Date: 2022-03-04T17:38:55+00:00

Actual source code: saviennacl.cxx

      2: /*  -------------------------------------------------------------------- */

      4: /*
      5:    Include files needed for the ViennaCL Smoothed Aggregation preconditioner:
      6:      pcimpl.h - private include file intended for use by all preconditioners
      7: */
      8: #define PETSC_SKIP_SPINLOCK
      9: #define PETSC_SKIP_IMMINTRIN_H_CUDAWORKAROUND 1
     10: #include <petsc/private/pcimpl.h>
     11: #include <../src/mat/impls/aij/seq/aij.h>
     12: #include <../src/vec/vec/impls/dvecimpl.h>
     13: #include <../src/mat/impls/aij/seq/seqviennacl/viennaclmatimpl.h>
     14: #include <../src/vec/vec/impls/seq/seqviennacl/viennaclvecimpl.h>
     15: #include <viennacl/linalg/amg.hpp>

     17: /*
     18:    Private context (data structure) for the SAVIENNACL preconditioner.
     19: */
     20: typedef struct {
     21:   viennacl::linalg::amg_precond<viennacl::compressed_matrix<PetscScalar> > *SAVIENNACL;
     22: } PC_SAVIENNACL;

     24: /* -------------------------------------------------------------------------- */
     25: /*
     26:    PCSetUp_SAVIENNACL - Prepares for the use of the SAVIENNACL preconditioner
     27:                         by setting data structures and options.

     29:    Input Parameter:
     30: .  pc - the preconditioner context

     32:    Application Interface Routine: PCSetUp()

     34:    Notes:
     35:    The interface routine PCSetUp() is not usually called directly by
     36:    the user, but instead is called by PCApply() if necessary.
     37: */
     38: static PetscErrorCode PCSetUp_SAVIENNACL(PC pc)
     39: {
     40:   PC_SAVIENNACL      *sa = (PC_SAVIENNACL*)pc->data;
     41:   PetscBool          flg = PETSC_FALSE;
     42:   PetscErrorCode     ierr;
     43:   Mat_SeqAIJViennaCL *gpustruct;

     46:   PetscObjectTypeCompare((PetscObject)pc->pmat,MATSEQAIJVIENNACL,&flg);
     47:   if (!flg) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"Currently only handles ViennaCL matrices");
     48:   if (pc->setupcalled != 0) {
     49:     try {
     50:       delete sa->SAVIENNACL;
     51:     } catch(char *ex) {
     52:       SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"ViennaCL error: %s", ex);
     53:     }
     54:   }
     55:   try {
     56: #if defined(PETSC_USE_COMPLEX)
     57:     gpustruct = NULL;
     58:     SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"No support for complex arithmetic in SAVIENNACL preconditioner");
     59: #else
     60:     MatViennaCLCopyToGPU(pc->pmat);
     61:     gpustruct = (Mat_SeqAIJViennaCL*)(pc->pmat->spptr);

     63:     viennacl::linalg::amg_tag amg_tag_sa_pmis;
     64:     amg_tag_sa_pmis.set_coarsening_method(viennacl::linalg::AMG_COARSENING_METHOD_MIS2_AGGREGATION);
     65:     amg_tag_sa_pmis.set_interpolation_method(viennacl::linalg::AMG_INTERPOLATION_METHOD_SMOOTHED_AGGREGATION);
     66:     ViennaCLAIJMatrix *mat = (ViennaCLAIJMatrix*)gpustruct->mat;
     67:     sa->SAVIENNACL = new viennacl::linalg::amg_precond<viennacl::compressed_matrix<PetscScalar> >(*mat, amg_tag_sa_pmis);
     68:     sa->SAVIENNACL->setup();
     69: #endif
     70:   } catch(char *ex) {
     71:     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"ViennaCL error: %s", ex);
     72:   }
     73:   return(0);
     74: }

     76: /* -------------------------------------------------------------------------- */
     77: /*
     78:    PCApply_SAVIENNACL - Applies the SAVIENNACL preconditioner to a vector.

