }
828   /* saddle-point */
829   if (mat_ctx->xPg) {
830     PetscCall(PetscObjectReference((PetscObject)mat_ctx->xPg));
831     fetidppc_ctx->xPg = mat_ctx->xPg;
832     PetscCall(PetscObjectReference((PetscObject)mat_ctx->yPg));
833     fetidppc_ctx->yPg = mat_ctx->yPg;
834   }
835   PetscFunctionReturn(0);
836 }
837 
838 PetscErrorCode FETIDPMatMult_Kernel(Mat fetimat, Vec x, Vec y, PetscBool trans)
839 {
840   FETIDPMat_ctx  mat_ctx;
841   PC_BDDC        *pcbddc;
842   PC_IS          *pcis;
843 
844   PetscFunctionBegin;
845   PetscCall(MatShellGetContext(fetimat,&mat_ctx));
846   pcis = (PC_IS*)mat_ctx->pc->data;
847   pcbddc = (PC_BDDC*)mat_ctx->pc->data;
848   /* Application of B_delta^T */
849   PetscCall(VecSet(pcis->vec1_B,0.));
850   PetscCall(VecScatterBegin(mat_ctx->l2g_lambda,x,mat_ctx->lambda_local,INSERT_VALUES,SCATTER_REVERSE));
851   PetscCall(VecScatterEnd(mat_ctx->l2g_lambda,x,mat_ctx->lambda_local,INSERT_VALUES,SCATTER_REVERSE));
852   PetscCall(MatMultTranspose(mat_ctx->B_delta,mat_ctx->lambda_local,pcis->vec1_B));
853 
854   /* Add contribution from saddle point */
855   if (mat_ctx->l2g_p) {
856     PetscCall(VecScatterBegin(mat_ctx->l2g_p,x,mat_ctx->vP,INSERT_VALUES,SCATTER_REVERSE));
857     PetscCall(VecScatterEnd(mat_ctx->l2g_p,x,mat_ctx->vP,INSERT_VALUES,SCATTER_REVERSE));
858     if (pcbddc->switch_static) {
859       if (trans) {
860         PetscCall(MatMultTranspose(mat_ctx->B_BI,mat_ctx->vP,pcis->vec1_D));
861       } else {
862         PetscCall(MatMult(mat_ctx->Bt_BI,mat_ctx->vP,pcis->vec1_D));
863       }
864     }
865     if (trans) {
866       PetscCall(MatMultTransposeAdd(mat_ctx->B_BB,mat_ctx->vP,pcis->vec1_B,pcis->vec1_B));
867     } else {
868       PetscCall(MatMultAdd(mat_ctx->Bt_BB,mat_ctx->vP,pcis->vec1_B,pcis->vec1_B));
869     }
870   } else {
871     if (pcbddc->switch_static) PetscCall(VecSet(pcis->vec1_D,0.0));
872   }
873   /* Application of \widetilde{S}^-1 */
874   PetscCall(PetscArrayzero(pcbddc->benign_p0,pcbddc->benign_n));
875   PetscCall(PCBDDCApplyInterfacePreconditioner(mat_ctx->pc,trans));
876   PetscCall(PetscArrayzero(pcbddc->benign_p0,pcbddc->benign_n));
877   PetscCall(VecSet(y,0.0));
878   /* Application of B_delta */
879   PetscCall(MatMult(mat_ctx->B_delta,pcis->vec1_B,mat_ctx->lambda_local));
880   /* Contribution from boundary pressures */
881   if (mat_ctx->C) {
882     const PetscScalar *lx;
883     PetscScalar       *ly;
884 
885     /* pressure ordered first in the local part of x and y */
886     PetscCall(VecGetArrayRead(x,&lx));
887     PetscCall(VecGetArray(y,&ly));
888     PetscCall(VecPlaceArray(mat_ctx->xPg,lx));
889     PetscCall(VecPlaceArray(mat_ctx->yPg,ly));
890     if (trans) {
891       PetscCall(MatMultTranspose(mat_ctx->C,mat_ctx->xPg,mat_ctx->yPg));
892     } else {
893       PetscCall(MatMult(mat_ctx->C,mat_ctx->xPg,mat_ctx->yPg));
