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575 lines
17 KiB
C++
575 lines
17 KiB
C++
/*************************************************************************************
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Grid physics library, www.github.com/paboyle/Grid
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Source file: ./lib/communicator/Communicator_mpi.cc
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Copyright (C) 2015
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Author: Peter Boyle <paboyle@ph.ed.ac.uk>
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License along
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with this program; if not, write to the Free Software Foundation, Inc.,
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51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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See the full license in the file "LICENSE" in the top level distribution directory
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*************************************************************************************/
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/* END LEGAL */
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#include "Grid.h"
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#include <mpi.h>
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#include <numaif.h>
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namespace Grid {
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///////////////////////////////////////////////////////////////////////////////////////////////////
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// Info that is setup once and indept of cartesian layout
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///////////////////////////////////////////////////////////////////////////////////////////////////
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int CartesianCommunicator::ShmSetup = 0;
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MPI_Comm CartesianCommunicator::communicator_world;
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MPI_Comm CartesianCommunicator::ShmComm;
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MPI_Win CartesianCommunicator::ShmWindow;
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std::vector<int> CartesianCommunicator::GroupRanks;
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std::vector<int> CartesianCommunicator::MyGroup;
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std::vector<void *> CartesianCommunicator::ShmCommBufs;
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void *CartesianCommunicator::ShmBufferSelf(void)
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{
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return ShmCommBufs[ShmRank];
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}
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void *CartesianCommunicator::ShmBuffer(int rank)
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{
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int gpeer = GroupRanks[rank];
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if (gpeer == MPI_UNDEFINED){
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return NULL;
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} else {
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return ShmCommBufs[gpeer];
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}
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}
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void *CartesianCommunicator::ShmBufferTranslate(int rank,void * local_p)
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{
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int gpeer = GroupRanks[rank];
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if (gpeer == MPI_UNDEFINED){
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return NULL;
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} else {
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uint64_t offset = (uint64_t)local_p - (uint64_t)ShmCommBufs[ShmRank];
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uint64_t remote = (uint64_t)ShmCommBufs[gpeer]+offset;
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return (void *) remote;
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}
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}
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void CartesianCommunicator::Init(int *argc, char ***argv) {
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int flag;
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MPI_Initialized(&flag); // needed to coexist with other libs apparently
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if ( !flag ) {
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MPI_Init(argc,argv);
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}
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MPI_Comm_dup (MPI_COMM_WORLD,&communicator_world);
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MPI_Comm_rank(communicator_world,&WorldRank);
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MPI_Comm_size(communicator_world,&WorldSize);
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/////////////////////////////////////////////////////////////////////
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// Split into groups that can share memory
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/////////////////////////////////////////////////////////////////////
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MPI_Comm_split_type(communicator_world, MPI_COMM_TYPE_SHARED, 0, MPI_INFO_NULL,&ShmComm);
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MPI_Comm_rank(ShmComm ,&ShmRank);
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MPI_Comm_size(ShmComm ,&ShmSize);
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GroupSize = WorldSize/ShmSize;
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/////////////////////////////////////////////////////////////////////
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// find world ranks in our SHM group (i.e. which ranks are on our node)
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/////////////////////////////////////////////////////////////////////
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MPI_Group WorldGroup, ShmGroup;
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MPI_Comm_group (communicator_world, &WorldGroup);
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MPI_Comm_group (ShmComm, &ShmGroup);
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std::vector<int> world_ranks(WorldSize);
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GroupRanks.resize(WorldSize);
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MyGroup.resize(ShmSize);
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for(int r=0;r<WorldSize;r++) world_ranks[r]=r;
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MPI_Group_translate_ranks (WorldGroup,WorldSize,&world_ranks[0],ShmGroup, &GroupRanks[0]);
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///////////////////////////////////////////////////////////////////
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// Identify who is in my group and noninate the leader
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///////////////////////////////////////////////////////////////////
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int g=0;
