xref: /petsc/src/snes/impls/nasm/nasm.c (revision 78f90cf16bc33c288667ec3c8d2b69a906b6e63c)
1 #include <petsc-private/snesimpl.h>             /*I   "petscsnes.h"   I*/
2 #include <petscdm.h>
3 
4 typedef struct {
5   PetscInt   n;                   /* local subdomains */
6   SNES       *subsnes;            /* nonlinear solvers for each subdomain */
7   Vec        *x;                  /* solution vectors */
8   Vec        *xl;                 /* solution local vectors */
9   Vec        *y;                  /* step vectors */
10   Vec        *b;                  /* rhs vectors */
11   VecScatter *oscatter;           /* scatter from global space to the subdomain global space */
12   VecScatter *iscatter;           /* scatter from global space to the nonoverlapping subdomain space */
13   VecScatter *gscatter;           /* scatter from global space to the subdomain local space */
14   PCASMType  type;                /* ASM type */
15   PetscBool  usesdm;              /* use the DM for setting up the subproblems */
16   PetscBool  finaljacobian;       /* compute the jacobian of the converged solution */
17 
18   /* logging events */
19   PetscLogEvent eventrestrictinterp;
20   PetscLogEvent eventsubsolve;
21 } SNES_NASM;
22 
23 const char *const SNESNASMTypes[] = {"NONE","RESTRICT","INTERPOLATE","BASIC","PCASMType","PC_ASM_",0};
24 
25 #undef __FUNCT__
26 #define __FUNCT__ "SNESReset_NASM"
27 PetscErrorCode SNESReset_NASM(SNES snes)
28 {
29   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
30   PetscErrorCode ierr;
31   PetscInt       i;
32 
33   PetscFunctionBegin;
34   for (i=0; i<nasm->n; i++) {
35     if (nasm->xl) { ierr = VecDestroy(&nasm->xl[i]);CHKERRQ(ierr); }
36     if (nasm->x) { ierr = VecDestroy(&nasm->x[i]);CHKERRQ(ierr); }
37     if (nasm->y) { ierr = VecDestroy(&nasm->y[i]);CHKERRQ(ierr); }
38     if (nasm->b) { ierr = VecDestroy(&nasm->b[i]);CHKERRQ(ierr); }
39 
40     if (nasm->subsnes) { ierr = SNESDestroy(&nasm->subsnes[i]);CHKERRQ(ierr); }
41     if (nasm->oscatter) { ierr = VecScatterDestroy(&nasm->oscatter[i]);CHKERRQ(ierr); }
42     if (nasm->iscatter) { ierr = VecScatterDestroy(&nasm->iscatter[i]);CHKERRQ(ierr); }
43     if (nasm->gscatter) { ierr = VecScatterDestroy(&nasm->gscatter[i]);CHKERRQ(ierr); }
44   }
45 
46   if (nasm->x) {ierr = PetscFree(nasm->x);CHKERRQ(ierr);}
47   if (nasm->xl) {ierr = PetscFree(nasm->xl);CHKERRQ(ierr);}
48   if (nasm->y) {ierr = PetscFree(nasm->y);CHKERRQ(ierr);}
49   if (nasm->b) {ierr = PetscFree(nasm->b);CHKERRQ(ierr);}
50 
51   if (nasm->subsnes) {ierr = PetscFree(nasm->subsnes);CHKERRQ(ierr);}
52   if (nasm->oscatter) {ierr = PetscFree(nasm->oscatter);CHKERRQ(ierr);}
53   if (nasm->iscatter) {ierr = PetscFree(nasm->iscatter);CHKERRQ(ierr);}
54   if (nasm->gscatter) {ierr = PetscFree(nasm->gscatter);CHKERRQ(ierr);}
55 
56   nasm->eventrestrictinterp = 0;
57   nasm->eventsubsolve = 0;
58   PetscFunctionReturn(0);
59 }
60 
61 #undef __FUNCT__
62 #define __FUNCT__ "SNESDestroy_NASM"
63 PetscErrorCode SNESDestroy_NASM(SNES snes)
64 {
65   PetscErrorCode ierr;
66 
67   PetscFunctionBegin;
68   ierr = SNESReset_NASM(snes);CHKERRQ(ierr);
69   ierr = PetscFree(snes->data);CHKERRQ(ierr);
70   PetscFunctionReturn(0);
71 }
72 
73 #undef __FUNCT__
74 #define __FUNCT__ "DMGlobalToLocalSubDomainDirichletHook_Private"
75 PetscErrorCode DMGlobalToLocalSubDomainDirichletHook_Private(DM dm,Vec g,InsertMode mode,Vec l,void *ctx)
76 {
77   PetscErrorCode ierr;
78   Vec            bcs = (Vec)ctx;
79 
80   PetscFunctionBegin;
81   ierr = VecCopy(bcs,l);CHKERRQ(ierr);
82   PetscFunctionReturn(0);
83 }
84 
85 #undef __FUNCT__
86 #define __FUNCT__ "SNESSetUp_NASM"
87 PetscErrorCode SNESSetUp_NASM(SNES snes)
88 {
89   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
90   PetscErrorCode ierr;
91   DM             dm,subdm;
