static PetscErrorCode PetscCommBuildTwoSided_Ibarrier(MPI_Comm comm,PetscMPIInt count,MPI_Datatype dtype,PetscMPIInt nto,const PetscMPIInt *toranks,const void *todata,PetscMPIInt *nfrom,PetscMPIInt **fromranks,void *fromdata)
{
PetscErrorCode ierr;
PetscMPIInt nrecvs,tag,done,i;
MPI_Aint lb,unitbytes;
char *tdata;
MPI_Request *sendreqs,barrier;
PetscSegBuffer segrank,segdata;
PetscFunctionBegin;
ierr = PetscCommDuplicate(comm,&comm,&tag);CHKERRQ(ierr);
ierr = MPI_Type_get_extent(dtype,&lb,&unitbytes);CHKERRQ(ierr);
if (lb != 0) SETERRQ1(comm,PETSC_ERR_SUP,"Datatype with nonzero lower bound %ld\n",(long)lb);
tdata = (char*)todata;
ierr = PetscMalloc1(nto,&sendreqs);CHKERRQ(ierr);
for (i=0; i<nto; i++) {
ierr = MPI_Issend((void*)(tdata+count*unitbytes*i),count,dtype,toranks[i],tag,comm,sendreqs+i);CHKERRQ(ierr);
}
ierr = PetscSegBufferCreate(sizeof(PetscMPIInt),4,&segrank);CHKERRQ(ierr);
ierr = PetscSegBufferCreate(unitbytes,4*count,&segdata);CHKERRQ(ierr);
nrecvs = 0;
barrier = MPI_REQUEST_NULL;
for (done=0; !done; ) {
PetscMPIInt flag;
MPI_Status status;
ierr = MPI_Iprobe(MPI_ANY_SOURCE,tag,comm,&flag,&status);CHKERRQ(ierr);
if (flag) { /* incoming message */
PetscMPIInt *recvrank;
void *buf;
ierr = PetscSegBufferGet(segrank,1,&recvrank);CHKERRQ(ierr);
ierr = PetscSegBufferGet(segdata,count,&buf);CHKERRQ(ierr);
*recvrank = status.MPI_SOURCE;
ierr = MPI_Recv(buf,count,dtype,status.MPI_SOURCE,tag,comm,MPI_STATUS_IGNORE);CHKERRQ(ierr);
nrecvs++;
}
if (barrier == MPI_REQUEST_NULL) {
PetscMPIInt sent,nsends;
ierr = PetscMPIIntCast(nto,&nsends);CHKERRQ(ierr);
ierr = MPI_Testall(nsends,sendreqs,&sent,MPI_STATUSES_IGNORE);CHKERRQ(ierr);
if (sent) {
#if defined(PETSC_HAVE_MPI_IBARRIER)
ierr = MPI_Ibarrier(comm,&barrier);CHKERRQ(ierr);
#elif defined(PETSC_HAVE_MPIX_IBARRIER)
ierr = MPIX_Ibarrier(comm,&barrier);CHKERRQ(ierr);
#endif
ierr = PetscFree(sendreqs);CHKERRQ(ierr);
}
} else {
ierr = MPI_Test(&barrier,&done,MPI_STATUS_IGNORE);CHKERRQ(ierr);
}
}
*nfrom = nrecvs;
ierr = PetscSegBufferExtractAlloc(segrank,fromranks);CHKERRQ(ierr);
ierr = PetscSegBufferDestroy(&segrank);CHKERRQ(ierr);
ierr = PetscSegBufferExtractAlloc(segdata,fromdata);CHKERRQ(ierr);
ierr = PetscSegBufferDestroy(&segdata);CHKERRQ(ierr);
ierr = PetscCommDestroy(&comm);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
static PetscErrorCode PetscCommBuildTwoSidedFReq_Ibarrier(MPI_Comm comm,PetscMPIInt count,MPI_Datatype dtype,PetscMPIInt nto,const PetscMPIInt *toranks,const void *todata,
PetscMPIInt *nfrom,PetscMPIInt **fromranks,void *fromdata,PetscMPIInt ntags,MPI_Request **toreqs,MPI_Request **fromreqs,
PetscErrorCode (*send)(MPI_Comm,const PetscMPIInt[],PetscMPIInt,PetscMPIInt,void*,MPI_Request[],void*),
PetscErrorCode (*recv)(MPI_Comm,const PetscMPIInt[],PetscMPIInt,void*,MPI_Request[],void*),void *ctx)
{
PetscErrorCode ierr;
PetscMPIInt nrecvs,tag,*tags,done,i;
MPI_Aint lb,unitbytes;
char *tdata;
MPI_Request *sendreqs,*usendreqs,*req,barrier;
PetscSegBuffer segrank,segdata,segreq;
PetscBool barrier_started;
PetscFunctionBegin;
ierr = PetscCommDuplicate(comm,&comm,&tag);CHKERRQ(ierr);
