private volatile ConcurrentDictionary<TKey, TValue>.Tables m_tables;

 private class Tables
    {
      internal readonly ConcurrentDictionary<TKey, TValue>.Node[] m_buckets;
      internal readonly object[] m_locks;
      internal volatile int[] m_countPerLock;
      internal readonly IEqualityComparer<TKey> m_comparer;

      internal Tables(ConcurrentDictionary<TKey, TValue>.Node[] buckets, object[] locks, int[] countPerLock, IEqualityComparer<TKey> comparer)
      {
        this.m_buckets = buckets;
        this.m_locks = locks;
        this.m_countPerLock = countPerLock;
        this.m_comparer = comparer;
      }
    }

    private class Node
    {
      internal TKey m_key;
      internal TValue m_value;
      internal volatile ConcurrentDictionary<TKey, TValue>.Node m_next;
      internal int m_hashcode;

      internal Node(TKey key, TValue value, int hashcode, ConcurrentDictionary<TKey, TValue>.Node next)
      {
        this.m_key = key;
        this.m_value = value;
        this.m_next = next;
        this.m_hashcode = hashcode;
      }
    }

 private void GetBucketAndLockNo(int hashcode, out int bucketNo, out int lockNo, int bucketCount, int lockCount)
    {
      bucketNo = (hashcode & int.MaxValue) % bucketCount; //Node的位置
      lockNo = bucketNo % lockCount; // 锁位置
    }  

Volatile.Write<ConcurrentDictionary<TKey, TValue>.Node>(ref tables.m_buckets[bucketNo], new ConcurrentDictionary<TKey, TValue>.Node(key, value, hashCode, tables.m_buckets[bucketNo]));