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for(int rank=0;rank<WorldSize;rank++){
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if(GroupRanks[rank]!=MPI_UNDEFINED){
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assert(g<ShmSize);
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MyGroup[g++] = rank;
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}
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}
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std::sort(MyGroup.begin(),MyGroup.end(),std::less<int>());
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int myleader = MyGroup[0];
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std::vector<int> leaders_1hot(WorldSize,0);
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std::vector<int> leaders_group(GroupSize,0);
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leaders_1hot [ myleader ] = 1;
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///////////////////////////////////////////////////////////////////
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// global sum leaders over comm world
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///////////////////////////////////////////////////////////////////
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int ierr=MPI_Allreduce(MPI_IN_PLACE,&leaders_1hot[0],WorldSize,MPI_INT,MPI_SUM,communicator_world);
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assert(ierr==0);
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///////////////////////////////////////////////////////////////////
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// find the group leaders world rank
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///////////////////////////////////////////////////////////////////
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int group=0;
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for(int l=0;l<WorldSize;l++){
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if(leaders_1hot[l]){
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leaders_group[group++] = l;
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}
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}
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///////////////////////////////////////////////////////////////////
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// Identify the rank of the group in which I (and my leader) live
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///////////////////////////////////////////////////////////////////
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GroupRank=-1;
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for(int g=0;g<GroupSize;g++){
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if (myleader == leaders_group[g]){
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GroupRank=g;
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}
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}
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assert(GroupRank!=-1);
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//////////////////////////////////////////////////////////////////////////////////////////////////////////
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// allocate the shared window for our group
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//////////////////////////////////////////////////////////////////////////////////////////////////////////
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ShmCommBuf = 0;
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ierr = MPI_Win_allocate_shared(MAX_MPI_SHM_BYTES,1,MPI_INFO_NULL,ShmComm,&ShmCommBuf,&ShmWindow);
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assert(ierr==0);
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// KNL hack -- force to numa-domain 1 in flat
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#if 0
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for(uint64_t page=0;page<MAX_MPI_SHM_BYTES;page+=4096){
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void *pages = (void *) ( page + ShmCommBuf );
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int status;
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int flags=MPOL_MF_MOVE_ALL;
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int nodes=1; // numa domain == MCDRAM
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unsigned long count=1;
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ierr= move_pages(0,count, &pages,&nodes,&status,flags);
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if (ierr && (page==0)) perror("numa relocate command failed");
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}
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#endif
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MPI_Win_lock_all (MPI_MODE_NOCHECK, ShmWindow);
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/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
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// Plan: allocate a fixed SHM region. Scratch that is just used via some scheme during stencil comms, with no allocate free.
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/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
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ShmCommBufs.resize(ShmSize);
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for(int r=0;r<ShmSize;r++){
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MPI_Aint sz;
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int dsp_unit;
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MPI_Win_shared_query (ShmWindow, r, &sz, &dsp_unit, &ShmCommBufs[r]);
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}
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//////////////////////////////////////////////////////////////////////////////////////////////////////////
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// Verbose for now
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//////////////////////////////////////////////////////////////////////////////////////////////////////////
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if (WorldRank == 0){
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std::cout<<GridLogMessage<< "Grid MPI-3 configuration: detected ";
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std::cout<< WorldSize << " Ranks " ;
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std::cout<< GroupSize << " Nodes " ;
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std::cout<< ShmSize << " with ranks-per-node "<<std::endl;
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std::cout<<GridLogMessage <<"Grid MPI-3 configuration: allocated shared memory region of size ";
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std::cout<<std::hex << MAX_MPI_SHM_BYTES <<" ShmCommBuf address = "<<ShmCommBuf << std::dec<<std::endl;
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for(int g=0;g<GroupSize;g++){
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std::cout<<GridLogMessage<<" Node "<<g<<" led by MPI rank "<<leaders_group[g]<<std::endl;
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}
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std::cout<<GridLogMessage<<" Boss Node Shm Pointers are {";
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for(int g=0;g<ShmSize;g++){
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std::cout<<std::hex<<ShmCommBufs[g]<<std::dec;
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if(g!=ShmSize-1) std::cout<<",";
