Actual source code: sfgather.c
1: #include <../src/vec/is/sf/impls/basic/gatherv/sfgatherv.h>
2: #include <../src/vec/is/sf/impls/basic/allgather/sfallgather.h>
4: /* Reuse the type. The difference is some fields (i.e., displs, recvcounts) are not used in Gather, which is not a big deal */
5: typedef PetscSF_Allgatherv PetscSF_Gather;
7: PETSC_INTERN PetscErrorCode PetscSFBcastBegin_Gather(PetscSF sf, MPI_Datatype unit, PetscMemType rootmtype, const void *rootdata, PetscMemType leafmtype, void *leafdata, MPI_Op op)
8: {
9: PetscSFLink link;
10: PetscMPIInt sendcount;
11: MPI_Comm comm;
12: void *rootbuf = NULL, *leafbuf = NULL;
13: MPI_Request *req;
15: PetscSFLinkCreate(sf, unit, rootmtype, rootdata, leafmtype, leafdata, op, PETSCSF_BCAST, &link);
16: PetscSFLinkPackRootData(sf, link, PETSCSF_REMOTE, rootdata);
17: PetscSFLinkCopyRootBufferInCaseNotUseGpuAwareMPI(sf, link, PETSC_TRUE /* device2host before sending */);
18: PetscObjectGetComm((PetscObject)sf, &comm);
19: PetscMPIIntCast(sf->nroots, &sendcount);
20: PetscSFLinkGetMPIBuffersAndRequests(sf, link, PETSCSF_../../../../../..2LEAF, &rootbuf, &leafbuf, &req, NULL);
21: PetscSFLinkSyncStreamBeforeCallMPI(sf, link, PETSCSF_../../../../../..2LEAF);
22: MPIU_Igather(rootbuf == leafbuf ? MPI_IN_PLACE : rootbuf, sendcount, unit, leafbuf, sendcount, unit, 0 /*rank 0*/, comm, req);
23: return 0;
24: }
26: static PetscErrorCode PetscSFReduceBegin_Gather(PetscSF sf, MPI_Datatype unit, PetscMemType leafmtype, const void *leafdata, PetscMemType rootmtype, void *rootdata, MPI_Op op)
27: {
28: PetscSFLink link;
29: PetscMPIInt recvcount;
30: MPI_Comm comm;
31: void *rootbuf = NULL, *leafbuf = NULL;
32: MPI_Request *req;
34: PetscSFLinkCreate(sf, unit, rootmtype, rootdata, leafmtype, leafdata, op, PETSCSF_REDUCE, &link);
35: PetscSFLinkPackLeafData(sf, link, PETSCSF_REMOTE, leafdata);
36: PetscSFLinkCopyLeafBufferInCaseNotUseGpuAwareMPI(sf, link, PETSC_TRUE /* device2host before sending */);
37: PetscObjectGetComm((PetscObject)sf, &comm);
38: PetscMPIIntCast(sf->nroots, &recvcount);
39: PetscSFLinkGetMPIBuffersAndRequests(sf, link, PETSCSF_LEAF2../../../../../.., &rootbuf, &leafbuf, &req, NULL);
40: PetscSFLinkSyncStreamBeforeCallMPI(sf, link, PETSCSF_LEAF2../../../../../..);
41: MPIU_Iscatter(leafbuf, recvcount, unit, rootbuf == leafbuf ? MPI_IN_PLACE : rootbuf, recvcount, unit, 0 /*rank 0*/, comm, req);
42: return 0;
43: }
45: PETSC_INTERN PetscErrorCode PetscSFCreate_Gather(PetscSF sf)
46: {
47: PetscSF_Gather *dat = (PetscSF_Gather *)sf->data;
49: sf->ops->BcastEnd = PetscSFBcastEnd_Basic;
50: sf->ops->ReduceEnd = PetscSFReduceEnd_Basic;
52: /* Inherit from Allgatherv */
53: sf->ops->Reset = PetscSFReset_Allgatherv;
54: sf->ops->Destroy = PetscSFDestroy_Allgatherv;
55: sf->ops->GetGraph = PetscSFGetGraph_Allgatherv;
56: sf->ops->GetRootRanks = PetscSFGetRootRanks_Allgatherv;
57: sf->ops->GetLeafRanks = PetscSFGetLeafRanks_Allgatherv;
58: sf->ops->FetchAndOpEnd = PetscSFFetchAndOpEnd_Allgatherv;
59: sf->ops->CreateLocalSF = PetscSFCreateLocalSF_Allgatherv;
61: /* Inherit from Allgather */
62: sf->ops->SetUp = PetscSFSetUp_Allgather;
64: /* Inherit from Gatherv */
65: sf->ops->FetchAndOpBegin = PetscSFFetchAndOpBegin_Gatherv;
67: /* Gather stuff */
68: sf->ops->BcastBegin = PetscSFBcastBegin_Gather;
69: sf->ops->ReduceBegin = PetscSFReduceBegin_Gather;
71: PetscNew(&dat);
72: sf->data = (void *)dat;
73: return 0;
74: }