Actual source code: sfgatherv.c
petsc-3.15.0 2021-03-30
2: #include <../src/vec/is/sf/impls/basic/gatherv/sfgatherv.h>
4: /* Reuse the type. The difference is some fields (displs, recvcounts) are only significant
5: on rank 0 in Gatherv. On other ranks they are harmless NULL.
6: */
7: typedef PetscSF_Allgatherv PetscSF_Gatherv;
9: PETSC_INTERN PetscErrorCode PetscSFBcastBegin_Gatherv(PetscSF sf,MPI_Datatype unit,PetscMemType rootmtype,const void *rootdata,PetscMemType leafmtype,void *leafdata,MPI_Op op)
10: {
11: PetscErrorCode ierr;
12: PetscSFLink link;
13: PetscMPIInt sendcount;
14: MPI_Comm comm;
15: PetscSF_Gatherv *dat = (PetscSF_Gatherv*)sf->data;
16: void *rootbuf = NULL,*leafbuf = NULL; /* buffer seen by MPI */
17: MPI_Request *req;
20: PetscSFLinkCreate(sf,unit,rootmtype,rootdata,leafmtype,leafdata,op,PETSCSF_BCAST,&link);
21: PetscSFLinkPackRootData(sf,link,PETSCSF_REMOTE,rootdata);
22: PetscSFLinkCopyRootBufferInCaseNotUseGpuAwareMPI(sf,link,PETSC_TRUE/* device2host before sending */);
23: PetscObjectGetComm((PetscObject)sf,&comm);
24: PetscMPIIntCast(sf->nroots,&sendcount);
25: PetscSFLinkGetMPIBuffersAndRequests(sf,link,PETSCSF_../../../../../..2LEAF,&rootbuf,&leafbuf,&req,NULL);
26: PetscSFLinkSyncStreamBeforeCallMPI(sf,link,PETSCSF_../../../../../..2LEAF);
27: MPIU_Igatherv(rootbuf,sendcount,unit,leafbuf,dat->recvcounts,dat->displs,unit,0/*rank 0*/,comm,req);
28: return(0);
29: }
31: static PetscErrorCode PetscSFReduceBegin_Gatherv(PetscSF sf,MPI_Datatype unit,PetscMemType leafmtype,const void *leafdata,PetscMemType rootmtype,void *rootdata,MPI_Op op)
32: {
33: PetscErrorCode ierr;
34: PetscSFLink link;
35: PetscMPIInt recvcount;
36: MPI_Comm comm;
37: PetscSF_Gatherv *dat = (PetscSF_Gatherv*)sf->data;
38: void *rootbuf = NULL,*leafbuf = NULL; /* buffer seen by MPI */
39: MPI_Request *req;
42: PetscSFLinkCreate(sf,unit,rootmtype,rootdata,leafmtype,leafdata,op,PETSCSF_REDUCE,&link);
43: PetscSFLinkPackLeafData(sf,link,PETSCSF_REMOTE,leafdata);
44: PetscSFLinkCopyLeafBufferInCaseNotUseGpuAwareMPI(sf,link,PETSC_TRUE/* device2host before sending */);
45: PetscObjectGetComm((PetscObject)sf,&comm);
46: PetscMPIIntCast(sf->nroots,&recvcount);
47: PetscSFLinkGetMPIBuffersAndRequests(sf,link,PETSCSF_LEAF2../../../../../..,&rootbuf,&leafbuf,&req,NULL);
48: PetscSFLinkSyncStreamBeforeCallMPI(sf,link,PETSCSF_LEAF2../../../../../..);
49: MPIU_Iscatterv(leafbuf,dat->recvcounts,dat->displs,unit,rootbuf,recvcount,unit,0,comm,req);
50: return(0);
51: }
53: PETSC_INTERN PetscErrorCode PetscSFFetchAndOpBegin_Gatherv(PetscSF sf,MPI_Datatype unit,PetscMemType rootmtype,void *rootdata,PetscMemType leafmtype,const void *leafdata,void *leafupdate,MPI_Op op)
54: {
55: PetscErrorCode ierr;
58: /* In Gatherv, each root only has one leaf. So we just need to bcast rootdata to leafupdate and then reduce leafdata to rootdata */
59: PetscSFBcastBegin(sf,unit,rootdata,leafupdate,MPI_REPLACE);
60: PetscSFBcastEnd(sf,unit,rootdata,leafupdate,MPI_REPLACE);
61: PetscSFReduceBegin(sf,unit,leafdata,rootdata,op);
62: return(0);
63: }
65: PETSC_INTERN PetscErrorCode PetscSFCreate_Gatherv(PetscSF sf)
66: {
67: PetscErrorCode ierr;
68: PetscSF_Gatherv *dat = (PetscSF_Gatherv*)sf->data;
71: sf->ops->BcastEnd = PetscSFBcastEnd_Basic;
72: sf->ops->ReduceEnd = PetscSFReduceEnd_Basic;
74: /* Inherit from Allgatherv */
75: sf->ops->SetUp = PetscSFSetUp_Allgatherv;
76: sf->ops->Reset = PetscSFReset_Allgatherv;
77: sf->ops->Destroy = PetscSFDestroy_Allgatherv;
78: sf->ops->GetGraph = PetscSFGetGraph_Allgatherv;
79: sf->ops->GetLeafRanks = PetscSFGetLeafRanks_Allgatherv;
80: sf->ops->GetRootRanks = PetscSFGetRootRanks_Allgatherv;
81: sf->ops->FetchAndOpEnd = PetscSFFetchAndOpEnd_Allgatherv;
82: sf->ops->CreateLocalSF = PetscSFCreateLocalSF_Allgatherv;
84: /* Gatherv stuff */
85: sf->ops->BcastBegin = PetscSFBcastBegin_Gatherv;
86: sf->ops->ReduceBegin = PetscSFReduceBegin_Gatherv;
87: sf->ops->FetchAndOpBegin = PetscSFFetchAndOpBegin_Gatherv;
89: PetscNewLog(sf,&dat);
90: sf->data = (void*)dat;
91: return(0);
92: }