xref: /petsc/src/ksp/pc/impls/bddc/bddcfetidp.c (revision daa037dfd3c3bec8dc8659548d2b20b07c1dc6de)
1 #include <../src/ksp/pc/impls/bddc/bddc.h>
2 #include <../src/ksp/pc/impls/bddc/bddcprivate.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) {
216       PetscCall(PetscObjectReference((PetscObject)fetidpmat_ctx->rhs_flip));
217     }
218   }
219 
220   /* Default type of lagrange multipliers is non-redundant */
221   fully_redundant = fetidpmat_ctx->fully_redundant;
222 
223   /* Evaluate local and global number of lagrange multipliers */
224   PetscCall(VecSet(pcis->vec1_N,0.0));
225   n_local_lambda = 0;
226   partial_sum = 0;
227   n_boundary_dofs = 0;
228   s = 0;
229 
230   /* Get Vertices used to define the BDDC */
231   PetscCall(PCBDDCGraphGetCandidatesIS(pcbddc->mat_graph,NULL,NULL,NULL,NULL,&isvert));
232   PetscCall(ISGetLocalSize(isvert,&n_vertices));
233   PetscCall(ISGetIndices(isvert,&vertex_indices));
234 
235   dual_size = pcis->n_B-n_vertices;
236   PetscCall(PetscMalloc1(dual_size,&dual_dofs_boundary_indices));
237   PetscCall(PetscMalloc1(dual_size,&aux_local_numbering_1));
238   PetscCall(PetscMalloc1(dual_size,&aux_local_numbering_2));
239 
240   PetscCall(VecGetArray(pcis->vec1_N,&array));
241   for (i=0;i<pcis->n;i++) {
242     j = mat_graph->count[i]; /* RECALL: mat_graph->count[i] does not count myself */
243     if (j > 0) n_boundary_dofs++;
244     skip_node = PETSC_FALSE;
245     if (s < n_vertices && vertex_indices[s] == i) { /* it works for a sorted set of vertices */
246       skip_node = PETSC_TRUE;
247       s++;
248     }
249     if (j < 1) skip_node = PETSC_TRUE;
250     if (mat_graph->special_dof[i] == PCBDDCGRAPH_DIRICHLET_MARK) skip_node = PETSC_TRUE;
251     if (!skip_node) {
252       if (fully_redundant) {
253         /* fully redundant set of lagrange multipliers */
254         n_lambda_for_dof = (j*(j+1))/2;
255       } else {
256         n_lambda_for_dof = j;
257       }
258       n_local_lambda += j;
259       /* needed to evaluate global number of lagrange multipliers */
260       array[i]=(1.0*n_lambda_for_dof)/(j+1.0); /* already scaled for the next global sum */
261       /* store some data needed */
262       dual_dofs_boundary_indices[partial_sum] = n_boundary_dofs-1;
263       aux_local_numbering_1[partial_sum] = i;
264       aux_local_numbering_2[partial_sum] = n_lambda_for_dof;
265       partial_sum++;
266     }
267   }
268   PetscCall(VecRestoreArray(pcis->vec1_N,&array));
269   PetscCall(ISRestoreIndices(isvert,&vertex_indices));
270   PetscCall(PCBDDCGraphRestoreCandidatesIS(pcbddc->mat_graph,NULL,NULL,NULL,NULL,&isvert));
271   dual_size = partial_sum;
272 
273   /* compute global ordering of lagrange multipliers and associate l2g map */
274   PetscCall(ISCreateGeneral(comm,partial_sum,aux_local_numbering_1,PETSC_COPY_VALUES,&subset_n));
275   PetscCall(ISLocalToGlobalMappingApplyIS(pcis->mapping,subset_n,&subset));
276   PetscCall(ISDestroy(&subset_n));
277   PetscCall(ISCreateGeneral(comm,partial_sum,aux_local_numbering_2,PETSC_OWN_POINTER,&subset_mult));
278   PetscCall(ISRenumber(subset,subset_mult,&fetidpmat_ctx->n_lambda,&subset_n));
279   PetscCall(ISDestroy(&subset));
280 
281   if (PetscDefined(USE_DEBUG)) {
282     PetscCall(VecSet(pcis->vec1_global,0.0));
283     PetscCall(VecScatterBegin(matis->rctx,pcis->vec1_N,pcis->vec1_global,ADD_VALUES,SCATTER_REVERSE));
284     PetscCall(VecScatterEnd(matis->rctx,pcis->vec1_N,pcis->vec1_global,ADD_VALUES,SCATTER_REVERSE));
285     PetscCall(VecSum(pcis->vec1_global,&scalar_value));
286     i = (PetscInt)PetscRealPart(scalar_value);
287     PetscCheck(i == fetidpmat_ctx->n_lambda,PETSC_COMM_WORLD,PETSC_ERR_PLIB,"Global number of multipliers mismatch! (%D != %D)",fetidpmat_ctx->n_lambda,i);
288   }
289 
290   /* init data for scaling factors exchange */
291   if (!pcbddc->use_deluxe_scaling) {
292     PetscInt    *ptrs_buffer,neigh_position;
293     PetscScalar *send_buffer,*recv_buffer;
294     MPI_Request *send_reqs,*recv_reqs;
295 
296     partial_sum = 0;
297     PetscCall(PetscMalloc1(pcis->n_neigh,&ptrs_buffer));
298     PetscCall(PetscMalloc1(PetscMax(pcis->n_neigh-1,0),&send_reqs));
299     PetscCall(PetscMalloc1(PetscMax(pcis->n_neigh-1,0),&recv_reqs));
300     PetscCall(PetscMalloc1(pcis->n+1,&all_factors));
301     if (pcis->n_neigh > 0) ptrs_buffer[0]=0;
302     for (i=1;i<pcis->n_neigh;i++) {
303       partial_sum += pcis->n_shared[i];
304       ptrs_buffer[i] = ptrs_buffer[i-1]+pcis->n_shared[i];
305     }
306     PetscCall(PetscMalloc1(partial_sum,&send_buffer));
307     PetscCall(PetscMalloc1(partial_sum,&recv_buffer));
308     PetscCall(PetscMalloc1(partial_sum,&all_factors[0]));
309     for (i=0;i<pcis->n-1;i++) {
310       j = mat_graph->count[i];
311       all_factors[i+1]=all_factors[i]+j;
312     }
313 
314     /* scatter B scaling to N vec */