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else std::cout<<"}"<<std::endl;
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}
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}
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for(int g=0;g<GroupSize;g++){
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if ( (ShmRank == 0) && (GroupRank==g) ) std::cout<<GridLogMessage<<"["<<g<<"] Node Group "<<g<<" is ranks {";
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for(int r=0;r<ShmSize;r++){
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if ( (ShmRank == 0) && (GroupRank==g) ) {
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std::cout<<MyGroup[r];
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if(r<ShmSize-1) std::cout<<",";
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else std::cout<<"}"<<std::endl;
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}
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MPI_Barrier(communicator_world);
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}
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}
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assert(ShmSetup==0); ShmSetup=1;
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}
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////////////////////////////////////////////////////////////////////////////////////////////////////////////
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// Want to implement some magic ... Group sub-cubes into those on same node
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////////////////////////////////////////////////////////////////////////////////////////////////////////////
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void CartesianCommunicator::ShiftedRanks(int dim,int shift,int &source,int &dest)
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{
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std::vector<int> coor = _processor_coor;
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assert(std::abs(shift) <_processors[dim]);
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coor[dim] = (_processor_coor[dim] + shift + _processors[dim])%_processors[dim];
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Lexicographic::IndexFromCoor(coor,source,_processors);
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source = LexicographicToWorldRank[source];
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coor[dim] = (_processor_coor[dim] - shift + _processors[dim])%_processors[dim];
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Lexicographic::IndexFromCoor(coor,dest,_processors);
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dest = LexicographicToWorldRank[dest];
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}
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int CartesianCommunicator::RankFromProcessorCoor(std::vector<int> &coor)
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{
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int rank;
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Lexicographic::IndexFromCoor(coor,rank,_processors);
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rank = LexicographicToWorldRank[rank];
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return rank;
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}
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void CartesianCommunicator::ProcessorCoorFromRank(int rank, std::vector<int> &coor)
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{
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Lexicographic::CoorFromIndex(coor,rank,_processors);
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rank = LexicographicToWorldRank[rank];
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}
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CartesianCommunicator::CartesianCommunicator(const std::vector<int> &processors)
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{
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int ierr;
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communicator=communicator_world;
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_ndimension = processors.size();
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////////////////////////////////////////////////////////////////
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// Assert power of two shm_size.
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////////////////////////////////////////////////////////////////
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int log2size = -1;
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for(int i=0;i<=MAXLOG2RANKSPERNODE;i++){
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if ( (0x1<<i) == ShmSize ) {
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log2size = i;
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break;
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}
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}
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assert(log2size != -1);
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////////////////////////////////////////////////////////////////
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// Identify subblock of ranks on node spreading across dims
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// in a maximally symmetrical way
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////////////////////////////////////////////////////////////////
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int dim = 0;
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std::vector<int> WorldDims = processors;
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ShmDims.resize(_ndimension,1);
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GroupDims.resize(_ndimension);
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ShmCoor.resize(_ndimension);
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GroupCoor.resize(_ndimension);
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WorldCoor.resize(_ndimension);
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for(int l2=0;l2<log2size;l2++){
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while ( WorldDims[dim] / ShmDims[dim] <= 1 ) dim=(dim+1)%_ndimension;
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ShmDims[dim]*=2;
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dim=(dim+1)%_ndimension;
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}
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////////////////////////////////////////////////////////////////
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// Establish torus of processes and nodes with sub-blockings
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////////////////////////////////////////////////////////////////
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for(int d=0;d<_ndimension;d++){
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GroupDims[d] = WorldDims[d]/ShmDims[d];
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}
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////////////////////////////////////////////////////////////////
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// Check processor counts match
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////////////////////////////////////////////////////////////////
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_Nprocessors=1;
