StreamSchedule.cc

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#include "FWCore/Framework/src/StreamSchedule.h"

#include "DataFormats/Provenance/interface/BranchIDListHelper.h"
#include "DataFormats/Provenance/interface/ProcessConfiguration.h"
#include "DataFormats/Provenance/interface/ProductRegistry.h"
#include "FWCore/Framework/interface/OutputModuleDescription.h"
#include "FWCore/Framework/interface/TriggerNamesService.h"
#include "FWCore/Framework/interface/TriggerReport.h"
#include "FWCore/Framework/interface/TriggerTimingReport.h"
#include "FWCore/Framework/src/Factory.h"
#include "FWCore/Framework/src/OutputModuleCommunicator.h"
#include "FWCore/Framework/src/TriggerResultInserter.h"
#include "FWCore/Framework/src/PathStatusInserter.h"
#include "FWCore/Framework/src/EndPathStatusInserter.h"
#include "FWCore/Framework/src/WorkerInPath.h"
#include "FWCore/Framework/src/ModuleHolder.h"
#include "FWCore/Framework/src/WorkerT.h"
#include "FWCore/Framework/src/ModuleRegistry.h"
#include "FWCore/MessageLogger/interface/MessageLogger.h"
#include "FWCore/ParameterSet/interface/ParameterSet.h"
#include "FWCore/ParameterSet/interface/ParameterSetDescription.h"
#include "FWCore/ParameterSet/interface/Registry.h"
#include "FWCore/ServiceRegistry/interface/PathContext.h"
#include "FWCore/Utilities/interface/Algorithms.h"
#include "FWCore/Utilities/interface/ConvertException.h"
#include "FWCore/Utilities/interface/ExceptionCollector.h"
#include "FWCore/Concurrency/interface/WaitingTaskHolder.h"

#include "LuminosityBlockProcessingStatus.h"

#include <algorithm>
#include <cassert>
#include <cstdlib>
#include <functional>
#include <iomanip>
#include <list>
#include <map>
#include <exception>

namespace edm {
  namespace {

    // Function template to transform each element in the input range to
    // a value placed into the output range. The supplied function
    // should take a const_reference to the 'input', and write to a
    // reference to the 'output'.
    template <typename InputIterator, typename ForwardIterator, typename Func>
    void
    transform_into(InputIterator begin, InputIterator end,
                   ForwardIterator out, Func func) {
      for (; begin != end; ++begin, ++out) func(*begin, *out);
    }

    // Function template that takes a sequence 'from', a sequence
    // 'to', and a callable object 'func'. It and applies
    // transform_into to fill the 'to' sequence with the values
    // calcuated by the callable object, taking care to fill the
    // outupt only if all calls succeed.
    template <typename FROM, typename TO, typename FUNC>
    void
    fill_summary(FROM const& from, TO& to, FUNC func) {
      if(to.size()!=from.size()) {
        TO temp(from.size());
        transform_into(from.begin(), from.end(), temp.begin(), func);
        to.swap(temp);
      } else {
        transform_into(from.begin(), from.end(), to.begin(), func);
      }
    }

    // -----------------------------

    // Here we make the trigger results inserter directly.  This should
    // probably be a utility in the WorkerRegistry or elsewhere.

    StreamSchedule::WorkerPtr
    makeInserter(ExceptionToActionTable const& actions,
                 std::shared_ptr<ActivityRegistry> areg,
                 std::shared_ptr<TriggerResultInserter> inserter) {
      StreamSchedule::WorkerPtr ptr(new edm::WorkerT<TriggerResultInserter::ModuleType>(inserter, inserter->moduleDescription(), &actions));
      ptr->setActivityRegistry(areg);
      return ptr;
    }

    void
    initializeBranchToReadingWorker(ParameterSet const& opts,
                                    ProductRegistry const& preg,
                                    std::multimap<std::string,Worker*>& branchToReadingWorker)
    {
      // See if any data has been marked to be deleted early (removing any duplicates)
      auto vBranchesToDeleteEarly = opts.getUntrackedParameter<std::vector<std::string>>("canDeleteEarly");
      if(not vBranchesToDeleteEarly.empty()) {
        std::sort(vBranchesToDeleteEarly.begin(),vBranchesToDeleteEarly.end(),std::less<std::string>());
        vBranchesToDeleteEarly.erase(std::unique(vBranchesToDeleteEarly.begin(),vBranchesToDeleteEarly.end()),
                                     vBranchesToDeleteEarly.end());
        
