1 #include <../src/vec/is/sf/impls/basic/allgatherv/sfallgatherv.h> 2 3 /* Reuse the type. The difference is some fields (i.e., displs, recvcounts) are not used in Allgather on rank != 0, which is not a big deal */ 4 typedef PetscSF_Allgatherv PetscSF_Allgather; 5 6 PETSC_INTERN PetscErrorCode PetscSFBcastBegin_Gather(PetscSF, MPI_Datatype, PetscMemType, const void *, PetscMemType, void *, MPI_Op); 7 8 PetscErrorCode PetscSFSetUp_Allgather(PetscSF sf) { 9 PetscInt i; 10 PetscSF_Allgather *dat = (PetscSF_Allgather *)sf->data; 11 12 PetscFunctionBegin; 13 for (i = PETSCSF_LOCAL; i <= PETSCSF_REMOTE; i++) { 14 sf->leafbuflen[i] = 0; 15 sf->leafstart[i] = 0; 16 sf->leafcontig[i] = PETSC_TRUE; 17 sf->leafdups[i] = PETSC_FALSE; 18 dat->rootbuflen[i] = 0; 19 dat->rootstart[i] = 0; 20 dat->rootcontig[i] = PETSC_TRUE; 21 dat->rootdups[i] = PETSC_FALSE; 22 } 23 24 sf->leafbuflen[PETSCSF_REMOTE] = sf->nleaves; 25 dat->rootbuflen[PETSCSF_REMOTE] = sf->nroots; 26 sf->persistent = PETSC_FALSE; 27 sf->nleafreqs = 0; /* MPI collectives only need one request. We treat it as a root request. */ 28 dat->nrootreqs = 1; 29 PetscFunctionReturn(0); 30 } 31 32 static PetscErrorCode PetscSFBcastBegin_Allgather(PetscSF sf, MPI_Datatype unit, PetscMemType rootmtype, const void *rootdata, PetscMemType leafmtype, void *leafdata, MPI_Op op) { 33 PetscSFLink link; 34 PetscMPIInt sendcount; 35 MPI_Comm comm; 36 void *rootbuf = NULL, *leafbuf = NULL; /* buffer seen by MPI */ 37 MPI_Request *req; 38 39 PetscFunctionBegin; 40 PetscCall(PetscSFLinkCreate(sf, unit, rootmtype, rootdata, leafmtype, leafdata, op, PETSCSF_BCAST, &link)); 41 PetscCall(PetscSFLinkPackRootData(sf, link, PETSCSF_REMOTE, rootdata)); 42 PetscCall(PetscSFLinkCopyRootBufferInCaseNotUseGpuAwareMPI(sf, link, PETSC_TRUE /* device2host before sending */)); 43 PetscCall(PetscObjectGetComm((PetscObject)sf, &comm)); 44 PetscCall(PetscMPIIntCast(sf->nroots, &sendcount)); 45 PetscCall(PetscSFLinkGetMPIBuffersAndRequests(sf, link, PETSCSF_ROOT2LEAF, &rootbuf, &leafbuf, &req, NULL)); 46 PetscCall(PetscSFLinkSyncStreamBeforeCallMPI(sf, link, PETSCSF_ROOT2LEAF)); 47 PetscCallMPI(MPIU_Iallgather(rootbuf, sendcount, unit, leafbuf, sendcount, unit, comm, req)); 48 PetscFunctionReturn(0); 49 } 50 51 static PetscErrorCode PetscSFReduceBegin_Allgather(PetscSF sf, MPI_Datatype unit, PetscMemType leafmtype, const void *leafdata, PetscMemType rootmtype, void *rootdata, MPI_Op op) { 52 PetscSFLink link; 53 PetscInt rstart; 54 MPI_Comm comm; 55 PetscMPIInt rank, count, recvcount; 56 void *rootbuf = NULL, *leafbuf = NULL; /* buffer seen by MPI */ 57 PetscSF_Allgather *dat = (PetscSF_Allgather *)sf->data; 58 MPI_Request *req; 59 60 PetscFunctionBegin; 61 PetscCall(PetscSFLinkCreate(sf, unit, rootmtype, rootdata, leafmtype, leafdata, op, PETSCSF_REDUCE, &link)); 62 if (op == MPI_REPLACE) { 63 /* REPLACE is only meaningful when all processes have the same leafdata to reduce. Therefore copy from local leafdata is fine */ 64 PetscCall(PetscLayoutGetRange(sf->map, &rstart, NULL)); 65 PetscCall((*link->Memcpy)(link, rootmtype, rootdata, leafmtype, (const char *)leafdata + (size_t)rstart * link->unitbytes, (size_t)sf->nroots * link->unitbytes)); 66 if (PetscMemTypeDevice(leafmtype) && PetscMemTypeHost(rootmtype)) PetscCall((*link->SyncStream)(link)); /* Sync the device to host memcpy */ 67 } else { 68 PetscCall(PetscObjectGetComm((PetscObject)sf, &comm)); 