xref: /petsc/include/petsc/private/kspimpl.h (revision c08c7cb97c8a96079b8cb5b2881afccfb9915bda)
1 
2 #ifndef _KSPIMPL_H
3 #define _KSPIMPL_H
4 
5 #include <petscksp.h>
6 #include <petsc/private/petscimpl.h>
7 
8 PETSC_EXTERN PetscBool KSPRegisterAllCalled;
9 PETSC_EXTERN PetscErrorCode KSPRegisterAll(void);
10 PETSC_EXTERN PetscErrorCode KSPGuessRegisterAll(void);
11 PETSC_EXTERN PetscErrorCode KSPMatRegisterAll(void);
12 
13 typedef struct _KSPOps *KSPOps;
14 
15 struct _KSPOps {
16   PetscErrorCode (*buildsolution)(KSP,Vec,Vec*);       /* Returns a pointer to the solution, or
17                                                           calculates the solution in a
18                                                           user-provided area. */
19   PetscErrorCode (*buildresidual)(KSP,Vec,Vec,Vec*);   /* Returns a pointer to the residual, or
20                                                           calculates the residual in a
21                                                           user-provided area.  */
22   PetscErrorCode (*solve)(KSP);                        /* actual solver */
23   PetscErrorCode (*setup)(KSP);
24   PetscErrorCode (*setfromoptions)(PetscOptionItems*,KSP);
25   PetscErrorCode (*publishoptions)(KSP);
26   PetscErrorCode (*computeextremesingularvalues)(KSP,PetscReal*,PetscReal*);
27   PetscErrorCode (*computeeigenvalues)(KSP,PetscInt,PetscReal*,PetscReal*,PetscInt *);
28   PetscErrorCode (*computeritz)(KSP,PetscBool,PetscBool,PetscInt*,Vec[],PetscReal*,PetscReal*);
29   PetscErrorCode (*destroy)(KSP);
30   PetscErrorCode (*view)(KSP,PetscViewer);
31   PetscErrorCode (*reset)(KSP);
32   PetscErrorCode (*load)(KSP,PetscViewer);
33 };
34 
35 typedef struct _KSPGuessOps *KSPGuessOps;
36 
37 struct _KSPGuessOps {
38   PetscErrorCode (*formguess)(KSPGuess,Vec,Vec); /* Form initial guess */
39   PetscErrorCode (*update)(KSPGuess,Vec,Vec);    /* Update database */
40   PetscErrorCode (*setfromoptions)(KSPGuess);
41   PetscErrorCode (*setup)(KSPGuess);
42   PetscErrorCode (*destroy)(KSPGuess);
43   PetscErrorCode (*view)(KSPGuess,PetscViewer);
44   PetscErrorCode (*reset)(KSPGuess);
45 };
46 
47 /*
48    Defines the KSPGuess data structure.
49 */
50 struct _p_KSPGuess {
51   PETSCHEADER(struct _KSPGuessOps);
52   KSP              ksp;       /* the parent KSP */
53   Mat              A;         /* the current linear operator */
54   PetscObjectState omatstate; /* previous linear operator state */
55   void             *data;     /* pointer to the specific implementation */
56 };
57 
58 PETSC_EXTERN PetscErrorCode KSPGuessCreate_Fischer(KSPGuess);
59 PETSC_EXTERN PetscErrorCode KSPGuessCreate_POD(KSPGuess);
60 
61 /*
62      Maximum number of monitors you can run with a single KSP
63 */
64 #define MAXKSPMONITORS 5
65 typedef enum {KSP_SETUP_NEW, KSP_SETUP_NEWMATRIX, KSP_SETUP_NEWRHS} KSPSetUpStage;