        // Are the requested items in the product registry?
        auto allBranchNames = preg.allBranchNames();
        //the branch names all end with a period, which we do not want to compare with
        for(auto & b:allBranchNames) {
          b.resize(b.size()-1);
        }
        std::sort(allBranchNames.begin(),allBranchNames.end(),std::less<std::string>());
        std::vector<std::string> temp;
        temp.reserve(vBranchesToDeleteEarly.size());  
        
        std::set_intersection(vBranchesToDeleteEarly.begin(),vBranchesToDeleteEarly.end(),
                              allBranchNames.begin(),allBranchNames.end(),
                              std::back_inserter(temp));
        vBranchesToDeleteEarly.swap(temp);
        if(temp.size() != vBranchesToDeleteEarly.size()) {
          std::vector<std::string> missingProducts;
          std::set_difference(temp.begin(),temp.end(),
                              vBranchesToDeleteEarly.begin(),vBranchesToDeleteEarly.end(),
                              std::back_inserter(missingProducts));
          LogInfo l("MissingProductsForCanDeleteEarly");
          l<<"The following products in the 'canDeleteEarly' list are not available in this job and will be ignored.";
          for(auto const& n:missingProducts){
            l<<"\n "<<n;
          }
        }
        //set placeholder for the branch, we will remove the nullptr if a
        // module actually wants the branch.
        for(auto const& branch:vBranchesToDeleteEarly) {
          branchToReadingWorker.insert(std::make_pair(branch, static_cast<Worker*>(nullptr)));
        }
      }
    }
  }

  // -----------------------------

  typedef std::vector<std::string> vstring;

  // -----------------------------

  StreamSchedule::StreamSchedule(std::shared_ptr<TriggerResultInserter> inserter,
                                 std::vector<edm::propagate_const<std::shared_ptr<PathStatusInserter>>>& pathStatusInserters,
                                 std::vector<edm::propagate_const<std::shared_ptr<EndPathStatusInserter>>>& endPathStatusInserters,
                                 std::shared_ptr<ModuleRegistry> modReg,
                                 ParameterSet& proc_pset,
                                 service::TriggerNamesService const& tns,
                                 PreallocationConfiguration const& prealloc,
                                 ProductRegistry& preg,
                                 BranchIDListHelper& branchIDListHelper,
                                 ExceptionToActionTable const& actions,
                                 std::shared_ptr<ActivityRegistry> areg,
                                 std::shared_ptr<ProcessConfiguration> processConfiguration,
                                 bool allowEarlyDelete,
                                 StreamID streamID,
                                 ProcessContext const* processContext) :
    workerManager_(modReg,areg, actions),
    actReg_(areg),
    results_(new HLTGlobalStatus(tns.getTrigPaths().size())),
    results_inserter_(),
    trig_paths_(),
    end_paths_(),
    total_events_(),
    total_passed_(),
    number_of_unscheduled_modules_(0),
    streamID_(streamID),
    streamContext_(streamID_, processContext),
    endpathsAreActive_(true),
    skippingEvent_(false){

    ParameterSet const& opts = proc_pset.getUntrackedParameterSet("options", ParameterSet());
    bool hasPath = false;
    std::vector<std::string> const& pathNames = tns.getTrigPaths();
    std::vector<std::string> const& endPathNames = tns.getEndPaths();

    int trig_bitpos = 0;
    trig_paths_.reserve(pathNames.size());
    for (auto const& trig_name : pathNames) {
      fillTrigPath(proc_pset, preg, &prealloc, processConfiguration, trig_bitpos, trig_name, results(), endPathNames);
      ++trig_bitpos;
      hasPath = true;
    }

    if (hasPath) {
      // the results inserter stands alone
      inserter->setTrigResultForStream(streamID.value(), results());

      results_inserter_ = makeInserter(actions, actReg_, inserter);
      addToAllWorkers(results_inserter_.get());
    }

    // fill normal endpaths
    int bitpos = 0;
    end_paths_.reserve(endPathNames.size());
    for (auto const& end_path_name : endPathNames) {
      fillEndPath(proc_pset, preg, &prealloc, processConfiguration, bitpos, end_path_name, endPathNames);
      ++bitpos;
    }

    makePathStatusInserters(pathStatusInserters, endPathStatusInserters, actions);

    //See if all modules were used
    std::set<std::string> usedWorkerLabels;
    for (auto const& worker : allWorkers()) {
      usedWorkerLabels.insert(worker->description().moduleLabel());
    }
    std::vector<std::string> modulesInConfig(proc_pset.getParameter<std::vector<std::string> >("@all_modules"));
    std::set<std::string> modulesInConfigSet(modulesInConfig.begin(), modulesInConfig.end());
    std::vector<std::string> unusedLabels;
    set_difference(modulesInConfigSet.begin(), modulesInConfigSet.end(),
                   usedWorkerLabels.begin(), usedWorkerLabels.end(),
                   back_inserter(unusedLabels));
    std::set<std::string> unscheduledLabels;
    std::vector<std::string>  shouldBeUsedLabels;
    if (!unusedLabels.empty()) {
      //Need to
      // 1) create worker
      // 2) if it is a WorkerT<EDProducer>, add it to our list
      // 3) hand list to our delayed reader
      for (auto const& label : unusedLabels) {
        bool isTracked;
        ParameterSet* modulePSet(proc_pset.getPSetForUpdate(label, isTracked));
        assert(isTracked);
        assert(modulePSet != nullptr);
        workerManager_.addToUnscheduledWorkers(*modulePSet, preg, &prealloc, processConfiguration, label, unscheduledLabels, shouldBeUsedLabels);
      }
      if (!shouldBeUsedLabels.empty()) {
        std::ostringstream unusedStream;
        unusedStream << "'" << shouldBeUsedLabels.front() << "'";
        for (std::vector<std::string>::iterator itLabel = shouldBeUsedLabels.begin() + 1,
              itLabelEnd = shouldBeUsedLabels.end();
            itLabel != itLabelEnd;
            ++itLabel) {
          unusedStream << ",'" << *itLabel << "'";
        }
        LogInfo("path")
          << "The following module labels are not assigned to any path:\n"
          << unusedStream.str()
          << "\n";
      }
    }
    if (!unscheduledLabels.empty()) {
      number_of_unscheduled_modules_=unscheduledLabels.size();
      workerManager_.setOnDemandProducts(preg, unscheduledLabels);
    }


    initializeEarlyDelete(*modReg, opts,preg,allowEarlyDelete);
    