     80:    Input Parameters:
     81: .  pc - the preconditioner context
     82: .  x - input vector

     84:    Output Parameter:
     85: .  y - output vector

     87:    Application Interface Routine: PCApply()
     88:  */
     89: static PetscErrorCode PCApply_SAVIENNACL(PC pc,Vec x,Vec y)
     90: {
     91:   PC_SAVIENNACL                 *sac = (PC_SAVIENNACL*)pc->data;
     92:   PetscErrorCode                ierr;
     93:   PetscBool                     flg1,flg2;
     94:   viennacl::vector<PetscScalar> const *xarray=NULL;
     95:   viennacl::vector<PetscScalar> *yarray=NULL;

     98:   /*how to apply a certain fixed number of iterations?*/
     99:   PetscObjectTypeCompare((PetscObject)x,VECSEQVIENNACL,&flg1);
    100:   PetscObjectTypeCompare((PetscObject)y,VECSEQVIENNACL,&flg2);
    101:   if (!(flg1 && flg2)) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP, "Currently only handles ViennaCL vectors");
    102:   if (!sac->SAVIENNACL) {
    103:     PCSetUp_SAVIENNACL(pc);
    104:   }
    105:   VecViennaCLGetArrayRead(x,&xarray);
    106:   VecViennaCLGetArrayWrite(y,&yarray);
    107:   try {
    108: #if !defined(PETSC_USE_COMPLEX)
    109:     *yarray = *xarray;
    110:     sac->SAVIENNACL->apply(*yarray);
    111: #endif
    112:   } catch(char * ex) {
    113:     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"ViennaCL error: %s", ex);
    114:   }
    115:   VecViennaCLRestoreArrayRead(x,&xarray);
    116:   VecViennaCLRestoreArrayWrite(y,&yarray);
    117:   PetscObjectStateIncrease((PetscObject)y);
    118:   return(0);
    119: }
    120: /* -------------------------------------------------------------------------- */
    121: /*
    122:    PCDestroy_SAVIENNACL - Destroys the private context for the SAVIENNACL preconditioner
    123:    that was created with PCCreate_SAVIENNACL().

    125:    Input Parameter:
    126: .  pc - the preconditioner context

    128:    Application Interface Routine: PCDestroy()
    129: */
    130: static PetscErrorCode PCDestroy_SAVIENNACL(PC pc)
    131: {
    132:   PC_SAVIENNACL  *sac = (PC_SAVIENNACL*)pc->data;

    136:   if (sac->SAVIENNACL) {
    137:     try {
    138:       delete sac->SAVIENNACL;
    139:     } catch(char * ex) {
    140:       SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"ViennaCL error: %s", ex);
    141:     }
    142:   }

    144:   /*
    145:       Free the private data structure that was hanging off the PC
    146:   */
    147:   PetscFree(pc->data);
    148:   return(0);
    149: }

    151: static PetscErrorCode PCSetFromOptions_SAVIENNACL(PetscOptionItems *PetscOptionsObject,PC pc)
    152: {

    156:   PetscOptionsHead(PetscOptionsObject,"SAVIENNACL options");
    157:   PetscOptionsTail();
    158:   return(0);
    159: }

    161: /* -------------------------------------------------------------------------- */

    163: /*MC
    164:      PCSAViennaCL  - A smoothed agglomeration algorithm that can be used via the CUDA, OpenCL, and OpenMP backends of ViennaCL

    166:    Level: advanced

    168: .seealso:  PCCreate(), PCSetType(), PCType (for list of available types), PC

    170: M*/

    172: PETSC_EXTERN PetscErrorCode PCCreate_SAVIENNACL(PC pc)
    173: {
    174:   PC_SAVIENNACL  *sac;

    178:   /*
    179:      Creates the private data structure for this preconditioner and
    180:      attach it to the PC object.
    181:   */
    182:   PetscNewLog(pc,&sac);
    183:   pc->data = (void*)sac;

    185:   /*
    186:      Initialize the pointer to zero
    187:      Initialize number of v-cycles to default (1)
    188:   */
    189:   sac->SAVIENNACL = 0;

    191:   /*
    192:       Set the pointers for the functions that are provided above.
    193:       Now when the user-level routines (such as PCApply(), PCDestroy(), etc.)
    194:       are called, they will automatically call these functions.  Note we
    195:       choose not to provide a couple of these functions since they are
    196:       not needed.
    197:   */
    198:   pc->ops->apply               = PCApply_SAVIENNACL;
    199:   pc->ops->applytranspose      = 0;
    200:   pc->ops->setup               = PCSetUp_SAVIENNACL;
    201:   pc->ops->destroy             = PCDestroy_SAVIENNACL;
    202:   pc->ops->setfromoptions      = PCSetFromOptions_SAVIENNACL;
    203:   pc->ops->view                = 0;
    204:   pc->ops->applyrichardson     = 0;
    205:   pc->ops->applysymmetricleft  = 0;
    206:   pc->ops->applysymmetricright = 0;
    207:   return(0);
    208: }