gem5  v22.1.0.0
multi.cc
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37 
39 
40 #include "params/MultiPrefetcher.hh"
41 
42 namespace gem5
43 {
44 
46 namespace prefetch
47 {
48 
49 Multi::Multi(const MultiPrefetcherParams &p)
50  : Base(p),
51  prefetchers(p.prefetchers.begin(), p.prefetchers.end()),
52  lastChosenPf(0)
53 {
54 }
55 
56 void
58 {
59  for (auto pf : prefetchers)
60  pf->setCache(_cache);
61 }
62 
63 Tick
65 {
66  Tick next_ready = MaxTick;
67 
68  for (auto pf : prefetchers)
69  next_ready = std::min(next_ready, pf->nextPrefetchReadyTime());
70 
71  return next_ready;
72 }
73 
76 {
77  lastChosenPf = (lastChosenPf + 1) % prefetchers.size();
78  uint8_t pf_turn = lastChosenPf;
79 
80  for (int pf = 0 ; pf < prefetchers.size(); pf++) {
81  if (prefetchers[pf_turn]->nextPrefetchReadyTime() <= curTick()) {
82  PacketPtr pkt = prefetchers[pf_turn]->getPacket();
83  panic_if(!pkt, "Prefetcher is ready but didn't return a packet.");
86  return pkt;
87  }
88  pf_turn = (pf_turn + 1) % prefetchers.size();
89  }
90 
91  return nullptr;
92 }
93 
94 } // namespace prefetch
95 } // namespace gem5
A basic cache interface.
Definition: base.hh:96
A Packet is used to encapsulate a transfer between two objects in the memory system (e....
Definition: packet.hh:294
uint64_t issuedPrefetches
Total prefetches issued.
Definition: base.hh:363
gem5::prefetch::Base::StatGroup prefetchStats
PacketPtr getPacket() override
Definition: multi.cc:75
void setCache(BaseCache *_cache) override
Definition: multi.cc:57
uint8_t lastChosenPf
Definition: multi.hh:76
Multi(const MultiPrefetcherParams &p)
Definition: multi.cc:49
std::vector< Base * > prefetchers
List of sub-prefetchers ordered by priority.
Definition: multi.hh:70
Tick nextPrefetchReadyTime() const override
Definition: multi.cc:64
#define panic_if(cond,...)
Conditional panic macro that checks the supplied condition and only panics if the condition is true a...
Definition: logging.hh:204
Bitfield< 54 > p
Definition: pagetable.hh:70
Bitfield< 2 > pf
Definition: misc.hh:555
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
Tick curTick()
The universal simulation clock.
Definition: cur_tick.hh:46
uint64_t Tick
Tick count type.
Definition: types.hh:58
const Tick MaxTick
Definition: types.hh:60
GEM5_DEPRECATED_NAMESPACE(GuestABI, guest_abi)
statistics::Scalar pfIssued
Definition: base.hh:335

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