2.1 Simple Spin Lock Explanation. (20pts) Here is a piece of a code, please use your own words to explain what does this code do, and what does the function 'void increment () ' do? Hinclude ciostream> Hinclude class SpinLock 1 public: void lock() \{ while (flag.test_and_set(std::memory_order_acquire)) \{ // spin ) void unlock() \{ flag.clear(std:memory_order_release); ) private: std::atomic_flag flag = ATOMIC_FLAG_INIT; 3. Spintock spinlock; int counter =0; void increment() \{ for ( int i=0;i