66 
67 /*
68    Defines the KSP data structure.
69 */
70 struct _p_KSP {
71   PETSCHEADER(struct _KSPOps);
72   DM              dm;
73   PetscBool       dmAuto;       /* DM was created automatically by KSP */
74   PetscBool       dmActive;     /* KSP should use DM for computing operators */
75   /*------------------------- User parameters--------------------------*/
76   PetscInt        max_it;                     /* maximum number of iterations */
77   KSPGuess        guess;
78   PetscBool       guess_zero,                  /* flag for whether initial guess is 0 */
79                   calc_sings,                  /* calculate extreme Singular Values */
80                   calc_ritz,                   /* calculate (harmonic) Ritz pairs */
81                   guess_knoll;                /* use initial guess of PCApply(ksp->B,b */
82   PCSide          pc_side;                  /* flag for left, right, or symmetric preconditioning */
83   PetscInt        normsupporttable[KSP_NORM_MAX][PC_SIDE_MAX]; /* Table of supported norms and pc_side, see KSPSetSupportedNorm() */
84   PetscReal       rtol,                     /* relative tolerance */
85                   abstol,                     /* absolute tolerance */
86                   ttol,                     /* (not set by user)  */
87                   divtol;                   /* divergence tolerance */
88   PetscReal       rnorm0;                   /* initial residual norm (used for divergence testing) */
89   PetscReal       rnorm;                    /* current residual norm */
90   KSPConvergedReason    reason;
91   PetscBool             errorifnotconverged; /* create an error if the KSPSolve() does not converge */
92 
93   Vec vec_sol,vec_rhs;            /* pointer to where user has stashed
94                                       the solution and rhs, these are
95                                       never touched by the code, only
96                                       passed back to the user */
97   PetscReal     *res_hist;            /* If !0 stores residual at iterations*/
98   PetscReal     *res_hist_alloc;      /* If !0 means user did not provide buffer, needs deallocation */
99   PetscInt      res_hist_len;         /* current size of residual history array */
100   PetscInt      res_hist_max;         /* actual amount of data in residual_history */
101   PetscBool     res_hist_reset;       /* reset history to size zero for each new solve */
102 
103   PetscInt      chknorm;             /* only compute/check norm if iterations is great than this */
104   PetscBool     lagnorm;             /* Lag the residual norm calculation so that it is computed as part of the
105                                         MPI_Allreduce() for computing the inner products for the next iteration. */
106   /* --------User (or default) routines (most return -1 on error) --------*/
107   PetscErrorCode (*monitor[MAXKSPMONITORS])(KSP,PetscInt,PetscReal,void*); /* returns control to user after */
108   PetscErrorCode (*monitordestroy[MAXKSPMONITORS])(void**);         /* */
109   void *monitorcontext[MAXKSPMONITORS];                  /* residual calculation, allows user */
110   PetscInt  numbermonitors;                                   /* to, for instance, print residual norm, etc. */
111 
112   PetscErrorCode (*converged)(KSP,PetscInt,PetscReal,KSPConvergedReason*,void*);
113   PetscErrorCode (*convergeddestroy)(void*);
114   void       *cnvP;
115 
116   void       *user;             /* optional user-defined context */
117 
118   PC         pc;
119 
120   void       *data;                      /* holder for misc stuff associated
121                                    with a particular iterative solver */
122 
123   /* ----------------Default work-area management -------------------- */
124   PetscInt       nwork;
125   Vec            *work;
126 
127   KSPSetUpStage  setupstage;
128   PetscBool      setupnewmatrix; /* true if we need to call ksp->ops->setup with KSP_SETUP_NEWMATRIX */