  } // StreamSchedule::StreamSchedule

  
  void StreamSchedule::initializeEarlyDelete(ModuleRegistry & modReg,
                                             edm::ParameterSet const& opts, edm::ProductRegistry const& preg,
                                       bool allowEarlyDelete) {
    //for now, if have a subProcess, don't allow early delete
    // In the future we should use the SubProcess's 'keep list' to decide what can be kept
    if(not allowEarlyDelete)  return;

    //see if 'canDeleteEarly' was set and if so setup the list with those products actually
    // registered for this job
    std::multimap<std::string,Worker*> branchToReadingWorker;
    initializeBranchToReadingWorker(opts,preg,branchToReadingWorker);
    
    //If no delete early items have been specified we don't have to do anything
    if(branchToReadingWorker.empty()) {
      return;
    }
    const std::vector<std::string> kEmpty;
    std::map<Worker*,unsigned int> reserveSizeForWorker;
    unsigned int upperLimitOnReadingWorker =0;
    unsigned int upperLimitOnIndicies = 0;
    unsigned int nUniqueBranchesToDelete=branchToReadingWorker.size();
    
    //talk with output modules first
    modReg.forAllModuleHolders([&branchToReadingWorker,&nUniqueBranchesToDelete](maker::ModuleHolder* iHolder){
      auto comm = iHolder->createOutputModuleCommunicator();
      if (comm) {
        if(!branchToReadingWorker.empty()) {
          //If an OutputModule needs a product, we can't delete it early
          // so we should remove it from our list
          SelectedProductsForBranchType const& kept = comm->keptProducts();
          for(auto const& item: kept[InEvent]) {
            BranchDescription const& desc = *item.first;
            auto found = branchToReadingWorker.equal_range(desc.branchName());
            if(found.first !=found.second) {
              --nUniqueBranchesToDelete;
              branchToReadingWorker.erase(found.first,found.second);
            }
          }
        }
      }
    });
    
    if(branchToReadingWorker.empty()) {
      return;
    }
    
    for (auto w :allWorkers()) {
      //determine if this module could read a branch we want to delete early
      auto pset = pset::Registry::instance()->getMapped(w->description().parameterSetID());
      if(nullptr!=pset) {
        auto branches = pset->getUntrackedParameter<std::vector<std::string>>("mightGet",kEmpty);
        if(not branches.empty()) {
          ++upperLimitOnReadingWorker;
        }
        for(auto const& branch:branches){
          auto found = branchToReadingWorker.equal_range(branch);
          if(found.first != found.second) {
            ++upperLimitOnIndicies;
            ++reserveSizeForWorker[w];
            if(nullptr == found.first->second) {
              found.first->second = w;
            } else {
              branchToReadingWorker.insert(make_pair(found.first->first,w));
            }
          }
        }
      }
    }
    {
      auto it = branchToReadingWorker.begin();
      std::vector<std::string> unusedBranches;
      while(it !=branchToReadingWorker.end()) {
        if(it->second == nullptr) {
          unusedBranches.push_back(it->first);
          //erasing the object invalidates the iterator so must advance it first
          auto temp = it;
          ++it;
          branchToReadingWorker.erase(temp);
        } else {
          ++it;
        }
      }
      if(not unusedBranches.empty()) {
        LogWarning l("UnusedProductsForCanDeleteEarly");
        l<<"The following products in the 'canDeleteEarly' list are not used in this job and will be ignored.\n"
        " If possible, remove the producer from the job or add the product to the producer's own 'mightGet' list.";
        for(auto const& n:unusedBranches){
          l<<"\n "<<n;
        }
      }
    }  
    if(!branchToReadingWorker.empty()) {
      earlyDeleteHelpers_.reserve(upperLimitOnReadingWorker);
      earlyDeleteHelperToBranchIndicies_.resize(upperLimitOnIndicies,0);
      earlyDeleteBranchToCount_.reserve(nUniqueBranchesToDelete);
      std::map<const Worker*,EarlyDeleteHelper*> alreadySeenWorkers;
      std::string lastBranchName;
      size_t nextOpenIndex = 0;
      unsigned int* beginAddress = &(earlyDeleteHelperToBranchIndicies_.front());
      for(auto& branchAndWorker:branchToReadingWorker) {
        if(lastBranchName != branchAndWorker.first) {
          //have to put back the period we removed earlier in order to get the proper name
          BranchID bid(branchAndWorker.first+".");
          earlyDeleteBranchToCount_.emplace_back(bid,0U);
          lastBranchName = branchAndWorker.first;
        }
        auto found = alreadySeenWorkers.find(branchAndWorker.second);
        if(alreadySeenWorkers.end() == found) {
          //NOTE: we will set aside enough space in earlyDeleteHelperToBranchIndicies_ to accommodate
          // all the branches that might be read by this worker. However, initially we will only tell the
          // EarlyDeleteHelper about the first one. As additional branches are added via 'appendIndex' the
          // EarlyDeleteHelper will automatically advance its internal end pointer.
          size_t index = nextOpenIndex;
          size_t nIndices = reserveSizeForWorker[branchAndWorker.second];
          earlyDeleteHelperToBranchIndicies_[index]=earlyDeleteBranchToCount_.size()-1;
          earlyDeleteHelpers_.emplace_back(beginAddress+index,
                                           beginAddress+index+1,
                                           &earlyDeleteBranchToCount_);
          branchAndWorker.second->setEarlyDeleteHelper(&(earlyDeleteHelpers_.back()));
          alreadySeenWorkers.insert(std::make_pair(branchAndWorker.second,&(earlyDeleteHelpers_.back())));
          nextOpenIndex +=nIndices;
        } else {
          found->second->appendIndex(earlyDeleteBranchToCount_.size()-1);
        }
      }
      
