C++ 线程安全的queue：报错

你既然用到了锁，那么你解锁的过程呢？我只看到了加锁啊！目前，看不出来其他的地方还有什么问题######void put(const T& x)

{

｛

ScopeMutexLock lock(m_mutex);

LOG_DEBUG("Queue, put data\n");

m_queue.push_back(x);

LOG_DEBUG("Queue, aftet push_back,size :%ld\n", m_queue.size());

}

m_notEmpty.notify();

}

T get()

{

ScopeMutexLock lock(m_mutex);

while (m_queue.empty())

{

printf("Queue,in wait\n");

m_notEmpty.wait();

}

LOG_DEBUG("Queue,after wait, will get data\n");

//assert(!m_Queue.empty());

T front(m_queue.front());

m_queue.pop_front();

return front;

}

notify之前就需要把m_mutex unlock，因为wait函数内部会先unlock再block锁，所以你notify之前不释放锁的话，就会死锁。

Reference: http://www.cnblogs.com/ngnetboy/p/3521547.html

######看不出代码有问题， 把你导致死锁的测试代码贴出来看看。######为什么不在进程里面读队列，之后分配给线程去处理，只要管理好线程的反馈就可以了。######void put(const T& x)

{

ScopeMutexLock lock(m_mutex);

LOG_DEBUG("Queue, put data\n");

bool need_notify = m_queue.empty();

m_queue.push_back(x);

LOG_DEBUG("Queue, aftet push_back,size :%ld\n", m_queue.size());

if(need_notify){

m_notEmpty.notify();

}

}

T get()

{

ScopeMutexLock lock(m_mutex);

while(m_queue.empty())

{

printf("Queue,in wait\n");

添加 unlock(m_mutex);

m_notEmpty.wait();

重新加锁 lock(m_mutex);

}

LOG_DEBUG("Queue,after wait, will get data\n");

//assert(!m_Queue.empty());

T front(m_queue.front());

m_queue.pop_front();

return front;

}

###### 谢谢各位解答：改为这样已经好，但是如果还用之前的ScopeMutexLock lock(m_mutex) 把notify 放在调用完put的地方调用一遍还是不行
        void put(const T& x)         {                 //printf("queue will lock b put:%p\n",m_mutex.getMutex());                 //ScopeMutexLock lock(m_mutex);                 m_lock->lock();                 printf("Queue, before put data!!!!\n");                 m_queue.push_back(x);                 printf("Queue, aftet put data!!!,size :%ld\n", m_queue.size());                 m_lock->unlock();                 m_notEmpty.notify();         }

        T get()         {                 //printf("queue will lock b get!!!!:%p\n",m_mutex.getMutex());                 //ScopeMutexLock lock(m_mutex);                 m_lock->lock();                 printf("Queue,before get!!!,size:%ld\n",m_queue.size());                 while (m_queue.empty())                 {                         printf("Queue,in wait!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!\n");                         m_notEmpty.wait();                 }                 printf("Queue,after wait!!!!, will get data,queue size:%ld\n",m_queue.size());                 m_lock->unlock();                 //assert(!m_Queue.empty());                 T front(m_queue.front());                 m_queue.pop_front();                 return front;         } ###### 看这个，经典实现
https://github.com/chenshuo/muduo/blob/master/muduo/base/BlockingQueue.h
C++ 2011 ######这个不行的，我之前设计的跟他的一样。。。######