92   DM             *subdms;
93   PetscInt       i;
94   const char     *optionsprefix;
95   Vec            F;
96   PetscMPIInt    size;
97   KSP            ksp;
98   PC             pc;
99 
100   PetscFunctionBegin;
101   if (!nasm->subsnes) {
102     ierr = SNESGetDM(snes,&dm);CHKERRQ(ierr);
103     if (dm) {
104       nasm->usesdm = PETSC_TRUE;
105       ierr         = DMCreateDomainDecomposition(dm,&nasm->n,NULL,NULL,NULL,&subdms);CHKERRQ(ierr);
106       if (!subdms) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_ARG_WRONGSTATE,"DM has no default decomposition defined.  Set subsolves manually with SNESNASMSetSubdomains().");
107       ierr = DMCreateDomainDecompositionScatters(dm,nasm->n,subdms,&nasm->iscatter,&nasm->oscatter,&nasm->gscatter);CHKERRQ(ierr);
108 
109       ierr = SNESGetOptionsPrefix(snes, &optionsprefix);CHKERRQ(ierr);
110       ierr = PetscMalloc(nasm->n*sizeof(SNES),&nasm->subsnes);CHKERRQ(ierr);
111       for (i=0; i<nasm->n; i++) {
112         ierr = SNESCreate(PETSC_COMM_SELF,&nasm->subsnes[i]);CHKERRQ(ierr);
113         ierr = SNESAppendOptionsPrefix(nasm->subsnes[i],optionsprefix);CHKERRQ(ierr);
114         ierr = SNESAppendOptionsPrefix(nasm->subsnes[i],"sub_");CHKERRQ(ierr);
115         ierr = SNESSetDM(nasm->subsnes[i],subdms[i]);CHKERRQ(ierr);
116         ierr = MPI_Comm_size(PetscObjectComm((PetscObject)nasm->subsnes[i]),&size);CHKERRQ(ierr);
117         if (size == 1) {
118           ierr = SNESGetKSP(nasm->subsnes[i],&ksp);CHKERRQ(ierr);
119           ierr = KSPGetPC(ksp,&pc);CHKERRQ(ierr);
120           ierr = KSPSetType(ksp,KSPPREONLY);CHKERRQ(ierr);
121           ierr = PCSetType(pc,PCLU);CHKERRQ(ierr);
122         }
123         ierr = SNESSetFromOptions(nasm->subsnes[i]);CHKERRQ(ierr);
124         ierr = DMDestroy(&subdms[i]);CHKERRQ(ierr);
125       }
126       ierr = PetscFree(subdms);CHKERRQ(ierr);
127     } else SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE,"Cannot construct local problems automatically without a DM!");
128   } else SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE,"Must set subproblems manually if there is no DM!");
129   /* allocate the global vectors */
130   if (!nasm->x) {
131     ierr = PetscMalloc(nasm->n*sizeof(Vec),&nasm->x);CHKERRQ(ierr);
132     ierr = PetscMemzero(nasm->x,nasm->n*sizeof(Vec));CHKERRQ(ierr);
133   }
134   if (!nasm->xl) {
135     ierr = PetscMalloc(nasm->n*sizeof(Vec),&nasm->xl);CHKERRQ(ierr);
136     ierr = PetscMemzero(nasm->xl,nasm->n*sizeof(Vec));CHKERRQ(ierr);
137   }
138   if (!nasm->y) {
139     ierr = PetscMalloc(nasm->n*sizeof(Vec),&nasm->y);CHKERRQ(ierr);
140     ierr = PetscMemzero(nasm->y,nasm->n*sizeof(Vec));CHKERRQ(ierr);
141   }
142   if (!nasm->b) {
143     ierr = PetscMalloc(nasm->n*sizeof(Vec),&nasm->b);CHKERRQ(ierr);
144     ierr = PetscMemzero(nasm->b,nasm->n*sizeof(Vec));CHKERRQ(ierr);
145   }
146 
147   for (i=0; i<nasm->n; i++) {
148     ierr = SNESGetFunction(nasm->subsnes[i],&F,NULL,NULL);CHKERRQ(ierr);
149     if (!nasm->x[i]) {ierr = VecDuplicate(F,&nasm->x[i]);CHKERRQ(ierr);}
150     if (!nasm->y[i]) {ierr = VecDuplicate(F,&nasm->y[i]);CHKERRQ(ierr);}
151     if (!nasm->b[i]) {ierr = VecDuplicate(F,&nasm->b[i]);CHKERRQ(ierr);}
152     if (!nasm->xl[i]) {
153       ierr = SNESGetDM(nasm->subsnes[i],&subdm);CHKERRQ(ierr);
154       ierr = DMCreateLocalVector(subdm,&nasm->xl[i]);CHKERRQ(ierr);
155     }
156     ierr = DMGlobalToLocalHookAdd(subdm,DMGlobalToLocalSubDomainDirichletHook_Private,NULL,nasm->xl[i]);CHKERRQ(ierr);
157   }
158   if (nasm->finaljacobian) {ierr = SNESSetUpMatrices(snes);CHKERRQ(ierr);}
159   PetscFunctionReturn(0);
160 }
161 
162 #undef __FUNCT__
163 #define __FUNCT__ "SNESSetFromOptions_NASM"
164 PetscErrorCode SNESSetFromOptions_NASM(SNES snes)
165 {
166   PetscErrorCode    ierr;
