/*! This function calls subroutines that determine the spatial region covered * by the PM mesh. */ void long_range_init_regionsize(void) { #ifdef PERIODIC #ifdef PLACEHIGHRESREGION if(RestartFlag != 1) pm_init_regionsize(); pm_setup_nonperiodic_kernel(); #endif #else if(RestartFlag != 1) pm_init_regionsize(); pm_setup_nonperiodic_kernel(); #endif }
/*! This function computes the gravitational potential for ALL the particles. * First, the (short-range) tree potential is computed, and then, if needed, * the long range PM potential is added. */ void compute_potential(void) { int i; #ifndef NOGRAVITY int j, k, ret, sendTask, recvTask; int ndone, ndone_flag, dummy; int ngrp, place, nexport, nimport; double fac; MPI_Status status; double r2; if(All.ComovingIntegrationOn) set_softenings(); if(ThisTask == 0) { printf("Start computation of potential for all particles...\n"); fflush(stdout); } CPU_Step[CPU_MISC] += measure_time(); if(TreeReconstructFlag) { if(ThisTask == 0) printf("Tree construction.\n"); CPU_Step[CPU_MISC] += measure_time(); #if defined(SFR) || defined(BLACK_HOLES) rearrange_particle_sequence(); #endif force_treebuild(NumPart, NULL); CPU_Step[CPU_TREEBUILD] += measure_time(); TreeReconstructFlag = 0; if(ThisTask == 0) printf("Tree construction done.\n"); } /* allocate buffers to arrange communication */ All.BunchSize = (int) ((All.BufferSize * 1024 * 1024) / (sizeof(struct data_index) + sizeof(struct data_nodelist) + sizeof(struct gravdata_in) + sizeof(struct potdata_out) + sizemax(sizeof(struct gravdata_in), sizeof(struct potdata_out)))); DataIndexTable = (struct data_index *) mymalloc(All.BunchSize * sizeof(struct data_index)); DataNodeList = (struct data_nodelist *) mymalloc(All.BunchSize * sizeof(struct data_nodelist)); for(i = 0; i < NumPart; i++) if(P[i].Ti_current != All.Ti_Current) drift_particle(i, All.Ti_Current); i = 0; /* beginn with this index */ do { for(j = 0; j < NTask; j++) { Send_count[j] = 0; Exportflag[j] = -1; } /* do local particles and prepare export list */ for(nexport = 0; i < NumPart; i++) { #ifndef PMGRID ret = force_treeevaluate_potential(i, 0, &nexport, Send_count); #else ret = force_treeevaluate_potential_shortrange(i, 0, &nexport, Send_count); #endif if(ret < 0) break; /* export buffer has filled up */ } #ifdef MYSORT mysort_dataindex(DataIndexTable, nexport, sizeof(struct data_index), data_index_compare); #else qsort(DataIndexTable, nexport, sizeof(struct data_index), data_index_compare); #endif MPI_Allgather(Send_count, NTask, MPI_INT, Sendcount_matrix, NTask, MPI_INT, MPI_COMM_WORLD); for(j = 0, nimport = 0, Recv_offset[0] = 0, Send_offset[0] = 0; j < NTask; j++) { Recv_count[j] = Sendcount_matrix[j * NTask + ThisTask]; nimport += Recv_count[j]; if(j > 0) { Send_offset[j] = Send_offset[j - 1] + Send_count[j - 1]; Recv_offset[j] = Recv_offset[j - 1] + Recv_count[j - 1]; } } GravDataGet = (struct gravdata_in *) mymalloc(nimport * sizeof(struct gravdata_in)); GravDataIn = (struct gravdata_in *) mymalloc(nexport * sizeof(struct gravdata_in)); /* prepare particle data for export */ for(j = 0; j < nexport; j++) { place = DataIndexTable[j].Index; for(k = 0; k < 3; k++) GravDataIn[j].Pos[k] = P[place].Pos[k]; #ifdef UNEQUALSOFTENINGS GravDataIn[j].Type = P[place].Type; #ifdef ADAPTIVE_GRAVSOFT_FORGAS