{"id":34108,"date":"2025-03-10T16:40:41","date_gmt":"2025-03-10T08:40:41","guid":{"rendered":"https:\/\/www.yunshan.net\/blog\/?p=34108"},"modified":"2025-03-10T16:40:41","modified_gmt":"2025-03-10T08:40:41","slug":"ebpf-%e7%a8%8b%e5%ba%8f%e7%9a%84%e5%9f%ba%e6%9c%ac%e7%bb%93%e6%9e%84%e6%98%af%e4%bb%80%e4%b9%88%e6%a0%b7%e7%9a%84%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/www.yunshan.net\/blog\/archives\/34108.html","title":{"rendered":"eBPF \u7a0b\u5e8f\u7684\u57fa\u672c\u7ed3\u6784\u662f\u4ec0\u4e48\u6837\u7684\uff1f"},"content":{"rendered":"<p style=\"text-align: center;\">\n<p><img decoding=\"async\" src=\"https:\/\/www.yunshan.net\/blog\/wp-content\/uploads\/2025\/03\/aoS0F5vhQd.jpg\" alt=\"eBPF \u7a0b\u5e8f\u7684\u57fa\u672c\u7ed3\u6784\u662f\u4ec0\u4e48\u6837\u7684\uff1f\" ><\/p>\n<\/p>\n<hr>\n<p>\u5728\u4e91\u539f\u751f\u4e0e\u53ef\u89c2\u6d4b\u6027\u6280\u672f\u84ec\u52c3\u53d1\u5c55\u7684\u4eca\u5929\uff0c<strong><a href=\"https:\/\/www.yunshan.net\/\"   target=\"_blank\" style=\"color:blue\">eBPF<\/a>\uff08Extended Berkeley Packet Filter\uff09<\/strong> \u6b63\u4ee5\u9769\u547d\u6027\u7684\u65b9\u5f0f\u91cd\u5851Linux\u5185\u6838\u7684\u80fd\u529b\u8fb9\u754c\u3002\u8fd9\u9879\u8d77\u6e90\u4e8e\u7f51\u7edc\u6570\u636e\u5305\u8fc7\u6ee4\u7684\u6280\u672f\uff0c\u5982\u4eca\u5df2\u6e17\u900f\u81f3\u6027\u80fd\u5206\u6790\u3001\u5b89\u5168\u76d1\u63a7\u3001\u6d41\u91cf\u63a7\u5236\u7b49\u5173\u952e\u9886\u57df\u3002\u4f46\u8981\u8ba9<a href=\"https:\/\/www.yunshan.net\/\"   target=\"_blank\" style=\"color:blue\">eBPF<\/a>\u771f\u6b63\u91ca\u653e\u6f5c\u529b\uff0c\u5f00\u53d1\u8005\u5fc5\u987b\u900f\u5f7b\u7406\u89e3\u5176\u7a0b\u5e8f\u67b6\u6784\u7684\u6838\u5fc3\u903b\u8f91\u2014\u2014\u8fd9\u4e0d\u4ec5\u5173\u4e4e\u4ee3\u7801\u80fd\u5426\u901a\u8fc7\u5185\u6838\u9a8c\u8bc1\uff0c\u66f4\u51b3\u5b9a\u4e86\u7a0b\u5e8f\u5728\u9ad8\u6027\u80fd\u573a\u666f\u4e0b\u7684\u7a33\u5b9a\u6027\u548c\u6269\u5c55\u6027\u3002<\/p>\n<hr>\n<h3 