xref: /petsc/src/ksp/pc/impls/mg/fmg.c (revision ccb4e88a40f0b86eaeca07ff64c64e4de2fae686)
1 /*
2      Full multigrid using either additive or multiplicative V or W cycle
3 */
4 #include <petsc/private/pcmgimpl.h>
5 
6 PetscErrorCode PCMGFCycle_Private(PC pc,PC_MG_Levels **mglevels,PetscBool transpose,PetscBool matapp)
7 {
8   PetscErrorCode ierr;
9   PetscInt       i,l = mglevels[0]->levels;
10 
11   PetscFunctionBegin;
12   if (!transpose) {
13     /* restrict the RHS through all levels to coarsest. */
14     for (i=l-1; i>0; i--) {
15       if (mglevels[i]->eventinterprestrict) {ierr = PetscLogEventBegin(mglevels[i]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);}
16       if (matapp) { ierr = MatMatRestrict(mglevels[i]->restrct,mglevels[i]->B,&mglevels[i-1]->B);CHKERRQ(ierr); }
17       else { ierr = MatRestrict(mglevels[i]->restrct,mglevels[i]->b,mglevels[i-1]->b);CHKERRQ(ierr); }
18       if (mglevels[i]->eventinterprestrict) {ierr = PetscLogEventEnd(mglevels[i]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);}
19     }
20 
21     /* work our way up through the levels */
22     if (matapp) {
23       if (!mglevels[0]->X) {
24         ierr = MatDuplicate(mglevels[0]->B,MAT_DO_NOT_COPY_VALUES,&mglevels[0]->X);CHKERRQ(ierr);
25       } else {
26         ierr = MatZeroEntries(mglevels[0]->X);CHKERRQ(ierr);
27       }
28     } else {
29       ierr = VecZeroEntries(mglevels[0]->x);CHKERRQ(ierr);
30     }
31     for (i=0; i<l-1; i++) {
32       ierr = PCMGMCycle_Private(pc,&mglevels[i],transpose,matapp,NULL);CHKERRQ(ierr);
33       if (mglevels[i+1]->eventinterprestrict) {ierr = PetscLogEventBegin(mglevels[i+1]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);}
34       if (matapp) { ierr = MatMatInterpolate(mglevels[i+1]->interpolate,mglevels[i]->X,&mglevels[i+1]->X);CHKERRQ(ierr); }
35       else { ierr = MatInterpolate(mglevels[i+1]->interpolate,mglevels[i]->x,mglevels[i+1]->x);CHKERRQ(ierr); }
36       if (mglevels[i+1]->eventinterprestrict) {ierr = PetscLogEventEnd(mglevels[i+1]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);}
37     }
38     ierr = PCMGMCycle_Private(pc,&mglevels[l-1],transpose,matapp,NULL);CHKERRQ(ierr);
39   } else {
40     ierr = PCMGMCycle_Private(pc,&mglevels[l-1],transpose,matapp,NULL);CHKERRQ(ierr);
41     for (i=l-2; i>=0; i--) {
42       if (mglevels[i+1]->eventinterprestrict) {ierr = PetscLogEventBegin(mglevels[i+1]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);}
43       if (matapp) { ierr = MatMatRestrict(mglevels[i+1]->interpolate,mglevels[i+1]->X,&mglevels[i]->X);CHKERRQ(ierr); }
44       else { ierr = MatRestrict(mglevels[i+1]->interpolate,mglevels[i+1]->x,mglevels[i]->x);CHKERRQ(ierr); }
45       if (mglevels[i+1]->eventinterprestrict) {ierr = PetscLogEventEnd(mglevels[i+1]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);}
46       ierr = PCMGMCycle_Private(pc,&mglevels[i],transpose,matapp,NULL);CHKERRQ(ierr);
47     }
48     for (i=1; i<l; i++) {
49       if (mglevels[i]->eventinterprestrict) {ierr = PetscLogEventBegin(mglevels[i]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);}
50       if (matapp) { ierr = MatMatInterpolate(mglevels[i]->restrct,mglevels[i-1]->B,&mglevels[i]->B);CHKERRQ(ierr); }
51       else { ierr = MatInterpolate(mglevels[i]->restrct,mglevels[i-1]->b,mglevels[i]->b);CHKERRQ(ierr); }
