1 #ifndef lint 2 static char vcid[] = "$Id: mpiaijpc.c,v 1.14 1996/02/25 02:42:31 curfman Exp bsmith $"; 3 #endif 4 /* 5 Defines a block Jacobi preconditioner for the MPIAIJ format. 6 Handles special case of single block per processor. 7 This file knows about storage formats for MPIAIJ matrices. 8 The general case is handled in aijpc.c 9 */ 10 #include "mpiaij.h" 11 #include "src/pc/pcimpl.h" 12 #include "src/pc/impls/bjacobi/bjacobi.h" 13 #include "sles.h" 14 15 typedef struct { 16 Vec x, y; 17 } PC_BJacobiMPIAIJ; 18 19 int PCDestroy_BJacobiMPIAIJ(PetscObject obj) 20 { 21 PC pc = (PC) obj; 22 PC_BJacobi *jac = (PC_BJacobi *) pc->data; 23 PC_BJacobiMPIAIJ *bjac = (PC_BJacobiMPIAIJ *) jac->data; 24 int ierr; 25 26 ierr = SLESDestroy(jac->sles[0]); CHKERRQ(ierr); 27 PetscFree(jac->sles); 28 ierr = VecDestroy(bjac->x); CHKERRQ(ierr); 29 ierr = VecDestroy(bjac->y); CHKERRQ(ierr); 30 if (jac->l_lens) PetscFree(jac->l_lens); 31 if (jac->g_lens) PetscFree(jac->g_lens); 32 if (jac->l_true) PetscFree(jac->l_true); 33 if (jac->g_true) PetscFree(jac->g_true); 34 PetscFree(bjac); PetscFree(jac); 35 return 0; 36 } 37 38 39 int PCSetUpOnBlocks_BJacobiMPIAIJ(PC pc) 40 { 41 int ierr; 42 PC_BJacobi *jac = (PC_BJacobi *) pc->data; 43 PC_BJacobiMPIAIJ *bjac = (PC_BJacobiMPIAIJ *) jac->data; 44 45 ierr = SLESSetUp(jac->sles[0],bjac->x,bjac->y); CHKERRQ(ierr); 46 return 0; 47 } 48 49 int PCApply_BJacobiMPIAIJ(PC pc,Vec x, Vec y) 50 { 51 int ierr,its; 52 PC_BJacobi *jac = (PC_BJacobi *) pc->data; 53 PC_BJacobiMPIAIJ *bjac = (PC_BJacobiMPIAIJ *) jac->data; 54 Scalar *x_array,*x_true_array, *y_array,*y_true_array; 55 56 /* 57 The VecPlaceArray() is to avoid having to copy the 58 y vector into the bjac->x vector. The reason for 59 the bjac->x vector is that we need a sequential vector 60 for the sequential solve. 61 */ 62 ierr = VecGetArray(x,&x_array); CHKERRQ(ierr); 63 ierr = VecGetArray(y,&y_array); CHKERRQ(ierr); 64 ierr = VecGetArray(bjac->x,&x_true_array); CHKERRQ(ierr); 65 ierr = VecGetArray(bjac->y,&y_true_array); CHKERRQ(ierr); 66 ierr = VecPlaceArray(bjac->x,x_array); CHKERRQ(ierr); 67 ierr = VecPlaceArray(bjac->y,y_array); CHKERRQ(ierr); 68 ierr = SLESSolve(jac->sles[0],bjac->x,bjac->y,&its); CHKERRQ(ierr); 69 ierr = VecPlaceArray(bjac->x,x_true_array); CHKERRQ(ierr); 70 ierr = VecPlaceArray(bjac->y,y_true_array); CHKERRQ(ierr); 71 return 0; 72 } 73 74 int PCSetUp_BJacobiMPIAIJ(PC pc) 75 { 76 PC_BJacobi *jac = (PC_BJacobi *) pc->data; 77 Mat mat = pc->mat, pmat = pc->pmat; 78 Mat_MPIAIJ *pmatin = (Mat_MPIAIJ *) pmat->data; 79 Mat_MPIAIJ *matin = 0; 80 int ierr, m; 81 SLES sles; 82 Vec x,y; 83 PC_BJacobiMPIAIJ *bjac; 84 KSP subksp; 85 PC subpc; 86 MatType type; 87 88 if (jac->use_true_local) { 89 MatGetType(pc->mat,&type,PETSC_NULL); 90 if (type != MATMPIAIJ) SETERRQ(1,"PCSetUp_BJacobiMPIAIJ:Incompatible matrix type."); 91 matin = (Mat_MPIAIJ *) mat->data; 92 } 93 94 /* set default direct solver with no Krylov method */ 95 if (!pc->setupcalled) { 96 ierr = SLESCreate(MPI_COMM_SELF,&sles); CHKERRQ(ierr); 97 PLogObjectParent(pc,sles); 98 ierr = SLESGetKSP(sles,&subksp); CHKERRQ(ierr); 99 ierr = KSPSetType(subksp,KSPPREONLY); CHKERRQ(ierr); 100 ierr = SLESGetPC(sles,&subpc); CHKERRQ(ierr); 101 ierr = PCSetType(subpc,PCLU); CHKERRQ(ierr); 102 ierr = SLESSetOptionsPrefix(sles,"sub_"); CHKERRQ(ierr); 103 ierr = SLESSetFromOptions(sles); CHKERRQ(ierr); 104 /* 105 This is not so good. The only reason we need to generate this vector 106 is so KSP may generate seq vectors for the local solves 107 */ 108 ierr = MatGetSize(pmatin->A,&m,&m); CHKERRQ(ierr); 109 ierr = VecCreateSeq(MPI_COMM_SELF,m,&x); CHKERRQ(ierr); 110 ierr = VecCreateSeq(MPI_COMM_SELF,m,&y); CHKERRQ(ierr); 111 PLogObjectParent(pmat,x); 112 PLogObjectParent(pmat,y); 113 114 pc->destroy = PCDestroy_BJacobiMPIAIJ; 115 pc->apply = PCApply_BJacobiMPIAIJ; 116 pc->setuponblocks = PCSetUpOnBlocks_BJacobiMPIAIJ; 117 118 bjac = (PC_BJacobiMPIAIJ *) PetscMalloc(sizeof(PC_BJacobiMPIAIJ));CHKPTRQ(bjac); 119 PLogObjectMemory(pc,sizeof(PC_BJacobiMPIAIJ)); 120 bjac->x = x; 121 bjac->y = y; 122 123 jac->sles = (SLES*) PetscMalloc( sizeof(SLES) ); CHKPTRQ(jac->sles); 124 jac->sles[0] = sles; 125 jac->data = (void *) bjac; 126 } 127 else { 128 sles = jac->sles[0]; 129 bjac = (PC_BJacobiMPIAIJ *)jac->data; 130 } 131 if (jac->l_true[0] == USE_TRUE_MATRIX) { 132 ierr = SLESSetOperators(sles,matin->A,matin->A,pc->flag); 133 } 134 else if (jac->use_true_local) 135 ierr = SLESSetOperators(sles,matin->A,pmatin->A,pc->flag); 136 else 137 ierr = SLESSetOperators(sles,pmatin->A,pmatin->A,pc->flag); 138 CHKERRQ(ierr); 139 return 0; 140 } 141 142 143