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_processors = processors;
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_processor_coor.resize(_ndimension);
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for(int i=0;i<_ndimension;i++){
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_Nprocessors*=_processors[i];
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}
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assert(WorldSize==_Nprocessors);
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////////////////////////////////////////////////////////////////
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// Establish mapping between lexico physics coord and WorldRank
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//
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////////////////////////////////////////////////////////////////
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LexicographicToWorldRank.resize(WorldSize,0);
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Lexicographic::CoorFromIndex(GroupCoor,GroupRank,GroupDims);
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Lexicographic::CoorFromIndex(ShmCoor,ShmRank,ShmDims);
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for(int d=0;d<_ndimension;d++){
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WorldCoor[d] = GroupCoor[d]*ShmDims[d]+ShmCoor[d];
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}
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_processor_coor = WorldCoor;
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int lexico;
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Lexicographic::IndexFromCoor(WorldCoor,lexico,WorldDims);
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LexicographicToWorldRank[lexico]=WorldRank;
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_processor = lexico;
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///////////////////////////////////////////////////////////////////
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// global sum Lexico to World mapping
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///////////////////////////////////////////////////////////////////
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ierr=MPI_Allreduce(MPI_IN_PLACE,&LexicographicToWorldRank[0],WorldSize,MPI_INT,MPI_SUM,communicator);
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assert(ierr==0);
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};
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void CartesianCommunicator::GlobalSum(uint32_t &u){
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int ierr=MPI_Allreduce(MPI_IN_PLACE,&u,1,MPI_UINT32_T,MPI_SUM,communicator);
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assert(ierr==0);
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}
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void CartesianCommunicator::GlobalSum(uint64_t &u){
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int ierr=MPI_Allreduce(MPI_IN_PLACE,&u,1,MPI_UINT64_T,MPI_SUM,communicator);
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assert(ierr==0);
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}
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void CartesianCommunicator::GlobalSum(float &f){
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int ierr=MPI_Allreduce(MPI_IN_PLACE,&f,1,MPI_FLOAT,MPI_SUM,communicator);
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assert(ierr==0);
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}
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void CartesianCommunicator::GlobalSumVector(float *f,int N)
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{
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int ierr=MPI_Allreduce(MPI_IN_PLACE,f,N,MPI_FLOAT,MPI_SUM,communicator);
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assert(ierr==0);
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}
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void CartesianCommunicator::GlobalSum(double &d)
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{
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int ierr = MPI_Allreduce(MPI_IN_PLACE,&d,1,MPI_DOUBLE,MPI_SUM,communicator);
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assert(ierr==0);
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}
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void CartesianCommunicator::GlobalSumVector(double *d,int N)
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{
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int ierr = MPI_Allreduce(MPI_IN_PLACE,d,N,MPI_DOUBLE,MPI_SUM,communicator);
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assert(ierr==0);
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}
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// Basic Halo comms primitive
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void CartesianCommunicator::SendToRecvFrom(void *xmit,
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int dest,
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void *recv,
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int from,
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int bytes)
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{
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std::vector<CommsRequest_t> reqs(0);
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SendToRecvFromBegin(reqs,xmit,dest,recv,from,bytes);
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SendToRecvFromComplete(reqs);
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}
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void CartesianCommunicator::SendRecvPacket(void *xmit,
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void *recv,
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int sender,
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int receiver,
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int bytes)
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{
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MPI_Status stat;
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assert(sender != receiver);
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int tag = sender;
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if ( _processor == sender ) {
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MPI_Send(xmit, bytes, MPI_CHAR,receiver,tag,communicator);
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}
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if ( _processor == receiver ) {
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MPI_Recv(recv, bytes, MPI_CHAR,sender,tag,communicator,&stat);
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}
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}
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// Basic Halo comms primitive
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void CartesianCommunicator::SendToRecvFromBegin(std::vector<CommsRequest_t> &list,
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void *xmit,
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int dest,
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void *recv,
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int from,
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int bytes)
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{
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#if 0