129 
130   PetscInt       its;       /* number of iterations so far computed in THIS linear solve*/
131   PetscInt       totalits;   /* number of iterations used by this KSP object since it was created */
132 
133   PetscBool      transpose_solve;    /* solve transpose system instead */
134 
135   KSPNormType    normtype;          /* type of norm used for convergence tests */
136 
137   PCSide         pc_side_set;   /* PC type set explicitly by user */
138   KSPNormType    normtype_set;  /* Norm type set explicitly by user */
139 
140   /*   Allow diagonally scaling the matrix before computing the preconditioner or using
141        the Krylov method. Note this is NOT just Jacobi preconditioning */
142 
143   PetscBool    dscale;       /* diagonal scale system; used with KSPSetDiagonalScale() */
144   PetscBool    dscalefix;    /* unscale system after solve */
145   PetscBool    dscalefix2;   /* system has been unscaled */
146   Vec          diagonal;     /* 1/sqrt(diag of matrix) */
147   Vec          truediagonal;
148 
149   PetscBool    skippcsetfromoptions; /* if set then KSPSetFromOptions() does not call PCSetFromOptions() */
150 
151   PetscViewer  eigviewer;   /* Viewer where computed eigenvalues are displayed */
152 
153   PetscErrorCode (*presolve)(KSP,Vec,Vec,void*);
154   PetscErrorCode (*postsolve)(KSP,Vec,Vec,void*);
155   void           *prectx,*postctx;
156 };
157 
158 typedef struct { /* dummy data structure used in KSPMonitorDynamicTolerance() */
159   PetscReal coef;
160   PetscReal bnrm;
161 } KSPDynTolCtx;
162 
163 typedef struct {
164   PetscBool  initialrtol;    /* default relative residual decrease is computing from initial residual, not rhs */
165   PetscBool  mininitialrtol; /* default relative residual decrease is computing from min of initial residual and rhs */
166   Vec        work;
167 } KSPConvergedDefaultCtx;
168 
169 PETSC_STATIC_INLINE PetscErrorCode KSPLogResidualHistory(KSP ksp,PetscReal norm)
170 {
171   PetscErrorCode ierr;
172 
173   PetscFunctionBegin;
174   ierr = PetscObjectSAWsTakeAccess((PetscObject)ksp);CHKERRQ(ierr);
175   if (ksp->res_hist && ksp->res_hist_max > ksp->res_hist_len) {
176     ksp->res_hist[ksp->res_hist_len++] = norm;
177   }
178   ierr = PetscObjectSAWsGrantAccess((PetscObject)ksp);CHKERRQ(ierr);
179   PetscFunctionReturn(0);
180 }
181 
182 PETSC_INTERN PetscErrorCode KSPSetUpNorms_Private(KSP,PetscBool,KSPNormType*,PCSide*);
183 
184 PETSC_INTERN PetscErrorCode KSPPlotEigenContours_Private(KSP,PetscInt,const PetscReal*,const PetscReal*);
185 
186 typedef struct _p_DMKSP *DMKSP;
187 typedef struct _DMKSPOps *DMKSPOps;
188 struct _DMKSPOps {
189   PetscErrorCode (*computeoperators)(KSP,Mat,Mat,void*);
190   PetscErrorCode (*computerhs)(KSP,Vec,void*);
191   PetscErrorCode (*computeinitialguess)(KSP,Vec,void*);
192   PetscErrorCode (*destroy)(DMKSP*);
193   PetscErrorCode (*duplicate)(DMKSP,DMKSP);
194 };
195 
196 struct _p_DMKSP {
197   PETSCHEADER(struct _DMKSPOps);
198   void *operatorsctx;
199   void *rhsctx;
200   void *initialguessctx;
201   void *data;
202 
203   /* This is NOT reference counted. The DM on which this context was first created is cached here to implement one-way
204    * copy-on-write. When DMGetDMKSPWrite() sees a request using a different DM, it makes a copy. Thus, if a user
205    * only interacts directly with one level, e.g., using KSPSetComputeOperators(), then coarse levels are constructed by
206    * PCMG, then the user changes the routine with another call to KSPSetComputeOperators(), it automatically propagates
207    * to all the levels. If instead, they get out a specific level and set the routines on that level, subsequent changes
208    * to the original level will no longer propagate to that level.
209    */
210   DM originaldm;
211 
212   void (*fortran_func_pointers[3])(void); /* Store our own function pointers so they are associated with the DMKSP instead of the DM */
213 };