894     }
895     PetscCall(VecResetArray(mat_ctx->xPg));
896     PetscCall(VecResetArray(mat_ctx->yPg));
897     PetscCall(VecRestoreArrayRead(x,&lx));
898     PetscCall(VecRestoreArray(y,&ly));
899   }
900   /* Add contribution from saddle point */
901   if (mat_ctx->l2g_p) {
902     if (trans) {
903       PetscCall(MatMultTranspose(mat_ctx->Bt_BB,pcis->vec1_B,mat_ctx->vP));
904     } else {
905       PetscCall(MatMult(mat_ctx->B_BB,pcis->vec1_B,mat_ctx->vP));
906     }
907     if (pcbddc->switch_static) {
908       if (trans) {
909         PetscCall(MatMultTransposeAdd(mat_ctx->Bt_BI,pcis->vec1_D,mat_ctx->vP,mat_ctx->vP));
910       } else {
911         PetscCall(MatMultAdd(mat_ctx->B_BI,pcis->vec1_D,mat_ctx->vP,mat_ctx->vP));
912       }
913     }
914     PetscCall(VecScatterBegin(mat_ctx->l2g_p,mat_ctx->vP,y,ADD_VALUES,SCATTER_FORWARD));
915     PetscCall(VecScatterEnd(mat_ctx->l2g_p,mat_ctx->vP,y,ADD_VALUES,SCATTER_FORWARD));
916   }
917   PetscCall(VecScatterBegin(mat_ctx->l2g_lambda,mat_ctx->lambda_local,y,ADD_VALUES,SCATTER_FORWARD));
918   PetscCall(VecScatterEnd(mat_ctx->l2g_lambda,mat_ctx->lambda_local,y,ADD_VALUES,SCATTER_FORWARD));
919   PetscFunctionReturn(0);
920 }
921 
922 PetscErrorCode FETIDPMatMult(Mat fetimat, Vec x, Vec y)
923 {
924   PetscFunctionBegin;
925   PetscCall(FETIDPMatMult_Kernel(fetimat,x,y,PETSC_FALSE));
926   PetscFunctionReturn(0);
927 }
928 
929 PetscErrorCode FETIDPMatMultTranspose(Mat fetimat, Vec x, Vec y)
930 {
931   PetscFunctionBegin;
932   PetscCall(FETIDPMatMult_Kernel(fetimat,x,y,PETSC_TRUE));
933   PetscFunctionReturn(0);
934 }
935 
936 PetscErrorCode FETIDPPCApply_Kernel(PC fetipc, Vec x, Vec y, PetscBool trans)
937 {
938   FETIDPPC_ctx   pc_ctx;
939   PC_IS          *pcis;
940 
941   PetscFunctionBegin;
942   PetscCall(PCShellGetContext(fetipc,&pc_ctx));
943   pcis = (PC_IS*)pc_ctx->pc->data;
944   /* Application of B_Ddelta^T */
945   PetscCall(VecScatterBegin(pc_ctx->l2g_lambda,x,pc_ctx->lambda_local,INSERT_VALUES,SCATTER_REVERSE));
946   PetscCall(VecScatterEnd(pc_ctx->l2g_lambda,x,pc_ctx->lambda_local,INSERT_VALUES,SCATTER_REVERSE));
947   PetscCall(VecSet(pcis->vec2_B,0.0));
948   PetscCall(MatMultTranspose(pc_ctx->B_Ddelta,pc_ctx->lambda_local,pcis->vec2_B));
949   /* Application of local Schur complement */
950   if (trans) {
951     PetscCall(MatMultTranspose(pc_ctx->S_j,pcis->vec2_B,pcis->vec1_B));
952   } else {
953     PetscCall(MatMult(pc_ctx->S_j,pcis->vec2_B,pcis->vec1_B));
954   }
955   /* Application of B_Ddelta */
956   PetscCall(MatMult(pc_ctx->B_Ddelta,pcis->vec1_B,pc_ctx->lambda_local));
957   PetscCall(VecSet(y,0.0));
958   PetscCall(VecScatterBegin(pc_ctx->l2g_lambda,pc_ctx->lambda_local,y,ADD_VALUES,SCATTER_FORWARD));
959   PetscCall(VecScatterEnd(pc_ctx->l2g_lambda,pc_ctx->lambda_local,y,ADD_VALUES,SCATTER_FORWARD));
960   PetscFunctionReturn(0);
961 }