      //Now we can compactify the earlyDeleteHelperToBranchIndicies_ since we may have over estimated the
      // space needed for each module
      auto itLast = earlyDeleteHelpers_.begin();
      for(auto it = earlyDeleteHelpers_.begin()+1;it != earlyDeleteHelpers_.end();++it) {
        if(itLast->end() != it->begin()) {
          //figure the offset for next Worker since it hasn't been moved yet so it has the original address
          unsigned int delta = it->begin()- itLast->end();
          it->shiftIndexPointers(delta);
          
          earlyDeleteHelperToBranchIndicies_.erase(earlyDeleteHelperToBranchIndicies_.begin()+
                                                   (itLast->end()-beginAddress),
                                                   earlyDeleteHelperToBranchIndicies_.begin()+
                                                   (it->begin()-beginAddress));
        }
        itLast = it;
      }
      earlyDeleteHelperToBranchIndicies_.erase(earlyDeleteHelperToBranchIndicies_.begin()+(itLast->end()-beginAddress),
                                               earlyDeleteHelperToBranchIndicies_.end());
      
      //now tell the paths about the deleters
      for(auto& p : trig_paths_) {
        p.setEarlyDeleteHelpers(alreadySeenWorkers);
      }
      for(auto& p : end_paths_) {
        p.setEarlyDeleteHelpers(alreadySeenWorkers);
      }
      resetEarlyDelete();
    }
  }

  void StreamSchedule::fillWorkers(ParameterSet& proc_pset,
                                   ProductRegistry& preg,
                                   PreallocationConfiguration const* prealloc,
                                   std::shared_ptr<ProcessConfiguration const> processConfiguration,
                                   std::string const& pathName,
                                   bool ignoreFilters,
                                   PathWorkers& out,
                                   std::vector<std::string> const& endPathNames) {
    vstring modnames = proc_pset.getParameter<vstring>(pathName);
    PathWorkers tmpworkers;

    unsigned int placeInPath = 0;
    for (auto const& name : modnames) {

      WorkerInPath::FilterAction filterAction = WorkerInPath::Normal;
      if (name[0] == '!')       filterAction = WorkerInPath::Veto;
      else if (name[0] == '-')  filterAction = WorkerInPath::Ignore;

      std::string moduleLabel = name;
      if (filterAction != WorkerInPath::Normal) moduleLabel.erase(0, 1);

      bool isTracked;
      ParameterSet* modpset = proc_pset.getPSetForUpdate(moduleLabel, isTracked);
      if (modpset == nullptr) {
        std::string pathType("endpath");
        if (!search_all(endPathNames, pathName)) {
          pathType = std::string("path");
        }
        throw Exception(errors::Configuration) <<
          "The unknown module label \"" << moduleLabel <<
          "\" appears in " << pathType << " \"" << pathName <<
          "\"\n please check spelling or remove that label from the path.";
      }
      assert(isTracked);

      Worker* worker = workerManager_.getWorker(*modpset, preg, prealloc, processConfiguration, moduleLabel);
      if (ignoreFilters && filterAction != WorkerInPath::Ignore && worker->moduleType()==Worker::kFilter) {
        // We have a filter on an end path, and the filter is not explicitly ignored.
        // See if the filter is allowed.
        std::vector<std::string> allowed_filters = proc_pset.getUntrackedParameter<vstring>("@filters_on_endpaths");
        if (!search_all(allowed_filters, worker->description().moduleName())) {
          // Filter is not allowed. Ignore the result, and issue a warning.
          filterAction = WorkerInPath::Ignore;
          LogWarning("FilterOnEndPath")
            << "The EDFilter '" << worker->description().moduleName() << "' with module label '" << moduleLabel << "' appears on EndPath '" << pathName << "'.\n"
            << "The return value of the filter will be ignored.\n"
            << "To suppress this warning, either remove the filter from the endpath,\n"
            << "or explicitly ignore it in the configuration by using cms.ignore().\n";
        }
      }
      tmpworkers.emplace_back(worker, filterAction, placeInPath);
      ++placeInPath;
    }

