{"id":1182,"date":"2021-12-30T00:02:09","date_gmt":"2021-12-29T16:02:09","guid":{"rendered":"https:\/\/blog.cauchyschwarz.com\/?p=1182"},"modified":"2021-12-30T00:02:15","modified_gmt":"2021-12-29T16:02:15","slug":"%e5%86%85%e6%a0%b8tcp%e7%bb%93%e6%9d%9f%e6%b5%81%e7%a8%8b%e5%88%86%e6%9e%90","status":"publish","type":"post","link":"https:\/\/blog.cauchyschwarz.com\/?p=1182","title":{"rendered":"\u5185\u6838tcp\u7ed3\u675f\u6d41\u7a0b\u5206\u6790"},"content":{"rendered":"\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_82_2 ez-toc-wrap-right counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<label for=\"ez-toc-cssicon-toggle-item-69e0c4e1ee168\" class=\"ez-toc-cssicon-toggle-label\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-69e0c4e1ee168\" checked aria-label=\"Toggle\" \/><nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-1'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/blog.cauchyschwarz.com\/?p=1182\/#tcp_done\" >tcp_done<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/blog.cauchyschwarz.com\/?p=1182\/#inet_csk_destroy_sock\" >inet_csk_destroy_sock<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/blog.cauchyschwarz.com\/?p=1182\/#%E8%B0%83%E7%94%A8tcp_done%E7%9A%84%E6%97%B6%E6%9C%BA\" >\u8c03\u7528tcp_done\u7684\u65f6\u673a<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/blog.cauchyschwarz.com\/?p=1182\/#tcp_send_active_reset\" >tcp_send_active_reset<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/blog.cauchyschwarz.com\/?p=1182\/#%E9%87%8A%E6%94%BEcongestion_control%E7%9A%84%E6%97%B6%E6%9C%BA\" >\u91ca\u653econgestion control\u7684\u65f6\u673a<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h1 class=\"wp-block-heading\" id=\"%E7%BB%93%E6%9D%9F\"><span class=\"ez-toc-section\" id=\"tcp_done\"><\/span>tcp_done<span class=\"ez-toc-section-end\"><\/span><\/h1>\n\n\n\n<pre class=\"wp-block-code\"><code class=\"\">void tcp_done(struct sock *sk)\n{\n\tstruct request_sock *req = tcp_sk(sk)-&gt;fastopen_rsk;\n\n\tif (sk-&gt;sk_state == TCP_SYN_SENT || sk-&gt;sk_state == TCP_SYN_RECV)\n\t\tTCP_INC_STATS(sock_net(sk), TCP_MIB_ATTEMPTFAILS);\n\n\ttcp_set_state(sk, TCP_CLOSE);\n\ttcp_clear_xmit_timers(sk);\n\tif (req)\n\t\treqsk_fastopen_remove(sk, req, false);\n\n\tsk-&gt;sk_shutdown = SHUTDOWN_MASK;\n\n\tif (!sock_flag(sk, SOCK_DEAD))\n\t\tsk-&gt;sk_state_change(sk);\n\telse\n\t\tinet_csk_destroy_sock(sk);\n}\n<\/code><\/pre>\n\n\n\n<ol class=\"wp-block-list\"><li>\u8bbe\u7f6e\u72b6\u6001\u4e3aTCP_CLOSE\uff1b<\/li><li>\u6e05\u7406\u76f8\u5173timer\uff1apacing\uff0ccompressed ack\uff0c\u4ee5\u53ca\u5176\u4ed6delay\uff0c\u91cd\u4f20\u4e4b\u7c7b\u7684timer\uff1b<\/li><li>\u6e05\u7406fastopen\u76f8\u5173\u7684request_sock\uff1b 4.\u8bbe\u7f6e<code>sk_shutdown<\/code>\u4e3a<code>SHUTDOWN_MASK<\/code>\uff1b 5.\u5982\u679c\u8fd9\u4e2ask\u6ca1\u6709\u88ab\u6807\u8bb0<code>SOCK_DEAD<\/code>\uff0c\u90a3\u4e48\u8c03\u7528<code>sk_state_change<\/code>\u5904\u7406\u8fd9\u4e2ask\uff0c\u5426\u5219\u8c03\u7528<code>inet_csk_destroy_sock<\/code>\u5904\u7406\uff1b<code>sk_state_change<\/code>\u662f<code>sock<\/code>\u521d\u59cb\u5316\u7684\u65f6\u5019\u5728<code>sock_init_data<\/code>\u4e2d\u8bbe\u7f6e\u7684\uff0c\u9ed8\u8ba4\u503c\u4e3a<code>sock_def_wakeup<\/code>\u3002 \u8fd9\u4e2a<code>sk_state_change<\/code>\u662f<code>struct