multi.cc

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#include "mem/cache/prefetch/multi.hh"
 
#include "params/MultiPrefetcher.hh"
 
namespace gem5
{
 
namespace prefetch
{
 
Multi::Multi(const MultiPrefetcherParams &p)
  : Base(p),
    prefetchers(p.prefetchers.begin(), p.prefetchers.end()),
    lastChosenPf(0)
{
}
 
void
Multi::setCache(BaseCache *_cache)
{
    for (auto pf : prefetchers)
        pf->setCache(_cache);
}
 
Tick
Multi::nextPrefetchReadyTime() const
{
    Tick next_ready = MaxTick;
 
    for (auto pf : prefetchers)
        next_ready = std::min(next_ready, pf->nextPrefetchReadyTime());
 
    return next_ready;
}
 
PacketPtr
Multi::getPacket()
{
    lastChosenPf = (lastChosenPf + 1) % prefetchers.size();
    uint8_t pf_turn = lastChosenPf;
 
    for (int pf = 0 ;  pf < prefetchers.size(); pf++) {
        if (prefetchers[pf_turn]->nextPrefetchReadyTime() <= curTick()) {
            PacketPtr pkt = prefetchers[pf_turn]->getPacket();
            panic_if(!pkt, "Prefetcher is ready but didn't return a packet.");
            prefetchStats.pfIssued++;
            issuedPrefetches++;
            return pkt;
        }
        pf_turn = (pf_turn + 1) % prefetchers.size();
    }
 
    return nullptr;
}
 
} // namespace prefetch
} // namespace gem5