q_policy.hh

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#ifndef __MEM_QOS_Q_POLICY_HH__
#define __MEM_QOS_Q_POLICY_HH__
 
#include <deque>
#include <list>
#include <unordered_set>
 
#include "base/compiler.hh"
#include "mem/packet.hh"
#include "mem/qos/mem_ctrl.hh"
#include "params/QoSMemCtrl.hh"
 
namespace gem5
{
 
namespace memory
{
 
namespace qos
{
 
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<RequestorID> toServe;
};
 
} // namespace qos
} // namespace memory
} // namespace gem5
 
#endif /* __MEM_QOS_Q_POLICY_HH__ */