Date: 2026-05-01T06:11:53+00:00

Actual source code: chowiluviennacl.cxx

      1: /*
      2:    Include files needed for the ViennaCL Chow-Patel parallel ILU preconditioner:
      3:      pcimpl.h - private include file intended for use by all preconditioners
      4: */
      5: #define PETSC_SKIP_IMMINTRIN_H_CUDAWORKAROUND 1

      7: #include <petsc/private/pcimpl.h>
      8: #include <../src/mat/impls/aij/seq/aij.h>
      9: #include <../src/vec/vec/impls/dvecimpl.h>
     10: #include <../src/mat/impls/aij/seq/seqviennacl/viennaclmatimpl.h>
     11: #include <../src/vec/vec/impls/seq/seqviennacl/viennaclvecimpl.h>
     12: #include <viennacl/linalg/detail/ilu/chow_patel_ilu.hpp>

     14: /*
     15:    Private context (data structure) for the CHOWILUVIENNACL preconditioner.
     16: */
     17: typedef struct {
     18:   viennacl::linalg::chow_patel_ilu_precond<viennacl::compressed_matrix<PetscScalar>> *CHOWILUVIENNACL;
     19: } PC_CHOWILUVIENNACL;

     21: /*
     22:    PCSetUp_CHOWILUVIENNACL - Prepares for the use of the CHOWILUVIENNACL preconditioner
     23:                              by setting data structures and options.

     25:    Input Parameter:
     26: .  pc - the preconditioner context

     28:    Application Interface Routine: PCSetUp()

     30:    Note:
     31:    The interface routine PCSetUp() is not usually called directly by
     32:    the user, but instead is called by PCApply() if necessary.
     33: */
     34: static PetscErrorCode PCSetUp_CHOWILUVIENNACL(PC pc)
     35: {
     36:   PC_CHOWILUVIENNACL *ilu = (PC_CHOWILUVIENNACL *)pc->data;
     37:   PetscBool           flg = PETSC_FALSE;
     38:   Mat_SeqAIJViennaCL *gpustruct;

     40:   PetscFunctionBegin;
     41:   PetscCall(PetscObjectTypeCompare((PetscObject)pc->pmat, MATSEQAIJVIENNACL, &flg));
     42:   PetscCheck(flg, PetscObjectComm((PetscObject)pc), PETSC_ERR_SUP, "Currently only handles ViennaCL matrices");
     43:   if (pc->setupcalled) {
     44:     try {
     45:       delete ilu->CHOWILUVIENNACL;
     46:     } catch (char *ex) {
     47:       SETERRQ(PETSC_COMM_SELF, PETSC_ERR_LIB, "ViennaCL error: %s", ex);
     48:     }
     49:   }
     50:   try {
     51: #if defined(PETSC_USE_COMPLEX)
     52:     gpustruct = NULL;
     53:     SETERRQ(PetscObjectComm((PetscObject)pc), PETSC_ERR_SUP, "No support for complex arithmetic in CHOWILUVIENNACL preconditioner");
     54: #else
     55:     PetscCall(MatViennaCLCopyToGPU(pc->pmat));
     56:     gpustruct = (Mat_SeqAIJViennaCL *)pc->pmat->spptr;

     58:     viennacl::linalg::chow_patel_tag ilu_tag;
     59:     ViennaCLAIJMatrix               *mat = (ViennaCLAIJMatrix *)gpustruct->mat;
     60:     ilu->CHOWILUVIENNACL                 = new viennacl::linalg::chow_patel_ilu_precond<viennacl::compressed_matrix<PetscScalar>>(*mat, ilu_tag);
     61: #endif
     62:   } catch (char *ex) {
     63:     SETERRQ(PETSC_COMM_SELF, PETSC_ERR_LIB, "ViennaCL error: %s", ex);
     64:   }
     65:   PetscFunctionReturn(PETSC_SUCCESS);
     66: }

     68: /*
     69:    PCApply_CHOWILUVIENNACL - Applies the CHOWILUVIENNACL preconditioner to a vector.

     71:    Input Parameters:
     72: .  pc - the preconditioner context
     73: .  x - input vector

     75:    Output Parameter:
     76: .  y - output vector

     78:    Application Interface Routine: PCApply()
     79:  */
     80: static PetscErrorCode PCApply_CHOWILUVIENNACL(PC pc, Vec x, Vec y)
     81: {
     82:   PC_CHOWILUVIENNACL                  *ilu = (PC_CHOWILUVIENNACL *)pc->data;
     83:   PetscBool                            flg1, flg2;
     84:   viennacl::vector<PetscScalar> const *xarray = NULL;
     85:   viennacl::vector<PetscScalar>       *yarray = NULL;

