1//===-- tsan_mutexset.h -----------------------------------------*- C++ -*-===//
2//
3// This file is distributed under the University of Illinois Open Source
4// License. See LICENSE.TXT for details.
5//
6//===----------------------------------------------------------------------===//
7//
8// This file is a part of ThreadSanitizer (TSan), a race detector.
9//
10// MutexSet holds the set of mutexes currently held by a thread.
11//===----------------------------------------------------------------------===//
12#ifndef TSAN_MUTEXSET_H
13#define TSAN_MUTEXSET_H
14
15#include "tsan_defs.h"
16
17namespace __tsan {
18
19class MutexSet {
20 public:
21  // Holds limited number of mutexes.
22  // The oldest mutexes are discarded on overflow.
23  static const uptr kMaxSize = 16;
24  struct Desc {
25    u64 id;
26    u64 epoch;
27    int count;
28    bool write;
29  };
30
31  MutexSet();
32  // The 'id' is obtained from SyncVar::GetId().
33  void Add(u64 id, bool write, u64 epoch);
34  void Del(u64 id, bool write);
35  void Remove(u64 id);  // Removes the mutex completely (if it's destroyed).
36  uptr Size() const;
37  Desc Get(uptr i) const;
38
39  void operator=(const MutexSet &other) {
40    internal_memcpy(this, &other, sizeof(*this));
41  }
42
43 private:
44#if !SANITIZER_GO
45  uptr size_;
46  Desc descs_[kMaxSize];
47#endif
48
49  void RemovePos(uptr i);
50  MutexSet(const MutexSet&);
51};
52
53// Go does not have mutexes, so do not spend memory and time.
54// (Go sync.Mutex is actually a semaphore -- can be unlocked
55// in different goroutine).
56#if SANITIZER_GO
57MutexSet::MutexSet() {}
58void MutexSet::Add(u64 id, bool write, u64 epoch) {}
59void MutexSet::Del(u64 id, bool write) {}
60void MutexSet::Remove(u64 id) {}
61void MutexSet::RemovePos(uptr i) {}
62uptr MutexSet::Size() const { return 0; }
63MutexSet::Desc MutexSet::Get(uptr i) const { return Desc(); }
64#endif
65
66}  // namespace __tsan
67
68#endif  // TSAN_MUTEXSET_H
69