315     PetscCall(VecScatterBegin(pcis->N_to_B,pcis->D,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE));
316     PetscCall(VecScatterEnd(pcis->N_to_B,pcis->D,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE));
317     /* communications */
318     PetscCall(VecGetArrayRead(pcis->vec1_N,(const PetscScalar**)&array));
319     for (i=1;i<pcis->n_neigh;i++) {
320       for (j=0;j<pcis->n_shared[i];j++) {
321         send_buffer[ptrs_buffer[i-1]+j]=array[pcis->shared[i][j]];
322       }
323       PetscCall(PetscMPIIntCast(ptrs_buffer[i]-ptrs_buffer[i-1],&buf_size));
324       PetscCall(PetscMPIIntCast(pcis->neigh[i],&neigh));
325       PetscCallMPI(MPI_Isend(&send_buffer[ptrs_buffer[i-1]],buf_size,MPIU_SCALAR,neigh,0,comm,&send_reqs[i-1]));
326       PetscCallMPI(MPI_Irecv(&recv_buffer[ptrs_buffer[i-1]],buf_size,MPIU_SCALAR,neigh,0,comm,&recv_reqs[i-1]));
327     }
328     PetscCall(VecRestoreArrayRead(pcis->vec1_N,(const PetscScalar**)&array));
329     if (pcis->n_neigh > 0) {
330       PetscCallMPI(MPI_Waitall(pcis->n_neigh-1,recv_reqs,MPI_STATUSES_IGNORE));
331     }
332     /* put values in correct places */
333     for (i=1;i<pcis->n_neigh;i++) {
334       for (j=0;j<pcis->n_shared[i];j++) {
335         k = pcis->shared[i][j];
336         neigh_position = 0;
337         while (mat_graph->neighbours_set[k][neigh_position] != pcis->neigh[i]) {neigh_position++;}
338         all_factors[k][neigh_position]=recv_buffer[ptrs_buffer[i-1]+j];
339       }
340     }
341     if (pcis->n_neigh > 0) {
342       PetscCallMPI(MPI_Waitall(pcis->n_neigh-1,send_reqs,MPI_STATUSES_IGNORE));
343     }
344     PetscCall(PetscFree(send_reqs));
345     PetscCall(PetscFree(recv_reqs));
346     PetscCall(PetscFree(send_buffer));
347     PetscCall(PetscFree(recv_buffer));
348     PetscCall(PetscFree(ptrs_buffer));
349   }
350 
351   /* Compute B and B_delta (local actions) */
352   PetscCall(PetscMalloc1(pcis->n_neigh,&aux_sums));
353   PetscCall(PetscMalloc1(n_local_lambda,&l2g_indices));
354   PetscCall(PetscMalloc1(n_local_lambda,&vals_B_delta));
355   PetscCall(PetscMalloc1(n_local_lambda,&cols_B_delta));
356   if (!pcbddc->use_deluxe_scaling) {
357     PetscCall(PetscMalloc1(n_local_lambda,&scaling_factors));
358   } else {
359     scaling_factors = NULL;
360     all_factors     = NULL;
361   }
362   PetscCall(ISGetIndices(subset_n,&aux_global_numbering));
363   partial_sum=0;
364   cum = 0;
365   for (i=0;i<dual_size;i++) {
366     n_global_lambda = aux_global_numbering[cum];
367     j = mat_graph->count[aux_local_numbering_1[i]];
368     aux_sums[0]=0;
369     for (s=1;s<j;s++) {
370       aux_sums[s]=aux_sums[s-1]+j-s+1;
371     }
372     if (all_factors) array = all_factors[aux_local_numbering_1[i]];
373     n_neg_values = 0;
374     while (n_neg_values < j && mat_graph->neighbours_set[aux_local_numbering_1[i]][n_neg_values] < rank) {n_neg_values++;}
375     n_pos_values = j - n_neg_values;
376     if (fully_redundant) {
377       for (s=0;s<n_neg_values;s++) {
378         l2g_indices    [partial_sum+s]=aux_sums[s]+n_neg_values-s-1+n_global_lambda;
379         cols_B_delta   [partial_sum+s]=dual_dofs_boundary_indices[i];
380         vals_B_delta   [partial_sum+s]=-1.0;
381         if (!pcbddc->use_deluxe_scaling) scaling_factors[partial_sum+s]=array[s];
382       }
383       for (s=0;s<n_pos_values;s++) {
384         l2g_indices    [partial_sum+s+n_neg_values]=aux_sums[n_neg_values]+s+n_global_lambda;
385         cols_B_delta   [partial_sum+s+n_neg_values]=dual_dofs_boundary_indices[i];
386         vals_B_delta   [partial_sum+s+n_neg_values]=1.0;
387         if (!pcbddc->use_deluxe_scaling) scaling_factors[partial_sum+s+n_neg_values]=array[s+n_neg_values];
388       }
389       partial_sum += j;
390     } else {
391       /* l2g_indices and default cols and vals of B_delta */
392       for (s=0;s<j;s++) {
393         l2g_indices    [partial_sum+s]=n_global_lambda+s;
394         cols_B_delta   [partial_sum+s]=dual_dofs_boundary_indices[i];
395         vals_B_delta   [partial_sum+s]=0.0;
396       }
397       /* B_delta */
398       if (n_neg_values > 0) { /* there's a rank next to me to the left */
399         vals_B_delta   [partial_sum+n_neg_values-1]=-1.0;
400       }
401       if (n_neg_values < j) { /* there's a rank next to me to the right */
402         vals_B_delta   [partial_sum+n_neg_values]=1.0;
403       }
404       /* scaling as in Klawonn-Widlund 1999 */
405       if (!pcbddc->use_deluxe_scaling) {
406         for (s=0;s<n_neg_values;s++) {
407           scalar_value = 0.0;
408           for (k=0;k<s+1;k++) scalar_value += array[k];
409           scaling_factors[partial_sum+s] = -scalar_value;
410         }
411         for (s=0;s<n_pos_values;s++) {
412           scalar_value = 0.0;
413           for (k=s+n_neg_values;k<j;k++) scalar_value += array[k];
