/*@C
PetscSFBcastEnd - end a broadcast operation started with PetscSFBcastBegin()
Collective
Input Arguments:
+ sf - star forest
. unit - data type
- rootdata - buffer to broadcast
Output Arguments:
. leafdata - buffer to update with values from each leaf's respective root
Level: intermediate
.seealso: PetscSFSetGraph(), PetscSFReduceEnd()
@*/
PetscErrorCode PetscSFBcastEnd(PetscSF sf,MPI_Datatype unit,const void *rootdata,void *leafdata)
{
PetscErrorCode ierr;
PetscFunctionBegin;
PetscValidHeaderSpecific(sf,PETSCSF_CLASSID,1);
PetscSFCheckGraphSet(sf,1);
ierr = PetscLogEventBegin(PETSCSF_BcastEnd,sf,0,0,0);CHKERRQ(ierr);
ierr = PetscSFSetUp(sf);CHKERRQ(ierr);
ierr = (*sf->ops->BcastEnd)(sf,unit,rootdata,leafdata);CHKERRQ(ierr);
ierr = PetscLogEventEnd(PETSCSF_BcastEnd,sf,0,0,0);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
/*@C
PetscSFScatterEnd - ends pointwise scatter operation that was started with PetscSFScatterBegin()
Collective
Input Arguments:
+ sf - star forest
. unit - data type
- multirootdata - root buffer to send to each leaf, one unit of data per leaf
Output Argument:
. leafdata - leaf data to be update with personal data from each respective root
Level: intermediate
.seealso: PetscSFComputeDegreeEnd(), PetscSFScatterEnd()
@*/
PetscErrorCode PetscSFScatterEnd(PetscSF sf,MPI_Datatype unit,const void *multirootdata,void *leafdata)
{
PetscErrorCode ierr;
PetscSF multi;
PetscFunctionBegin;
PetscValidHeaderSpecific(sf,PETSCSF_CLASSID,1);
PetscSFCheckGraphSet(sf,1);
ierr = PetscSFSetUp(sf);CHKERRQ(ierr);
ierr = PetscSFGetMultiSF(sf,&multi);CHKERRQ(ierr);
ierr = PetscSFBcastEnd(multi,unit,multirootdata,leafdata);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
/*@C
PetscSFFetchAndOpBegin - begin operation that fetches values from root and updates atomically by applying operation using my leaf value, to be completed with PetscSFFetchAndOpEnd()
Collective
Input Arguments:
+ sf - star forest
. unit - data type
. leafdata - leaf values to use in reduction
- op - operation to use for reduction
Output Arguments:
+ rootdata - root values to be updated, input state is seen by first process to perform an update
- leafupdate - state at each leaf's respective root immediately prior to my atomic update
Level: advanced
Note:
The update is only atomic at the granularity provided by the hardware. Different roots referenced by the same process
might be updated in a different order. Furthermore, if a composite type is used for the unit datatype, atomicity is
not guaranteed across the whole vertex. Therefore, this function is mostly only used with primitive types such as
integers.