     87:   PetscFunctionBegin;
     88:   /*how to apply a certain fixed number of iterations?*/
     89:   PetscCall(PetscObjectTypeCompare((PetscObject)x, VECSEQVIENNACL, &flg1));
     90:   PetscCall(PetscObjectTypeCompare((PetscObject)y, VECSEQVIENNACL, &flg2));
     91:   PetscCheck(flg1 && flg2, PetscObjectComm((PetscObject)pc), PETSC_ERR_SUP, "Currently only handles ViennaCL vectors");
     92:   if (!ilu->CHOWILUVIENNACL) PetscCall(PCSetUp_CHOWILUVIENNACL(pc));
     93:   PetscCall(VecSet(y, 0.0));
     94:   PetscCall(VecViennaCLGetArrayRead(x, &xarray));
     95:   PetscCall(VecViennaCLGetArrayWrite(y, &yarray));
     96:   try {
     97: #if defined(PETSC_USE_COMPLEX)

     99: #else
    100:     *yarray = *xarray;
    101:     ilu->CHOWILUVIENNACL->apply(*yarray);
    102: #endif
    103:   } catch (char *ex) {
    104:     SETERRQ(PETSC_COMM_SELF, PETSC_ERR_LIB, "ViennaCL error: %s", ex);
    105:   }
    106:   PetscCall(VecViennaCLRestoreArrayRead(x, &xarray));
    107:   PetscCall(VecViennaCLRestoreArrayWrite(y, &yarray));
    108:   PetscCall(PetscObjectStateIncrease((PetscObject)y));
    109:   PetscFunctionReturn(PETSC_SUCCESS);
    110: }

    112: /*
    113:    PCDestroy_CHOWILUVIENNACL - Destroys the private context for the CHOWILUVIENNACL preconditioner
    114:    that was created with PCCreate_CHOWILUVIENNACL().

    116:    Input Parameter:
    117: .  pc - the preconditioner context

    119:    Application Interface Routine: PCDestroy()
    120: */
    121: static PetscErrorCode PCDestroy_CHOWILUVIENNACL(PC pc)
    122: {
    123:   PC_CHOWILUVIENNACL *ilu = (PC_CHOWILUVIENNACL *)pc->data;

    125:   PetscFunctionBegin;
    126:   if (ilu->CHOWILUVIENNACL) {
    127:     try {
    128:       delete ilu->CHOWILUVIENNACL;
    129:     } catch (char *ex) {
    130:       SETERRQ(PETSC_COMM_SELF, PETSC_ERR_LIB, "ViennaCL error: %s", ex);
    131:     }
    132:   }

    134:   /*
    135:       Free the private data structure that was hanging off the PC
    136:   */
    137:   PetscCall(PetscFree(pc->data));
    138:   PetscFunctionReturn(PETSC_SUCCESS);
    139: }

    141: static PetscErrorCode PCSetFromOptions_CHOWILUVIENNACL(PC pc, PetscOptionItems PetscOptionsObject)
    142: {
    143:   PetscFunctionBegin;
    144:   PetscOptionsHeadBegin(PetscOptionsObject, "CHOWILUVIENNACL options");
    145:   PetscOptionsHeadEnd();
    146:   PetscFunctionReturn(PETSC_SUCCESS);
    147: }

    149: PETSC_EXTERN PetscErrorCode PCCreate_CHOWILUVIENNACL(PC pc)
    150: {
    151:   PC_CHOWILUVIENNACL *ilu;

    153:   PetscFunctionBegin;
    154:   /*
    155:      Creates the private data structure for this preconditioner and
    156:      attach it to the PC object.
    157:   */
    158:   PetscCall(PetscNew(&ilu));
    159:   pc->data = (void *)ilu;

    161:   /*
    162:      Initialize the pointer to zero
    163:      Initialize number of v-cycles to default (1)
    164:   */
    165:   ilu->CHOWILUVIENNACL = 0;

    167:   /*
    168:       Set the pointers for the functions that are provided above.
    169:       Now when the user-level routines (such as PCApply(), PCDestroy(), etc.)
    170:       are called, they will automatically call these functions.  Note we
    171:       choose not to provide a couple of these functions since they are
    172:       not needed.
    173:   */
    174:   pc->ops->apply               = PCApply_CHOWILUVIENNACL;
    175:   pc->ops->applytranspose      = 0;
    176:   pc->ops->setup               = PCSetUp_CHOWILUVIENNACL;
    177:   pc->ops->destroy             = PCDestroy_CHOWILUVIENNACL;
    178:   pc->ops->setfromoptions      = PCSetFromOptions_CHOWILUVIENNACL;
    179:   pc->ops->view                = 0;
    180:   pc->ops->applyrichardson     = 0;
    181:   pc->ops->applysymmetricleft  = 0;
    182:   pc->ops->applysymmetricright = 0;
    183:   PetscFunctionReturn(PETSC_SUCCESS);
    184: }