214 PETSC_EXTERN PetscErrorCode DMGetDMKSP(DM,DMKSP*);
215 PETSC_EXTERN PetscErrorCode DMGetDMKSPWrite(DM,DMKSP*);
216 PETSC_EXTERN PetscErrorCode DMCopyDMKSP(DM,DM);
217 
218 /*
219        These allow the various Krylov methods to apply to either the linear system or its transpose.
220 */
221 PETSC_STATIC_INLINE PetscErrorCode KSP_RemoveNullSpace(KSP ksp,Vec y)
222 {
223   PetscErrorCode ierr;
224   PetscFunctionBegin;
225   if (ksp->pc_side == PC_LEFT) {
226     Mat          A;
227     MatNullSpace nullsp;
228     ierr = PCGetOperators(ksp->pc,&A,NULL);CHKERRQ(ierr);
229     ierr = MatGetNullSpace(A,&nullsp);CHKERRQ(ierr);
230     if (nullsp) {
231       ierr = MatNullSpaceRemove(nullsp,y);CHKERRQ(ierr);
232     }
233   }
234   PetscFunctionReturn(0);
235 }
236 
237 PETSC_STATIC_INLINE PetscErrorCode KSP_RemoveNullSpaceTranspose(KSP ksp,Vec y)
238 {
239   PetscErrorCode ierr;
240   PetscFunctionBegin;
241   if (ksp->pc_side == PC_LEFT) {
242     Mat          A;
243     MatNullSpace nullsp;
244     ierr = PCGetOperators(ksp->pc,&A,NULL);CHKERRQ(ierr);
245     ierr = MatGetTransposeNullSpace(A,&nullsp);CHKERRQ(ierr);
246     if (nullsp) {
247       ierr = MatNullSpaceRemove(nullsp,y);CHKERRQ(ierr);
248     }
249   }
250   PetscFunctionReturn(0);
251 }
252 
253 PETSC_STATIC_INLINE PetscErrorCode KSP_MatMult(KSP ksp,Mat A,Vec x,Vec y)
254 {
255   PetscErrorCode ierr;
256   PetscFunctionBegin;
257   if (!ksp->transpose_solve) {ierr = MatMult(A,x,y);CHKERRQ(ierr);}
258   else                       {ierr = MatMultTranspose(A,x,y);CHKERRQ(ierr);}
259   PetscFunctionReturn(0);
260 }
261 
262 PETSC_STATIC_INLINE PetscErrorCode KSP_MatMultTranspose(KSP ksp,Mat A,Vec x,Vec y)
263 {
264   PetscErrorCode ierr;
265   PetscFunctionBegin;
266   if (!ksp->transpose_solve) {ierr = MatMultTranspose(A,x,y);CHKERRQ(ierr);}
267   else                       {ierr = MatMult(A,x,y);CHKERRQ(ierr);}
268   PetscFunctionReturn(0);
269 }
270 
271 PETSC_STATIC_INLINE PetscErrorCode KSP_PCApply(KSP ksp,Vec x,Vec y)
272 {
273   PetscErrorCode ierr;
274   PetscFunctionBegin;
275   if (!ksp->transpose_solve) {
276     ierr = PCApply(ksp->pc,x,y);CHKERRQ(ierr);
277     ierr = KSP_RemoveNullSpace(ksp,y);CHKERRQ(ierr);
278   } else {
279     ierr = PCApplyTranspose(ksp->pc,x,y);CHKERRQ(ierr);
280     ierr = KSP_RemoveNullSpaceTranspose(ksp,y);CHKERRQ(ierr);
281   }
282   PetscFunctionReturn(0);
283 }
284 
285 PETSC_STATIC_INLINE PetscErrorCode KSP_PCApplyTranspose(KSP ksp,Vec x,Vec y)
286 {
287   PetscErrorCode ierr;
288   PetscFunctionBegin;
289   if (!ksp->transpose_solve) {
290     ierr = PCApplyTranspose(ksp->pc,x,y);CHKERRQ(ierr);
291     ierr = KSP_RemoveNullSpaceTranspose(ksp,y);CHKERRQ(ierr);
292   } else {
293     ierr = PCApply(ksp->pc,x,y);CHKERRQ(ierr);
294     ierr = KSP_RemoveNullSpace(ksp,y);CHKERRQ(ierr);
295   }
296   PetscFunctionReturn(0);
297 }
298 
299 PETSC_STATIC_INLINE PetscErrorCode KSP_PCApplyBAorAB(KSP ksp,Vec x,Vec y,Vec w)
300 {
301   PetscErrorCode ierr;
302   PetscFunctionBegin;
303   if (!ksp->transpose_solve) {
304     ierr = PCApplyBAorAB(ksp->pc,ksp->pc_side,x,y,w);CHKERRQ(ierr);
305     ierr = KSP_RemoveNullSpace(ksp,y);CHKERRQ(ierr);
306   } else {
307     ierr = PCApplyBAorABTranspose(ksp->pc,ksp->pc_side,x,y,w);CHKERRQ(ierr);
