SpinWait.Reset 方法

定義

命名空間:

System.Threading

組件:

System.Threading.dll

來源:

SpinWait.cs

重設微調計數器。

public:
 void Reset();

public void Reset ();

member this.Reset : unit -> unit

Public Sub Reset ()

範例

以下是在簡單無鎖定堆疊實作中使用 SpinWait 的範例。 (這只是範例。如果需要有效率且安全線程的堆疊，請考慮使用 ConcurrentStack.)

using System;
using System.Threading;

public class LockFreeStack<T>
{
    private volatile Node m_head;
    private class Node { public Node Next; public T Value; }
    public void Push(T item)
    {
        var spin = new SpinWait();
        Node node = new Node { Value = item }, head;
        while (true)
        {
            head = m_head;
            node.Next = head;
            if (Interlocked.CompareExchange(ref m_head, node, head) == head) break;
            spin.SpinOnce();
        }
    }
    public bool TryPop(out T result)
    {
        result = default(T);
        var spin = new SpinWait();
        Node head;
        while (true)
        {
            head = m_head;
            if (head == null) return false;
            if (Interlocked.CompareExchange(ref m_head, head.Next, head) == head)
            {
                result = head.Value;
                return true;
            }
            spin.SpinOnce();
        }
    }
}

Imports System.Threading

Public Class LockFreeStack(Of T)
    Private m_head As Node
    Private Class Node
        Public [Next] As Node
        Public Value As T
    End Class
    Public Sub Push(ByVal item As T)
        Dim spin As New SpinWait()
        Dim head As Node, node As New Node With {.Value = item}
        While True
            Thread.MemoryBarrier()
            head = m_head
            node.Next = head
            If Interlocked.CompareExchange(m_head, node, head) Is head Then Exit While
            spin.SpinOnce()
        End While
    End Sub
    Public Function TryPop(ByRef result As T) As Boolean
        result = CType(Nothing, T)
        Dim spin As New SpinWait()
        Dim head As Node
        While True
            Thread.MemoryBarrier()
            head = m_head
            If head Is Nothing Then Return False
            If Interlocked.CompareExchange(m_head, head.Next, head) Is head Then
                result = head.Value
                Return True
            End If
            spin.SpinOnce()
        End While
    End Function
End Class

備註

這會發出 SpinOnce 和 NextSpinWillYield 行為，就像沒有在此實例上發出對 的呼叫 SpinOnce 一樣。 SpinWait如果實例重複使用多次，重設實例可能會很有用，以避免太快產生。

另請參閱

• SpinWait
• 如何：使用 SpinWait 實作兩階段等候作業