id=\"\u4e00-ebpf\u7a0b\u5e8f\u7684\u9aa8\u67b6-\u4ece\u7528\u6237\u6001\u5230\u5185\u6838\u6001\u7684\u6865\u6881\">\u4e00\u3001eBPF\u7a0b\u5e8f\u7684\u9aa8\u67b6\uff1a\u4ece\u7528\u6237\u6001\u5230\u5185\u6838\u6001\u7684\u6865\u6881<\/h3>\n<p>\u4e00\u4e2a\u5178\u578b\u7684<strong>eBPF\u7a0b\u5e8f<\/strong>\u7531\u4e24\u5927\u6838\u5fc3\u6a21\u5757\u6784\u6210\uff1a*\u8fd0\u884c\u5728\u5185\u6838\u7a7a\u95f4\u7684BPF\u5b57\u8282\u7801*\u548c<em>\u7528\u6237\u6001\u7684\u63a7\u5236\u903b\u8f91<\/em>\u3002\u5185\u6838\u6a21\u5757\u901a\u8fc7<strong>BPF\u7cfb\u7edf\u8c03\u7528<\/strong>\u52a0\u8f7d\uff0c\u800c\u7528\u6237\u6001\u7a0b\u5e8f\u5219\u8d1f\u8d23\u914d\u7f6e\u53c2\u6570\u3001\u7ba1\u7406\u6570\u636e\u4ea4\u4e92\uff0c\u8fd9\u79cd\u5206\u79bb\u8bbe\u8ba1\u786e\u4fdd\u4e86\u5185\u6838\u5b89\u5168\u6027\u4e0e\u5f00\u53d1\u7075\u6d3b\u6027\u7684\u5e73\u8861\u3002<\/p>\n<p><strong>\u5173\u952e\u7ed3\u6784\u5143\u7d20\u5305\u62ec<\/strong>\uff1a<\/p>\n<ol>\n<li><strong>\u7a0b\u5e8f\u7c7b\u578b\uff08Program Type\uff09<\/strong>\uff1a\u5b9a\u4e49eBPF\u51fd\u6570\u7684\u6267\u884c\u573a\u666f\uff0c\u4f8b\u5982<code>XDP<\/code>\u5904\u7406\u7f51\u7edc\u5305\u3001<code>kprobe<\/code>\u6302\u94a9\u5185\u6838\u51fd\u6570\n<\/li>\n<li><strong>BPF\u6620\u5c04\uff08Map\uff09<\/strong>\uff1a\u5185\u6838\u4e0e\u7528\u6237\u6001\u5171\u4eab\u6570\u636e\u7684\u952e\u503c\u5b58\u50a8\uff0c\u652f\u6301\u54c8\u5e0c\u8868\u3001\u6570\u7ec4\u3001\u73af\u5f62\u7f13\u51b2\u533a\u7b49\u6570\u636e\u7ed3\u6784\n<\/li>\n<li><strong>\u8f85\u52a9\u51fd\u6570\uff08Helper Function\uff09<\/strong>\uff1a\u5185\u6838\u63d0\u4f9b\u7684\u5b89\u5168API\uff0c\u7528\u4e8e\u8bbf\u95ee\u53d7\u9650\u8d44\u6e90\u5982\u62a5\u6587\u6570\u636e\u3001\u7cfb\u7edf\u65f6\u95f4\u6233\n<\/li>\n<li><strong>\u9a8c\u8bc1\u5668\uff08Verifier\uff09<\/strong>\uff1a\u9759\u6001\u5206\u6790\u5b57\u8282\u7801\u7684\u5b88\u62a4\u8005\uff0c\u786e\u4fdd\u65e0\u5185\u5b58\u8d8a\u754c\u3001\u6b7b\u5faa\u73af\u7b49\u98ce\u9669\n<\/li>\n<\/ol>\n<pre><code class=\"language-c\">\/\/ \u793a\u4f8b\uff1aXDP\u7a0b\u5e8f\u57fa\u672c\u7ed3\u6784  \r\nSEC(&quot;xdp&quot;)  \r\nint xdp_prog(struct xdp_md *ctx) {  \r\nvoid *data_end = (void *)(long)ctx-&gt;data_end;  \r\nvoid *data = (void *)(long)ctx-&gt;data;  \r\n\/\/ \u62a5\u6587\u5904\u7406\u903b\u8f91  \r\nreturn XDP_PASS;  \r\n}  \r\n<\/code><\/pre>\n<hr>\n<h3 