414           scaling_factors[partial_sum+s+n_neg_values] = scalar_value;
415         }
416       }
417       partial_sum += j;
418     }
419     cum += aux_local_numbering_2[i];
420   }
421   PetscCall(ISRestoreIndices(subset_n,&aux_global_numbering));
422   PetscCall(ISDestroy(&subset_mult));
423   PetscCall(ISDestroy(&subset_n));
424   PetscCall(PetscFree(aux_sums));
425   PetscCall(PetscFree(aux_local_numbering_1));
426   PetscCall(PetscFree(dual_dofs_boundary_indices));
427   if (all_factors) {
428     PetscCall(PetscFree(all_factors[0]));
429     PetscCall(PetscFree(all_factors));
430   }
431 
432   /* Create local part of B_delta */
433   PetscCall(MatCreate(PETSC_COMM_SELF,&fetidpmat_ctx->B_delta));
434   PetscCall(MatSetSizes(fetidpmat_ctx->B_delta,n_local_lambda,pcis->n_B,n_local_lambda,pcis->n_B));
435   PetscCall(MatSetType(fetidpmat_ctx->B_delta,MATSEQAIJ));
436   PetscCall(MatSeqAIJSetPreallocation(fetidpmat_ctx->B_delta,1,NULL));
437   PetscCall(MatSetOption(fetidpmat_ctx->B_delta,MAT_IGNORE_ZERO_ENTRIES,PETSC_TRUE));
438   for (i=0;i<n_local_lambda;i++) {
439     PetscCall(MatSetValue(fetidpmat_ctx->B_delta,i,cols_B_delta[i],vals_B_delta[i],INSERT_VALUES));
440   }
441   PetscCall(PetscFree(vals_B_delta));
442   PetscCall(MatAssemblyBegin(fetidpmat_ctx->B_delta,MAT_FINAL_ASSEMBLY));
443   PetscCall(MatAssemblyEnd(fetidpmat_ctx->B_delta,MAT_FINAL_ASSEMBLY));
444 
445   BD1 = NULL;
446   BD2 = NULL;
447   if (fully_redundant) {
448     PetscCheck(!pcbddc->use_deluxe_scaling,comm,PETSC_ERR_SUP,"Deluxe FETIDP with fully-redundant multipliers to be implemented");
449     PetscCall(MatCreate(PETSC_COMM_SELF,&ScalingMat));
450     PetscCall(MatSetSizes(ScalingMat,n_local_lambda,n_local_lambda,n_local_lambda,n_local_lambda));
451     PetscCall(MatSetType(ScalingMat,MATSEQAIJ));
452     PetscCall(MatSeqAIJSetPreallocation(ScalingMat,1,NULL));
453     for (i=0;i<n_local_lambda;i++) {
454       PetscCall(MatSetValue(ScalingMat,i,i,scaling_factors[i],INSERT_VALUES));
455     }
456     PetscCall(MatAssemblyBegin(ScalingMat,MAT_FINAL_ASSEMBLY));
457     PetscCall(MatAssemblyEnd(ScalingMat,MAT_FINAL_ASSEMBLY));
458     PetscCall(MatMatMult(ScalingMat,fetidpmat_ctx->B_delta,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&fetidpmat_ctx->B_Ddelta));
459     PetscCall(MatDestroy(&ScalingMat));
460   } else {
461     PetscCall(MatCreate(PETSC_COMM_SELF,&fetidpmat_ctx->B_Ddelta));
462     PetscCall(MatSetSizes(fetidpmat_ctx->B_Ddelta,n_local_lambda,pcis->n_B,n_local_lambda,pcis->n_B));
463     if (!pcbddc->use_deluxe_scaling || !pcbddc->sub_schurs) {
464       PetscCall(MatSetType(fetidpmat_ctx->B_Ddelta,MATSEQAIJ));
465       PetscCall(MatSeqAIJSetPreallocation(fetidpmat_ctx->B_Ddelta,1,NULL));
466       for (i=0;i<n_local_lambda;i++) {
467         PetscCall(MatSetValue(fetidpmat_ctx->B_Ddelta,i,cols_B_delta[i],scaling_factors[i],INSERT_VALUES));
468       }
469       PetscCall(MatAssemblyBegin(fetidpmat_ctx->B_Ddelta,MAT_FINAL_ASSEMBLY));
470       PetscCall(MatAssemblyEnd(fetidpmat_ctx->B_Ddelta,MAT_FINAL_ASSEMBLY));
471     } else {
472       /* scaling as in Klawonn-Widlund 1999 */
473       PCBDDCDeluxeScaling deluxe_ctx = pcbddc->deluxe_ctx;
474       PCBDDCSubSchurs     sub_schurs = pcbddc->sub_schurs;
475       Mat                 T;
476       PetscScalar         *W,lwork,*Bwork;
477       const PetscInt      *idxs = NULL;
478       PetscInt            cum,mss,*nnz;
479       PetscBLASInt        *pivots,B_lwork,B_N,B_ierr;
480 
481       PetscCheck(pcbddc->deluxe_singlemat,comm,PETSC_ERR_USER,"Cannot compute B_Ddelta! rerun with -pc_bddc_deluxe_singlemat");
482       mss  = 0;
483       PetscCall(PetscCalloc1(pcis->n_B,&nnz));
484       if (sub_schurs->is_Ej_all) {
485         PetscCall(ISGetIndices(sub_schurs->is_Ej_all,&idxs));
486         for (i=0,cum=0;i<sub_schurs->n_subs;i++) {
487           PetscInt subset_size;
488 
489           PetscCall(ISGetLocalSize(sub_schurs->is_subs[i],&subset_size));
490           for (j=0;j<subset_size;j++) nnz[idxs[j+cum]] = subset_size;
491           mss  = PetscMax(mss,subset_size);
492           cum += subset_size;
493         }
494       }
495       PetscCall(MatCreate(PETSC_COMM_SELF,&T));
496       PetscCall(MatSetSizes(T,pcis->n_B,pcis->n_B,pcis->n_B,pcis->n_B));
497       PetscCall(MatSetType(T,MATSEQAIJ));
498       PetscCall(MatSeqAIJSetPreallocation(T,0,nnz));
499       PetscCall(PetscFree(nnz));
500 
501       /* workspace allocation */
502       B_lwork = 0;
503       if (mss) {
504         PetscScalar dummy = 1;
505 
506         B_lwork = -1;
507         PetscCall(PetscBLASIntCast(mss,&B_N));
508         PetscCall(PetscFPTrapPush(PETSC_FP_TRAP_OFF));
509         PetscStackCallBLAS("LAPACKgetri",LAPACKgetri_(&B_N,&dummy,&B_N,&B_N,&lwork,&B_lwork,&B_ierr));
510         PetscCall(PetscFPTrapPop());