    out.swap(tmpworkers);
  }

  void StreamSchedule::fillTrigPath(ParameterSet& proc_pset,
                                    ProductRegistry& preg,
                                    PreallocationConfiguration const* prealloc,
                                    std::shared_ptr<ProcessConfiguration const> processConfiguration,
                                    int bitpos, std::string const& name, TrigResPtr trptr,
                                    std::vector<std::string> const& endPathNames) {
    PathWorkers tmpworkers;
    fillWorkers(proc_pset, preg, prealloc, processConfiguration, name, false, tmpworkers, endPathNames);

    // an empty path will cause an extra bit that is not used
    if (!tmpworkers.empty()) {
      trig_paths_.emplace_back(bitpos, name, tmpworkers, trptr, actionTable(), actReg_, &streamContext_, &skippingEvent_, PathContext::PathType::kPath);
    } else {
      empty_trig_paths_.push_back(bitpos);
    }
    for (WorkerInPath const& workerInPath : tmpworkers) {
      addToAllWorkers(workerInPath.getWorker());
    }
  }

  void StreamSchedule::fillEndPath(ParameterSet& proc_pset,
                                   ProductRegistry& preg,
                                   PreallocationConfiguration const* prealloc,
                                   std::shared_ptr<ProcessConfiguration const> processConfiguration,
                                   int bitpos, std::string const& name,
                                   std::vector<std::string> const& endPathNames) {
    PathWorkers tmpworkers;
    fillWorkers(proc_pset, preg, prealloc, processConfiguration, name, true, tmpworkers, endPathNames);

    if (!tmpworkers.empty()) {
      //EndPaths are not supposed to stop if SkipEvent type exception happens
      end_paths_.emplace_back(bitpos, name, tmpworkers, TrigResPtr(), actionTable(), actReg_, &streamContext_, nullptr, PathContext::PathType::kEndPath);
    } else {
      empty_end_paths_.push_back(bitpos);
    }
    for (WorkerInPath const& workerInPath : tmpworkers) {
      addToAllWorkers(workerInPath.getWorker());
    }
  }

  void StreamSchedule::beginStream() {
    workerManager_.beginStream(streamID_, streamContext_);
  }
  
  void StreamSchedule::endStream() {
    workerManager_.endStream(streamID_, streamContext_);
  }

  void StreamSchedule::replaceModule(maker::ModuleHolder* iMod,
                                    std::string const& iLabel) {
    Worker* found = nullptr;
    for (auto const& worker : allWorkers()) {
      if (worker->description().moduleLabel() == iLabel) {
        found = worker;
        break;
      }
    }
    if (nullptr == found) {
      return;
    }

    iMod->replaceModuleFor(found);
    found->beginStream(streamID_,streamContext_);
  }

  std::vector<ModuleDescription const*>
  StreamSchedule::getAllModuleDescriptions() const {
    std::vector<ModuleDescription const*> result;
    result.reserve(allWorkers().size());

    for (auto const& worker : allWorkers()) {
      ModuleDescription const* p = worker->descPtr();
      result.push_back(p);
    }
    return result;
  }
  
  void StreamSchedule::processOneEventAsync(WaitingTaskHolder iTask,
                                            EventPrincipal& ep,
                                            EventSetup const& es,
                                            ServiceToken const& serviceToken,
                                            std::vector<edm::propagate_const<std::shared_ptr<PathStatusInserter>>>& pathStatusInserters) {
    try {
      this->resetAll();

      using Traits = OccurrenceTraits<EventPrincipal, BranchActionStreamBegin>;
      
      Traits::setStreamContext(streamContext_, ep);
      //a service may want to communicate with another service
      ServiceRegistry::Operate guard(serviceToken);
      Traits::preScheduleSignal(actReg_.get(), &streamContext_);

      HLTPathStatus hltPathStatus(hlt::Pass, 0);
      for (int empty_trig_path : empty_trig_paths_) {
        results_->at(empty_trig_path) = hltPathStatus;
        pathStatusInserters[empty_trig_path]->setPathStatus(streamID_, hltPathStatus);
        std::exception_ptr except = pathStatusInserterWorkers_[empty_trig_path]->runModuleDirectly<OccurrenceTraits<EventPrincipal, BranchActionStreamBegin>>(
            ep, es, streamID_, ParentContext(&streamContext_), &streamContext_
        );
        if (except) {
          iTask.doneWaiting(except);
          return;
        }
      }
      for (int empty_end_path : empty_end_paths_) {
        std::exception_ptr except = endPathStatusInserterWorkers_[empty_end_path]->runModuleDirectly<OccurrenceTraits<EventPrincipal, BranchActionStreamBegin>>(
            ep, es, streamID_, ParentContext(&streamContext_), &streamContext_
        );
        if (except) {
          iTask.doneWaiting(except);
          return;
        }
      }
      