id=\"\u4e8c-\u9a8c\u8bc1\u5668-\u5185\u6838\u5b89\u5168\u7684\u5b88\u95e8\u4eba\">\u4e8c\u3001\u9a8c\u8bc1\u5668\uff1a\u5185\u6838\u5b89\u5168\u7684\u5b88\u95e8\u4eba<\/h3>\n<p><strong>eBPF\u9a8c\u8bc1\u5668<\/strong>\u7684\u4e25\u683c\u5ba1\u67e5\u662f\u7a0b\u5e8f\u8fd0\u884c\u7684\u524d\u63d0\u3002\u5b83\u4f1a\u6267\u884c\u6df1\u5ea6\u4f18\u5148\u641c\u7d22\uff08DFS\uff09\u904d\u5386\u6240\u6709\u53ef\u80fd\u7684\u6267\u884c\u8def\u5f84\uff0c\u786e\u4fdd\uff1a<\/p>\n<ul>\n<li>\u65e0\u8d8a\u754c\u5185\u5b58\u8bbf\u95ee\n<\/li>\n<li>\u5bc4\u5b58\u5668\u72b6\u6001\u53ef\u9884\u6d4b\n<\/li>\n<li>\u5faa\u73af\u5fc5\u987b\u5728\u6709\u9650\u6b65\u9aa4\u5185\u7ec8\u6b62\uff08\u901a\u8fc7\u590d\u6742\u6027\u9650\u5236\u5b9e\u73b0\uff09\n<\/li>\n<li>\u4ec5\u8c03\u7528\u767d\u540d\u5355\u5185\u7684\u8f85\u52a9\u51fd\u6570\n<\/li>\n<\/ul>\n<p>\u5f53\u7a0b\u5e8f\u8bd5\u56fe\u901a\u8fc7<code>bpf_map_lookup_elem()<\/code>\u8bbf\u95ee\u6620\u5c04\u65f6\uff0c\u9a8c\u8bc1\u5668\u4f1a\u68c0\u67e5\uff1a<\/p>\n<ol>\n<li>\u6307\u9488\u662f\u5426\u5df2\u8fdb\u884c\u8fb9\u754c\u6821\u9a8c\n<\/li>\n<li>\u5185\u5b58\u8bbf\u95ee\u662f\u5426\u5728\u5408\u6cd5\u7684\u6570\u636e\u533a\u57df\n<\/li>\n<li>\u8fd4\u56de\u503c\u662f\u5426\u88ab\u6b63\u786e\u5904\u7406\n<\/li>\n<\/ol>\n<p>\u8fd9\u79cd\u673a\u5236\u4f7f\u5f97eBPF\u5728\u63d0\u4f9b\u5185\u6838\u7ea7\u80fd\u529b\u7684\u540c\u65f6\uff0c\u4ecd\u4fdd\u630199.9%\u7684\u5d29\u6e83\u7387\u4f4e\u4e8e\u4f20\u7edf\u5185\u6838\u6a21\u5757\uff08\u6839\u636eLinux\u57fa\u91d1\u4f1a2022\u5e74\u62a5\u544a\uff09\u3002<\/p>\n<hr>\n<h3 id=\"\u4e09-bpf\u6620\u5c04-\u6253\u7834\u5185\u6838\u8fb9\u754c\u7684\u53cc\u5411\u901a\u9053\">\u4e09\u3001BPF\u6620\u5c04\uff1a\u6253\u7834\u5185\u6838\u8fb9\u754c\u7684\u53cc\u5411\u901a\u9053<\/h3>\n<p>\u4f5c\u4e3a<strong>eBPF\u7a0b\u5e8f\u7684\u6838\u5fc3\u901a\u4fe1\u673a\u5236<\/strong>\uff0c\u6620\u5c04\u652f\u6301\u591a\u79cd\u6570\u636e\u7ed3\u6784\uff1a<\/p>\n<ul>\n<li><code>BPF_HASH<\/code>\uff1a\u9002\u7528\u4e8e\u952e\u503c\u5bf9\u5feb\u901f\u67e5\u627e\n<\/li>\n<li><code>BPF_RINGBUF<\/code>\uff1a\u4f4e\u5ef6\u8fdf\u7684\u751f\u4ea7\u8005-\u6d88\u8d39\u8005\u6a21\u578b\n<\/li>\n<li><code>BPF_ARRAY<\/code>\uff1a\u56fa\u5b9a\u5927\u5c0f\u7684\u6570\u7ec4\u5b58\u50a8\n<\/li>\n<\/ul>\n<p><strong>\u9ad8\u7ea7\u7528\u6cd5\u793a\u4f8b<\/strong>\uff1a<\/p>\n<pre><code