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this->StencilBarrier();
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MPI_Request xrq;
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MPI_Request rrq;
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static int sequence;
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int ierr;
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int tag;
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int check;
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assert(dest != _processor);
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assert(from != _processor);
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int gdest = GroupRanks[dest];
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int gfrom = GroupRanks[from];
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int gme = GroupRanks[_processor];
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sequence++;
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char *from_ptr = (char *)ShmCommBufs[ShmRank];
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int small = (bytes<MAX_MPI_SHM_BYTES);
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typedef uint64_t T;
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int words = bytes/sizeof(T);
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assert(((size_t)bytes &(sizeof(T)-1))==0);
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assert(gme == ShmRank);
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if ( small && (gdest !=MPI_UNDEFINED) ) {
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char *to_ptr = (char *)ShmCommBufs[gdest];
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assert(gme != gdest);
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T *ip = (T *)xmit;
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T *op = (T *)to_ptr;
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PARALLEL_FOR_LOOP
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for(int w=0;w<words;w++) {
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op[w]=ip[w];
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}
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bcopy(&_processor,&to_ptr[bytes],sizeof(_processor));
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bcopy(& sequence,&to_ptr[bytes+4],sizeof(sequence));
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} else {
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ierr =MPI_Isend(xmit, bytes, MPI_CHAR,dest,_processor,communicator,&xrq);
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assert(ierr==0);
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list.push_back(xrq);
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}
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this->StencilBarrier();
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if (small && (gfrom !=MPI_UNDEFINED) ) {
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T *ip = (T *)from_ptr;
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T *op = (T *)recv;
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PARALLEL_FOR_LOOP
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for(int w=0;w<words;w++) {
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op[w]=ip[w];
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}
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bcopy(&from_ptr[bytes] ,&tag ,sizeof(tag));
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bcopy(&from_ptr[bytes+4],&check,sizeof(check));
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assert(check==sequence);
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assert(tag==from);
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} else {
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ierr=MPI_Irecv(recv, bytes, MPI_CHAR,from,from,communicator,&rrq);
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assert(ierr==0);
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list.push_back(rrq);
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}
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this->StencilBarrier();
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#else
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MPI_Request xrq;
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MPI_Request rrq;
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int rank = _processor;
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int ierr;
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ierr =MPI_Isend(xmit, bytes, MPI_CHAR,dest,_processor,communicator,&xrq);
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ierr|=MPI_Irecv(recv, bytes, MPI_CHAR,from,from,communicator,&rrq);
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assert(ierr==0);
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list.push_back(xrq);
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list.push_back(rrq);
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#endif
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}
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void CartesianCommunicator::StencilSendToRecvFromBegin(std::vector<CommsRequest_t> &list,
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void *xmit,
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int dest,
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void *recv,
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int from,
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int bytes)
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{
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MPI_Request xrq;
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MPI_Request rrq;
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int ierr;
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assert(dest != _processor);
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assert(from != _processor);
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|
|
int gdest = GroupRanks[dest];
|
|
int gfrom = GroupRanks[from];
|
|
int gme = GroupRanks[_processor];
|
|
|
|
assert(gme == ShmRank);
|
|
|
|
if ( gdest == MPI_UNDEFINED ) {
|
|
ierr =MPI_Isend(xmit, bytes, MPI_CHAR,dest,_processor,communicator,&xrq);
|
|
assert(ierr==0);
|
|
list.push_back(xrq);
|
|
}
|
|
|
|
if ( gfrom ==MPI_UNDEFINED) {
|
|
ierr=MPI_Irecv(recv, bytes, MPI_CHAR,from,from,communicator,&rrq);
|
|
assert(ierr==0);
|
|
list.push_back(rrq);
|
|
}
|
|
|
|
}
|
|
|
|
|
|
void CartesianCommunicator::StencilSendToRecvFromComplete(std::vector<CommsRequest_t> &list)
|
|
{
|
|
SendToRecvFromComplete(list);
|
|
}
|
|
|
|
void CartesianCommunicator::StencilBarrier(void)
|
|
{
|
|
MPI_Win_sync (ShmWindow);
|
|
MPI_Barrier (ShmComm);
|
|
MPI_Win_sync (ShmWindow);
|
|
}
|
|
|
|
void CartesianCommunicator::SendToRecvFromComplete(std::vector<CommsRequest_t> &list)
|
|
{
|
|
int nreq=list.size();
|
|
std::vector<MPI_Status> status(nreq);
|
|
int ierr = MPI_Waitall(nreq,&list[0],&status[0]);
|
|
assert(ierr==0);
|
|
}
|
|
|
|
void CartesianCommunicator::Barrier(void)
|
|
{
|
|
int ierr = MPI_Barrier(communicator);
|
|
assert(ierr==0);
|
|
}
|
|
|
|
void CartesianCommunicator::Broadcast(int root,void* data, int bytes)
|
|
{
|
|
int ierr=MPI_Bcast(data,
|
|
bytes,
|
|
MPI_BYTE,
|
|
root,
|
|
communicator);
|
|
assert(ierr==0);
|
|
}
|
|
|
|
void CartesianCommunicator::BroadcastWorld(int root,void* data, int bytes)
|
|
{
|
|
int ierr= MPI_Bcast(data,
|
|
bytes,
|
|
MPI_BYTE,
|
|
root,
|
|
communicator_world);
|
|
assert(ierr==0);
|
|
}
|
|
|
|
}
|
|
|