511         PetscCheck(!B_ierr,PETSC_COMM_SELF,PETSC_ERR_LIB,"Error in query to GETRI Lapack routine %d",(int)B_ierr);
512         PetscCall(PetscBLASIntCast((PetscInt)PetscRealPart(lwork),&B_lwork));
513       }
514       PetscCall(PetscMalloc3(mss*mss,&W,mss,&pivots,B_lwork,&Bwork));
515 
516       for (i=0,cum=0;i<sub_schurs->n_subs;i++) {
517         const PetscScalar *M;
518         PetscInt          subset_size;
519 
520         PetscCall(ISGetLocalSize(sub_schurs->is_subs[i],&subset_size));
521         PetscCall(PetscBLASIntCast(subset_size,&B_N));
522         PetscCall(MatDenseGetArrayRead(deluxe_ctx->seq_mat[i],&M));
523         PetscCall(PetscArraycpy(W,M,subset_size*subset_size));
524         PetscCall(MatDenseRestoreArrayRead(deluxe_ctx->seq_mat[i],&M));
525         PetscCall(PetscFPTrapPush(PETSC_FP_TRAP_OFF));
526         PetscStackCallBLAS("LAPACKgetrf",LAPACKgetrf_(&B_N,&B_N,W,&B_N,pivots,&B_ierr));
527         PetscCheck(!B_ierr,PETSC_COMM_SELF,PETSC_ERR_LIB,"Error in GETRF Lapack routine %d",(int)B_ierr);
528         PetscStackCallBLAS("LAPACKgetri",LAPACKgetri_(&B_N,W,&B_N,pivots,Bwork,&B_lwork,&B_ierr));
529         PetscCheck(!B_ierr,PETSC_COMM_SELF,PETSC_ERR_LIB,"Error in GETRI Lapack routine %d",(int)B_ierr);
530         PetscCall(PetscFPTrapPop());
531         /* silent static analyzer */
532         PetscCheck(idxs,PETSC_COMM_SELF,PETSC_ERR_PLIB,"IDXS not present");
533         PetscCall(MatSetValues(T,subset_size,idxs+cum,subset_size,idxs+cum,W,INSERT_VALUES));
534         cum += subset_size;
535       }
536       PetscCall(MatAssemblyBegin(T,MAT_FINAL_ASSEMBLY));
537       PetscCall(MatAssemblyEnd(T,MAT_FINAL_ASSEMBLY));
538       PetscCall(MatMatTransposeMult(T,fetidpmat_ctx->B_delta,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&BD1));
539       PetscCall(MatMatMult(fetidpmat_ctx->B_delta,BD1,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&BD2));
540       PetscCall(MatDestroy(&T));
541       PetscCall(PetscFree3(W,pivots,Bwork));
542       if (sub_schurs->is_Ej_all) {
543         PetscCall(ISRestoreIndices(sub_schurs->is_Ej_all,&idxs));
544       }
545     }
546   }
547   PetscCall(PetscFree(scaling_factors));
548   PetscCall(PetscFree(cols_B_delta));
549 
550   /* Layout of multipliers */
551   PetscCall(PetscLayoutCreate(comm,&llay));
552   PetscCall(PetscLayoutSetBlockSize(llay,1));
553   PetscCall(PetscLayoutSetSize(llay,fetidpmat_ctx->n_lambda));
554   PetscCall(PetscLayoutSetUp(llay));
555   PetscCall(PetscLayoutGetLocalSize(llay,&fetidpmat_ctx->n));
556 
557   /* Local work vector of multipliers */
558   PetscCall(VecCreate(PETSC_COMM_SELF,&fetidpmat_ctx->lambda_local));
559   PetscCall(VecSetSizes(fetidpmat_ctx->lambda_local,n_local_lambda,n_local_lambda));
560   PetscCall(VecSetType(fetidpmat_ctx->lambda_local,VECSEQ));
561 
562   if (BD2) {
563     ISLocalToGlobalMapping l2g;
564     Mat                    T,TA,*pT;
565     IS                     is;
566     PetscInt               nl,N;
567     BDdelta_DN             ctx;
568 
569     PetscCall(PetscLayoutGetLocalSize(llay,&nl));
570     PetscCall(PetscLayoutGetSize(llay,&N));
571     PetscCall(MatCreate(comm,&T));
572     PetscCall(MatSetSizes(T,nl,nl,N,N));
573     PetscCall(MatSetType(T,MATIS));
574     PetscCall(ISLocalToGlobalMappingCreate(comm,1,n_local_lambda,l2g_indices,PETSC_COPY_VALUES,&l2g));
575     PetscCall(MatSetLocalToGlobalMapping(T,l2g,l2g));
576     PetscCall(ISLocalToGlobalMappingDestroy(&l2g));
577     PetscCall(MatISSetLocalMat(T,BD2));
578     PetscCall(MatAssemblyBegin(T,MAT_FINAL_ASSEMBLY));
579     PetscCall(MatAssemblyEnd(T,MAT_FINAL_ASSEMBLY));
580     PetscCall(MatDestroy(&BD2));
581     PetscCall(MatConvert(T,MATAIJ,MAT_INITIAL_MATRIX,&TA));
582     PetscCall(MatDestroy(&T));
583     PetscCall(ISCreateGeneral(comm,n_local_lambda,l2g_indices,PETSC_USE_POINTER,&is));
584     PetscCall(MatCreateSubMatrices(TA,1,&is,&is,MAT_INITIAL_MATRIX,&pT));
585     PetscCall(MatDestroy(&TA));
586     PetscCall(ISDestroy(&is));
587     BD2  = pT[0];
588     PetscCall(PetscFree(pT));
589 
590     /* B_Ddelta for non-redundant multipliers with deluxe scaling */
591     PetscCall(PetscNew(&ctx));
592     PetscCall(MatSetType(fetidpmat_ctx->B_Ddelta,MATSHELL));
593     PetscCall(MatShellSetContext(fetidpmat_ctx->B_Ddelta,ctx));
594     PetscCall(MatShellSetOperation(fetidpmat_ctx->B_Ddelta,MATOP_MULT,(void (*)(void))MatMult_BDdelta_deluxe_nonred));
595     PetscCall(MatShellSetOperation(fetidpmat_ctx->B_Ddelta,MATOP_MULT_TRANSPOSE,(void (*)(void))MatMultTranspose_BDdelta_deluxe_nonred));
596     PetscCall(MatShellSetOperation(fetidpmat_ctx->B_Ddelta,MATOP_DESTROY,(void (*)(void))MatDestroy_BDdelta_deluxe_nonred));
597     PetscCall(MatSetUp(fetidpmat_ctx->B_Ddelta));
598 
599     PetscCall(PetscObjectReference((PetscObject)BD1));
600     ctx->BD = BD1;
