q_policy.hh

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 * Author: Matteo Andreozzi
 */

#ifndef __MEM_QOS_Q_POLICY_HH__
#define __MEM_QOS_Q_POLICY_HH__

#include <deque>
#include <unordered_set>

#include "mem/packet.hh"
#include "params/QoSMemCtrl.hh"

namespace QoS {

class MemCtrl;

class QueuePolicy
{
  public:
    typedef std::deque<PacketPtr> PacketQueue;

    static QueuePolicy* create(const QoSMemCtrlParams* p);

    virtual void enqueuePacket(PacketPtr pkt) {};

    virtual PacketQueue::iterator selectPacket(PacketQueue* queue) = 0;

    void setMemCtrl(MemCtrl* mem) { memCtrl = mem; };

    virtual ~QueuePolicy() {};

  protected:
    QueuePolicy(const QoSMemCtrlParams* p)
      : memCtrl(nullptr)
    {}

    MemCtrl* memCtrl;
};

class LifoQueuePolicy : public QueuePolicy
{
  public:
    LifoQueuePolicy(const QoSMemCtrlParams* p)
      : QueuePolicy(p)
    {}

    PacketQueue::iterator
    selectPacket(PacketQueue* queue) override
    {
        return queue->end();
    }
};

class FifoQueuePolicy : public QueuePolicy
{
  public:
    FifoQueuePolicy(const QoSMemCtrlParams* p)
      : QueuePolicy(p)
    {}

    PacketQueue::iterator
    selectPacket(PacketQueue* queue) override
    {
        return queue->begin();
    }
};

class LrgQueuePolicy : public QueuePolicy
{
  public:
    LrgQueuePolicy(const QoSMemCtrlParams* p)
      : QueuePolicy(p)
    {}

    void enqueuePacket(PacketPtr pkt) override;

    PacketQueue::iterator
    selectPacket(PacketQueue* queue) override;

  protected:
    std::list<MasterID> toServe;
};

} // namespace QoS

#endif /* __MEM_QOS_Q_POLICY_HH__ */