scheduler_mtapi.h

/*
 * Copyright (c) 2014-2016, Siemens AG. All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
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 * 2. Redistributions in binary form must reproduce the above copyright notice,
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 * and/or other materials provided with the distribution.
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#ifndef EMBB_DATAFLOW_INTERNAL_SCHEDULER_MTAPI_H_
#define EMBB_DATAFLOW_INTERNAL_SCHEDULER_MTAPI_H_

#include <embb/dataflow/internal/action.h>
#include <embb/dataflow/internal/scheduler.h>
#include <embb/tasks/node.h>
#include <embb/base/function.h>

#include <algorithm>

namespace embb {
namespace dataflow {
namespace internal {

class SchedulerMTAPI : public Scheduler {
 public:
  explicit SchedulerMTAPI(int slices)
    : slices_(slices) {
    embb::tasks::Node & node = embb::tasks::Node::GetInstance();

    int tl = std::min(
      static_cast<int>(node.GetTaskLimit()),
      static_cast<int>(node.GetGroupCount()));
    if (tl < slices_) {
      slices_ = tl;
    }

    group_ = reinterpret_cast<embb::tasks::Group**>(
      embb::base::Allocation::Allocate(
      sizeof(embb::tasks::Group*)*slices_));

    for (int ii = 0; ii < slices_; ii++) {
      embb::tasks::Group & group = node.CreateGroup();
      group_[ii] = &group;
    }

    queue_count_ = std::min(
      static_cast<int>(node.GetQueueCount()),
      static_cast<int>(node.GetWorkerThreadCount()) );
    queue_ = reinterpret_cast<embb::tasks::Queue**>(
      embb::base::Allocation::Allocate(
      sizeof(embb::tasks::Queue*)*queue_count_));

    for (int ii = 0; ii < queue_count_; ii++) {
      embb::tasks::Queue & queue = node.CreateQueue(0, true);
      queue_[ii] = &queue;
    }
  }
  virtual ~SchedulerMTAPI() {
    if (embb::tasks::Node::IsInitialized()) {
      // only destroy groups and queues if there still is an instance
      embb::tasks::Node & node = embb::tasks::Node::GetInstance();
      for (int ii = 0; ii < slices_; ii++) {
        group_[ii]->WaitAll(MTAPI_INFINITE);
        node.DestroyGroup(*group_[ii]);
      }
      for (int ii = 0; ii < queue_count_; ii++) {
        node.DestroyQueue(*queue_[ii]);
      }
    }
    embb::base::Allocation::Free(group_);
    embb::base::Allocation::Free(queue_);
  }
  virtual void Spawn(Action & action) {
    const int idx = action.GetClock() % slices_;
    group_[idx]->Spawn(embb::base::MakeFunction(action, &Action::RunMTAPI));
  }
  virtual void Enqueue(int process_id, Action & action) {
    const int idx = action.GetClock() % slices_;
    const int queue_id = process_id % queue_count_;
    queue_[queue_id]->Spawn(group_[idx],
      embb::base::MakeFunction(action, &Action::RunMTAPI));
  }
  virtual void WaitForSlice(int slice) {
    group_[slice]->WaitAll(MTAPI_INFINITE);
  }
  virtual int GetSlices() { return slices_; }
 private:
  embb::tasks::Group ** group_;
  embb::tasks::Queue ** queue_;
  int queue_count_;
  int slices_;
};

} // namespace internal
} // namespace dataflow
} // namespace embb

#endif // EMBB_DATAFLOW_INTERNAL_SCHEDULER_MTAPI_H_