if(P[place].Type == 0) GravDataIn[j].Soft = SphP[place].Hsml; #endif #endif GravDataIn[j].OldAcc = P[place].OldAcc; for(k = 0; k < NODELISTLENGTH; k++) GravDataIn[j].NodeList[k] = DataNodeList[DataIndexTable[j].IndexGet].NodeList[k]; } /* exchange particle data */ for(ngrp = 1; ngrp < (1 << PTask); ngrp++) { sendTask = ThisTask; recvTask = ThisTask ^ ngrp; if(recvTask < NTask) { if(Send_count[recvTask] > 0 || Recv_count[recvTask] > 0) { /* get the particles */ MPI_Sendrecv(&GravDataIn[Send_offset[recvTask]], Send_count[recvTask] * sizeof(struct gravdata_in), MPI_BYTE, recvTask, TAG_POTENTIAL_A, &GravDataGet[Recv_offset[recvTask]], Recv_count[recvTask] * sizeof(struct gravdata_in), MPI_BYTE, recvTask, TAG_POTENTIAL_A, MPI_COMM_WORLD, &status); } } } myfree(GravDataIn); PotDataResult = (struct potdata_out *) mymalloc(nimport * sizeof(struct potdata_out)); PotDataOut = (struct potdata_out *) mymalloc(nexport * sizeof(struct potdata_out)); /* now do the particles that were sent to us */ for(j = 0; j < nimport; j++) { #ifndef PMGRID force_treeevaluate_potential(j, 1, &dummy, &dummy); #else force_treeevaluate_potential_shortrange(j, 1, &dummy, &dummy); #endif } if(i >= NumPart) ndone_flag = 1; else ndone_flag = 0; MPI_Allreduce(&ndone_flag, &ndone, 1, MPI_INT, MPI_SUM, MPI_COMM_WORLD); /* get the result */ for(ngrp = 1; ngrp < (1 << PTask); ngrp++) { sendTask = ThisTask; recvTask = ThisTask ^ ngrp; if(recvTask < NTask) { if(Send_count[recvTask] > 0 || Recv_count[recvTask] > 0) { /* send the results */ MPI_Sendrecv(&PotDataResult[Recv_offset[recvTask]], Recv_count[recvTask] * sizeof(struct potdata_out), MPI_BYTE, recvTask, TAG_POTENTIAL_B, &PotDataOut[Send_offset[recvTask]], Send_count[recvTask] * sizeof(struct potdata_out), MPI_BYTE, recvTask, TAG_POTENTIAL_B, MPI_COMM_WORLD, &status); } } } /* add the results to the local particles */ for(j = 0; j < nexport; j++) { place = DataIndexTable[j].Index; P[place].p.dPotential += PotDataOut[j].Potential; } myfree(PotDataOut); myfree(PotDataResult); myfree(GravDataGet); } while(ndone < NTask); myfree(DataNodeList); myfree(DataIndexTable); /* add correction to exclude self-potential */ for(i = 0; i < NumPart; i++) { #ifdef FLTROUNDOFFREDUCTION P[i].p.Potential = FLT(P[i].p.dPotential); #endif /* remove self-potential */ P[i].p.Potential += P[i].Mass / All.SofteningTable[P[i].Type]; if(All.ComovingIntegrationOn) if(All.PeriodicBoundariesOn) P[i].p.Potential -= 2.8372975 * pow(P[i].Mass, 2.0 / 3) * pow(All.Omega0 * 3 * All.Hubble * All.Hubble / (8 * M_PI * All.G), 1.0 / 3); } /* multiply with the gravitational constant */ for(i = 0; i < NumPart; i++) P[i].p.Potential *= All.G; #ifdef PMGRID #ifdef PERIODIC pmpotential_periodic(); #ifdef PLACEHIGHRESREGION i = pmpotential_nonperiodic(1); if(i == 1) /* this is returned if a particle lied outside allowed range */ { pm_init_regionsize(); pm_setup_nonperiodic_kernel(); i = pmpotential_nonperiodic(1); /* try again */ } if(i == 1) endrun(88686); #endif #else i = pmpotential_nonperiodic(0); if(i == 1) /* this is returned if a particle lied outside allowed range */ { pm_init_regionsize(); pm_setup_nonperiodic_kernel(); i = pmpotential_nonperiodic(0); /* try again */ } if(i == 1) endrun(88687); #ifdef PLACEHIGHRESREGION i = pmpotential_nonperiodic(1); if(i == 