#include #include #include "terra_memory_pool.h" template class LockFreeQueue { public: LockFreeQueue() : head_(new Node), tail_(head_.load()), memory_pool_(sizeof(Node) * 100) {} ~LockFreeQueue() { ...-Go服务器开发

这个队列的实现存在内存泄漏问题。在析构函数中，只释放了节点本身，而没有释放节点中存储的数据所分配的内存。另外，在push操作中，如果内存池无法分配新的节点，直接返回，但是没有进行任何处理。

以下是针对这些问题的一个优化版本：

#include #include #include “terra_memory_pool.h”

template class LockFreeQueue { public:

LockFreeQueue() : head_(new Node), tail_(head_.load()), memory_pool_(sizeof(Node) * 100) {}
~LockFreeQueue()
{
    while (Node *const old_head = head_)
    {
        Node *next_node = old_head->value_.second;
        delete old_head->value_.first;
        old_head->value_.first = nullptr;
        delete old_head;
        head_ = next_node;
    }
}

void push(const T &value)
{
    auto data = new T(value);
    Node *new_node = static_cast<Node *>(memory_pool_.Alloc(sizeof(Node)));
    if (new_node == nullptr)
    {
        delete data;
        return;
    }

    new (new_node) Node(std::make_pair(data, nullptr));
    Node *tail = tail_.load(std::memory_order_relaxed);
    tail->value_.second = new_node;
    tail_.store(new_node, std::memory_order_release);
    size_.fetch_add(1, std::memory_order_release);
}

bool try_pop(T &value)
{
    Node *const old_head = head_.load(std::memory_order_relaxed);
    Node *const new_head = old_head->value_.second;
    if (new_head == nullptr)
    {
        return false;
    }
    value = *(new_head->value_.first);
    head_.store(new_head, std::memory_order_release);
    size_.fetch_sub(1, std::memory_order_release);
    memory_pool_.Free(old_head, sizeof(Node));
    delete old_head->value_.first;
    old_head->value_.first = nullptr;
    return true;
}

bool empty() const
{
    return size_.load(std::memory_order_acquire) == 0;
}

private:

struct Node
{
    std::pair<T *, Node *> value_;
    Node() : value_(std::make_pair(nullptr, nullptr)) {}
    explicit Node(const std::pair<T *, Node *> &value) : value_(value) {}
};

std::atomic<Node *> head_;
std::atomic<Node *> tail_;
std::atomic<size_t> size_{0};
terra_memory_pool memory_pool_;

};

优化内容：