tracy/server/tracy_benaphore.h
2017-11-15 21:44:55 +01:00

56 lines
1.2 KiB
C++

//---------------------------------------------------------
// For conditions of distribution and use, see
// https://github.com/preshing/cpp11-on-multicore/blob/master/LICENSE
//---------------------------------------------------------
#ifndef __TRACY_CPP11OM_BENAPHORE_H__
#define __TRACY_CPP11OM_BENAPHORE_H__
#include <cassert>
#include <thread>
#include <atomic>
#include "tracy_sema.h"
namespace tracy
{
class NonRecursiveBenaphore
{
private:
std::atomic<int> m_contentionCount;
DefaultSemaphoreType m_sema;
public:
NonRecursiveBenaphore() : m_contentionCount(0) {}
void lock()
{
if (m_contentionCount.fetch_add(1, std::memory_order_acquire) > 0)
{
m_sema.wait();
}
}
bool tryLock()
{
if (m_contentionCount.load(std::memory_order_relaxed) != 0)
return false;
int expected = 0;
return m_contentionCount.compare_exchange_strong(expected, 1, std::memory_order_acquire);
}
void unlock()
{
int oldCount = m_contentionCount.fetch_sub(1, std::memory_order_release);
assert(oldCount > 0);
if (oldCount > 1)
{
m_sema.signal();
}
}
};
}
#endif // __CPP11OM_BENAPHORE_H__