.seealso: PetscSFComputeDegreeBegin(), PetscSFReduceBegin(), PetscSFSetGraph()
@*/
PetscErrorCode PetscSFFetchAndOpBegin(PetscSF sf,MPI_Datatype unit,void *rootdata,const void *leafdata,void *leafupdate,MPI_Op op)
{
PetscErrorCode ierr;
PetscFunctionBegin;
PetscValidHeaderSpecific(sf,PETSCSF_CLASSID,1);
PetscSFCheckGraphSet(sf,1);
ierr = PetscLogEventBegin(PETSCSF_FetchAndOpBegin,sf,0,0,0);CHKERRQ(ierr);
ierr = PetscSFSetUp(sf);CHKERRQ(ierr);
ierr = (*sf->ops->FetchAndOpBegin)(sf,unit,rootdata,leafdata,leafupdate,op);CHKERRQ(ierr);
ierr = PetscLogEventEnd(PETSCSF_FetchAndOpBegin,sf,0,0,0);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
/*@C
PetscSFComputeDegreeEnd - complete computation of degree for each root vertex, started with PetscSFComputeDegreeBegin()
Collective
Input Arguments:
. sf - star forest
Output Arguments:
. degree - degree of each root vertex
Level: developer
.seealso:
@*/
PetscErrorCode PetscSFComputeDegreeEnd(PetscSF sf,const PetscInt **degree)
{
PetscErrorCode ierr;
PetscFunctionBegin;
PetscValidHeaderSpecific(sf,PETSCSF_CLASSID,1);
PetscSFCheckGraphSet(sf,1);
if (!sf->degreeknown) {
ierr = PetscSFReduceEnd(sf,MPIU_INT,sf->degreetmp,sf->degree,MPI_SUM);CHKERRQ(ierr);
ierr = PetscFree(sf->degreetmp);CHKERRQ(ierr);
sf->degreeknown = PETSC_TRUE;
}
*degree = sf->degree;
PetscFunctionReturn(0);
}
/*@C
PetscSFComputeDegreeBegin - begin computation of degree for each root vertex, to be completed with PetscSFComputeDegreeEnd()
Collective
Input Arguments:
. sf - star forest
Output Arguments:
. degree - degree of each root vertex
Level: advanced
.seealso: PetscSFGatherBegin()
@*/
PetscErrorCode PetscSFComputeDegreeBegin(PetscSF sf,const PetscInt **degree)
{
PetscErrorCode ierr;
PetscFunctionBegin;
PetscValidHeaderSpecific(sf,PETSCSF_CLASSID,1);
PetscSFCheckGraphSet(sf,1);
PetscValidPointer(degree,2);
if (!sf->degree) {
PetscInt i;
ierr = PetscMalloc1(sf->nroots,&sf->degree);CHKERRQ(ierr);
ierr = PetscMalloc1(sf->nleaves,&sf->degreetmp);CHKERRQ(ierr);
for (i=0; i<sf->nroots; i++) sf->degree[i] = 0;
for (i=0; i<sf->nleaves; i++) sf->degreetmp[i] = 1;
ierr = PetscSFReduceBegin(sf,MPIU_INT,sf->degreetmp,sf->degree,MPIU_SUM);CHKERRQ(ierr);
}
*degree = NULL;
PetscFunctionReturn(0);
}
/*@C
PetscSFComputeDegreeBegin - begin computation of degree for each root vertex, to be completed with PetscSFComputeDegreeEnd()
Collective
Input Arguments:
. sf - star forest
Output Arguments:
. degree - degree of each root vertex
Level: advanced
.seealso: PetscSFGatherBegin()
@*/
PetscErrorCode PetscSFComputeDegreeBegin(PetscSF sf,const PetscInt **degree)
{
PetscErrorCode ierr;
PetscFunctionBegin;
PetscValidHeaderSpecific(sf,PETSCSF_CLASSID,1);
PetscSFCheckGraphSet(sf,1);
PetscValidPointer(degree,2);
if (!sf->degreeknown) {
PetscInt i,maxlocal;
if (sf->degree) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Calls to PetscSFComputeDegreeBegin() cannot be nested.");
for (i=0,maxlocal=0; i<sf->nleaves; i++) maxlocal = PetscMax(maxlocal,(sf->mine ? sf->mine[i] : i)+1);
ierr = PetscMalloc1(sf->nroots,&sf->degree);CHKERRQ(ierr);
ierr = PetscMalloc1(maxlocal,&sf->degreetmp);CHKERRQ(ierr);
for (i=0; i<sf->nroots; i++) sf->degree[i] = 0;
for (i=0; i<maxlocal; i++) sf->degreetmp[i] = 1;
ierr = PetscSFReduceBegin(sf,MPIU_INT,sf->degreetmp,sf->degree,MPI_SUM);CHKERRQ(ierr);
}
*degree = NULL;
PetscFunctionReturn(0);
}
