queued.hh

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#ifndef __MEM_CACHE_PREFETCH_QUEUED_HH__
#define __MEM_CACHE_PREFETCH_QUEUED_HH__
 
#include <cstdint>
#include <list>
#include <utility>
 
#include "arch/generic/mmu.hh"
#include "base/statistics.hh"
#include "base/types.hh"
#include "mem/cache/prefetch/base.hh"
#include "mem/packet.hh"
 
namespace gem5
{
 
struct QueuedPrefetcherParams;
 
namespace prefetch
{
 
class Queued : public Base
{
  protected:
    struct DeferredPacket : public BaseMMU::Translation
    {
        Queued *owner;
        PrefetchInfo pfInfo;
        Tick tick;
        PacketPtr pkt;
        int32_t priority;
        RequestPtr translationRequest;
        ThreadContext *tc;
        bool ongoingTranslation;
        const CacheAccessor *cache;
 
        DeferredPacket(Queued *o, PrefetchInfo const &pfi, Tick t,
            int32_t prio, const CacheAccessor &_cache)
            : owner(o), pfInfo(pfi), tick(t), pkt(nullptr),
            priority(prio), translationRequest(), tc(nullptr),
            ongoingTranslation(false), cache(&_cache) {
        }
 
        bool operator>(const DeferredPacket& that) const
        {
            return priority > that.priority;
        }
        bool operator<(const DeferredPacket& that) const
        {
            return priority < that.priority;
        }
        bool operator<=(const DeferredPacket& that) const
        {
            return !(*this > that);
        }
 
        void createPkt(Addr paddr, unsigned blk_size, RequestorID requestor_id,
                       bool tag_prefetch, Tick t);
 
        void setTranslationRequest(const RequestPtr &req)
        {
            translationRequest = req;
        }
 
        void markDelayed() override
        {}
 
        void finish(const Fault &fault, const RequestPtr &req,
                            ThreadContext *tc, BaseMMU::Mode mode) override;
 
        void startTranslation(BaseMMU *mmu);
    };
 
    std::list<DeferredPacket> pfq;
    std::list<DeferredPacket> pfqMissingTranslation;
 
    using const_iterator = std::list<DeferredPacket>::const_iterator;
    using iterator = std::list<DeferredPacket>::iterator;
 
    // PARAMETERS
 
    const unsigned queueSize;
 
    const unsigned missingTranslationQueueSize;
 
    const Cycles latency;
 
    const bool queueSquash;
 
    const bool queueFilter;
 
    const bool cacheSnoop;
 
    const bool tagPrefetch;
 
    const unsigned int throttleControlPct;
 
    struct QueuedStats : public statistics::Group
    {
        QueuedStats(statistics::Group *parent);
        // STATS
        statistics::Scalar pfIdentified;
        statistics::Scalar pfBufferHit;
        statistics::Scalar pfInCache;
        statistics::Scalar pfRemovedDemand;
        statistics::Scalar pfRemovedFull;
        statistics::Scalar pfSpanPage;
        statistics::Scalar pfUsefulSpanPage;
    } statsQueued;
  public:
    using AddrPriority = std::pair<Addr, int32_t>;
 
    Queued(const QueuedPrefetcherParams &p);
    virtual ~Queued();
 
    void
    notify(const CacheAccessProbeArg &acc, const PrefetchInfo &pfi) override;
 
    void insert(const PacketPtr &pkt, PrefetchInfo &new_pfi, int32_t priority,
                const CacheAccessor &cache);
 
    virtual void calculatePrefetch(const PrefetchInfo &pfi,
                                   std::vector<AddrPriority> &addresses,
                                   const CacheAccessor &cache) = 0;
    PacketPtr getPacket() override;
 
    Tick nextPrefetchReadyTime() const override
    {
        return pfq.empty() ? MaxTick : pfq.front().tick;
    }
 
    void printQueue(const std::list<DeferredPacket> &queue) const;
 
  private:
 
    void addToQueue(std::list<DeferredPacket> &queue, DeferredPacket &dpp);
 
    void processMissingTranslations(unsigned max);
 
    void translationComplete(DeferredPacket *dp, bool failed,
                             const CacheAccessor &cache);
 
    bool alreadyInQueue(std::list<DeferredPacket> &queue,
                        const PrefetchInfo &pfi, int32_t priority);
 
    size_t getMaxPermittedPrefetches(size_t total) const;
 
    RequestPtr createPrefetchRequest(Addr addr, PrefetchInfo const &pfi,
                                        PacketPtr pkt);
};
 
} // namespace prefetch
} // namespace gem5
 
#endif //__MEM_CACHE_PREFETCH_QUEUED_HH__