<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Mutex on Chen Shungen</title><link>https://chenshungen.cn/tags/mutex/</link><description>Recent content in Mutex on Chen Shungen</description><generator>Hugo</generator><language>zh-cn</language><lastBuildDate>Mon, 20 Apr 2026 10:00:00 +0800</lastBuildDate><atom:link href="https://chenshungen.cn/tags/mutex/index.xml" rel="self" type="application/rss+xml"/><item><title>Go 并发原语 - Mutex</title><link>https://chenshungen.cn/blog/golang-concurrency/golang-mutex/</link><pubDate>Mon, 20 Apr 2026 10:00:00 +0800</pubDate><guid>https://chenshungen.cn/blog/golang-concurrency/golang-mutex/</guid><description>&lt;p>并发编程是 Go 的灵魂，而 &lt;strong>Mutex（互斥锁）&lt;/strong> 是并发控制的第一道防线。这篇文章带你从&amp;quot;为什么需要锁&amp;quot;开始，一路走到 Mutex 的演进原理、常见坑点和读写锁 RWMutex，争取一文把 Mutex 讲透。&lt;/p>
&lt;h2 id="一没有锁的世界有多危险">一、没有锁的世界有多危险？&lt;/h2>
&lt;p>先看一个经典的并发计数器问题：&lt;/p>
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 &lt;/button>&lt;div class="highlight">&lt;pre tabindex="0" class="chroma">&lt;code class="language-go" data-lang="go">&lt;span class="line">&lt;span class="cl">&lt;span class="kn">package&lt;/span> &lt;span class="nx">main&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">&lt;span class="kn">import&lt;/span> &lt;span class="p">(&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">	&lt;span class="s">&amp;#34;fmt&amp;#34;&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">	&lt;span class="s">&amp;#34;sync&amp;#34;&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">&lt;span class="p">)&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">&lt;span class="kd">func&lt;/span> &lt;span class="nf">main&lt;/span>&lt;span class="p">()&lt;/span> &lt;span class="p">{&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">	&lt;span class="kd">var&lt;/span> &lt;span class="nx">count&lt;/span> &lt;span class="kt">int&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">	&lt;span class="kd">var&lt;/span> &lt;span class="nx">wg&lt;/span> &lt;span class="nx">sync&lt;/span>&lt;span class="p">.&lt;/span>&lt;span class="nx">WaitGroup&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">	&lt;span class="k">for&lt;/span> &lt;span class="nx">i&lt;/span> &lt;span class="o">:=&lt;/span> &lt;span class="mi">0&lt;/span>&lt;span class="p">;&lt;/span> &lt;span class="nx">i&lt;/span> &lt;span class="p">&amp;lt;&lt;/span> &lt;span class="mi">10000&lt;/span>&lt;span class="p">;&lt;/span> &lt;span class="nx">i&lt;/span>&lt;span class="o">++&lt;/span> &lt;span class="p">{&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">		&lt;span class="nx">wg&lt;/span>&lt;span class="p">.&lt;/span>&lt;span class="nf">Add&lt;/span>&lt;span class="p">(&lt;/span>&lt;span class="mi">1&lt;/span>&lt;span class="p">)&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">		&lt;span class="k">go&lt;/span> &lt;span class="kd">func&lt;/span>&lt;span class="p">()&lt;/span> &lt;span class="p">{&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">			&lt;span class="k">defer&lt;/span> &lt;span class="nx">wg&lt;/span>&lt;span class="p">.&lt;/span>&lt;span class="nf">Done&lt;/span>&lt;span class="p">()&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">			&lt;span class="nx">count&lt;/span>&lt;span class="o">++&lt;/span> &lt;span class="c1">// 非原子操作：读取 → 加1 → 写回&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">		&lt;span class="p">}()&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">	&lt;span class="p">}&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">	&lt;span class="nx">wg&lt;/span>&lt;span class="p">.&lt;/span>&lt;span class="nf">Wait&lt;/span>&lt;span class="p">()&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">	&lt;span class="nx">fmt&lt;/span>&lt;span class="p">.&lt;/span>&lt;span class="nf">Println&lt;/span>&lt;span class="p">(&lt;/span>&lt;span class="s">&amp;#34;count:&amp;#34;&lt;/span>&lt;span class="p">,&lt;/span> &lt;span class="nx">count&lt;/span>&lt;span class="p">)&lt;/span> &lt;span class="c1">// 几乎不可能是 10000&lt;/span>
&lt;/span>&lt;/span>&lt;span class="line">&lt;span class="cl">&lt;span class="p">}&lt;/span>&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;/div>
&lt;p>多次运行，结果可能是 9831、9917、9756……每次都不一样。这就是典型的 &lt;strong>数据竞争（Data Race）&lt;/strong>。&lt;/p></description></item></channel></rss>