167   PCASMType         asmtype;
168   PetscBool         flg,monflg;
169   SNES_NASM         *nasm = (SNES_NASM*)snes->data;
170 
171   PetscFunctionBegin;
172   ierr = PetscOptionsHead("Nonlinear Additive Schwartz options");CHKERRQ(ierr);
173   ierr = PetscOptionsEnum("-snes_nasm_type","Type of restriction/extension","",SNESNASMTypes,(PetscEnum)nasm->type,(PetscEnum*)&asmtype,&flg);CHKERRQ(ierr);
174   if (flg) nasm->type = asmtype;
175   flg    = PETSC_FALSE;
176   monflg = PETSC_TRUE;
177   ierr   = PetscOptionsBool("-snes_nasm_log","Log times for subSNES solves and restriction","",monflg,&monflg,&flg);CHKERRQ(ierr);
178   ierr   = PetscOptionsBool("-snes_nasm_finaljacobian","Compute the global jacobian of the final iterate (for ASPIN)","",nasm->finaljacobian,&nasm->finaljacobian,NULL);CHKERRQ(ierr);
179   if (flg) {
180     ierr = PetscLogEventRegister("SNESNASMSubSolve",((PetscObject)snes)->classid,&nasm->eventsubsolve);CHKERRQ(ierr);
181     ierr = PetscLogEventRegister("SNESNASMRestrict",((PetscObject)snes)->classid,&nasm->eventrestrictinterp);CHKERRQ(ierr);
182   }
183   ierr = PetscOptionsTail();CHKERRQ(ierr);
184   PetscFunctionReturn(0);
185 }
186 
187 #undef __FUNCT__
188 #define __FUNCT__ "SNESView_NASM"
189 PetscErrorCode SNESView_NASM(SNES snes, PetscViewer viewer)
190 {
191   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
192   PetscErrorCode ierr;
193   PetscMPIInt    rank;
194   PetscInt       i,N;
195   PetscBool      iascii,isstring;
196   PetscViewer    sviewer;
197   MPI_Comm       comm;
198 
199   PetscFunctionBegin;
200   ierr = PetscObjectGetComm((PetscObject)snes,&comm);CHKERRQ(ierr);
201   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
202   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSTRING,&isstring);CHKERRQ(ierr);
203   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
204   ierr = MPI_Reduce(&nasm->n,&N,1,MPIU_INT,MPIU_SUM,0,comm);CHKERRQ(ierr);
205   if (iascii) {
206     ierr = PetscViewerASCIIPrintf(viewer, "  Nonlinear Additive Schwarz: total subdomain blocks = %D\n",N);CHKERRQ(ierr);
207     ierr = PetscViewerASCIIPrintf(viewer,"  Nonlinear Additive Schwarz: restriction/interpolation type - %s\n",SNESNASMTypes[nasm->type]);CHKERRQ(ierr);
208     ierr = PetscViewerASCIIPrintf(viewer,"  Nonlinear Additive Schwarz: subSNES iterations: %D subKSP iterations: %D\n",SNESNASMTypes[nasm->type]);CHKERRQ(ierr);
209     ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_TRUE);CHKERRQ(ierr);
210     ierr = PetscViewerASCIISynchronizedPrintf(viewer,"  [%d] number of local blocks = %D\n",(int)rank,nasm->n);CHKERRQ(ierr);
211     ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
212     ierr = PetscViewerASCIIPrintf(viewer,"  Local SNES objects:\n");CHKERRQ(ierr);
213     ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
214     if (!rank) {
215       for (i=0; i<nasm->n; i++) {
216         ierr = PetscViewerGetSingleton(viewer,&sviewer);CHKERRQ(ierr);
217         ierr = SNESView(nasm->subsnes[i],sviewer);CHKERRQ(ierr);
218         ierr = PetscViewerRestoreSingleton(viewer,&sviewer);CHKERRQ(ierr);
219       }
220     }
221     ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
222     ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
223     ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_FALSE);CHKERRQ(ierr);
224   } else if (isstring) {
225     ierr = PetscViewerStringSPrintf(viewer," blocks=%D,type=%s",N,SNESNASMTypes[nasm->type]);CHKERRQ(ierr);
226     ierr = PetscViewerGetSingleton(viewer,&sviewer);CHKERRQ(ierr);
227     if (nasm->subsnes && !rank) {ierr = SNESView(nasm->subsnes[0],sviewer);CHKERRQ(ierr);}
228     ierr = PetscViewerRestoreSingleton(viewer,&sviewer);CHKERRQ(ierr);
229   }
230   PetscFunctionReturn(0);
231 }
232 
233 #undef __FUNCT__
234 #define __FUNCT__ "SNESNASMSetSubdomains"