1) /* this is returned if a particle lied outside allowed range */ { pm_init_regionsize(); i = pmpotential_nonperiodic(1); } if(i != 0) endrun(88688); #endif #endif #endif if(All.ComovingIntegrationOn) { #ifndef PERIODIC fac = -0.5 * All.Omega0 * All.Hubble * All.Hubble; for(i = 0; i < NumPart; i++) { for(k = 0, r2 = 0; k < 3; k++) r2 += P[i].Pos[k] * P[i].Pos[k]; P[i].p.Potential += fac * r2; } #endif } else { fac = -0.5 * All.OmegaLambda * All.Hubble * All.Hubble; if(fac != 0) { for(i = 0; i < NumPart; i++) { for(k = 0, r2 = 0; k < 3; k++) r2 += P[i].Pos[k] * P[i].Pos[k]; P[i].p.Potential += fac * r2; } } } if(ThisTask == 0) { printf("potential done.\n"); fflush(stdout); } #else for(i = 0; i < NumPart; i++) P[i].Potential = 0; #endif CPU_Step[CPU_POTENTIAL] += measure_time(); }
/*! This function computes the gravitational potential for ALL the particles. * First, the (short-range) tree potential is computed, and then, if needed, * the long range PM potential is added. */ void compute_potential(void) { int i; #ifndef NOGRAVITY long long ntot, ntotleft; int j, k, level, sendTask, recvTask; int ndone; int maxfill, ngrp, place, nexport; int *nsend, *noffset, *nsend_local, *nbuffer, *ndonelist, *numlist; double fac; double t0, t1, tstart, tend; #ifndef NOMPI MPI_Status status; #endif double r2; t0 = second(); if(All.ComovingIntegrationOn) set_softenings(); if(ThisTask == 0) { printf("Start computation of potential for all particles...\n"); fflush(stdout); } tstart = second(); if(TreeReconstructFlag) { if(ThisTask == 0) printf("Tree construction.\n"); force_treebuild(NumPart); TreeReconstructFlag = 0; if(ThisTask == 0) printf("Tree construction done.\n"); } tend = second(); All.CPU_TreeConstruction += timediff(tstart, tend); numlist = malloc(NTask * sizeof(int) * NTask); #ifndef NOMPI MPI_Allgather(&NumPart, 1, MPI_INT, numlist, 1, MPI_INT, GADGET_WORLD); #else numlist[0] = NumPart; #endif for(i = 0, ntot = 0; i < NTask; i++) ntot += numlist[i]; free(numlist); noffset = malloc(sizeof(int) * NTask); /* offsets of bunches in common list */ nbuffer = malloc(sizeof(int) * NTask); nsend_local = malloc(sizeof(int) * NTask); nsend = malloc(sizeof(int) * NTask * NTask); ndonelist = malloc(sizeof(int) * NTask); i = 0; /* beginn with this index */ ntotleft = ntot; /* particles left for all tasks together */ while(ntotleft > 0) { for(j = 0; j < NTask; j++) nsend_local[j] = 0; /* do local particles and prepare export list */ for(nexport = 0, ndone = 0; i < NumPart && nexport < All.BunchSizeForce - NTask; i++) { ndone++; for(j = 0; j < NTask; j++) Exportflag[j] = 0; #ifndef PMGRID force_treeevaluate_potential(i, 0); #else force_treeevaluate_potential_shortrange(i, 0); #endif for(j = 0; j < NTask; j++) { if(Exportflag[j]) { for(k = 0; k < 3; k++) GravDataGet[nexport].u.Pos[k] = P[i].Pos[k]; #ifdef UNEQUALSOFTENINGS GravDataGet[nexport].Type = P[i].Type; #ifdef ADAPTIVE_GRAVSOFT_FORGAS if(P[i].Type == 0) GravDataGet[nexport].Soft = SphP[i].Hsml; #endif #endif GravDataGet[nexport].w.OldAcc = P[i].OldAcc; GravDataIndexTable[nexport].Task = j; GravDataIndexTable[nexport].Index = i; GravDataIndexTable[nexport].SortIndex = nexport; nexport++; nsend_local[j]++; } } } qsort(GravDataIndexTable, nexport, sizeof(struct gravdata_index), grav_tree_compare_key); for(j = 