      // This call takes care of the unscheduled processing.
      workerManager_.setupOnDemandSystem(ep,es);
      
      ++total_events_;

      //use to give priorities on an error to ones from Paths
      auto pathErrorHolder = std::make_unique<std::atomic<std::exception_ptr*>>(nullptr);
      auto pathErrorPtr = pathErrorHolder.get();
      auto allPathsDone = make_waiting_task(tbb::task::allocate_root(),
                                            [iTask,this,serviceToken,pathError=std::move(pathErrorHolder)](std::exception_ptr const* iPtr) mutable
                                            {
                                              ServiceRegistry::Operate operate(serviceToken);
                                              
                                              std::exception_ptr ptr;
                                              if(pathError->load()) {
                                                ptr = *pathError->load();
                                                delete pathError->load();
                                              } 
                                              if( (not ptr) and iPtr) {
                                                ptr = *iPtr;
                                              }
                                              iTask.doneWaiting(finishProcessOneEvent(ptr));
                                            });
      //The holder guarantees that if the paths finish before the loop ends
      // that we do not start too soon. It also guarantees that the task will
      // run under that condition.
      WaitingTaskHolder allPathsHolder(allPathsDone);

      auto pathsDone = make_waiting_task(tbb::task::allocate_root(),
                                         [allPathsHolder,pathErrorPtr,&ep, &es, this,serviceToken](std::exception_ptr const* iPtr) mutable
                                            {
                                              ServiceRegistry::Operate operate(serviceToken);

                                              if(iPtr) {
                                                //this is used to prioritize this error over one
                                                // that happens in EndPath or Accumulate
                                                pathErrorPtr->store( new std::exception_ptr(*iPtr) );
                                              }
                                              finishedPaths(*pathErrorPtr, std::move(allPathsHolder), ep, es);
                                            });
      
      //The holder guarantees that if the paths finish before the loop ends
      // that we do not start too soon. It also guarantees that the task will
      // run under that condition.
      WaitingTaskHolder taskHolder(pathsDone);

      //start end paths first so on single threaded the paths will run first
      for(auto it = end_paths_.rbegin(), itEnd = end_paths_.rend();
          it != itEnd; ++it) {
        it->processOneOccurrenceAsync(allPathsDone,ep, es, serviceToken, streamID_, &streamContext_);
      }

      for(auto it = trig_paths_.rbegin(), itEnd = trig_paths_.rend();
          it != itEnd; ++ it) {
        it->processOneOccurrenceAsync(pathsDone,ep, es, serviceToken, streamID_, &streamContext_);
      }

      ParentContext parentContext(&streamContext_);
      workerManager_.processAccumulatorsAsync<OccurrenceTraits<EventPrincipal, BranchActionStreamBegin>>(
        allPathsDone, ep, es, serviceToken, streamID_, parentContext, &streamContext_);
    }catch (...) {
      iTask.doneWaiting(std::current_exception());
    }
  }
  
  void
  StreamSchedule::finishedPaths(std::atomic<std::exception_ptr*>& iExcept, WaitingTaskHolder iWait, EventPrincipal& ep,
                                EventSetup const& es) {
    
    if(iExcept) {
      try {
        std::rethrow_exception(*(iExcept.load()));
      }
      catch(cms::Exception& e) {
        exception_actions::ActionCodes action = actionTable().find(e.category());
        assert (action != exception_actions::IgnoreCompletely);
        assert (action != exception_actions::FailPath);
        if (action == exception_actions::SkipEvent) {
          edm::printCmsExceptionWarning("SkipEvent", e);
          *(iExcept.load()) = std::exception_ptr();
        } else {
          *(iExcept.load()) = std::current_exception();
        }
      }
      catch(...) {
        *(iExcept.load()) = std::current_exception();
      }
    }

    
    if((not iExcept) and results_->accept()) {
      ++total_passed_;
    }

    if(nullptr != results_inserter_.get()) {
      try {
        //Even if there was an exception, we need to allow results inserter
        // to run since some module may be waiting on its results.
        ParentContext parentContext(&streamContext_);
        using Traits = OccurrenceTraits<EventPrincipal, BranchActionStreamBegin>;

        results_inserter_->doWork<Traits>(ep, es, streamID_, parentContext, &streamContext_);
      }
      catch (cms::Exception & ex) {
        if (not iExcept) {
          if(ex.context().empty()) {
            std::ostringstream ost;
            ost << "Processing Event " << ep.id();
            ex.addContext(ost.str());
          }
          iExcept.store( new std::exception_ptr(std::current_exception()));
        }
      }
      catch(...) {
        if (not iExcept) {
          iExcept.store(new std::exception_ptr(std::current_exception()));
        }
      }
    }
    std::exception_ptr ptr;
    if(iExcept) {
      ptr = *iExcept.load();
    }
    iWait.doneWaiting(ptr);
  }

  
  std::exception_ptr
  StreamSchedule::finishProcessOneEvent(std::exception_ptr iExcept) {
    using Traits = OccurrenceTraits<EventPrincipal, BranchActionStreamBegin>;

