base.hh

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#ifndef __MEM_CACHE_TAGS_BASE_HH__
#define __MEM_CACHE_TAGS_BASE_HH__
 
#include <cassert>
#include <cstdint>
#include <functional>
#include <string>
 
#include "base/callback.hh"
#include "base/logging.hh"
#include "base/statistics.hh"
#include "base/types.hh"
#include "mem/cache/cache_blk.hh"
#include "mem/packet.hh"
#include "params/BaseTags.hh"
#include "sim/clocked_object.hh"
 
namespace gem5
{
 
class System;
class IndexingPolicy;
class ReplaceableEntry;
 
class BaseTags : public ClockedObject
{
  protected:
    const unsigned blkSize;
    const Addr blkMask;
    const unsigned size;
    const Cycles lookupLatency;
 
    System *system;
 
    BaseIndexingPolicy *indexingPolicy;
 
    const unsigned warmupBound;
    bool warmedUp;
 
    const unsigned numBlocks;
 
    std::unique_ptr<uint8_t[]> dataBlks;
 
    struct BaseTagStats : public statistics::Group
    {
        BaseTagStats(BaseTags &tags);
 
        void regStats() override;
        void preDumpStats() override;
 
        BaseTags &tags;
 
        statistics::Average tagsInUse;
 
        statistics::Scalar totalRefs;
 
        statistics::Scalar sampledRefs;
 
        statistics::Formula avgRefs;
 
        statistics::Scalar warmupTick;
 
        statistics::AverageVector occupancies;
 
        statistics::Formula avgOccs;
 
        statistics::Vector occupanciesTaskId;
 
        statistics::Vector2d ageTaskId;
 
        statistics::Formula ratioOccsTaskId;
 
        statistics::Scalar tagAccesses;
        statistics::Scalar dataAccesses;
    } stats;
 
  public:
    typedef BaseTagsParams Params;
    BaseTags(const Params &p);
 
    virtual ~BaseTags() {}
 
    virtual void tagsInit() = 0;
 
    void cleanupRefs();
 
    void computeStats();
 
    std::string print();
 
    virtual CacheBlk *findBlock(Addr addr, bool is_secure) const;
 
    virtual ReplaceableEntry* findBlockBySetAndWay(int set, int way) const;
 
    Addr blkAlign(Addr addr) const
    {
        return addr & ~blkMask;
    }
 
    int extractBlkOffset(Addr addr) const
    {
        return (addr & blkMask);
    }
 
    virtual void setWayAllocationMax(int ways)
    {
        panic("This tag class does not implement way allocation limit!\n");
    }
 
    virtual int getWayAllocationMax() const
    {
        panic("This tag class does not implement way allocation limit!\n");
        return -1;
    }
 
    virtual void invalidate(CacheBlk *blk)
    {
        assert(blk);
        assert(blk->isValid());
 
        stats.occupancies[blk->getSrcRequestorId()]--;
        stats.totalRefs += blk->getRefCount();
        stats.sampledRefs++;
 
        blk->invalidate();
    }
 
    virtual CacheBlk* findVictim(Addr addr, const bool is_secure,
                                 const std::size_t size,
                                 std::vector<CacheBlk*>& evict_blks) = 0;
 
    virtual CacheBlk* accessBlock(const PacketPtr pkt, Cycles &lat) = 0;
 
    virtual Addr extractTag(const Addr addr) const;
 
    virtual void insertBlock(const PacketPtr pkt, CacheBlk *blk);
 
    virtual void moveBlock(CacheBlk *src_blk, CacheBlk *dest_blk);
 
    virtual Addr regenerateBlkAddr(const CacheBlk* blk) const = 0;
 
    virtual void forEachBlk(std::function<void(CacheBlk &)> visitor) = 0;
 
    virtual bool anyBlk(std::function<bool(CacheBlk &)> visitor) = 0;
 
  private:
    void cleanupRefsVisitor(CacheBlk &blk);
 
    void computeStatsVisitor(CacheBlk &blk);
};
 
} // namespace gem5
 
#endif //__MEM_CACHE_TAGS_BASE_HH__