sock<\/code>\u8fd9\u4e2a\u57fa\u7c7b\u91cc\u521d\u59cb\u5316\u7684\u4e00\u4e2a\u51fd\u6570\uff0c\u5927\u81f4\u5c31\u662fepoll\u4e8b\u4ef6\u7684\u56de\u8c03\u7684\u610f\u601d\uff0c<code>sk_state_change<\/code>\u88ab\u8d4b\u503c\u4e3a<code>sock_def_wakeup<\/code>\u7528\u6765\u5524\u9192\u5e94\u7528\u8fdb\u7a0b\uff0c\u544a\u77e5\u5176\u6b64socket\u72b6\u6001\u5df2\u7ecf\u6539\u53d8\u3002<\/li><\/ol>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"inetcskdestroysock\"><span class=\"ez-toc-section\" id=\"inet_csk_destroy_sock\"><\/span>inet_csk_destroy_sock<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>\u90a3\u4e48\u7ee7\u7eed\u7406\u89e3<code>inet_csk_destroy_sock<\/code>\u7684\u903b\u8f91\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code class=\"\">void inet_csk_destroy_sock(struct sock *sk)\n{\n\tWARN_ON(sk-&gt;sk_state != TCP_CLOSE);\n\tWARN_ON(!sock_flag(sk, SOCK_DEAD));\n\n\t<em>\/* It cannot be in hash table! *\/<\/em>\n\tWARN_ON(!sk_unhashed(sk));\n\n\t<em>\/* If it has not 0 inet_sk(sk)-&gt;inet_num, it must be bound *\/<\/em>\n\tWARN_ON(inet_sk(sk)-&gt;inet_num &amp;&amp; !inet_csk(sk)-&gt;icsk_bind_hash);\n\n\tsk-&gt;sk_prot-&gt;destroy(sk);\n\n\tsk_stream_kill_queues(sk);\n\n\txfrm_sk_free_policy(sk);\n\n\tsk_refcnt_debug_release(sk);\n\n\tpercpu_counter_dec(sk-&gt;sk_prot-&gt;orphan_count);\n\n\tsock_put(sk);\n}\n<\/code><\/pre>\n\n\n\n<p>\u4ece\u8fd9\u4e2a\u5b9e\u73b0\u53ef\u4ee5\u770b\u51fa\uff0c\u5230<code>tcp_done<\/code>\u7684\u65f6\u5019\uff0c\u8fd9\u4e2aTCP socket\u5fc5\u987b\u65e9\u5df2\u7ecf\u4ecehash_info\u4e2d\u7ed9\u5220\u9664\u6389\u4e86\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"%E8%B0%83%E7%94%A8tcpdone%E7%9A%84%E6%97%B6%E6%9C%BA\"><span class=\"ez-toc-section\" id=\"%E8%B0%83%E7%94%A8tcp_done%E7%9A%84%E6%97%B6%E6%9C%BA\"><\/span>\u8c03\u7528tcp_done\u7684\u65f6\u673a<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<ol class=\"wp-block-list\"><li>\u5728<code>tcp_abort<\/code>\u4e2d\u8c03\u7528\uff0c\u800c<code>tcp_abort<\/code>\u662f\u7528\u6765\u8d4b\u503c\u7ed9sock_diag\u7684diag_destroy\u6307\u9488\u7684\uff1b<br>\u4f46\u662f\u8fd9\u4e2atcp_abort\u51fd\u6570\u5e94\u8be5\u662f\u6709bug\u7684\uff0c\u53ea\u80fd\u7528\u6765\u4f5c\u4e3a\u53c2\u8003\uff1b<\/li><li>\u5728<code>tcp_reset<\/code>\u4e2d\u8c03\u7528\uff1b<br>\u8fd9\u662f\u5728\u6536\u5230RSET\u5305\u540e\u8c03\u7528\u7684\uff1b<\/li><li>\u5728<code>tcp_rcv_state_process<\/code>\u4e2d\u8c03\u7528\uff1b<br>TCP\u5728\u6536\u5230\u5305\u540e\u4f1a\u8c03\u7528<code>tcp_rcv_state_process<\/code>\u8fdb\u884c\u5904\u7406\uff0c\u5177\u4f53\u903b\u8f91\u6682\u65f6\u4e0d\u7ba1\uff0c\u4ece\u4e2d\u53ef\u4ee5\u770b\u5230\u5904\u4e8e<strong>LAST_ACK<\/strong>\u7684socket\u5728\u6536\u5230\u6b63\u786e\u7684\u5305\u540e\u4f1a\u76f4\u63a5\u8c03\u7528tcp_done\u7ed3\u675f\u81ea\u5df1\uff1b<\/li><li>\u5728<code>tcp_v4_err<\/code>\u4e2d\u8c03\u7528\uff1b<\/li><li>\u5728<code>tcp_v4_syn_recv_sock<\/code>\u4e2d\u8c03\u7528\uff1b<\/li><li>\u5728<code>tcp_time_wait<\/code>\u4e2d\u8c03\u7528\uff1b<br>\u5728TCP socket\u8981\u8fdb\u5165time-wait\u6216\u8005fin-wait-2\u72b6\u6001\u65f6\uff0c\u4f1a\u8c03\u7528<code>tcp_time_wait<\/code>\u51fd\u6570\uff0c\u521b\u5efa\u4e00\u4e2a\u65b0\u7684inet_timewait_sock\u6765\u53d6\u4ee3\u539f\u6765\u7684sock\uff0c\u5e76\u4e14\u5c06\u539f\u6765\u7684sock\u91ca\u653e\u6389\u4ee5\u8282\u7ea6\u5185\u5b58\uff1b<\/li><li>\u5728<code>tcp_write_err<\/code>\u4e2d\u8c03\u7528\uff1b<\/li><li>\u5728<code>tcp_out_of_resources<\/code>\u4e2d\u8c03\u7528\uff1b<\/li><li>\u5728<code>tcp_keepalive_timer<\/code>\u4e2d\u8c03\u7528\uff1b<\/li><li>\u5728<code>tcp_v6_err<\/code>\u4e2d\u8c03\u7528\uff1b<\/li><li>\u5728<code>tcp_v6_syn_recv_sock<\/code>\u4e2d\u8c03\u7528\uff1b<\/li><\/ol>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"tcpsendactivereset\"><span