308     ierr = KSP_RemoveNullSpaceTranspose(ksp,y);CHKERRQ(ierr);
309   }
310   PetscFunctionReturn(0);
311 }
312 
313 PETSC_STATIC_INLINE PetscErrorCode KSP_PCApplyBAorABTranspose(KSP ksp,Vec x,Vec y,Vec w)
314 {
315   PetscErrorCode ierr;
316   PetscFunctionBegin;
317   if (!ksp->transpose_solve) {
318     ierr = PCApplyBAorABTranspose(ksp->pc,ksp->pc_side,x,y,w);CHKERRQ(ierr);
319   } else {
320     ierr = PCApplyBAorAB(ksp->pc,ksp->pc_side,x,y,w);CHKERRQ(ierr);
321   }
322   PetscFunctionReturn(0);
323 }
324 
325 PETSC_EXTERN PetscLogEvent KSP_GMRESOrthogonalization;
326 PETSC_EXTERN PetscLogEvent KSP_SetUp;
327 PETSC_EXTERN PetscLogEvent KSP_Solve;
328 PETSC_EXTERN PetscLogEvent KSP_Solve_FS_0;
329 PETSC_EXTERN PetscLogEvent KSP_Solve_FS_1;
330 PETSC_EXTERN PetscLogEvent KSP_Solve_FS_2;
331 PETSC_EXTERN PetscLogEvent KSP_Solve_FS_3;
332 PETSC_EXTERN PetscLogEvent KSP_Solve_FS_4;
333 PETSC_EXTERN PetscLogEvent KSP_Solve_FS_S;
334 PETSC_EXTERN PetscLogEvent KSP_Solve_FS_L;
335 PETSC_EXTERN PetscLogEvent KSP_Solve_FS_U;
336 
337 PETSC_INTERN PetscErrorCode MatGetSchurComplement_Basic(Mat,IS,IS,IS,IS,MatReuse,Mat*,MatSchurComplementAinvType,MatReuse,Mat*);
338 PETSC_INTERN PetscErrorCode PCPreSolveChangeRHS(PC,PetscBool*);
339 
340 /*
341     Either generate an error or mark as diverged when a scalar from an inner product is Nan or Inf
342 */
343 #define KSPCheckDot(ksp,beta)           \
344   if (PetscIsInfOrNanScalar(beta)) { \
345     if (ksp->errorifnotconverged) SETERRQ(PetscObjectComm((PetscObject)ksp),PETSC_ERR_NOT_CONVERGED,"KSPSolve has not converged due to Nan or Inf inner product");\
346     else {\
347       PetscErrorCode ierr;\
348       PCFailedReason pcreason;\
349       PetscInt       sendbuf,pcreason_max; \
350       ierr = PCGetSetUpFailedReason(ksp->pc,&pcreason);CHKERRQ(ierr);\
351       sendbuf = (PetscInt)pcreason; \
352       ierr = MPI_Allreduce(&sendbuf,&pcreason_max,1,MPIU_INT,MPI_MAX,PetscObjectComm((PetscObject)ksp));CHKERRQ(ierr); \
353       if (pcreason_max) {\
354         ksp->reason = KSP_DIVERGED_PCSETUP_FAILED;\
355         ierr        = VecSetInf(ksp->vec_sol);CHKERRQ(ierr);\
356       } else {\
357         ksp->reason = KSP_DIVERGED_NANORINF;\
358       }\
359       PetscFunctionReturn(0);\
360     }\
361   }
362 
363 /*
364     Either generate an error or mark as diverged when a real from a norm is Nan or Inf
365 */
366 #define KSPCheckNorm(ksp,beta)           \
367   if (PetscIsInfOrNanReal(beta)) { \
368     if (ksp->errorifnotconverged) SETERRQ(PetscObjectComm((PetscObject)ksp),PETSC_ERR_NOT_CONVERGED,"KSPSolve has not converged due to Nan or Inf norm");\
369     else {\
370       PetscErrorCode ierr;\
371       PCFailedReason pcreason;\
372       PetscInt       sendbuf,pcreason_max; \
373       ierr = PCGetSetUpFailedReason(ksp->pc,&pcreason);CHKERRQ(ierr);\
374       sendbuf = (PetscInt)pcreason; \
375       ierr = MPI_Allreduce(&sendbuf,&pcreason_max,1,MPIU_INT,MPI_MAX,PetscObjectComm((PetscObject)ksp));CHKERRQ(ierr); \
376       if (pcreason_max) {\
377         ksp->reason = KSP_DIVERGED_PCSETUP_FAILED;\
378         ierr        = VecSetInf(ksp->vec_sol);CHKERRQ(ierr);\
379       } else {\
380         ksp->reason = KSP_DIVERGED_NANORINF;\
381       }\
382       PetscFunctionReturn(0);\
383     }\
384   }
385 
386 #endif
387