235 /*@
236    SNESNASMSetSubdomains - Manually Set the context required to restrict and solve subdomain problems.
237 
238    Not Collective
239 
240    Input Parameters:
241 +  SNES - the SNES context
242 .  n - the number of local subdomains
243 .  subsnes - solvers defined on the local subdomains
244 .  iscatter - scatters into the nonoverlapping portions of the local subdomains
245 .  oscatter - scatters into the overlapping portions of the local subdomains
246 -  gscatter - scatters into the (ghosted) local vector of the local subdomain
247 
248    Level: intermediate
249 
250 .keywords: SNES, NASM
251 
252 .seealso: SNESNASM, SNESNASMGetSubdomains()
253 @*/
254 PetscErrorCode SNESNASMSetSubdomains(SNES snes,PetscInt n,SNES subsnes[],VecScatter iscatter[],VecScatter oscatter[],VecScatter gscatter[])
255 {
256   PetscErrorCode ierr;
257   PetscErrorCode (*f)(SNES,PetscInt,SNES*,VecScatter*,VecScatter*,VecScatter*);
258 
259   PetscFunctionBegin;
260   ierr = PetscObjectQueryFunction((PetscObject)snes,"SNESNASMSetSubdomains_C",(void (**)(void))&f);CHKERRQ(ierr);
261   ierr = (f)(snes,n,subsnes,iscatter,oscatter,gscatter);CHKERRQ(ierr);
262   PetscFunctionReturn(0);
263 }
264 
265 EXTERN_C_BEGIN
266 #undef __FUNCT__
267 #define __FUNCT__ "SNESNASMSetSubdomains_NASM"
268 PetscErrorCode SNESNASMSetSubdomains_NASM(SNES snes,PetscInt n,SNES subsnes[],VecScatter iscatter[],VecScatter oscatter[],VecScatter gscatter[])
269 {
270   PetscInt       i;
271   PetscErrorCode ierr;
272   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
273 
274   PetscFunctionBegin;
275   if (snes->setupcalled) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE,"SNESNASMSetSubdomains() should be called before calling SNESSetUp().");
276 
277   /* tear down the previously set things */
278   ierr = SNESReset(snes);CHKERRQ(ierr);
279 
280   nasm->n = n;
281   if (oscatter) {
282     for (i=0; i<n; i++) {ierr = PetscObjectReference((PetscObject)oscatter[i]);CHKERRQ(ierr);}
283   }
284   if (iscatter) {
285     for (i=0; i<n; i++) {ierr = PetscObjectReference((PetscObject)iscatter[i]);CHKERRQ(ierr);}
286   }
287   if (gscatter) {
288     for (i=0; i<n; i++) {ierr = PetscObjectReference((PetscObject)gscatter[i]);CHKERRQ(ierr);}
289   }
290   if (oscatter) {
291     ierr = PetscMalloc(n*sizeof(IS),&nasm->oscatter);CHKERRQ(ierr);
292     for (i=0; i<n; i++) {
293       nasm->oscatter[i] = oscatter[i];
294     }
295   }
296   if (iscatter) {
297     ierr = PetscMalloc(n*sizeof(IS),&nasm->iscatter);CHKERRQ(ierr);
298     for (i=0; i<n; i++) {
299       nasm->iscatter[i] = iscatter[i];
300     }
301   }
302   if (gscatter) {
303     ierr = PetscMalloc(n*sizeof(IS),&nasm->gscatter);CHKERRQ(ierr);
304     for (i=0; i<n; i++) {
305       nasm->gscatter[i] = gscatter[i];
306     }
307   }
308 
309   if (subsnes) {
310     ierr = PetscMalloc(n*sizeof(SNES),&nasm->subsnes);CHKERRQ(ierr);
311     for (i=0; i<n; i++) {
312       nasm->subsnes[i] = subsnes[i];
313     }
314   }
315   PetscFunctionReturn(0);
316 }
317 EXTERN_C_END
318 
319 #undef __FUNCT__
320 #define __FUNCT__ "SNESNASMGetSubdomains"