601     PetscCall(KSPCreate(PETSC_COMM_SELF,&ctx->kBD));
602     PetscCall(KSPSetOperators(ctx->kBD,BD2,BD2));
603     PetscCall(VecDuplicate(fetidpmat_ctx->lambda_local,&ctx->work));
604     fetidpmat_ctx->deluxe_nonred = PETSC_TRUE;
605   }
606   PetscCall(MatDestroy(&BD1));
607   PetscCall(MatDestroy(&BD2));
608 
609   /* fetidpmat sizes */
610   fetidpmat_ctx->n += nPgl;
611   fetidpmat_ctx->N  = fetidpmat_ctx->n_lambda+nPg;
612 
613   /* Global vector for FETI-DP linear system */
614   PetscCall(VecCreate(comm,&fetidp_global));
615   PetscCall(VecSetSizes(fetidp_global,fetidpmat_ctx->n,fetidpmat_ctx->N));
616   PetscCall(VecSetType(fetidp_global,VECMPI));
617   PetscCall(VecSetUp(fetidp_global));
618 
619   /* Decide layout for fetidp dofs: if it is a saddle point problem
620      pressure is ordered first in the local part of the global vector
621      of the FETI-DP linear system */
622   if (nPg) {
623     Vec            v;
624     IS             IS_l2g_p,ais;
625     PetscLayout    alay;
626     const PetscInt *idxs,*pranges,*aranges,*lranges;
627     PetscInt       *l2g_indices_p,rst;
628     PetscMPIInt    rank;
629 
630     PetscCall(PetscMalloc1(nPl,&l2g_indices_p));
631     PetscCall(VecGetLayout(fetidp_global,&alay));
632     PetscCall(PetscLayoutGetRanges(alay,&aranges));
633     PetscCall(PetscLayoutGetRanges(play,&pranges));
634     PetscCall(PetscLayoutGetRanges(llay,&lranges));
635 
636     PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)fetidp_global),&rank));
637     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)fetidp_global),pranges[rank+1]-pranges[rank],aranges[rank],1,&fetidpmat_ctx->pressure));
638     PetscCall(PetscObjectSetName((PetscObject)fetidpmat_ctx->pressure,"F_P"));
639     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)fetidp_global),lranges[rank+1]-lranges[rank],aranges[rank]+pranges[rank+1]-pranges[rank],1,&fetidpmat_ctx->lagrange));
640     PetscCall(PetscObjectSetName((PetscObject)fetidpmat_ctx->lagrange,"F_L"));
641     PetscCall(ISLocalToGlobalMappingGetIndices(l2gmap_p,&idxs));
642     /* shift local to global indices for pressure */
643     for (i=0;i<nPl;i++) {
644       PetscMPIInt owner;
645 
646       PetscCall(PetscLayoutFindOwner(play,idxs[i],&owner));
647       l2g_indices_p[i] = idxs[i]-pranges[owner]+aranges[owner];
648     }
649     PetscCall(ISLocalToGlobalMappingRestoreIndices(l2gmap_p,&idxs));
650     PetscCall(ISCreateGeneral(comm,nPl,l2g_indices_p,PETSC_OWN_POINTER,&IS_l2g_p));
651 
652     /* local to global scatter for pressure */
653     PetscCall(VecScatterCreate(fetidpmat_ctx->vP,NULL,fetidp_global,IS_l2g_p,&fetidpmat_ctx->l2g_p));
654     PetscCall(ISDestroy(&IS_l2g_p));
655 
656     /* scatter for lagrange multipliers only */
657     PetscCall(VecCreate(comm,&v));
658     PetscCall(VecSetType(v,VECSTANDARD));
659     PetscCall(VecSetLayout(v,llay));
660     PetscCall(VecSetUp(v));
661     PetscCall(ISCreateGeneral(comm,n_local_lambda,l2g_indices,PETSC_COPY_VALUES,&ais));
662     PetscCall(VecScatterCreate(fetidpmat_ctx->lambda_local,NULL,v,ais,&fetidpmat_ctx->l2g_lambda_only));
663     PetscCall(ISDestroy(&ais));
664     PetscCall(VecDestroy(&v));
665 
666     /* shift local to global indices for multipliers */
667     for (i=0;i<n_local_lambda;i++) {
668       PetscInt    ps;
669       PetscMPIInt owner;
670 
671       PetscCall(PetscLayoutFindOwner(llay,l2g_indices[i],&owner));
672       ps = pranges[owner+1]-pranges[owner];
673       l2g_indices[i] = l2g_indices[i]-lranges[owner]+aranges[owner]+ps;
674     }
675 
676     /* scatter from alldofs to pressures global fetidp vector */
677     PetscCall(PetscLayoutGetRange(alay,&rst,NULL));
678     PetscCall(ISCreateStride(comm,nPgl,rst,1,&ais));
679     PetscCall(VecScatterCreate(pcis->vec1_global,pP,fetidp_global,ais,&fetidpmat_ctx->g2g_p));
680     PetscCall(ISDestroy(&ais));
681   }
682   PetscCall(PetscLayoutDestroy(&llay));
683   PetscCall(PetscLayoutDestroy(&play));
684   PetscCall(ISCreateGeneral(comm,n_local_lambda,l2g_indices,PETSC_OWN_POINTER,&IS_l2g_lambda));
685 
686   /* scatter from local to global multipliers */
687   PetscCall(VecScatterCreate(fetidpmat_ctx->lambda_local,NULL,fetidp_global,IS_l2g_lambda,&fetidpmat_ctx->l2g_lambda));
688   PetscCall(ISDestroy(&IS_l2g_lambda));
689   PetscCall(ISLocalToGlobalMappingDestroy(&l2gmap_p));
690   PetscCall(VecDestroy(&fetidp_global));
691 
692   /* Create some work vectors needed by fetidp */
693   PetscCall(VecDuplicate(pcis->vec1_B,&fetidpmat_ctx->temp_solution_B));
694   PetscCall(VecDuplicate(pcis->vec1_D,&fetidpmat_ctx->temp_solution_D));
695   PetscFunctionReturn(0);
696 }
697 
698 PetscErrorCode PCBDDCSetupFETIDPPCContext(Mat fetimat, FETIDPPC_ctx fetidppc_ctx)
699 {
700   FETIDPMat_ctx  mat_ctx;
701   PC_BDDC        *pcbddc = (PC_BDDC*)fetidppc_ctx->pc->data;
