Exemplo n.º 1
0
Arquivo: pbvec.c Projeto: petsc/petsc
static PetscErrorCode VecSetOption_MPI(Vec V,VecOption op,PetscBool flag)
{
  Vec_MPI        *v = (Vec_MPI*)V->data;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  switch (op) {
  case VEC_IGNORE_OFF_PROC_ENTRIES: V->stash.donotstash = flag;
    break;
  case VEC_IGNORE_NEGATIVE_INDICES: V->stash.ignorenegidx = flag;
    break;
  case VEC_SUBSET_OFF_PROC_ENTRIES:
    v->assembly_subset = flag; /* See the same logic in MatAssembly wrt MAT_SUBSET_OFF_PROC_ENTRIES */
    if (!v->assembly_subset) { /* User indicates "do not reuse the communication pattern" */
      ierr = VecAssemblyReset_MPI(V);CHKERRQ(ierr); /* Reset existing pattern to free memory */
      v->first_assembly_done = PETSC_FALSE; /* Mark the first assembly is not done */
    }
    break;
  }

  PetscFunctionReturn(0);
}
Exemplo n.º 2
0
static PetscErrorCode VecAssemblyEnd_MPI_BTS(Vec X)
{
  Vec_MPI *x = (Vec_MPI*)X->data;
  PetscInt bs = X->map->bs;
  PetscMPIInt npending,*some_indices,r;
  MPI_Status  *some_statuses;
  PetscScalar *xarray;
  PetscErrorCode ierr;
  VecAssemblyFrame *frame;

  PetscFunctionBegin;
  if (X->stash.donotstash) {
    X->stash.insertmode = NOT_SET_VALUES;
    X->bstash.insertmode = NOT_SET_VALUES;
    PetscFunctionReturn(0);
  }

  ierr = VecGetArray(X,&xarray);CHKERRQ(ierr);
  ierr = PetscSegBufferExtractInPlace(x->segrecvframe,&frame);CHKERRQ(ierr);
  ierr = PetscMalloc2(4*x->nrecvranks,&some_indices,x->use_status?4*x->nrecvranks:0,&some_statuses);CHKERRQ(ierr);
  for (r=0,npending=0; r<x->nrecvranks; r++) npending += frame[r].pendings + frame[r].pendingb;
  while (npending>0) {
    PetscMPIInt ndone,ii;
    /* Filling MPI_Status fields requires some resources from the MPI library.  We skip it on the first assembly, or
     * when VEC_SUBSET_OFF_PROC_ENTRIES has not been set, because we could exchange exact sizes in the initial
     * rendezvous.  When the rendezvous is elided, however, we use MPI_Status to get actual message lengths, so that
     * subsequent assembly can set a proper subset of the values. */
    ierr = MPI_Waitsome(4*x->nrecvranks,x->recvreqs,&ndone,some_indices,x->use_status?some_statuses:MPI_STATUSES_IGNORE);CHKERRQ(ierr);
    for (ii=0; ii<ndone; ii++) {
      PetscInt i = some_indices[ii]/4,j,k;
      InsertMode imode = (InsertMode)x->recvhdr[i].insertmode;
      PetscInt *recvint;
      PetscScalar *recvscalar;
      PetscBool intmsg = (PetscBool)(some_indices[ii]%2 == 0);
      PetscBool blockmsg = (PetscBool)((some_indices[ii]%4)/2 == 1);
      npending--;
      if (!blockmsg) { /* Scalar stash */
        PetscMPIInt count;
        if (--frame[i].pendings > 0) continue;
        if (x->use_status) {
          ierr = MPI_Get_count(&some_statuses[ii],intmsg ? MPIU_INT : MPIU_SCALAR,&count);CHKERRQ(ierr);
        } else count = x->recvhdr[i].count;
        for (j=0,recvint=frame[i].ints,recvscalar=frame[i].scalars; j<count; j++,recvint++) {
          PetscInt loc = *recvint - X->map->rstart;
          if (*recvint < X->map->rstart || X->map->rend <= *recvint) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Received vector entry %D out of local range [%D,%D)]",*recvint,X->map->rstart,X->map->rend);
          switch (imode) {
          case ADD_VALUES:
            xarray[loc] += *recvscalar++;
            break;
          case INSERT_VALUES:
            xarray[loc] = *recvscalar++;
            break;
          default: SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"Insert mode not supported 0x%x",imode);
          }
        }
      } else {                  /* Block stash */
        PetscMPIInt count;
        if (--frame[i].pendingb > 0) continue;
        if (x->use_status) {
          ierr = MPI_Get_count(&some_statuses[ii],intmsg ? MPIU_INT : MPIU_SCALAR,&count);CHKERRQ(ierr);
          if (!intmsg) count /= bs; /* Convert from number of scalars to number of blocks */
        } else count = x->recvhdr[i].bcount;
        for (j=0,recvint=frame[i].intb,recvscalar=frame[i].scalarb; j<count; j++,recvint++) {
          PetscInt loc = (*recvint)*bs - X->map->rstart;
          switch (imode) {
          case ADD_VALUES:
            for (k=loc; k<loc+bs; k++) xarray[k] += *recvscalar++;
            break;
          case INSERT_VALUES:
            for (k=loc; k<loc+bs; k++) xarray[k] = *recvscalar++;
            break;
          default: SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"Insert mode not supported 0x%x",imode);
          }
        }
      }
    }
  }
  ierr = VecRestoreArray(X,&xarray);CHKERRQ(ierr);
  ierr = MPI_Waitall(4*x->nsendranks,x->sendreqs,MPI_STATUSES_IGNORE);CHKERRQ(ierr);
  ierr = PetscFree2(some_indices,some_statuses);CHKERRQ(ierr);
  if (x->assembly_subset) {
    void *dummy;                /* reset segbuffers */
    ierr = PetscSegBufferExtractInPlace(x->segrecvint,&dummy);CHKERRQ(ierr);
    ierr = PetscSegBufferExtractInPlace(x->segrecvscalar,&dummy);CHKERRQ(ierr);
  } else {
    ierr = VecAssemblyReset_MPI(X);CHKERRQ(ierr);
  }

  X->stash.insertmode = NOT_SET_VALUES;
  X->bstash.insertmode = NOT_SET_VALUES;
  ierr = VecStashScatterEnd_Private(&X->stash);CHKERRQ(ierr);
  ierr = VecStashScatterEnd_Private(&X->bstash);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}