321 /*@
322    SNESNASMGetSubdomains - Get the local subdomain context.
323 
324    Not Collective
325 
326    Input Parameters:
327 .  SNES - the SNES context
328 
329    Output Parameters:
330 +  n - the number of local subdomains
331 .  subsnes - solvers defined on the local subdomains
332 .  iscatter - scatters into the nonoverlapping portions of the local subdomains
333 .  oscatter - scatters into the overlapping portions of the local subdomains
334 -  gscatter - scatters into the (ghosted) local vector of the local subdomain
335 
336    Level: intermediate
337 
338 .keywords: SNES, NASM
339 
340 .seealso: SNESNASM, SNESNASMSetSubdomains()
341 @*/
342 PetscErrorCode SNESNASMGetSubdomains(SNES snes,PetscInt *n,SNES *subsnes[],VecScatter *iscatter[],VecScatter *oscatter[],VecScatter *gscatter[])
343 {
344   PetscErrorCode ierr;
345   PetscErrorCode (*f)(SNES,PetscInt*,SNES**,VecScatter**,VecScatter**,VecScatter**);
346 
347   PetscFunctionBegin;
348   ierr = PetscObjectQueryFunction((PetscObject)snes,"SNESNASMGetSubdomains_C",(void (**)(void))&f);CHKERRQ(ierr);
349   ierr = (f)(snes,n,subsnes,iscatter,oscatter,gscatter);CHKERRQ(ierr);
350   PetscFunctionReturn(0);
351 }
352 
353 EXTERN_C_BEGIN
354 #undef __FUNCT__
355 #define __FUNCT__ "SNESNASMGetSubdomains_NASM"
356 PetscErrorCode SNESNASMGetSubdomains_NASM(SNES snes,PetscInt *n,SNES *subsnes[],VecScatter *iscatter[],VecScatter *oscatter[],VecScatter *gscatter[])
357 {
358   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
359 
360   PetscFunctionBegin;
361   if (n) *n = nasm->n;
362   if (oscatter) *oscatter = nasm->oscatter;
363   if (iscatter) *iscatter = nasm->iscatter;
364   if (gscatter) *gscatter = nasm->gscatter;
365   if (subsnes)  *subsnes  = nasm->subsnes;
366   PetscFunctionReturn(0);
367 }
368 EXTERN_C_END
369 
370 #undef __FUNCT__
371 #define __FUNCT__ "SNESNASMGetSubdomainVecs"
372 /*@
373    SNESNASMGetSubdomainVecs - Get the processor-local subdomain vectors
374 
375    Not Collective
376 
377    Input Parameters:
378 .  SNES - the SNES context
379 
380    Output Parameters:
381 +  n - the number of local subdomains
382 .  x - The subdomain solution vector
383 .  y - The subdomain step vector
384 .  b - The subdomain RHS vector
385 -  xl - The subdomain local vectors (ghosted)
386 
387    Level: developer
388 
389 .keywords: SNES, NASM
390 
391 .seealso: SNESNASM, SNESNASMGetSubdomains()
392 @*/
393 PetscErrorCode SNESNASMGetSubdomainVecs(SNES snes,PetscInt *n,Vec **x,Vec **y,Vec **b, Vec **xl)
394 {
395   PetscErrorCode ierr;
396   PetscErrorCode (*f)(SNES,PetscInt*,Vec**,Vec**,Vec**,Vec**);
397 
398   PetscFunctionBegin;
399   ierr = PetscObjectQueryFunction((PetscObject)snes,"SNESNASMGetSubdomainVecs_C",(void (**)(void))&f);CHKERRQ(ierr);
400   ierr = (f)(snes,n,x,y,b,xl);CHKERRQ(ierr);
401   PetscFunctionReturn(0);
402 }
403 
404 EXTERN_C_BEGIN
405 #undef __FUNCT__
406 #define __FUNCT__ "SNESNASMGetSubdomainVecs_NASM"
407 PetscErrorCode SNESNASMGetSubdomainVecs_NASM(SNES snes,PetscInt *n,Vec **x,Vec **y,Vec **b,Vec **xl)
408 {
409   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
410 
411   PetscFunctionBegin;
412   if (n)  *n  = nasm->n;
413   if (x)  *x  = nasm->x;
414   if (y)  *y  = nasm->y;
415   if (b)  *b  = nasm->b;
416   if (xl) *xl = nasm->xl;
417   PetscFunctionReturn(0);
418 }
419 EXTERN_C_END
420 
421 #undef __FUNCT__
422 #define __FUNCT__ "SNESNASMSetComputeFinalJacobian"
423 /*@
424    SNESNASMSetComputeFinalJacobian - Schedules the computation of the global and subdomain jacobians upon convergence
425 
426    Collective on SNES
427 
428    Input Parameters:
429 +  SNES - the SNES context
430 -  flg - indication of whether to compute the jacobians or not
431 
432    Level: developer
433 
434    Notes: This is used almost exclusively in the implementation of ASPIN, where the converged subdomain and global jacobian
435    is needed at each linear iteration.
436 
437 .keywords: SNES, NASM, ASPIN
438 
439 .seealso: SNESNASM, SNESNASMGetSubdomains()
440 @*/
441 PetscErrorCode SNESNASMSetComputeFinalJacobian(SNES snes,PetscBool flg)
442 {
443   PetscErrorCode (*f)(SNES,PetscBool);
444   PetscErrorCode ierr;
445 
446   PetscFunctionBegin;
447   ierr = PetscObjectQueryFunction((PetscObject)snes,"SNESNASMSetComputeFinalJacobian_C",(void (**)(void))&f);CHKERRQ(ierr);
448   ierr = (f)(snes,flg);CHKERRQ(ierr);
449   PetscFunctionReturn(0);
450 }
451 
452 EXTERN_C_BEGIN
453 #undef __FUNCT__
454 #define __FUNCT__ "SNESNASMSetComputeFinalJacobian_NASM"
455 PetscErrorCode SNESNASMSetComputeFinalJacobian_NASM(SNES snes,PetscBool flg)
456 {
457   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
