c++ - 在Boost中实现自旋锁。需要的例子

我想知道boost是否具有任何有助于实现自旋锁的库。我知道boost支持互斥锁，但是我找不到在boost中显示或描述自旋锁的任何示例，任何显示如何使用boost(最好)实现自旋锁的示例都将受到赞赏。(C++ 98)

最佳答案

使用 Boost.Atomic 的示例:

#include <boost/atomic.hpp>

class SpinLock
{
    boost::atomic_flag flag; // it differs from std::atomic_flag a bit -
                             // does not require ATOMIC_FLAG_INIT
public:
    void lock()
    {
        while( flag.test_and_set(boost::memory_order_acquire) )
            ;
    }
    bool try_lock()
    {
        return !flag.test_and_set(boost::memory_order_acquire);
    }
    void unlock()
    {
        flag.clear(boost::memory_order_release);
    }
};

LIVE Demo on Coliru

#include <boost/range/algorithm.hpp>
#include <boost/atomic.hpp>
#include <boost/thread.hpp>
#include <iostream>
#include <vector>

class SpinLock
{
    boost::atomic_flag flag;
public:
    void lock()
    {
        while( flag.test_and_set(boost::memory_order_acquire) )
            ;
    }
    bool try_lock()
    {
        return !flag.test_and_set(boost::memory_order_acquire);
    }
    void unlock()
    {
        flag.clear(boost::memory_order_release);
    }
};

int main()
{
    using namespace std; using namespace boost;

    SpinLock lock;
    vector<thread> v;
    for(auto i = 0; i!=4; ++i)
        v.emplace_back([&lock, i]
        {
            for(auto j = 0; j!=16; ++j)
            {
                this_thread::yield();
                lock_guard<SpinLock> x(lock);
                cout << "Hello from " << i << flush << "\tj = " << j << endl;
            }
        });
    for(auto &t: v)
        t.join();
}

输出为:

Hello from 0    j = 0
Hello from 1    j = 0
Hello from 3    j = 0
Hello from 2    j = 0
Hello from 3    j = 1
Hello from 1    j = 1
Hello from 3    j = 2
Hello from 2    j = 1
Hello from 1    j = 2
Hello from 2    j = 2
Hello from 1    j = 3
Hello from 2    j = 3
Hello from 1    j = 4
Hello from 3    j = 3
Hello from 2    j = 4
Hello from 1    j = 5
Hello from 2    j = 5
Hello from 1    j = 6
Hello from 2    j = 6
Hello from 1    j = 7
Hello from 2    j = 7
Hello from 1    j = 8
Hello from 2    j = 8
Hello from 3    j = 4
Hello from 2    j = 9
Hello from 3    j = 5
Hello from 1    j = 9
Hello from 2    j = 10
Hello from 1    j = 10
Hello from 2    j = 11
Hello from 3    j = 6
Hello from 1    j = 11
Hello from 2    j = 12
Hello from 3    j = 7
Hello from 1    j = 12
Hello from 2    j = 13
Hello from 3    j = 8
Hello from 2    j = 14
Hello from 3    j = 9
Hello from 1    j = 13
Hello from 2    j = 15
Hello from 1    j = 14
Hello from 3    j = 10
Hello from 1    j = 15
Hello from 3    j = 11
Hello from 3    j = 12
Hello from 3    j = 13
Hello from 3    j = 14
Hello from 3    j = 15
Hello from 0    j = 1
Hello from 0    j = 2
Hello from 0    j = 3
Hello from 0    j = 4
Hello from 0    j = 5
Hello from 0    j = 6
Hello from 0    j = 7
Hello from 0    j = 8
Hello from 0    j = 9
Hello from 0    j = 10
Hello from 0    j = 11
Hello from 0    j = 12
Hello from 0    j = 13
Hello from 0    j = 14
Hello from 0    j = 15

关于c++ - 在Boost中实现自旋锁。需要的例子，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/19742993/