0; j < nexport; j++) GravDataIn[j] = GravDataGet[GravDataIndexTable[j].SortIndex]; for(j = 1, noffset[0] = 0; j < NTask; j++) noffset[j] = noffset[j - 1] + nsend_local[j - 1]; #ifndef NOMPI MPI_Allgather(nsend_local, NTask, MPI_INT, nsend, NTask, MPI_INT, GADGET_WORLD); #else nsend[0] = nsend_local[0]; #endif /* now do the particles that need to be exported */ for(level = 1; level < (1 << PTask); level++) { for(j = 0; j < NTask; j++) nbuffer[j] = 0; for(ngrp = level; ngrp < (1 << PTask); ngrp++) { maxfill = 0; for(j = 0; j < NTask; j++) { if((j ^ ngrp) < NTask) if(maxfill < nbuffer[j] + nsend[(j ^ ngrp) * NTask + j]) maxfill = nbuffer[j] + nsend[(j ^ ngrp) * NTask + j]; } if(maxfill >= All.BunchSizeForce) break; sendTask = ThisTask; recvTask = ThisTask ^ ngrp; #ifndef NOMPI if(recvTask < NTask) { if(nsend[ThisTask * NTask + recvTask] > 0 || nsend[recvTask * NTask + ThisTask] > 0) { /* get the particles */ MPI_Sendrecv(&GravDataIn[noffset[recvTask]], nsend_local[recvTask] * sizeof(struct gravdata_in), MPI_BYTE, recvTask, TAG_POTENTIAL_A, &GravDataGet[nbuffer[ThisTask]], nsend[recvTask * NTask + ThisTask] * sizeof(struct gravdata_in), MPI_BYTE, recvTask, TAG_POTENTIAL_A, GADGET_WORLD, &status); } } #endif for(j = 0; j < NTask; j++) if((j ^ ngrp) < NTask) nbuffer[j] += nsend[(j ^ ngrp) * NTask + j]; } for(j = 0; j < nbuffer[ThisTask]; j++) { #ifndef PMGRID force_treeevaluate_potential(j, 1); #else force_treeevaluate_potential_shortrange(j, 1); #endif } /* get the result */ for(j = 0; j < NTask; j++) nbuffer[j] = 0; for(ngrp = level; ngrp < (1 << PTask); ngrp++) { maxfill = 0; for(j = 0; j < NTask; j++) { if((j ^ ngrp) < NTask) if(maxfill < nbuffer[j] + nsend[(j ^ ngrp) * NTask + j]) maxfill = nbuffer[j] + nsend[(j ^ ngrp) * NTask + j]; } if(maxfill >= All.BunchSizeForce) break; sendTask = ThisTask; recvTask = ThisTask ^ ngrp; #ifndef NOMPI if(recvTask < NTask) { if(nsend[ThisTask * NTask + recvTask] > 0 || nsend[recvTask * NTask + ThisTask] > 0) { /* send the results */ MPI_Sendrecv(&GravDataResult[nbuffer[ThisTask]], nsend[recvTask * NTask + ThisTask] * sizeof(struct gravdata_in), MPI_BYTE, recvTask, TAG_POTENTIAL_B, &GravDataOut[noffset[recvTask]], nsend_local[recvTask] * sizeof(struct gravdata_in), MPI_BYTE, recvTask, TAG_POTENTIAL_B, GADGET_WORLD, &status); /* add the result to the particles */ for(j = 0; j < nsend_local[recvTask]; j++) { place = GravDataIndexTable[noffset[recvTask] + j].Index; P[place].Potential += GravDataOut[j + noffset[recvTask]].u.Potential; } } } #endif for(j = 0; j < NTask; j++) if((j ^ ngrp) < NTask) nbuffer[j] += nsend[(j ^ ngrp) * NTask + j]; } level = ngrp - 1; } #ifndef NOMPI MPI_Allgather(&ndone, 1, MPI_INT, ndonelist, 1, MPI_INT, GADGET_WORLD); #else ndonelist[0] = ndone; #endif // NOMPI for(j = 0; j < NTask; j++) ntotleft -= ndonelist[j]; } free(ndonelist); free(nsend); free(nsend_local); free(nbuffer); free(noffset); /* add correction to exclude self-potential */ for(i = 0; i < NumPart; i++) { /* remove self-potential */ P[i].Potential += P[i].Mass / All.SofteningTable[P[i].Type]; if(All.ComovingIntegrationOn) if(All.PeriodicBoundariesOn) P[i].Potential -= 2.8372975 * pow(P[i].Mass, 2.0 / 3) * pow(All.Omega0 * 3 * All.Hubble * All.Hubble / (8 * M_PI * All.G), 1.0 / 3); } /* multiply with the gravitational