1//===-- tsan_mutexset.h -----------------------------------------*- C++ -*-===// 2// 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4// See https://llvm.org/LICENSE.txt for license information. 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6// 7//===----------------------------------------------------------------------===// 8// 9// This file is a part of ThreadSanitizer (TSan), a race detector. 10// 11// MutexSet holds the set of mutexes currently held by a thread. 12//===----------------------------------------------------------------------===// 13#ifndef TSAN_MUTEXSET_H 14#define TSAN_MUTEXSET_H 15 16#include "tsan_defs.h" 17 18namespace __tsan { 19 20class MutexSet { 21 public: 22 // Holds limited number of mutexes. 23 // The oldest mutexes are discarded on overflow. 24 static const uptr kMaxSize = 16; 25 struct Desc { 26 u64 id; 27 u64 epoch; 28 int count; 29 bool write; 30 }; 31 32 MutexSet(); 33 // The 'id' is obtained from SyncVar::GetId(). 34 void Add(u64 id, bool write, u64 epoch); 35 void Del(u64 id, bool write); 36 void Remove(u64 id); // Removes the mutex completely (if it's destroyed). 37 uptr Size() const; 38 Desc Get(uptr i) const; 39 40 void operator=(const MutexSet &other) { 41 internal_memcpy(this, &other, sizeof(*this)); 42 } 43 44 private: 45#if !SANITIZER_GO 46 uptr size_; 47 Desc descs_[kMaxSize]; 48#endif 49 50 void RemovePos(uptr i); 51 MutexSet(const MutexSet&); 52}; 53 54// Go does not have mutexes, so do not spend memory and time. 55// (Go sync.Mutex is actually a semaphore -- can be unlocked 56// in different goroutine). 57#if SANITIZER_GO 58MutexSet::MutexSet() {} 59void MutexSet::Add(u64 id, bool write, u64 epoch) {} 60void MutexSet::Del(u64 id, bool write) {} 61void MutexSet::Remove(u64 id) {} 62void MutexSet::RemovePos(uptr i) {} 63uptr MutexSet::Size() const { return 0; } 64MutexSet::Desc MutexSet::Get(uptr i) const { return Desc(); } 65#endif 66 67} // namespace __tsan 68 69#endif // TSAN_MUTEXSET_H 70