458 
459   PetscFunctionBegin;
460   nasm->finaljacobian = flg;
461   PetscFunctionReturn(0);
462 }
463 EXTERN_C_END
464 
465 
466 #undef __FUNCT__
467 #define __FUNCT__ "SNESNASMSolveLocal_Private"
468 PetscErrorCode SNESNASMSolveLocal_Private(SNES snes,Vec B,Vec Y,Vec X)
469 {
470   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
471   SNES           subsnes;
472   PetscInt       i;
473   PetscErrorCode ierr;
474   Vec            Xlloc,Xl,Bl,Yl;
475   VecScatter     iscat,oscat,gscat;
476   DM             dm,subdm;
477 
478   PetscFunctionBegin;
479   ierr = SNESGetDM(snes,&dm);CHKERRQ(ierr);
480   ierr = VecSet(Y,0);CHKERRQ(ierr);
481   if (nasm->eventrestrictinterp) {ierr = PetscLogEventBegin(nasm->eventrestrictinterp,snes,0,0,0);CHKERRQ(ierr);}
482   for (i=0; i<nasm->n; i++) {
483     /* scatter the solution to the local solution */
484     Xlloc = nasm->xl[i];
485     gscat   = nasm->gscatter[i];
486     oscat   = nasm->oscatter[i];
487     ierr = VecScatterBegin(gscat,X,Xlloc,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
488     if (B) {
489       /* scatter the RHS to the local RHS */
490       Bl   = nasm->b[i];
491       ierr = VecScatterBegin(oscat,B,Bl,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
492     }
493   }
494   if (nasm->eventrestrictinterp) {ierr = PetscLogEventEnd(nasm->eventrestrictinterp,snes,0,0,0);CHKERRQ(ierr);}
495 
496 
497   if (nasm->eventsubsolve) {ierr = PetscLogEventBegin(nasm->eventsubsolve,snes,0,0,0);CHKERRQ(ierr);}
498   for (i=0; i<nasm->n; i++) {
499     Xl    = nasm->x[i];
500     Xlloc = nasm->xl[i];
501     Yl    = nasm->y[i];
502     subsnes = nasm->subsnes[i];
503     ierr    = SNESGetDM(subsnes,&subdm);CHKERRQ(ierr);
504     iscat   = nasm->iscatter[i];
505     oscat   = nasm->oscatter[i];
506     gscat   = nasm->gscatter[i];
507     ierr = VecScatterEnd(gscat,X,Xlloc,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
508     if (B) {
509       Bl   = nasm->b[i];
510       ierr = VecScatterEnd(oscat,B,Bl,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
511     } else Bl = NULL;
512     ierr = DMSubDomainRestrict(dm,oscat,gscat,subdm);CHKERRQ(ierr);
513     ierr = DMLocalToGlobalBegin(subdm,Xlloc,INSERT_VALUES,Xl);CHKERRQ(ierr);
514     ierr = DMLocalToGlobalEnd(subdm,Xlloc,INSERT_VALUES,Xl);CHKERRQ(ierr);
515     ierr = VecCopy(Xl,Yl);CHKERRQ(ierr);
516     ierr = SNESSolve(subsnes,Bl,Xl);CHKERRQ(ierr);
517     ierr = VecAYPX(Yl,-1.0,Xl);CHKERRQ(ierr);
518     if (nasm->type == PC_ASM_BASIC) {
519       ierr = VecScatterBegin(oscat,Yl,Y,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
520     } else if (nasm->type == PC_ASM_RESTRICT) {
521       ierr = VecScatterBegin(iscat,Yl,Y,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
522     } else SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE,"Only basic and restrict types are supported for SNESNASM");
523   }
524   if (nasm->eventsubsolve) {ierr = PetscLogEventEnd(nasm->eventsubsolve,snes,0,0,0);CHKERRQ(ierr);}
525   if (nasm->eventrestrictinterp) {ierr = PetscLogEventBegin(nasm->eventrestrictinterp,snes,0,0,0);CHKERRQ(ierr);}
526   for (i=0; i<nasm->n; i++) {
527     Yl    = nasm->y[i];
528     iscat   = nasm->iscatter[i];
529     oscat   = nasm->oscatter[i];
530     if (nasm->type == PC_ASM_BASIC) {
531       ierr = VecScatterEnd(oscat,Yl,Y,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
532     } else if (nasm->type == PC_ASM_RESTRICT) {
533       ierr = VecScatterEnd(iscat,Yl,Y,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
534     } else SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE,"Only basic and restrict types are supported for SNESNASM");
535   }
536   if (nasm->eventrestrictinterp) {ierr = PetscLogEventEnd(nasm->eventrestrictinterp,snes,0,0,0);CHKERRQ(ierr);}
537   ierr = VecAXPY(X,1.0,Y);CHKERRQ(ierr);
538   PetscFunctionReturn(0);
539 }
540 
541 #undef __FUNCT__
542 #define __FUNCT__ "SNESNASMComputeFinalJacobian_Private"
543 PetscErrorCode SNESNASMComputeFinalJacobian_Private(SNES snes, Vec X)
544 {
545   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
546   SNES           subsnes;
547   PetscInt       i,lag = 1;
548   PetscErrorCode ierr;
549   Vec            Xlloc,Xl,Fl,F;
550   VecScatter     oscat,gscat;
551   DM             dm,subdm;
552   MatStructure   flg = DIFFERENT_NONZERO_PATTERN;
553   PetscFunctionBegin;
554   F = snes->vec_func;
555   if (snes->normtype == SNES_NORM_NONE) {ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);}
556   ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr);
557   ierr = SNESGetDM(snes,&dm);CHKERRQ(ierr);