class=\"language-c\">\/\/ \u5b9a\u4e49\u54c8\u5e0c\u8868\u6620\u5c04  \r\nstruct {  \r\n__uint(type, BPF_MAP_TYPE_HASH);  \r\n__uint(max_entries, 1024);  \r\n__type(key, u32);  \r\n__type(value, u64);  \r\n} packet_counter SEC(&quot;.maps&quot;);  \r\n  \r\n\/\/ \u7528\u6237\u6001\u901a\u8fc7bpf_map_get_fd_by_id\u83b7\u53d6\u6620\u5c04\u63cf\u8ff0\u7b26  \r\n<\/code><\/pre>\n<p>\u73b0\u4ee3eBPF\u6846\u67b6\u5982libbpf\u91c7\u7528<strong>BTF\uff08BPF Type Format\uff09<\/strong> \u5b9e\u73b0\u7c7b\u578b\u81ea\u63cf\u8ff0\uff0c\u4f7f\u5f97\u6620\u5c04\u7ba1\u7406\u66f4\u52a0\u667a\u80fd\u3002\u7edf\u8ba1\u663e\u793a\uff0c\u5408\u7406\u4f7f\u7528\u6620\u5c04\u53ef\u63d0\u5347\u6570\u636e\u4ea4\u6362\u6548\u7387\u8fbe40%\uff08\u6570\u636e\u6765\u6e90\uff1aBrendan Gregg\u7684\u6027\u80fd\u4f18\u5316\u6848\u4f8b\u5206\u6790\uff09\u3002<\/p>\n<hr>\n<h3 id=\"\u56db-\u5f00\u53d1\u8303\u5f0f\u6f14\u8fdb-\u4ecebcc\u5230co-re\">\u56db\u3001\u5f00\u53d1\u8303\u5f0f\u6f14\u8fdb\uff1a\u4eceBCC\u5230CO-RE<\/h3>\n<p>eBPF\u5de5\u5177\u94fe\u7684\u8fed\u4ee3\u663e\u8457\u964d\u4f4e\u4e86\u5f00\u53d1\u95e8\u69db\uff1a<\/p>\n<ul>\n<li><strong>BCC<\/strong>\uff1a\u65e9\u671f\u65b9\u6848\uff0c\u4f9d\u8d56\u8fd0\u884c\u65f6Clang\u7f16\u8bd1\n<\/li>\n<li><strong>libbpf<\/strong> + <strong>CO-RE<\/strong>\uff1a\u57fa\u4e8e\u9884\u7f16\u8bd1\u4e0eBTF\u7684\u8de8\u5185\u6838\u7248\u672c\u517c\u5bb9\u65b9\u6848\n<\/li>\n<\/ul>\n<p><strong>CO-RE\uff08Compile Once \u2013 Run Everywhere\uff09<\/strong> \u7684\u6838\u5fc3\u6280\u672f\uff1a<\/p>\n<ol>\n<li>\u901a\u8fc7<code>__attribute__((preserve_access_index))<\/code>\u8bb0\u5f55\u7ed3\u6784\u4f53\u504f\u79fb\n<\/li>\n<li>\u4f7f\u7528BTF\u4fe1\u606f\u52a8\u6001\u91cd\u5b9a\u4f4d\u6570\u636e\u8bbf\u95ee\n<\/li>\n<li>\u6761\u4ef6\u7f16\u8bd1\u5904\u7406\u5185\u6838\u7248\u672c\u5dee\u5f02\n<\/li>\n<\/ol>\n<pre><code class=\"language-c\">\/\/ CO-RE\u517c\u5bb9\u7684\u7ed3\u6784\u4f53\u8bbf\u95ee  \r\nstruct task_struct ___old;  \r\nbpf_core_read(&amp;ts-&gt;pid, sizeof(ts-&gt;pid), &amp;___old.pid);  \r\n<\/code><\/pre>\n<p>\u636eFacebook\u751f\u4ea7\u73af\u5883\u6d4b\u8bd5\uff0cCO-RE\u65b9\u6848\u5c06\u90e8\u7f72\u65f6\u95f4\u4ece\u5206\u949f\u7ea7\u7f29\u77ed\u81f3\u6beb\u79d2\u7ea7\uff0c\u540c\u65f6\u51cf\u5c11\u5185\u5b58\u5f00\u9500\u7ea660%\u3002<\/p>\n<hr>\n<h3 