src/gromacs/mdlib/simulationsignal.cpp

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
   3  *
   4  * Copyright (c) 1991-2000, University of Groningen, The Netherlands.
   5  * Copyright (c) 2001-2004, The GROMACS development team.
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   8  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
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  38 /*! \internal \file
  39  *
  40  * \brief This file defines functions for inter- and intra-simulation
  41  * signalling by mdrun.
  42  *
  43  * This handles details of responding to termination conditions,
  44  * coordinating checkpoints, and coordinating multi-simulations.
  45  *
  46  * \todo Move this to mdrunutility module alongside gathering
  47  * multi-simulation communication infrastructure there.
  48  *
  49  * \author Berk Hess <hess@kth.se>
  50  * \author Mark Abraham <mark.j.abraham@gmail.com>
  51  * \ingroup module_mdlib
  52  */
  53
  54 #include "gmxpre.h"
  55
  56 #include "simulationsignal.h"
  57
  58 #include <algorithm>
  59
  60 #include "gromacs/gmxlib/network.h"
  61 #include "gromacs/mdrunutility/multisim.h"
  62 #include "gromacs/mdtypes/commrec.h"
  63 #include "gromacs/utility/arrayref.h"
  64 #include "gromacs/utility/gmxassert.h"
  65 #include "gromacs/utility/real.h"
  66
  67 namespace gmx
  68 {
  69
  70 SimulationSignaller::SimulationSignaller(SimulationSignals*    signals,
  71                                          const t_commrec*      cr,
  72                                          const gmx_multisim_t* ms,
  73                                          bool                  doInterSim,
  74                                          bool                  doIntraSim) :
  75     signals_(signals),
  76     cr_(cr),
  77     ms_(ms),
  78     doInterSim_(doInterSim),
  79     doIntraSim_(doInterSim || doIntraSim),
  80     mpiBuffer_{}
  81 {
  82 }
  83
  84 gmx::ArrayRef<real> SimulationSignaller::getCommunicationBuffer()
  85 {
  86     if (doIntraSim_)
  87     {
  88         std::transform(std::begin(*signals_), std::end(*signals_), std::begin(mpiBuffer_),
  89                        [](const SimulationSignals::value_type& s) { return s.sig; });
  90
  91         return mpiBuffer_;
  92     }
  93     else
  94     {
  95         return {};
  96     }
  97 }
  98
  99 void SimulationSignaller::signalInterSim()
 100 {
 101     if (!doInterSim_)
 102     {
 103         return;
 104     }
 105     // The situations that lead to doInterSim_ == true without a
 106     // multi-simulation begin active should already have issued an
 107     // error at mdrun time in release mode, so there's no need for a
 108     // release-mode assertion.
 109     GMX_ASSERT(isMultiSim(ms_), "Cannot do inter-simulation signalling without a multi-simulation");
 110     if (MASTER(cr_))
 111     {
 112         // Communicate the signals between the simulations.
 113         gmx_sum_sim(eglsNR, mpiBuffer_.data(), ms_);
 114     }
 115     if (DOMAINDECOMP(cr_))
 116     {
 117         // Communicate the signals from the master to the others.
 118         gmx_bcast(eglsNR * sizeof(mpiBuffer_[0]), mpiBuffer_.data(), cr_->mpi_comm_mygroup);
 119     }
 120 }
 121
 122 void SimulationSignaller::setSignals()
 123 {
 124     if (!doIntraSim_)
 125     {
 126         return;
 127     }
 128
 129     SimulationSignals& s = *signals_;
 130     for (size_t i = 0; i < s.size(); i++)
 131     {
 132         if (doInterSim_ || s[i].isLocal)
 133         {
 134             // Floating-point reduction of integer values is always
 135             // exact, so we can use a simple cast.
 136             signed char gsi = static_cast<signed char>(mpiBuffer_[i]);
 137
 138             /* Set the communicated signal only when it is non-zero,
 139              * since a previously set signal might not have been
 140              * handled immediately. */
 141             if (gsi != 0)
 142             {
 143                 s[i].set = gsi;
 144             }
 145             // Turn off any local signal now that it has been processed.
 146             s[i].sig = 0;
 147         }
 148     }
 149 }
 150
 151 void SimulationSignaller::finalizeSignals()
 152 {
 153     signalInterSim();
 154     setSignals();
 155 }
 156
 157 } // namespace gmx