{"id":207787,"date":"2025-07-08T15:27:47","date_gmt":"2025-07-08T07:27:47","guid":{"rendered":"https:\/\/server.hk\/cnblog\/207787\/"},"modified":"2025-07-08T15:27:47","modified_gmt":"2025-07-08T07:27:47","slug":"%e5%90%8c%e6%ad%a5%e5%8e%9f%e8%af%ad%e5%8e%9f%e5%ad%90%e5%8c%85","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/207787\/","title":{"rendered":"\u540c\u6b65\u539f\u8bed\u539f\u5b50\u5305"},"content":{"rendered":"<p><b><\/b> <\/p>\n<p>\u5f53\u524d\u4f4d\u7f6e\uff1a <span>&gt;<\/span> <span>&gt;<\/span> <span>&gt;<\/span> <span>&gt;<\/span> <span>\u540c\u6b65\u539f\u8bed\u539f\u5b50\u5305<\/span><\/p>\n<p><span>\u6765\u6e90\uff1astackoverflow<\/span><br \/>\n<span>2024-04-25 17:03:31<\/span><br \/>\n<span><i><\/i>0\u6d4f\u89c8<\/span><br \/>\n<span style=\"cursor: pointer\"><i><\/i>\u6536\u85cf<\/span> <\/p>\n<p>\u5c0f\u4f19\u4f34\u4eec\u5bf9Golang\u7f16\u7a0b\u611f\u5174\u8da3\u5417\uff1f\u662f\u5426\u6b63\u5728\u5b66\u4e60\u76f8\u5173\u77e5\u8bc6\u70b9\uff1f\u5982\u679c\u662f\uff0c\u90a3\u4e48\u672c\u6587\u300a\u540c\u6b65\u539f\u8bed\u539f\u5b50\u5305\u300b\uff0c\u5c31\u5f88\u9002\u5408\u4f60\uff0c\u672c\u7bc7\u6587\u7ae0\u8bb2\u89e3\u7684\u77e5\u8bc6\u70b9\u4e3b\u8981\u5305\u62ec\u3002\u5728\u4e4b\u540e\u7684\u6587\u7ae0\u4e2d\u4e5f\u4f1a\u591a\u591a\u5206\u4eab\u76f8\u5173\u77e5\u8bc6\u70b9\uff0c\u5e0c\u671b\u5bf9\u5927\u5bb6\u7684\u77e5\u8bc6\u79ef\u7d2f\u6709\u6240\u5e2e\u52a9\uff01<\/p>\n<p> \u95ee\u9898\u5185\u5bb9<br \/>\n <\/p>\n<p>go \u4e2d\u7684\u540c\u6b65\u5305\u6709 once \u539f\u8bed\u3002 do()\u65b9\u6cd5\u5b9e\u73b0\u4e86<\/p>\n<pre>func (o *once) do(f func()) {\n    if atomic.loaduint32(&amp;o.done) == 1 {\n        return\n    }\n    \/\/ slow-path.\n    o.m.lock()\n    defer o.m.unlock()\n    if o.done == 0 {\n        defer atomic.storeuint32(&amp;o.done, 1)\n        f()\n    }\n}<\/pre>\n<p>\u4e3a\u4ec0\u4e48\u6211\u4e0d\u80fd\u4f7f\u7528\u6b64\u65b9\u6cd5\u7684\u5176\u4ed6\u7248\u672c\uff1f<\/p>\n<pre>func (o *Once) Do(f func()) {\n    if o.done == 1 {\n        return\n    }\n    \/\/ Slow-path.\n    o.m.Lock()\n    defer o.m.Unlock()\n    if o.done == 0 {\n        defer atomic.StoreUint32(&amp;o.done, 1)\n        f()\n    }\n}<\/pre>\n<p> <\/p>\n<h2>\u89e3\u51b3\u65b9\u6848<\/h2>\n<p> <\/p>\n<p> \u4e0d\u4fdd\u8bc1\u60a8\u5bf9 <code>if o.done == 1<\/code> \u4e2d <code>done<\/code> \u7684\u8bfb\u53d6\u5c06\u81ea\u52a8\u8fdb\u884c\u3002\u5728\u8fd9\u4e9b\u60c5\u51b5\u4e0b\uff0c\u60a8\u7684\u7a0b\u5e8f\u7684\u884c\u4e3a\u662f\u672a\u5b9a\u4e49\u7684\u3002\u6709\u5f88\u591a\u65b9\u6cd5\u53ef\u80fd\u4f1a\u51fa\u9519\u2014\u2014\u4f8b\u5982\uff0c\u60a8\u53ef\u80fd\u4f1a\u8bfb\u53d6\u53e6\u4e00\u4e2a goroutine \u4e2d\u5199\u51fa\u7684\u90e8\u5206\u503c\u3002<\/p>\n<p>\u597d\u4e86\uff0c\u672c\u6587\u5230\u6b64\u7ed3\u675f\uff0c\u5e26\u5927\u5bb6\u4e86\u89e3\u4e86\u300a\u540c\u6b65\u539f\u8bed\u539f\u5b50\u5305\u300b\uff0c\u5e0c\u671b\u672c\u6587\u5bf9\u4f60\u6709\u6240\u5e2e\u52a9\uff01\u5173\u6ce8\u516c\u4f17\u53f7\uff0c\u7ed9\u5927\u5bb6\u5206\u4eab\u66f4\u591aGolang\u77e5\u8bc6\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5f53\u524d\u4f4d\u7f6e\uff1a &gt; &gt; &#46;&#46;&#46;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-207787","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207787","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=207787"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207787\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=207787"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=207787"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=207787"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}