llvm-project/compiler-rt/lib/tsan/rtl/tsan_clock.h

101 lines
2.2 KiB
C++

//===-- tsan_clock.h --------------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is a part of ThreadSanitizer (TSan), a race detector.
//
//===----------------------------------------------------------------------===//
#ifndef TSAN_CLOCK_H
#define TSAN_CLOCK_H
#include "tsan_defs.h"
#include "tsan_vector.h"
namespace __tsan {
struct ClockElem {
u64 epoch : kClkBits;
u64 reused : 64 - kClkBits;
};
// The clock that lives in sync variables (mutexes, atomics, etc).
class SyncClock {
public:
SyncClock();
uptr size() const {
return clk_.Size();
}
u64 get(unsigned tid) const {
DCHECK_LT(tid, clk_.Size());
return clk_[tid].epoch;
}
void Reset();
void DebugDump(int(*printf)(const char *s, ...));
private:
unsigned release_store_tid_;
unsigned release_store_reused_;
static const uptr kDirtyTids = 2;
unsigned dirty_tids_[kDirtyTids];
mutable Vector<ClockElem> clk_;
friend struct ThreadClock;
};
// The clock that lives in threads.
struct ThreadClock {
public:
explicit ThreadClock(unsigned tid, unsigned reused = 0);
u64 get(unsigned tid) const {
DCHECK_LT(tid, kMaxTidInClock);
return clk_[tid].epoch;
}
void set(unsigned tid, u64 v);
void set(u64 v) {
DCHECK_GE(v, clk_[tid_].epoch);
clk_[tid_].epoch = v;
}
void tick() {
clk_[tid_].epoch++;
}
uptr size() const {
return nclk_;
}
void acquire(const SyncClock *src);
void release(SyncClock *dst) const;
void acq_rel(SyncClock *dst);
void ReleaseStore(SyncClock *dst) const;
void DebugReset();
void DebugDump(int(*printf)(const char *s, ...));
private:
static const uptr kDirtyTids = SyncClock::kDirtyTids;
const unsigned tid_;
const unsigned reused_;
u64 last_acquire_;
uptr nclk_;
ClockElem clk_[kMaxTidInClock];
bool IsAlreadyAcquired(const SyncClock *src) const;
void UpdateCurrentThread(SyncClock *dst) const;
};
} // namespace __tsan
#endif // TSAN_CLOCK_H