ierr = PetscMalloc1(ntags,&tags);CHKERRQ(ierr);
for (i=0; i<ntags; i++) {
ierr = PetscCommGetNewTag(comm,&tags[i]);CHKERRQ(ierr);
}
ierr = MPI_Type_get_extent(dtype,&lb,&unitbytes);CHKERRQ(ierr);
if (lb != 0) SETERRQ1(comm,PETSC_ERR_SUP,"Datatype with nonzero lower bound %ld\n",(long)lb);
tdata = (char*)todata;
ierr = PetscMalloc1(nto,&sendreqs);CHKERRQ(ierr);
ierr = PetscMalloc1(nto*ntags,&usendreqs);CHKERRQ(ierr);
/* Post synchronous sends */
for (i=0; i<nto; i++) {
ierr = MPI_Issend((void*)(tdata+count*unitbytes*i),count,dtype,toranks[i],tag,comm,sendreqs+i);CHKERRQ(ierr);
}
/* Post actual payloads. These are typically larger messages. Hopefully sending these later does not slow down the
* synchronous messages above. */
for (i=0; i<nto; i++) {
PetscMPIInt k;
for (k=0; k<ntags; k++) usendreqs[i*ntags+k] = MPI_REQUEST_NULL;
ierr = (*send)(comm,tags,i,toranks[i],tdata+count*unitbytes*i,usendreqs+i*ntags,ctx);CHKERRQ(ierr);
}
ierr = PetscSegBufferCreate(sizeof(PetscMPIInt),4,&segrank);CHKERRQ(ierr);
ierr = PetscSegBufferCreate(unitbytes,4*count,&segdata);CHKERRQ(ierr);
ierr = PetscSegBufferCreate(sizeof(MPI_Request),4,&segreq);CHKERRQ(ierr);
nrecvs = 0;
barrier = MPI_REQUEST_NULL;
/* MPICH-3.2 sometimes does not create a request in some "optimized" cases. This is arguably a standard violation,
* but we need to work around it. */
barrier_started = PETSC_FALSE;
for (done=0; !done; ) {
PetscMPIInt flag;
MPI_Status status;
ierr = MPI_Iprobe(MPI_ANY_SOURCE,tag,comm,&flag,&status);CHKERRQ(ierr);
if (flag) { /* incoming message */
PetscMPIInt *recvrank,k;
void *buf;
ierr = PetscSegBufferGet(segrank,1,&recvrank);CHKERRQ(ierr);
ierr = PetscSegBufferGet(segdata,count,&buf);CHKERRQ(ierr);
*recvrank = status.MPI_SOURCE;
ierr = MPI_Recv(buf,count,dtype,status.MPI_SOURCE,tag,comm,MPI_STATUS_IGNORE);CHKERRQ(ierr);
ierr = PetscSegBufferGet(segreq,ntags,&req);CHKERRQ(ierr);
for (k=0; k<ntags; k++) req[k] = MPI_REQUEST_NULL;
ierr = (*recv)(comm,tags,status.MPI_SOURCE,buf,req,ctx);CHKERRQ(ierr);
nrecvs++;
}
if (!barrier_started) {
PetscMPIInt sent,nsends;
ierr = PetscMPIIntCast(nto,&nsends);CHKERRQ(ierr);
ierr = MPI_Testall(nsends,sendreqs,&sent,MPI_STATUSES_IGNORE);CHKERRQ(ierr);
if (sent) {
#if defined(PETSC_HAVE_MPI_IBARRIER)
ierr = MPI_Ibarrier(comm,&barrier);CHKERRQ(ierr);
#elif defined(PETSC_HAVE_MPIX_IBARRIER)
ierr = MPIX_Ibarrier(comm,&barrier);CHKERRQ(ierr);
#endif
barrier_started = PETSC_TRUE;
}
} else {
ierr = MPI_Test(&barrier,&done,MPI_STATUS_IGNORE);CHKERRQ(ierr);
}
}
*nfrom = nrecvs;
ierr = PetscSegBufferExtractAlloc(segrank,fromranks);CHKERRQ(ierr);
ierr = PetscSegBufferDestroy(&segrank);CHKERRQ(ierr);
ierr = PetscSegBufferExtractAlloc(segdata,fromdata);CHKERRQ(ierr);
ierr = PetscSegBufferDestroy(&segdata);CHKERRQ(ierr);
*toreqs = usendreqs;
ierr = PetscSegBufferExtractAlloc(segreq,fromreqs);CHKERRQ(ierr);
ierr = PetscSegBufferDestroy(&segreq);CHKERRQ(ierr);
ierr = PetscFree(sendreqs);CHKERRQ(ierr);
ierr = PetscFree(tags);CHKERRQ(ierr);
ierr = PetscCommDestroy(&comm);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
