Concurrency-safe design of data structures in C++ concurrent programming?

In C++ concurrent programming, the concurrency-safe design of data structures is crucial: Critical section: Use a mutex lock to create a code block, allowing only one thread to execute at the same time. Read-write lock: allows multiple threads to read at the same time, but only one thread to write at the same time. Lock-free data structures: Use atomic operations to achieve concurrency safety without locks. Practical case: Thread-safe queue: Use critical sections to protect queue operations and achieve thread safety.

Concurrency safety design of data structures in C++ concurrent programming

In concurrent programming, it is crucial to ensure the thread safety of data structures . This prevents inconsistencies and data corruption when multiple threads access and modify data structures simultaneously. This article introduces concurrency-safe design techniques for various data structures in C++ concurrent programming and provides practical examples.

Critical Section
The critical section is a block of code that can only be executed by one thread at the same time. In C++, you can use a mutex lock (std::mutex) to create a critical section, as follows:

std::mutex m;
void func() {
  std::lock_guard<std::mutex> lock(m);
  // 受保护的临界区代码
}

Read-write lock
Read-write lock allows multiple threads Data structures are read simultaneously, but can only be written by one thread simultaneously. In C++11, read-write locks can be implemented through std::shared_timed_mutex:

std::shared_timed_mutex rw_lock;
void read_func() {
  std::shared_lock<std::shared_timed_mutex> lock(rw_lock);
  // 读操作
}

void write_func() {
  std::unique_lock<std::shared_timed_mutex> lock(rw_lock);
  // 写操作
}

Lock-free data structures
Lock-free data structures use specific techniques to operate without locks Achieve concurrency safety under the circumstances. A common approach is to use atomic operations, which perform reads and writes in a single indivisible operation. In C++, you can use std::atomic to create atomic variables:

std::atomic<int> counter;
void inc_counter() {
  ++counter;
}

Practical case: Thread-safe queue
The following is a thread-safe queue implementation Example:

class ConcurrentQueue {
private:
  std::mutex m;
  std::queue<int> q;

public:
  void push(int value) {
    std::lock_guard<std::mutex> lock(m);
    q.push(value);
  }

  int pop() {
    std::lock_guard<std::mutex> lock(m);
    if (q.empty()) { throw std::runtime_error("Queue is empty"); }
    int value = q.front();
    q.pop();
    return value;
  }
};

Thread safety of queues is achieved by using critical sections to protect queue operations.

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