52       if (mglevels[i]->eventinterprestrict) {ierr = PetscLogEventEnd(mglevels[i]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);}
53     }
54   }
55   PetscFunctionReturn(0);
56 }
57 
58 PetscErrorCode PCMGKCycle_Private(PC pc,PC_MG_Levels **mglevels,PetscBool transpose,PetscBool matapp)
59 {
60   PetscErrorCode ierr;
61   PetscInt       i,l = mglevels[0]->levels;
62 
63   PetscFunctionBegin;
64   /* restrict the RHS through all levels to coarsest. */
65   for (i=l-1; i>0; i--) {
66     if (mglevels[i]->eventinterprestrict) {ierr = PetscLogEventBegin(mglevels[i]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);}
67     if (matapp) { ierr = MatMatRestrict(mglevels[i]->restrct,mglevels[i]->B,&mglevels[i-1]->B);CHKERRQ(ierr); }
68     else { ierr = MatRestrict(mglevels[i]->restrct,mglevels[i]->b,mglevels[i-1]->b);CHKERRQ(ierr); }
69     if (mglevels[i]->eventinterprestrict) {ierr = PetscLogEventEnd(mglevels[i]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);}
70   }
71 
72   /* work our way up through the levels */
73   if (matapp) {
74     if (!mglevels[0]->X) {
75       ierr = MatDuplicate(mglevels[0]->B,MAT_DO_NOT_COPY_VALUES,&mglevels[0]->X);CHKERRQ(ierr);
76     } else {
77       ierr = MatZeroEntries(mglevels[0]->X);CHKERRQ(ierr);
78     }
79   } else {
80     ierr = VecZeroEntries(mglevels[0]->x);CHKERRQ(ierr);
81   }
82   for (i=0; i<l-1; i++) {
83     if (mglevels[i]->eventsmoothsolve) {ierr = PetscLogEventBegin(mglevels[i]->eventsmoothsolve,0,0,0,0);CHKERRQ(ierr);}
84     if (matapp) {
85       ierr = KSPMatSolve(mglevels[i]->smoothd,mglevels[i]->B,mglevels[i]->X);CHKERRQ(ierr);
86       ierr = KSPCheckSolve(mglevels[i]->smoothd,pc,NULL);CHKERRQ(ierr);
87     } else {
88       ierr = KSPSolve(mglevels[i]->smoothd,mglevels[i]->b,mglevels[i]->x);CHKERRQ(ierr);
89       ierr = KSPCheckSolve(mglevels[i]->smoothd,pc,mglevels[i]->x);CHKERRQ(ierr);
90     }
91     if (mglevels[i]->eventsmoothsolve) {ierr = PetscLogEventEnd(mglevels[i]->eventsmoothsolve,0,0,0,0);CHKERRQ(ierr);}
92     if (mglevels[i+1]->eventinterprestrict) {ierr = PetscLogEventBegin(mglevels[i+1]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);}
93     if (matapp) { ierr = MatMatInterpolate(mglevels[i+1]->interpolate,mglevels[i]->X,&mglevels[i+1]->X);CHKERRQ(ierr); }
94     else { ierr = MatInterpolate(mglevels[i+1]->interpolate,mglevels[i]->x,mglevels[i+1]->x);CHKERRQ(ierr); }
95     if (mglevels[i+1]->eventinterprestrict) {ierr = PetscLogEventEnd(mglevels[i+1]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);}
96   }
97   if (mglevels[l-1]->eventsmoothsolve) {ierr = PetscLogEventBegin(mglevels[l-1]->eventsmoothsolve,0,0,0,0);CHKERRQ(ierr);}
98   if (matapp) {
99     ierr = KSPMatSolve(mglevels[l-1]->smoothd,mglevels[l-1]->B,mglevels[l-1]->X);CHKERRQ(ierr);
100     ierr = KSPCheckSolve(mglevels[l-1]->smoothd,pc,NULL);CHKERRQ(ierr);
101   } else {
102     ierr = KSPSolve(mglevels[l-1]->smoothd,mglevels[l-1]->b,mglevels[l-1]->x);CHKERRQ(ierr);
103     ierr = KSPCheckSolve(mglevels[l-1]->smoothd,pc,mglevels[l-1]->x);CHKERRQ(ierr);
104   }
105   if (mglevels[l-1]->eventsmoothsolve) {ierr = PetscLogEventEnd(mglevels[l-1]->eventsmoothsolve,0,0,0,0);CHKERRQ(ierr);}
106   PetscFunctionReturn(0);
107 }
108