C# 开发一个旋转锁

以下是我自己在看书的时候开发了旋转锁,可是我对旋转锁本身却不怎么了解,欢迎大家一起探讨。

 public partial class SpinLock
    {
       private int state;
       private EventWaitHandle available = new AutoResetEvent(false);
       private static bool isSingleProc = (Environment.ProcessorCount == 1);
       private const int outerTryCount = 5;
       private const int cexTryCount = 100;
       public void Enter(out bool taken)
       {
           taken = false;
           while (!taken)
           {
               if (isSingleProc)
               {
                   Thread.BeginCriticalRegion();
                   taken = Interlocked.CompareExchange(ref state, 1, 0) == 0;
                   if (!taken)
                       Thread.EndCriticalRegion();
               }
               else
               {
                   for (int i = 0; !taken && i < outerTryCount; i++)
                   {
                       Thread.BeginCriticalRegion();
                       int tries = 0;
                       taken=Interlocked.CompareExchange(ref state,1,0)==0;
                       while (!taken && tries++ < cexTryCount)
                       {
                           Thread.SpinWait(1);
                       }
                       if (!taken)
                       {
                           Thread.EndCriticalRegion();
                           Thread.Sleep(0);
                       }
                   }
               }
               if (!taken) available.WaitOne();
           }
           return;
       }
       public void Enter()
       {
           bool b;
            Enter(out b);
       }
       public void Exit()
       {
         bool taken=Interlocked.CompareExchange(ref state,0,1)==1;
         if (!taken)
         {
             available.Set();
             Thread.EndCriticalRegion();
         }
       }
    }

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