702   PC_IS          *pcis = (PC_IS*)fetidppc_ctx->pc->data;
703   PetscBool      lumped = PETSC_FALSE;
704 
705   PetscFunctionBegin;
706   PetscCall(MatShellGetContext(fetimat,&mat_ctx));
707   /* get references from objects created when setting up feti mat context */
708   PetscCall(PetscObjectReference((PetscObject)mat_ctx->lambda_local));
709   fetidppc_ctx->lambda_local = mat_ctx->lambda_local;
710   PetscCall(PetscObjectReference((PetscObject)mat_ctx->B_Ddelta));
711   fetidppc_ctx->B_Ddelta = mat_ctx->B_Ddelta;
712   if (mat_ctx->deluxe_nonred) {
713     PC               pc,mpc;
714     BDdelta_DN       ctx;
715     MatSolverType    solver;
716     const char       *prefix;
717 
718     PetscCall(MatShellGetContext(mat_ctx->B_Ddelta,&ctx));
719     PetscCall(KSPSetType(ctx->kBD,KSPPREONLY));
720     PetscCall(KSPGetPC(ctx->kBD,&mpc));
721     PetscCall(KSPGetPC(pcbddc->ksp_D,&pc));
722     PetscCall(PCSetType(mpc,PCLU));
723     PetscCall(PCFactorGetMatSolverType(pc,(MatSolverType*)&solver));
724     if (solver) {
725       PetscCall(PCFactorSetMatSolverType(mpc,solver));
726     }
727     PetscCall(MatGetOptionsPrefix(fetimat,&prefix));
728     PetscCall(KSPSetOptionsPrefix(ctx->kBD,prefix));
729     PetscCall(KSPAppendOptionsPrefix(ctx->kBD,"bddelta_"));
730     PetscCall(KSPSetFromOptions(ctx->kBD));
731   }
732 
733   if (mat_ctx->l2g_lambda_only) {
734     PetscCall(PetscObjectReference((PetscObject)mat_ctx->l2g_lambda_only));
735     fetidppc_ctx->l2g_lambda = mat_ctx->l2g_lambda_only;
736   } else {
737     PetscCall(PetscObjectReference((PetscObject)mat_ctx->l2g_lambda));
738     fetidppc_ctx->l2g_lambda = mat_ctx->l2g_lambda;
739   }
740   /* Dirichlet preconditioner */
741   PetscCall(PetscOptionsGetBool(NULL,((PetscObject)fetimat)->prefix,"-pc_lumped",&lumped,NULL));
742   if (!lumped) {
743     IS        iV;
744     PetscBool discrete_harmonic = PETSC_FALSE;
745 
746     PetscCall(PetscObjectQuery((PetscObject)fetidppc_ctx->pc,"__KSPFETIDP_iV",(PetscObject*)&iV));
747     if (iV) {
748       PetscCall(PetscOptionsGetBool(NULL,((PetscObject)fetimat)->prefix,"-pc_discrete_harmonic",&discrete_harmonic,NULL));
749     }
750     if (discrete_harmonic) {
751       KSP             sksp;
752       PC              pc;
753       PCBDDCSubSchurs sub_schurs = pcbddc->sub_schurs;
754       Mat             A_II,A_IB,A_BI;
755       IS              iP = NULL;
756       PetscBool       isshell,reuse = PETSC_FALSE;
757       KSPType         ksptype;
758       const char      *prefix;
759 
760       /*
761         We constructs a Schur complement for
762 
763         | A_II A_ID |
764         | A_DI A_DD |
765 
766         instead of
767 
768         | A_II  B^t_II A_ID |
769         | B_II -C_II   B_ID |
770         | A_DI  B^t_ID A_DD |
771 
772       */
773       if (sub_schurs && sub_schurs->reuse_solver) {
774         PetscCall(PetscObjectQuery((PetscObject)sub_schurs->A,"__KSPFETIDP_iP",(PetscObject*)&iP));
775         if (iP) reuse = PETSC_TRUE;
776       }
777       if (!reuse) {
778         IS       aB;
779         PetscInt nb;
780         PetscCall(ISGetLocalSize(pcis->is_B_local,&nb));
781         PetscCall(ISCreateStride(PetscObjectComm((PetscObject)pcis->A_II),nb,0,1,&aB));
782         PetscCall(MatCreateSubMatrix(pcis->A_II,iV,iV,MAT_INITIAL_MATRIX,&A_II));
783         PetscCall(MatCreateSubMatrix(pcis->A_IB,iV,aB,MAT_INITIAL_MATRIX,&A_IB));
784         PetscCall(MatCreateSubMatrix(pcis->A_BI,aB,iV,MAT_INITIAL_MATRIX,&A_BI));
785         PetscCall(ISDestroy(&aB));
786       } else {
787         PetscCall(MatCreateSubMatrix(sub_schurs->A,pcis->is_I_local,pcis->is_B_local,MAT_INITIAL_MATRIX,&A_IB));
788         PetscCall(MatCreateSubMatrix(sub_schurs->A,pcis->is_B_local,pcis->is_I_local,MAT_INITIAL_MATRIX,&A_BI));
789         PetscCall(PetscObjectReference((PetscObject)pcis->A_II));
790         A_II = pcis->A_II;
791       }
792       PetscCall(MatCreateSchurComplement(A_II,A_II,A_IB,A_BI,pcis->A_BB,&fetidppc_ctx->S_j));
793 
794       /* propagate settings of solver */
795       PetscCall(MatSchurComplementGetKSP(fetidppc_ctx->S_j,&sksp));
796       PetscCall(KSPGetType(pcis->ksp_D,&ksptype));
797       PetscCall(KSPSetType(sksp,ksptype));
798       PetscCall(KSPGetPC(pcis->ksp_D,&pc));
799       PetscCall(PetscObjectTypeCompare((PetscObject)pc,PCSHELL,&isshell));
800       if (!isshell) {
801         MatSolverType    solver;
802         PCType           pctype;
803 
804         PetscCall(PCGetType(pc,&pctype));
805         PetscCall(PCFactorGetMatSolverType(pc,(MatSolverType*)&solver));
806         PetscCall(KSPGetPC(sksp,&pc));
807         PetscCall(PCSetType(pc,pctype));
808         if (solver) {
809           PetscCall(PCFactorSetMatSolverType(pc,solver));
810         }
811       } else {
812         PetscCall(KSPGetPC(sksp,&pc));