class=\"ez-toc-section\" id=\"tcp_send_active_reset\"><\/span>tcp_send_active_reset<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"%E9%87%8A%E6%94%BEcongestion-control%E7%9A%84%E6%97%B6%E6%9C%BA\"><span class=\"ez-toc-section\" id=\"%E9%87%8A%E6%94%BEcongestion_control%E7%9A%84%E6%97%B6%E6%9C%BA\"><\/span>\u91ca\u653econgestion control\u7684\u65f6\u673a<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>\u5728tcp_cleanup_congestion_control\u4e2d\u4f1a\u8c03\u7528congestion control\u6ce8\u518c\u7684destroy\u51fd\u6570\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li><code>tcp_reinit_congestion_control<\/code>\u5207\u6362cc\u7b97\u6cd5\u65f6\u8c03\u7528\uff1b<\/li><li><code>tcp_v4_destroy_sock<\/code>\u8c03\u7528\uff1b<br>\u90a3\u4e48\u4ec0\u4e48\u65f6\u5019\u4f1a\u8c03\u7528\u8fd9\u4e2a<code>tcp_v4_destroy_sock<\/code>\u5462\uff1f<\/li><\/ul>\n\n\n\n<ol class=\"wp-block-list\"><li><code>tcp_v6_destroy_sock<\/code>\u91cc\u4f1a\u8c03\u7528\uff0c\u6709\u70b9\u7c7b\u4f3ctcp_ipv6\u662ftcp_ipv4\u7684\u5b50\u7c7b\u7684\u610f\u601d\uff1b<\/li><li><code>tcp_v4_destroy_sock<\/code>\u6ce8\u518c\u6210\u4e86tcp_ipv4\u7684<code>destroy<\/code>\u51fd\u6570\uff1b<\/li><\/ol>\n\n\n\n<p>\u90a3\u4e48\u4ec0\u4e48\u65f6\u5019\u4f1a\u8c03\u7528\u8fd9\u4e2a\u6ce8\u518c\u7684destroy\u51fd\u6570\u5462\uff1f<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li><code>inet_csk_destroy_sock<\/code>\u51fd\u6570\u8c03\u7528\uff1b<br>\u55ef\uff0c\u53ef\u4ee5\u628atcp_sock\u770b\u4f5cinet_connection_sock\u7684\u5b50\u7c7b\u5427\u3002<br><code>tcp_done<\/code>\u91cc\u53ef\u80fd\u4f1a\u8c03\u7528<code>inet_csk_destroy_sock<\/code>\uff0c\u4e5f\u5c31\u662f\u8bf4<code>tcp_done<\/code>\u51fd\u6570\u91cc\u5927\u6982\u7387\u5c31\u628atcp socket\u5173\u8054\u7684congestion control\u7ed9\u91ca\u653e\u6389\u4e86\u3002<\/li><li><code>sk_common_release<\/code>\u4e2d\u8c03\u7528\uff1b<\/li><\/ol>\n","protected":false},"excerpt":{"rendered":"<p>tcp_done \u8bbe\u7f6e\u72b6\u6001\u4e3aTCP_CLOSE\uff1b \u6e05\u7406\u76f8\u5173timer\uff1apacing\uff0ccompressed ack\uff0c\u4ee5\u53ca\u5176\u4ed6delay\uff0c\u91cd\u4f20\u4e4b\u7c7b\u7684timer\uff1b \u6e05\u7406fastopen\u76f8\u5173\u7684request_&#46;&#46;&#46;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[37,100],"class_list":["post-1182","post","type-post","status-publish","format-standard","hentry","category-10","tag-kernel","tag-tcp"],"_links":{"self":[{"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=\/wp\/v2\/posts\/1182","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1182"}],"version-history":[{"count":1,"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=\/wp\/v2\/posts\/1182\/revisions"}],"predecessor-version":[{"id":1183,"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=\/wp\/v2\/posts\/1182\/revisions\/1183"}],"wp:attachment":[{"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1182"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1182"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1182"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}