gem5  v21.1.0.2
barrier.hh
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37 
38 #ifndef __BASE_BARRIER_HH__
39 #define __BASE_BARRIER_HH__
40 
41 #include <condition_variable>
42 
43 namespace gem5
44 {
45 
46 class Barrier
47 {
48  private:
50  std::mutex bMutex;
52  std::condition_variable bCond;
54  unsigned numWaiting;
56  unsigned generation;
58  unsigned numLeft;
59 
60  public:
61  Barrier(unsigned _numWaiting)
62  : numWaiting(_numWaiting), generation(0), numLeft(_numWaiting)
63  {}
64 
65  bool
66  wait()
67  {
68  std::unique_lock<std::mutex> lock(bMutex);
69  unsigned int gen = generation;
70 
71  if (--numLeft == 0) {
72  generation++;
74  bCond.notify_all();
75  return true;
76  }
77  while (gen == generation)
78  bCond.wait(lock);
79  return false;
80  }
81 };
82 
83 } // namespace gem5
84 
85 #endif // __BASE_BARRIER_HH__
gem5::Barrier::wait
bool wait()
Definition: barrier.hh:66
gem5::Barrier::bCond
std::condition_variable bCond
Condition variable for waiting on barrier.
Definition: barrier.hh:52
gem5::Barrier::numLeft
unsigned numLeft
Number of threads remaining for the current generation.
Definition: barrier.hh:58
gem5::X86ISA::lock
Bitfield< 5 > lock
Definition: types.hh:82
gem5::Barrier::bMutex
std::mutex bMutex
Mutex to protect access to numLeft and generation.
Definition: barrier.hh:50
gem5::Barrier::generation
unsigned generation
Generation of this barrier.
Definition: barrier.hh:56
gem5::Barrier::Barrier
Barrier(unsigned _numWaiting)
Definition: barrier.hh:61
gem5::Barrier::numWaiting
unsigned numWaiting
Number of threads we should be waiting for before completing the barrier.
Definition: barrier.hh:54
gem5::Barrier
Definition: barrier.hh:46
gem5
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
Definition: decoder.cc:40

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