558   if (nasm->eventrestrictinterp) {ierr = PetscLogEventBegin(nasm->eventrestrictinterp,snes,0,0,0);CHKERRQ(ierr);}
559   for (i=0; i<nasm->n; i++) {
560     Xlloc = nasm->xl[i];
561     Fl    = nasm->subsnes[i]->vec_func;
562     gscat = nasm->gscatter[i];
563     oscat = nasm->oscatter[i];
564     ierr = VecScatterBegin(gscat,X,Xlloc,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
565     ierr = VecScatterBegin(oscat,F,Fl,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
566   }
567   if (nasm->eventrestrictinterp) {ierr = PetscLogEventEnd(nasm->eventrestrictinterp,snes,0,0,0);CHKERRQ(ierr);}
568   for (i=0; i<nasm->n; i++) {
569     Fl      = nasm->subsnes[i]->vec_func;
570     Xl      = nasm->x[i];
571     Xlloc   = nasm->xl[i];
572     subsnes = nasm->subsnes[i];
573     oscat   = nasm->oscatter[i];
574     gscat   = nasm->gscatter[i];
575     ierr = VecScatterEnd(gscat,X,Xlloc,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
576     ierr = VecScatterEnd(oscat,F,Fl,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
577     ierr = SNESGetDM(subsnes,&subdm);CHKERRQ(ierr);
578     ierr = DMSubDomainRestrict(dm,oscat,gscat,subdm);CHKERRQ(ierr);
579     ierr = DMLocalToGlobalBegin(subdm,Xlloc,INSERT_VALUES,Xl);CHKERRQ(ierr);
580     ierr = DMLocalToGlobalEnd(subdm,Xlloc,INSERT_VALUES,Xl);CHKERRQ(ierr);
581 
582     if (subsnes->lagjacobian == -1)    subsnes->lagjacobian = -2;
583     else if (subsnes->lagjacobian > 1) lag = subsnes->lagjacobian;
584     ierr = SNESComputeJacobian(subsnes,Xl,&subsnes->jacobian,&subsnes->jacobian_pre,&flg);CHKERRQ(ierr);
585     if (lag > 1) subsnes->lagjacobian = lag;
586     ierr = KSPSetOperators(subsnes->ksp,subsnes->jacobian,subsnes->jacobian_pre,flg);CHKERRQ(ierr);
587   }
588   PetscFunctionReturn(0);
589 }
590 
591 #undef __FUNCT__
592 #define __FUNCT__ "SNESSolve_NASM"
593 PetscErrorCode SNESSolve_NASM(SNES snes)
594 {
595   Vec            F;
596   Vec            X;
597   Vec            B;
598   Vec            Y;
599   PetscInt       i;
600   PetscReal      fnorm = 0.0;
601   PetscErrorCode ierr;
602   SNESNormType   normtype;
603   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
604 
605   PetscFunctionBegin;
606   X = snes->vec_sol;
607   Y = snes->vec_sol_update;
608   F = snes->vec_func;
609   B = snes->vec_rhs;
610 
611   ierr         = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
612   snes->iter   = 0;
613   snes->norm   = 0.;
614   ierr         = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
615   snes->reason = SNES_CONVERGED_ITERATING;
616   ierr         = SNESGetNormType(snes, &normtype);CHKERRQ(ierr);
617   if (normtype == SNES_NORM_FUNCTION || normtype == SNES_NORM_INITIAL_ONLY || normtype == SNES_NORM_INITIAL_FINAL_ONLY) {
618     /* compute the initial function and preconditioned update delX */
619     if (!snes->vec_func_init_set) {
620       ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
621       if (snes->domainerror) {
622         snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
623         PetscFunctionReturn(0);
624       }
625     } else snes->vec_func_init_set = PETSC_FALSE;
626 
627     /* convergence test */
628     if (!snes->norm_init_set) {
629       ierr = VecNorm(F, NORM_2, &fnorm);CHKERRQ(ierr); /* fnorm <- ||F||  */
630       if (PetscIsInfOrNanReal(fnorm)) {
631         snes->reason = SNES_DIVERGED_FNORM_NAN;
632         PetscFunctionReturn(0);
633       }
634     } else {
635       fnorm               = snes->norm_init;
636       snes->norm_init_set = PETSC_FALSE;
637     }
638     ierr       = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
639     snes->iter = 0;
640     snes->norm = fnorm;
641     ierr       = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
642     ierr       = SNESLogConvergenceHistory(snes,snes->norm,0);CHKERRQ(ierr);
643     ierr       = SNESMonitor(snes,0,snes->norm);CHKERRQ(ierr);
644 
645     /* set parameter for default relative tolerance convergence test */
646     snes->ttol = fnorm*snes->rtol;
647 
648     /* test convergence */
649     ierr = (*snes->ops->converged)(snes,0,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
650     if (snes->reason) PetscFunctionReturn(0);
651   } else {
652     ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
653     ierr = SNESLogConvergenceHistory(snes,snes->norm,0);CHKERRQ(ierr);
654     ierr = SNESMonitor(snes,0,snes->norm);CHKERRQ(ierr);
655   }
656 
657   /* Call general purpose update function */
658   if (snes->ops->update) {
659     ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
660   }
661 
662   for (i = 0; i < snes->max_its; i++) {
663     ierr = SNESNASMSolveLocal_Private(snes,B,Y,X);CHKERRQ(ierr);
