pthread_mutex_lock __pthread_mutex_lock_full:断言失败,强健且0x4000000

Question

我正在开发一个服务器端项目,该项目应该接受100多个客户端连接.

它是使用boost :: thread的多线程程序.我boost::lock_guard<boost::mutex>用来锁定共享成员数据的一些地方.还有一个BlockingQueue<ConnectionPtr>包含输入连接.执行BlockingQueue:

template <typename DataType>
class BlockingQueue : private boost::noncopyable
{
public:
    BlockingQueue()
        : nblocked(0), stopped(false)
    {

    }

    ~BlockingQueue()
    {
        Stop(true);
    }

    void Push(const DataType& item)
    {
        boost::mutex::scoped_lock lock(mutex);
        queue.push(item);
        lock.unlock();
        cond.notify_one(); // cond.notify_all();
    }

    bool Empty() const
    {
        boost::mutex::scoped_lock lock(mutex);
        return queue.empty();
    }

    std::size_t Count() const
    {
        boost::mutex::scoped_lock lock(mutex);
        return queue.size();
    }

    bool TryPop(DataType& poppedItem)
    {
        boost::mutex::scoped_lock lock(mutex);
        if (queue.empty())
            return false;

        poppedItem = queue.front();
        queue.pop();

        return true;
    }

    DataType WaitPop()
    {
        boost::mutex::scoped_lock lock(mutex);

        ++nblocked;
        while (!stopped && queue.empty()) // Or: if (queue.empty())
            cond.wait(lock);
        --nblocked;

        if (stopped)
        {
            cond.notify_all(); // Tell Stop() that this thread has left
            BOOST_THROW_EXCEPTION(BlockingQueueTerminatedException());
        }

        DataType tmp(queue.front());
        queue.pop();

        return tmp;
    }

    void Stop(bool wait)
    {
        boost::mutex::scoped_lock lock(mutex);
        stopped = true;
        cond.notify_all();

        if (wait) // Wait till all blocked threads on the waiting queue to leave BlockingQueue::WaitPop()
        {
            while (nblocked)
                cond.wait(lock);
        }
    }

private:
    std::queue<DataType>          queue;
    mutable boost::mutex          mutex;
    boost::condition_variable_any cond;
    unsigned int                  nblocked;
    bool                          stopped;
};

对于每个Connection,都有一个ConcurrentQueue<StreamPtr>包含输入Streams的.执行ConcurrentQueue:

template <typename DataType>
class ConcurrentQueue : private boost::noncopyable
{
public:
    void Push(const DataType& item)
    {
        boost::mutex::scoped_lock lock(mutex);
        queue.push(item);
    }

    bool Empty() const
    {
        boost::mutex::scoped_lock lock(mutex);
        return queue.empty();
    }

    bool TryPop(DataType& poppedItem)
    {
        boost::mutex::scoped_lock lock(mutex);
        if (queue.empty())
            return false;

        poppedItem = queue.front();
        queue.pop();

        return true;
    }
private:
    std::queue<DataType> queue;
    mutable boost::mutex mutex;
};

调试程序时,没关系.但是在使用50或100个或更多客户端连接进行负载测试时,有时会中止

pthread_mutex_lock.c:321: __pthread_mutex_lock_full: Assertion `robust || (oldval & 0x40000000) == 0' failed.

我不知道发生了什么,每次都无法复制.

我google了很多,但没有运气.请指教.

谢谢.

彼得

Answer 1

0x40000000是FUTEX_OWNER_DIED- futex.h标题中包含以下文档:

/*
 * The kernel signals via this bit that a thread holding a futex
 * has exited without unlocking the futex. The kernel also does
 * a FUTEX_WAKE on such futexes, after setting the bit, to wake
 * up any possible waiters:
 */
#define FUTEX_OWNER_DIED        0x40000000

因此断言似乎表明持有锁的线程由于某种原因而退出 - 是否有一种方法可以在线程对象持有锁时被销毁？

要检查的另一件事是你是否在某处有某种内存损坏.Valgrind可能是一个可以帮助你的工具.