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| #include "test.h"
#include <atomic>
#include <vector>
#include <sanitizer/tsan_interface.h>
// A very primitive mutex annotated with tsan annotations.
class Mutex {
public:
Mutex(bool prof, unsigned create_flags, unsigned destroy_flags=0)
: prof_(prof)
, locked_(false)
, seq_(0)
, destroy_flags_(destroy_flags) {
__tsan_mutex_create(this, create_flags);
}
~Mutex() {
__tsan_mutex_destroy(this, destroy_flags_);
}
void Lock() {
__tsan_mutex_pre_lock(this, 0);
LockImpl();
__tsan_mutex_post_lock(this, 0, 0);
}
bool TryLock() {
__tsan_mutex_pre_lock(this, __tsan_mutex_try_lock);
bool ok = TryLockImpl();
__tsan_mutex_post_lock(this, __tsan_mutex_try_lock |
(ok ? 0 : __tsan_mutex_try_lock_failed), 0);
return ok;
}
void Unlock() {
__tsan_mutex_pre_unlock(this, 0);
UnlockImpl();
__tsan_mutex_post_unlock(this, 0);
}
void Wait() {
for (int seq = seq_; seq == seq_;) {
Unlock();
usleep(100);
Lock();
}
}
void Broadcast() {
__tsan_mutex_pre_signal(this, 0);
LockImpl(false);
seq_++;
UnlockImpl();
__tsan_mutex_post_signal(this, 0);
}
private:
const bool prof_;
std::atomic<bool> locked_;
int seq_;
unsigned destroy_flags_;
// This models mutex profiling subsystem.
static Mutex prof_mu_;
static int prof_data_;
void LockImpl(bool prof = true) {
while (!TryLockImpl())
usleep(100);
if (prof && prof_)
Prof();
}
bool TryLockImpl() {
return !locked_.exchange(true);
}
void UnlockImpl() {
locked_.store(false);
}
void Prof() {
// This happens inside of mutex lock annotations.
__tsan_mutex_pre_divert(this, 0);
prof_mu_.Lock();
prof_data_++;
prof_mu_.Unlock();
__tsan_mutex_post_divert(this, 0);
}
};
Mutex Mutex::prof_mu_(false, __tsan_mutex_linker_init);
int Mutex::prof_data_;
|