constant */ for(i = 0; i < NumPart; i++) P[i].Potential *= All.G; #ifdef PMGRID #ifdef PERIODIC pmpotential_periodic(); #ifdef PLACEHIGHRESREGION i = pmpotential_nonperiodic(1); if(i == 1) /* this is returned if a particle lied outside allowed range */ { pm_init_regionsize(); pm_setup_nonperiodic_kernel(); i = pmpotential_nonperiodic(1); /* try again */ } if(i == 1) endrun(88686); #endif #else i = pmpotential_nonperiodic(0); if(i == 1) /* this is returned if a particle lied outside allowed range */ { pm_init_regionsize(); pm_setup_nonperiodic_kernel(); i = pmpotential_nonperiodic(0); /* try again */ } if(i == 1) endrun(88687); #ifdef PLACEHIGHRESREGION i = pmpotential_nonperiodic(1); if(i == 1) /* this is returned if a particle lied outside allowed range */ { pm_init_regionsize(); i = pmpotential_nonperiodic(1); } if(i != 0) endrun(88688); #endif #endif #endif if(All.ComovingIntegrationOn) { #ifndef PERIODIC fac = -0.5 * All.Omega0 * All.Hubble * All.Hubble; for(i = 0; i < NumPart; i++) { for(k = 0, r2 = 0; k < 3; k++) r2 += P[i].Pos[k] * P[i].Pos[k]; P[i].Potential += fac * r2; } #endif } else { fac = -0.5 * All.OmegaLambda * All.Hubble * All.Hubble; if(fac != 0) { for(i = 0; i < NumPart; i++) { for(k = 0, r2 = 0; k < 3; k++) r2 += P[i].Pos[k] * P[i].Pos[k]; P[i].Potential += fac * r2; } } } if(ThisTask == 0) { printf("potential done.\n"); fflush(stdout); } t1 = second(); All.CPU_Potential += timediff(t0, t1); #else for(i = 0; i < NumPart; i++) P[i].Potential = 0; #endif }
/*! This function is a driver routine for the long-range PM force * computation. It calls periodic and/or non-periodic FFT routines as needed * for the present simulation set-up. */ void long_range_force(void) { int i; #ifndef PERIODIC int j; double fac; #endif for(i = 0; i < NumPart; i++) P[i].GravPM[0] = P[i].GravPM[1] = P[i].GravPM[2] = 0; #ifdef NOGRAVITY return; #endif #ifdef PERIODIC pmforce_periodic(); #ifdef PLACEHIGHRESREGION i = pmforce_nonperiodic(1); if(i == 1) /* this is returned if a particle lied outside allowed range */ { pm_init_regionsize(); pm_setup_nonperiodic_kernel(); i = pmforce_nonperiodic(1); /* try again */ } if(i == 1) endrun(68686); #endif #else i = pmforce_nonperiodic(0); if(i == 1) /* this is returned if a particle lied outside allowed range */ { pm_init_regionsize(); pm_setup_nonperiodic_kernel(); i = pmforce_nonperiodic(0); /* try again */ } if(i == 1) endrun(68687); #ifdef PLACEHIGHRESREGION i = pmforce_nonperiodic(1); if(i == 1) /* this is returned if a particle lied outside allowed range */ { pm_init_regionsize(); pm_setup_nonperiodic_kernel(); /* try again */ for(i = 0; i < NumPart; i++) P[i].GravPM[0] = P[i].GravPM[1] = P[i].GravPM[2] = 0; i = pmforce_nonperiodic(0) + pmforce_nonperiodic(1); } if(i != 0) endrun(68688); #endif #endif #ifndef PERIODIC if(All.ComovingIntegrationOn) { fac = 0.5 * All.Hubble * All.Hubble * All.Omega0; for(i = 0; i < NumPart; i++) for(j = 0; j < 3; j++) P[i].GravPM[j] += fac * P[i].Pos[j]; } /* Finally, the following factor allows a computation of cosmological simulation with vacuum energy in physical coordinates */ if(All.ComovingIntegrationOn == 0) { fac = All.OmegaLambda * All.Hubble * All.Hubble; for(i = 0; i < NumPart; i++) for(j = 0; j < 3; j++) P[i].GravPM[j] += fac * P[i].Pos[j]; } #endif }