以下是C++代码示例，用于测量互斥锁和自旋锁之间的唤醒延迟时间。

#include #include #include #include

constexpr int LOOP_COUNT = 10000;

std::mutex mtx; std::atomic flag = false;

void mutexWorker() { for(int i = 0; i < LOOP_COUNT; ++i) { std::unique_lockstd::mutex lock(mtx); flag = true; lock.unlock(); } }

void spinLockWorker() { for(int i = 0; i < LOOP_COUNT; ++i) { while(flag.exchange(false, std::memory_order_acquire) == false) {} } }

int main() { auto mutexStart = std::chrono::high_resolution_clock::now(); std::thread t1(mutexWorker); std::thread t2(mutexWorker); t1.join(); t2.join(); auto mutexEnd = std::chrono::high_resolution_clock::now();

auto spinLockStart = std::chrono::high_resolution_clock::now();
std::thread t3(spinLockWorker);
std::thread t4(spinLockWorker);
t3.join();
t4.join();
auto spinLockEnd = std::chrono::high_resolution_clock::now();

std::cout << "Mutex time: " << std::chrono::duration_cast(mutexEnd - mutexStart).count() / (2 * LOOP_COUNT) << " nanoseconds" << std::endl;
std::cout << "Spin lock time: " << std::chrono::duration_cast(spinLockEnd - spinLockStart).count() / (2 * LOOP_COUNT) << " nanoseconds" << std::endl;

return 0;

}

该代码使用了两个线程（t1和t2）来测试互斥锁的唤醒延迟时间，并使用了两个线程（t3和t4）测试自旋锁的唤醒