    if(iExcept) {
      //add context information to the exception and print message
      try {
        convertException::wrap([&]() {
          std::rethrow_exception(iExcept);
        });
      } catch(cms::Exception& ex) {
        bool const cleaningUpAfterException = false;
        if (ex.context().empty()) {
          addContextAndPrintException("Calling function StreamSchedule::processOneEvent", ex, cleaningUpAfterException);
        } else {
          addContextAndPrintException("", ex, cleaningUpAfterException);
        }
        iExcept = std::current_exception();
      }

      actReg_->preStreamEarlyTerminationSignal_(streamContext_,TerminationOrigin::ExceptionFromThisContext);
    }
    
    try {
      Traits::postScheduleSignal(actReg_.get(), &streamContext_);
    } catch(...) {
      if(not iExcept) {
        iExcept = std::current_exception();
      }
    }
    if(not iExcept ) {
      resetEarlyDelete();
    }
    
    return iExcept;
  }

  void
  StreamSchedule::availablePaths(std::vector<std::string>& oLabelsToFill) const {
    oLabelsToFill.reserve(trig_paths_.size());
    std::transform(trig_paths_.begin(),
                   trig_paths_.end(),
                   std::back_inserter(oLabelsToFill),
                   std::bind(&Path::name, std::placeholders::_1));
  }

  void
  StreamSchedule::modulesInPath(std::string const& iPathLabel,
                          std::vector<std::string>& oLabelsToFill) const {
    TrigPaths::const_iterator itFound =
    std::find_if (trig_paths_.begin(),
                 trig_paths_.end(),
                 std::bind(std::equal_to<std::string>(),
                             iPathLabel,
                             std::bind(&Path::name, std::placeholders::_1)));
    if (itFound!=trig_paths_.end()) {
      oLabelsToFill.reserve(itFound->size());
      for (size_t i = 0; i < itFound->size(); ++i) {
        oLabelsToFill.push_back(itFound->getWorker(i)->description().moduleLabel());
      }
    }
  }

  void
  StreamSchedule::moduleDescriptionsInPath(std::string const& iPathLabel,
                                           std::vector<ModuleDescription const*>& descriptions,
                                           unsigned int hint) const {
    descriptions.clear();
    bool found = false;
    TrigPaths::const_iterator itFound;

    if(hint < trig_paths_.size()) {
      itFound = trig_paths_.begin() + hint;
      if(itFound->name() == iPathLabel) found = true;
    }
    if(!found) {
      // if the hint did not work, do it the slow way
      itFound = std::find_if (trig_paths_.begin(),
                              trig_paths_.end(),
                              std::bind(std::equal_to<std::string>(),
                                        iPathLabel,
                                        std::bind(&Path::name, std::placeholders::_1)));
      if (itFound != trig_paths_.end()) found = true;
    }
    if (found) {
      descriptions.reserve(itFound->size());
      for (size_t i = 0; i < itFound->size(); ++i) {
        descriptions.push_back(itFound->getWorker(i)->descPtr());
      }
    }
  }

  void
  StreamSchedule::moduleDescriptionsInEndPath(std::string const& iEndPathLabel,
                                              std::vector<ModuleDescription const*>& descriptions,
                                              unsigned int hint) const {
    descriptions.clear();
    bool found = false;
    TrigPaths::const_iterator itFound;

    if(hint < end_paths_.size()) {
      itFound = end_paths_.begin() + hint;
      if(itFound->name() == iEndPathLabel) found = true;
    }
    if(!found) {
      // if the hint did not work, do it the slow way
      itFound = std::find_if (end_paths_.begin(),
                              end_paths_.end(),
                              std::bind(std::equal_to<std::string>(),
                                        iEndPathLabel,
                                        std::bind(&Path::name, std::placeholders::_1)));
      if (itFound != end_paths_.end()) found = true;
    }
    if (found) {
      descriptions.reserve(itFound->size());
      for (size_t i = 0; i < itFound->size(); ++i) {
        descriptions.push_back(itFound->getWorker(i)->descPtr());
      }
    }
  }

  void
  StreamSchedule::enableEndPaths(bool active) {
    endpathsAreActive_ = active;
  }

  bool
  StreamSchedule::endPathsEnabled() const {
    return endpathsAreActive_;
  }

  static void
  fillModuleInPathSummary(Path const& path,
                          size_t which,
                          ModuleInPathSummary& sum) {
    sum.timesVisited += path.timesVisited(which);
    sum.timesPassed  += path.timesPassed(which);
    sum.timesFailed  += path.timesFailed(which);
    sum.timesExcept  += path.timesExcept(which);
    sum.moduleLabel  = path.getWorker(which)->description().moduleLabel();
  }

  static void
  fillPathSummary(Path const& path, PathSummary& sum) {
    sum.name        = path.name();
    sum.bitPosition = path.bitPosition();
    sum.timesRun    += path.timesRun();
    sum.timesPassed += path.timesPassed();
    sum.timesFailed += path.timesFailed();
    sum.timesExcept += path.timesExcept();
    