664     if (normtype == SNES_NORM_FUNCTION || ((i == snes->max_its - 1) && (normtype == SNES_NORM_INITIAL_FINAL_ONLY || normtype == SNES_NORM_FINAL_ONLY))) {
665       ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
666       if (snes->domainerror) {
667         snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
668         break;
669       }
670       ierr = VecNorm(F, NORM_2, &fnorm);CHKERRQ(ierr); /* fnorm <- ||F||  */
671       if (PetscIsInfOrNanReal(fnorm)) {
672         snes->reason = SNES_DIVERGED_FNORM_NAN;
673         break;
674       }
675     }
676     /* Monitor convergence */
677     ierr       = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
678     snes->iter = i+1;
679     snes->norm = fnorm;
680     ierr       = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
681     ierr       = SNESLogConvergenceHistory(snes,snes->norm,0);CHKERRQ(ierr);
682     ierr       = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);
683     /* Test for convergence */
684     if (normtype == SNES_NORM_FUNCTION) {ierr = (*snes->ops->converged)(snes,snes->iter,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);}
685     if (snes->reason) break;
686     /* Call general purpose update function */
687     if (snes->ops->update) {ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);}
688   }
689   if (nasm->finaljacobian) {ierr = SNESNASMComputeFinalJacobian_Private(snes,X);CHKERRQ(ierr);}
690   if (normtype == SNES_NORM_FUNCTION) {
691     if (i == snes->max_its) {
692       ierr = PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",snes->max_its);CHKERRQ(ierr);
693       if (!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT;
694     }
695   } else if (!snes->reason) snes->reason = SNES_CONVERGED_ITS; /* NASM is meant to be used as a preconditioner */
696   PetscFunctionReturn(0);
697 }
698 
699 /*MC
700   SNESNASM - Nonlinear Additive Schwartz
701 
702    Options Database:
703 +  -snes_nasm_log - enable logging events for the communication and solve stages
704 .  -snes_nasm_type <basic,restrict> - type of subdomain update used
705 .  -snes_nasm_finaljacobian - compute the local and global jacobians of the final iterate
706 .  -sub_snes_ - options prefix of the subdomain nonlinear solves
707 .  -sub_ksp_ - options prefix of the subdomain Krylov solver
708 -  -sub_pc_ - options prefix of the subdomain preconditioner
709 
710    Level: advanced
711 
712 .seealso: SNESCreate(), SNES, SNESSetType(), SNESType (for list of available types)
713 M*/
714 
715 EXTERN_C_BEGIN
716 #undef __FUNCT__
717 #define __FUNCT__ "SNESCreate_NASM"
718 PetscErrorCode SNESCreate_NASM(SNES snes)
719 {
720   SNES_NASM      *nasm;
721   PetscErrorCode ierr;
722 
723   PetscFunctionBegin;
724   ierr       = PetscNewLog(snes, SNES_NASM, &nasm);CHKERRQ(ierr);
725   snes->data = (void*)nasm;
726 
727   nasm->n        = PETSC_DECIDE;
728   nasm->subsnes  = 0;
729   nasm->x        = 0;
730   nasm->xl       = 0;
731   nasm->y        = 0;
732   nasm->b        = 0;
733   nasm->oscatter = 0;
734   nasm->iscatter = 0;
735   nasm->gscatter = 0;
736 
737   nasm->type = PC_ASM_BASIC;
738   nasm->finaljacobian = PETSC_FALSE;
739 
740   snes->ops->destroy        = SNESDestroy_NASM;
741   snes->ops->setup          = SNESSetUp_NASM;
742   snes->ops->setfromoptions = SNESSetFromOptions_NASM;
743   snes->ops->view           = SNESView_NASM;
744   snes->ops->solve          = SNESSolve_NASM;
745   snes->ops->reset          = SNESReset_NASM;
746 
747   snes->usesksp = PETSC_FALSE;
748   snes->usespc  = PETSC_FALSE;
749 
750   nasm->eventrestrictinterp = 0;
751   nasm->eventsubsolve       = 0;
752 
753   if (!snes->tolerancesset) {
754     snes->max_its   = 10000;
755     snes->max_funcs = 10000;
756   }
757 
758   ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESNASMSetSubdomains_C","SNESNASMSetSubdomains_NASM",
759                                            SNESNASMSetSubdomains_NASM);CHKERRQ(ierr);
760   ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESNASMGetSubdomains_C","SNESNASMGetSubdomains_NASM",
761                                            SNESNASMGetSubdomains_NASM);CHKERRQ(ierr);
762   ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESNASMGetSubdomainVecs_C","SNESNASMGetSubdomainVecs_NASM",
763                                            SNESNASMGetSubdomainVecs_NASM);CHKERRQ(ierr);
764   ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESNASMSetComputeFinalJacobian_C","SNESNASMSetComputeFinalJacobian_NASM",
765                                            SNESNASMSetComputeFinalJacobian_NASM);CHKERRQ(ierr);
766   PetscFunctionReturn(0);
767 }
768 EXTERN_C_END
769