813         PetscCall(PCSetType(pc,PCLU));
814       }
815       PetscCall(MatDestroy(&A_II));
816       PetscCall(MatDestroy(&A_IB));
817       PetscCall(MatDestroy(&A_BI));
818       PetscCall(MatGetOptionsPrefix(fetimat,&prefix));
819       PetscCall(KSPSetOptionsPrefix(sksp,prefix));
820       PetscCall(KSPAppendOptionsPrefix(sksp,"harmonic_"));
821       PetscCall(KSPSetFromOptions(sksp));
822       if (reuse) {
823         PetscCall(KSPSetPC(sksp,sub_schurs->reuse_solver->interior_solver));
824         PetscCall(PetscObjectIncrementTabLevel((PetscObject)sub_schurs->reuse_solver->interior_solver,(PetscObject)sksp,0));
825       }
826     } else { /* default Dirichlet preconditioner is pde-harmonic */
827       PetscCall(MatCreateSchurComplement(pcis->A_II,pcis->A_II,pcis->A_IB,pcis->A_BI,pcis->A_BB,&fetidppc_ctx->S_j));
828       PetscCall(MatSchurComplementSetKSP(fetidppc_ctx->S_j,pcis->ksp_D));
829     }
830   } else {
831     PetscCall(PetscObjectReference((PetscObject)pcis->A_BB));
832     fetidppc_ctx->S_j = pcis->A_BB;
833   }
834   /* saddle-point */
835   if (mat_ctx->xPg) {
836     PetscCall(PetscObjectReference((PetscObject)mat_ctx->xPg));
837     fetidppc_ctx->xPg = mat_ctx->xPg;
838     PetscCall(PetscObjectReference((PetscObject)mat_ctx->yPg));
839     fetidppc_ctx->yPg = mat_ctx->yPg;
840   }
841   PetscFunctionReturn(0);
842 }
843 
844 PetscErrorCode FETIDPMatMult_Kernel(Mat fetimat, Vec x, Vec y, PetscBool trans)
845 {
846   FETIDPMat_ctx  mat_ctx;
847   PC_BDDC        *pcbddc;
848   PC_IS          *pcis;
849 
850   PetscFunctionBegin;
851   PetscCall(MatShellGetContext(fetimat,&mat_ctx));
852   pcis = (PC_IS*)mat_ctx->pc->data;
853   pcbddc = (PC_BDDC*)mat_ctx->pc->data;
854   /* Application of B_delta^T */
855   PetscCall(VecSet(pcis->vec1_B,0.));
856   PetscCall(VecScatterBegin(mat_ctx->l2g_lambda,x,mat_ctx->lambda_local,INSERT_VALUES,SCATTER_REVERSE));
857   PetscCall(VecScatterEnd(mat_ctx->l2g_lambda,x,mat_ctx->lambda_local,INSERT_VALUES,SCATTER_REVERSE));
858   PetscCall(MatMultTranspose(mat_ctx->B_delta,mat_ctx->lambda_local,pcis->vec1_B));
859 
860   /* Add contribution from saddle point */
861   if (mat_ctx->l2g_p) {
862     PetscCall(VecScatterBegin(mat_ctx->l2g_p,x,mat_ctx->vP,INSERT_VALUES,SCATTER_REVERSE));
863     PetscCall(VecScatterEnd(mat_ctx->l2g_p,x,mat_ctx->vP,INSERT_VALUES,SCATTER_REVERSE));
864     if (pcbddc->switch_static) {
865       if (trans) {
866         PetscCall(MatMultTranspose(mat_ctx->B_BI,mat_ctx->vP,pcis->vec1_D));
867       } else {
868         PetscCall(MatMult(mat_ctx->Bt_BI,mat_ctx->vP,pcis->vec1_D));
869       }
870     }
871     if (trans) {
872       PetscCall(MatMultTransposeAdd(mat_ctx->B_BB,mat_ctx->vP,pcis->vec1_B,pcis->vec1_B));
873     } else {
874       PetscCall(MatMultAdd(mat_ctx->Bt_BB,mat_ctx->vP,pcis->vec1_B,pcis->vec1_B));
875     }
876   } else {
877     if (pcbddc->switch_static) {
878       PetscCall(VecSet(pcis->vec1_D,0.0));
879     }
880   }
881   /* Application of \widetilde{S}^-1 */
882   PetscCall(PetscArrayzero(pcbddc->benign_p0,pcbddc->benign_n));
883   PetscCall(PCBDDCApplyInterfacePreconditioner(mat_ctx->pc,trans));
884   PetscCall(PetscArrayzero(pcbddc->benign_p0,pcbddc->benign_n));
885   PetscCall(VecSet(y,0.0));
886   /* Application of B_delta */
887   PetscCall(MatMult(mat_ctx->B_delta,pcis->vec1_B,mat_ctx->lambda_local));
888   /* Contribution from boundary pressures */
889   if (mat_ctx->C) {
890     const PetscScalar *lx;
891     PetscScalar       *ly;
892 
893     /* pressure ordered first in the local part of x and y */
894     PetscCall(VecGetArrayRead(x,&lx));
895     PetscCall(VecGetArray(y,&ly));
896     PetscCall(VecPlaceArray(mat_ctx->xPg,lx));
897     PetscCall(VecPlaceArray(mat_ctx->yPg,ly));
898     if (trans) {
899       PetscCall(MatMultTranspose(mat_ctx->C,mat_ctx->xPg,mat_ctx->yPg));
900     } else {
901       PetscCall(MatMult(mat_ctx->C,mat_ctx->xPg,mat_ctx->yPg));
902     }
903     PetscCall(VecResetArray(mat_ctx->xPg));
904     PetscCall(VecResetArray(mat_ctx->yPg));
905     PetscCall(VecRestoreArrayRead(x,&lx));
906     PetscCall(VecRestoreArray(y,&ly));
907   }
908   /* Add contribution from saddle point */
909   if (mat_ctx->l2g_p) {
910     if (trans) {
911       PetscCall(MatMultTranspose(mat_ctx->Bt_BB,pcis->vec1_B,mat_ctx->vP));
912     } else {
913       PetscCall(MatMult(mat_ctx->B_BB,pcis->vec1_B,mat_ctx->vP));
914     }
915     if (pcbddc->switch_static) {
916       if (trans) {
917         PetscCall(MatMultTransposeAdd(mat_ctx->Bt_BI,pcis->vec1_D,mat_ctx->vP,mat_ctx->vP));
918       } else {
919         PetscCall(MatMultAdd(mat_ctx->B_BI,pcis->vec1_D,mat_ctx->vP,mat_ctx->vP));
920       }
921     }
922     PetscCall(VecScatterBegin(mat_ctx->l2g_p,mat_ctx->vP,y,ADD_VALUES,SCATTER_FORWARD));
923     PetscCall(VecScatterEnd(mat_ctx->l2g_p,mat_ctx->vP,y,ADD_VALUES,SCATTER_FORWARD));