    Path::size_type sz = path.size();
    if(sum.moduleInPathSummaries.empty()) {
      std::vector<ModuleInPathSummary> temp(sz);
      for (size_t i = 0; i != sz; ++i) {
        fillModuleInPathSummary(path, i, temp[i]);
      }
      sum.moduleInPathSummaries.swap(temp);
    } else {
      assert(sz == sum.moduleInPathSummaries.size());
      for (size_t i = 0; i != sz; ++i) {
        fillModuleInPathSummary(path, i, sum.moduleInPathSummaries[i]);
      }
    }
  }

  static void
  fillWorkerSummaryAux(Worker const& w, WorkerSummary& sum) {
    sum.timesVisited += w.timesVisited();
    sum.timesRun     += w.timesRun();
    sum.timesPassed  += w.timesPassed();
    sum.timesFailed  += w.timesFailed();
    sum.timesExcept  += w.timesExcept();
    sum.moduleLabel  = w.description().moduleLabel();
  }

  static void
  fillWorkerSummary(Worker const* pw, WorkerSummary& sum) {
    fillWorkerSummaryAux(*pw, sum);
  }

  void
  StreamSchedule::getTriggerReport(TriggerReport& rep) const {
    rep.eventSummary.totalEvents += totalEvents();
    rep.eventSummary.totalEventsPassed += totalEventsPassed();
    rep.eventSummary.totalEventsFailed += totalEventsFailed();

    fill_summary(trig_paths_,  rep.trigPathSummaries, &fillPathSummary);
    fill_summary(end_paths_,   rep.endPathSummaries,  &fillPathSummary);
    fill_summary(allWorkers(), rep.workerSummaries,   &fillWorkerSummary);
  }

  void
  StreamSchedule::clearCounters() {
    using std::placeholders::_1;
    total_events_ = total_passed_ = 0;
    for_all(trig_paths_, std::bind(&Path::clearCounters, _1));
    for_all(end_paths_, std::bind(&Path::clearCounters, _1));
    for_all(allWorkers(), std::bind(&Worker::clearCounters, _1));
  }

  void
  StreamSchedule::resetAll() {
    skippingEvent_ = false;
    results_->reset();
  }

  void
  StreamSchedule::addToAllWorkers(Worker* w) {
    workerManager_.addToAllWorkers(w);
  }

  void 
  StreamSchedule::resetEarlyDelete() {
    //must be sure we have cleared the count first
    for(auto& count:earlyDeleteBranchToCount_) {
      count.count = 0;
    }
    //now reset based on how many helpers use that branch
    for(auto& index: earlyDeleteHelperToBranchIndicies_) {
      ++(earlyDeleteBranchToCount_[index].count);
    }
    for(auto& helper: earlyDeleteHelpers_) {
      helper.reset();
    }
  }

  void
  StreamSchedule::makePathStatusInserters(
      std::vector<edm::propagate_const<std::shared_ptr<PathStatusInserter>>>& pathStatusInserters,
      std::vector<edm::propagate_const<std::shared_ptr<EndPathStatusInserter>>>& endPathStatusInserters,
      ExceptionToActionTable const& actions) {

    int bitpos = 0;
    unsigned int indexEmpty = 0;
    unsigned int indexOfPath = 0;
    for(auto & pathStatusInserter : pathStatusInserters) {
      std::shared_ptr<PathStatusInserter> inserterPtr = get_underlying(pathStatusInserter);
      WorkerPtr workerPtr(new edm::WorkerT<PathStatusInserter::ModuleType>(inserterPtr,
                                                                           inserterPtr->moduleDescription(),
                                                                           &actions));
      pathStatusInserterWorkers_.emplace_back(workerPtr);
      workerPtr->setActivityRegistry(actReg_);
      addToAllWorkers(workerPtr.get());

      // A little complexity here because a C++ Path object is not
      // instantiated and put into end_paths if there are no modules
      // on the configured path.
      if (indexEmpty < empty_trig_paths_.size() && bitpos == empty_trig_paths_.at(indexEmpty)) {
        ++indexEmpty;
      } else {
        trig_paths_.at(indexOfPath).setPathStatusInserter(inserterPtr.get(),
                                                          workerPtr.get());
        ++indexOfPath;
      }
      ++bitpos;
    }

    bitpos = 0;
    indexEmpty = 0;
    indexOfPath = 0;
    for(auto & endPathStatusInserter : endPathStatusInserters) {
      std::shared_ptr<EndPathStatusInserter> inserterPtr = get_underlying(endPathStatusInserter);
      WorkerPtr workerPtr(new edm::WorkerT<EndPathStatusInserter::ModuleType>(inserterPtr,
                                                                              inserterPtr->moduleDescription(),
                                                                              &actions));
      endPathStatusInserterWorkers_.emplace_back(workerPtr);
      workerPtr->setActivityRegistry(actReg_);
      addToAllWorkers(workerPtr.get());

      // A little complexity here because a C++ Path object is not
      // instantiated and put into end_paths if there are no modules
      // on the configured path.
      if (indexEmpty < empty_end_paths_.size() && bitpos == empty_end_paths_.at(indexEmpty)) {
        ++indexEmpty;
      } else {
        end_paths_.at(indexOfPath).setPathStatusInserter(nullptr,
                                                         workerPtr.get());
        ++indexOfPath;
      }
      ++bitpos;
    }
  }
}