mshr_queue.hh

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 * Authors: Erik Hallnor
 *          Andreas Sandberg
 */

#ifndef __MEM_CACHE_MSHR_QUEUE_HH__
#define __MEM_CACHE_MSHR_QUEUE_HH__

#include <string>

#include "base/types.hh"
#include "mem/cache/mshr.hh"
#include "mem/cache/queue.hh"
#include "mem/packet.hh"

class MSHRQueue : public Queue<MSHR>
{
  private:

    const int demandReserve;

  public:

    MSHRQueue(const std::string &_label, int num_entries, int reserve,
              int demand_reserve);

    MSHR *allocate(Addr blk_addr, unsigned blk_size, PacketPtr pkt,
                   Tick when_ready, Counter order, bool alloc_on_fill);

    void moveToFront(MSHR *mshr);

    void delay(MSHR *mshr, Tick delay_ticks);

    void markInService(MSHR *mshr, bool pending_modified_resp);

    void markPending(MSHR *mshr);

    bool forceDeallocateTarget(MSHR *mshr);

    bool havePending() const
    {
        return !readyList.empty();
    }

    bool canPrefetch() const
    {
        // @todo we may want to revisit the +1, currently added to
        // keep regressions unchanged
        return (allocated < numEntries - (numReserve + 1 + demandReserve));
    }
};

#endif //__MEM_CACHE_MSHR_QUEUE_HH__