924   }
925   PetscCall(VecScatterBegin(mat_ctx->l2g_lambda,mat_ctx->lambda_local,y,ADD_VALUES,SCATTER_FORWARD));
926   PetscCall(VecScatterEnd(mat_ctx->l2g_lambda,mat_ctx->lambda_local,y,ADD_VALUES,SCATTER_FORWARD));
927   PetscFunctionReturn(0);
928 }
929 
930 PetscErrorCode FETIDPMatMult(Mat fetimat, Vec x, Vec y)
931 {
932   PetscFunctionBegin;
933   PetscCall(FETIDPMatMult_Kernel(fetimat,x,y,PETSC_FALSE));
934   PetscFunctionReturn(0);
935 }
936 
937 PetscErrorCode FETIDPMatMultTranspose(Mat fetimat, Vec x, Vec y)
938 {
939   PetscFunctionBegin;
940   PetscCall(FETIDPMatMult_Kernel(fetimat,x,y,PETSC_TRUE));
941   PetscFunctionReturn(0);
942 }
943 
944 PetscErrorCode FETIDPPCApply_Kernel(PC fetipc, Vec x, Vec y, PetscBool trans)
945 {
946   FETIDPPC_ctx   pc_ctx;
947   PC_IS          *pcis;
948 
949   PetscFunctionBegin;
950   PetscCall(PCShellGetContext(fetipc,&pc_ctx));
951   pcis = (PC_IS*)pc_ctx->pc->data;
952   /* Application of B_Ddelta^T */
953   PetscCall(VecScatterBegin(pc_ctx->l2g_lambda,x,pc_ctx->lambda_local,INSERT_VALUES,SCATTER_REVERSE));
954   PetscCall(VecScatterEnd(pc_ctx->l2g_lambda,x,pc_ctx->lambda_local,INSERT_VALUES,SCATTER_REVERSE));
955   PetscCall(VecSet(pcis->vec2_B,0.0));
956   PetscCall(MatMultTranspose(pc_ctx->B_Ddelta,pc_ctx->lambda_local,pcis->vec2_B));
957   /* Application of local Schur complement */
958   if (trans) {
959     PetscCall(MatMultTranspose(pc_ctx->S_j,pcis->vec2_B,pcis->vec1_B));
960   } else {
961     PetscCall(MatMult(pc_ctx->S_j,pcis->vec2_B,pcis->vec1_B));
962   }
963   /* Application of B_Ddelta */
964   PetscCall(MatMult(pc_ctx->B_Ddelta,pcis->vec1_B,pc_ctx->lambda_local));
965   PetscCall(VecSet(y,0.0));
966   PetscCall(VecScatterBegin(pc_ctx->l2g_lambda,pc_ctx->lambda_local,y,ADD_VALUES,SCATTER_FORWARD));
967   PetscCall(VecScatterEnd(pc_ctx->l2g_lambda,pc_ctx->lambda_local,y,ADD_VALUES,SCATTER_FORWARD));
968   PetscFunctionReturn(0);
969 }
970 
971 PetscErrorCode FETIDPPCApply(PC pc, Vec x, Vec y)
972 {
973   PetscFunctionBegin;
974   PetscCall(FETIDPPCApply_Kernel(pc,x,y,PETSC_FALSE));
975   PetscFunctionReturn(0);
976 }
977 
978 PetscErrorCode FETIDPPCApplyTranspose(PC pc, Vec x, Vec y)
979 {
980   PetscFunctionBegin;
981   PetscCall(FETIDPPCApply_Kernel(pc,x,y,PETSC_TRUE));
982   PetscFunctionReturn(0);
983 }
984 
985 PetscErrorCode FETIDPPCView(PC pc, PetscViewer viewer)
986 {
987   FETIDPPC_ctx      pc_ctx;
988   PetscBool         iascii;
989   PetscViewer       sviewer;
990 
991   PetscFunctionBegin;
992   PetscCall(PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii));
993   if (iascii) {
994     PetscMPIInt rank;
995     PetscBool   isschur,isshell;
996 
997     PetscCall(PCShellGetContext(pc,&pc_ctx));
998     PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)pc),&rank));
999     PetscCall(PetscObjectTypeCompare((PetscObject)pc_ctx->S_j,MATSCHURCOMPLEMENT,&isschur));
1000     if (isschur) {
1001       PetscCall(PetscViewerASCIIPrintf(viewer,"  Dirichlet preconditioner (just from rank 0)\n"));
1002     } else {
1003       PetscCall(PetscViewerASCIIPrintf(viewer,"  Lumped preconditioner (just from rank 0)\n"));
1004     }
1005     PetscCall(PetscViewerGetSubViewer(viewer,PetscObjectComm((PetscObject)pc_ctx->S_j),&sviewer));
1006     if (rank == 0) {
1007       PetscCall(PetscViewerPushFormat(sviewer,PETSC_VIEWER_ASCII_INFO));
1008       PetscCall(PetscViewerASCIIPushTab(sviewer));
1009       PetscCall(MatView(pc_ctx->S_j,sviewer));
1010       PetscCall(PetscViewerASCIIPopTab(sviewer));
1011       PetscCall(PetscViewerPopFormat(sviewer));
1012     }
1013     PetscCall(PetscViewerRestoreSubViewer(viewer,PetscObjectComm((PetscObject)pc_ctx->S_j),&sviewer));
1014     PetscCall(PetscObjectTypeCompare((PetscObject)pc_ctx->B_Ddelta,MATSHELL,&isshell));
1015     if (isshell) {
1016       BDdelta_DN ctx;
1017       PetscCall(PetscViewerASCIIPrintf(viewer,"  FETI-DP BDdelta: DB^t * (B D^-1 B^t)^-1 for deluxe scaling (just from rank 0)\n"));
1018       PetscCall(MatShellGetContext(pc_ctx->B_Ddelta,&ctx));
1019       PetscCall(PetscViewerGetSubViewer(viewer,PetscObjectComm((PetscObject)pc_ctx->S_j),&sviewer));
1020       if (rank == 0) {
1021         PetscInt tl;
1022 
1023         PetscCall(PetscViewerASCIIGetTab(sviewer,&tl));
1024         PetscCall(PetscObjectSetTabLevel((PetscObject)ctx->kBD,tl));
1025         PetscCall(KSPView(ctx->kBD,sviewer));
1026         PetscCall(PetscViewerPushFormat(sviewer,PETSC_VIEWER_ASCII_INFO));
1027         PetscCall(MatView(ctx->BD,sviewer));
1028         PetscCall(PetscViewerPopFormat(sviewer));
1029       }
1030       PetscCall(PetscViewerRestoreSubViewer(viewer,PetscObjectComm((PetscObject)pc_ctx->S_j),&sviewer));
1031     }
1032     PetscCall(PetscViewerFlush(viewer));
1033   }
1034   PetscFunctionReturn(0);
1035 }
1036