69 PetscCallMPI(MPI_Comm_rank(comm, &rank)); 70 PetscCall(PetscSFLinkPackLeafData(sf, link, PETSCSF_REMOTE, leafdata)); 71 PetscCall(PetscSFLinkCopyLeafBufferInCaseNotUseGpuAwareMPI(sf, link, PETSC_TRUE /* device2host before sending */)); 72 PetscCall(PetscSFLinkGetMPIBuffersAndRequests(sf, link, PETSCSF_LEAF2ROOT, &rootbuf, &leafbuf, &req, NULL)); 73 PetscCall(PetscMPIIntCast(dat->rootbuflen[PETSCSF_REMOTE], &recvcount)); 74 if (rank == 0 && !link->leafbuf_alloc[PETSCSF_REMOTE][link->leafmtype_mpi]) { 75 PetscCall(PetscSFMalloc(sf, link->leafmtype_mpi, sf->leafbuflen[PETSCSF_REMOTE] * link->unitbytes, (void **)&link->leafbuf_alloc[PETSCSF_REMOTE][link->leafmtype_mpi])); 76 } 77 if (rank == 0 && link->leafbuf_alloc[PETSCSF_REMOTE][link->leafmtype_mpi] == leafbuf) leafbuf = MPI_IN_PLACE; 78 PetscCall(PetscMPIIntCast(sf->nleaves * link->bs, &count)); 79 PetscCall(PetscSFLinkSyncStreamBeforeCallMPI(sf, link, PETSCSF_LEAF2ROOT)); 80 PetscCallMPI(MPI_Reduce(leafbuf, link->leafbuf_alloc[PETSCSF_REMOTE][link->leafmtype_mpi], count, link->basicunit, op, 0, comm)); /* Must do reduce with MPI builltin datatype basicunit */ 81 PetscCallMPI(MPIU_Iscatter(link->leafbuf_alloc[PETSCSF_REMOTE][link->leafmtype_mpi], recvcount, unit, rootbuf, recvcount, unit, 0 /*rank 0*/, comm, req)); 82 } 83 PetscFunctionReturn(0); 84 } 85 86 static PetscErrorCode PetscSFBcastToZero_Allgather(PetscSF sf, MPI_Datatype unit, PetscMemType rootmtype, const void *rootdata, PetscMemType leafmtype, void *leafdata) { 87 PetscSFLink link; 88 PetscMPIInt rank; 89 90 PetscFunctionBegin; 91 PetscCall(PetscSFBcastBegin_Gather(sf, unit, rootmtype, rootdata, leafmtype, leafdata, MPI_REPLACE)); 92 PetscCall(PetscSFLinkGetInUse(sf, unit, rootdata, leafdata, PETSC_OWN_POINTER, &link)); 93 PetscCall(PetscSFLinkFinishCommunication(sf, link, PETSCSF_ROOT2LEAF)); 94 PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)sf), &rank)); 95 if (rank == 0 && PetscMemTypeDevice(leafmtype) && !sf->use_gpu_aware_mpi) { 96 PetscCall((*link->Memcpy)(link, PETSC_MEMTYPE_DEVICE, leafdata, PETSC_MEMTYPE_HOST, link->leafbuf[PETSCSF_REMOTE][PETSC_MEMTYPE_HOST], sf->leafbuflen[PETSCSF_REMOTE] * link->unitbytes)); 97 } 98 PetscCall(PetscSFLinkReclaim(sf, &link)); 99 PetscFunctionReturn(0); 100 } 101 102 PETSC_INTERN PetscErrorCode PetscSFCreate_Allgather(PetscSF sf) { 103 PetscSF_Allgather *dat = (PetscSF_Allgather *)sf->data; 104 105 PetscFunctionBegin; 106 sf->ops->BcastEnd = PetscSFBcastEnd_Basic; 107 sf->ops->ReduceEnd = PetscSFReduceEnd_Allgatherv; 108 109 /* Inherit from Allgatherv */ 110 sf->ops->Reset = PetscSFReset_Allgatherv; 111 sf->ops->Destroy = PetscSFDestroy_Allgatherv; 112 sf->ops->FetchAndOpBegin = PetscSFFetchAndOpBegin_Allgatherv; 113 sf->ops->FetchAndOpEnd = PetscSFFetchAndOpEnd_Allgatherv; 114 sf->ops->GetRootRanks = PetscSFGetRootRanks_Allgatherv; 115 sf->ops->CreateLocalSF = PetscSFCreateLocalSF_Allgatherv; 116 sf->ops->GetGraph = PetscSFGetGraph_Allgatherv; 117 sf->ops->GetLeafRanks = PetscSFGetLeafRanks_Allgatherv; 118 119 /* Allgather stuff */ 120 sf->ops->SetUp = PetscSFSetUp_Allgather; 121 sf->ops->BcastBegin = PetscSFBcastBegin_Allgather; 122 sf->ops->ReduceBegin = PetscSFReduceBegin_Allgather; 123 sf->ops->BcastToZero = PetscSFBcastToZero_Allgather; 124 125 PetscCall(PetscNewLog(sf, &dat)); 126 sf->data = (void *)dat; 127 PetscFunctionReturn(0); 128 } 129