962 
963 PetscErrorCode FETIDPPCApply(PC pc, Vec x, Vec y)
964 {
965   PetscFunctionBegin;
966   PetscCall(FETIDPPCApply_Kernel(pc,x,y,PETSC_FALSE));
967   PetscFunctionReturn(0);
968 }
969 
970 PetscErrorCode FETIDPPCApplyTranspose(PC pc, Vec x, Vec y)
971 {
972   PetscFunctionBegin;
973   PetscCall(FETIDPPCApply_Kernel(pc,x,y,PETSC_TRUE));
974   PetscFunctionReturn(0);
975 }
976 
977 PetscErrorCode FETIDPPCView(PC pc, PetscViewer viewer)
978 {
979   FETIDPPC_ctx      pc_ctx;
980   PetscBool         iascii;
981   PetscViewer       sviewer;
982 
983   PetscFunctionBegin;
984   PetscCall(PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii));
985   if (iascii) {
986     PetscMPIInt rank;
987     PetscBool   isschur,isshell;
988 
989     PetscCall(PCShellGetContext(pc,&pc_ctx));
990     PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)pc),&rank));
991     PetscCall(PetscObjectTypeCompare((PetscObject)pc_ctx->S_j,MATSCHURCOMPLEMENT,&isschur));
992     if (isschur) {
993       PetscCall(PetscViewerASCIIPrintf(viewer,"  Dirichlet preconditioner (just from rank 0)\n"));
994     } else {
995       PetscCall(PetscViewerASCIIPrintf(viewer,"  Lumped preconditioner (just from rank 0)\n"));
996     }
997     PetscCall(PetscViewerGetSubViewer(viewer,PetscObjectComm((PetscObject)pc_ctx->S_j),&sviewer));
998     if (rank == 0) {
999       PetscCall(PetscViewerPushFormat(sviewer,PETSC_VIEWER_ASCII_INFO));
1000       PetscCall(PetscViewerASCIIPushTab(sviewer));
1001       PetscCall(MatView(pc_ctx->S_j,sviewer));
1002       PetscCall(PetscViewerASCIIPopTab(sviewer));
1003       PetscCall(PetscViewerPopFormat(sviewer));
1004     }
1005     PetscCall(PetscViewerRestoreSubViewer(viewer,PetscObjectComm((PetscObject)pc_ctx->S_j),&sviewer));
1006     PetscCall(PetscObjectTypeCompare((PetscObject)pc_ctx->B_Ddelta,MATSHELL,&isshell));
1007     if (isshell) {
1008       BDdelta_DN ctx;
1009       PetscCall(PetscViewerASCIIPrintf(viewer,"  FETI-DP BDdelta: DB^t * (B D^-1 B^t)^-1 for deluxe scaling (just from rank 0)\n"));
1010       PetscCall(MatShellGetContext(pc_ctx->B_Ddelta,&ctx));
1011       PetscCall(PetscViewerGetSubViewer(viewer,PetscObjectComm((PetscObject)pc_ctx->S_j),&sviewer));
1012       if (rank == 0) {
1013         PetscInt tl;
1014 
1015         PetscCall(PetscViewerASCIIGetTab(sviewer,&tl));
1016         PetscCall(PetscObjectSetTabLevel((PetscObject)ctx->kBD,tl));
1017         PetscCall(KSPView(ctx->kBD,sviewer));
1018         PetscCall(PetscViewerPushFormat(sviewer,PETSC_VIEWER_ASCII_INFO));
1019         PetscCall(MatView(ctx->BD,sviewer));
1020         PetscCall(PetscViewerPopFormat(sviewer));
1021       }
1022       PetscCall(PetscViewerRestoreSubViewer(viewer,PetscObjectComm((PetscObject)pc_ctx->S_j),&sviewer));
1023     }
1024     PetscCall(PetscViewerFlush(viewer));
1025   }
1026   PetscFunctionReturn(0);
1027 }
1028