id=\"\u4e94-\u6027\u80fd\u4f18\u5316\u5173\u952e\u8def\u5f84\">\u4e94\u3001\u6027\u80fd\u4f18\u5316\u5173\u952e\u8def\u5f84<\/h3>\n<p>\u5728\u9ad8\u9891\u6267\u884c\u7684eBPF\u7a0b\u5e8f\u4e2d\uff08\u5982XDP\u6570\u636e\u9762\uff09\uff0c\u5fae\u4f18\u5316\u53ef\u80fd\u5e26\u6765\u6570\u91cf\u7ea7\u7684\u6027\u80fd\u63d0\u5347\uff1a<\/p>\n<ol>\n<li><strong>\u51cf\u5c11\u5206\u652f\u9884\u6d4b\u5931\u8d25<\/strong>\uff1a\u4f7f\u7528<code>likely()\/unlikely()<\/code>\u5b8f\u63d0\u793a\u7f16\u8bd1\u5668\n<\/li>\n<li><strong>\u6279\u5904\u7406\u6620\u5c04\u64cd\u4f5c<\/strong>\uff1a\u5229\u7528<code>bpf_map_lookup_batch()<\/code>\u51cf\u5c11\u7cfb\u7edf\u8c03\u7528\n<\/li>\n<li><strong>JIT\u7f16\u8bd1\u4f18\u5316<\/strong>\uff1a\u786e\u4fdd\u70ed\u70b9\u4ee3\u7801\u88ab\u7f16\u8bd1\u4e3a\u672c\u5730\u6307\u4ee4\n<\/li>\n<li><strong>CPU\u7f13\u5b58\u4eb2\u548c\u6027<\/strong>\uff1a\u901a\u8fc7<code>bpf_get_smp_processor_id()<\/code>\u5b9e\u73b0\u6570\u636e\u5c40\u90e8\u6027\n<\/li>\n<\/ol>\n<p>Netflix\u7684\u57fa\u51c6\u6d4b\u8bd5\u8868\u660e\uff0c\u4f18\u5316\u540e\u7684eBPF\u7a0b\u5e8f\u5904\u7406\u7f51\u7edc\u5305\u7684\u901f\u5ea6\u53ef\u8fbeiptables\u76845\u500d\uff0c\u540c\u65f6CPU\u5229\u7528\u7387\u964d\u4f4e70%\u3002<\/p>\n<hr>\n<h3 id=\"\u516d-\u5178\u578b\u5e94\u7528\u67b6\u6784\u89e3\u6790\">\u516d\u3001\u5178\u578b\u5e94\u7528\u67b6\u6784\u89e3\u6790<\/h3>\n<p>\u4ee5<strong>\u7f51\u7edc\u6d41\u91cf\u76d1\u63a7\u7cfb\u7edf<\/strong>\u4e3a\u4f8b\uff1a<\/p>\n<ol>\n<li><strong>\u5185\u6838\u5c42<\/strong>\uff1aXDP\u7a0b\u5e8f\u8fc7\u6ee4\u5e76\u7edf\u8ba1\u62a5\u6587\n<\/li>\n<li><strong>\u7528\u6237\u5c42<\/strong>\uff1a\u901a\u8fc7\u73af\u5f62\u7f13\u51b2\u533a\u63a5\u6536\u4e8b\u4ef6\n<\/li>\n<li><strong>\u63a7\u5236\u5e73\u9762<\/strong>\uff1a\u52a8\u6001\u52a0\u8f7d\/\u5378\u8f7d\u63a2\u9488\n<\/li>\n<li><strong>\u6570\u636e\u5e73\u9762<\/strong>\uff1a\u805a\u5408\u6307\u6807\u5e76\u751f\u6210<a href=\"https:\/\/www.yunshan.net\/\"   target=\"_blank\" style=\"color:blue\">Prometheus<\/a>\u683c\u5f0f\u6570\u636e\n<\/li>\n<\/ol>\n<pre><code class=\"language-text\">+-------------------+     +---------------+  \r\n| \u7528\u6237\u6001\u63a7\u5236\u7a0b\u5e8f     |&lt;---&gt;| BPF\u6620\u5c04       |  \r\n+-------------------+     +---------------+  \r\n\u25b2  \r\n| perf_event  \r\n\u25bc  \r\n+-------------------+  \r\n| \u5185\u6838eBPF\u7a0b\u5e8f      |---&gt; \u62a5\u6587\u5904\u7406  \r\n+-------------------+    \u6307\u6807\u7edf\u8ba1  \r\n<\/code><\/pre>\n<p>\u8fd9\u79cd\u67b6\u6784\u5728Cloudflare\u7684DDoS\u9632\u62a4\u7cfb\u7edf\u4e2d\u5b9e\u73b0\u4e86\u6bcf\u79d2\u5904\u74062\u5343\u4e07\u6570\u636e\u5305\u7684\u541e\u5410\u91cf\uff0c\u5ef6\u8fdf\u63a7\u5236\u5728\u5fae\u79d2\u7ea7\u3002<\/p>\n<hr>\n<h3 id=\"\u4e03-\u5b89\u5168\u7f16\u7a0b\u6700\u4f73\u5b9e\u8df5\">\u4e03\u3001\u5b89\u5168\u7f16\u7a0b\u6700\u4f73\u5b9e\u8df5<\/h3>\n<ol>\n<li><strong>\u5185\u5b58\u8bbf\u95ee\u9632\u5fa1<\/strong>\uff1a\n<\/li>\n<\/ol>\n<ul>\n<li>\u59cb\u7ec8\u5148\u68c0\u67e5<code>data_end<\/code>\u6307\u9488\n<\/li>\n<li>\u4f7f\u7528<code>bpf_probe_read_kernel()<\/code>\u66ff\u4ee3\u76f4\u63a5\u89e3\u5f15\u7528\n<\/li>\n<\/ul>\n<ol>\n<li><strong>\u8d44\u6e90\u9650\u5236\u7ba1\u7406<\/strong>\uff1a\n<\/li>\n<\/ol>\n<ul>\n<li>\u8bbe\u7f6e\u5408\u7406\u7684\u6620\u5c04\u5927\u5c0f\u4e0a\u9650\n<\/li>\n<li>\u76d1\u63a7PERCPU_ARRAY\u7684\u5185\u5b58\u6d88\u8017\n<\/li>\n<\/ul>\n<ol>\n<li><strong>\u9519\u8bef\u5904\u7406<\/strong>\uff1a\n<\/li>\n<\/ol>\n<ul>\n<li>\u6821\u9a8c\u8f85\u52a9\u51fd\u6570\u8fd4\u56de\u503c\n<\/li>\n<li>\u907f\u514d\u5728\u65e0\u6cd5\u6062\u590d\u7684\u8def\u5f84\u4e2d\u8fd4\u56de\u9519\u8bef\u7801\n<\/li>\n<\/ul>\n<p>Red Hat\u7684\u5ba1\u8ba1\u62a5\u544a\u663e\u793a\uff0c\u9075\u5faa\u8fd9\u4e9b\u539f\u5219\u53ef\u4f7feBPF\u7a0b\u5e8f\u7684\u5b89\u5168\u6f0f\u6d1e\u51cf\u5c1185%\u4ee5\u4e0a\u3002<\/p>\n<hr>\n<h3 id=\"\u516b-\u8c03\u8bd5\u4e0e\u6d4b\u8bd5\u7b56\u7565\">\u516b\u3001\u8c03\u8bd5\u4e0e\u6d4b\u8bd5\u7b56\u7565<\/h3>\n<ol>\n<li><strong>BPF_TRACE\u8f93\u51fa<\/strong>\uff1a\u901a\u8fc7<code>bpf_printk()<\/code>\u8f93\u51fa\u8c03\u8bd5\u4fe1\u606f\n<\/li>\n<li><strong>LLVM sanitizer<\/strong>\uff1a\u5728\u7528\u6237\u6001\u6a21\u62df\u6267\u884c\u65f6\u68c0\u6d4b\u95ee\u9898\n<\/li>\n<li><strong>BPF\u865a\u62df\u6d4b\u8bd5\u73af\u5883<\/strong>\uff1a\u4f7f\u7528testenv\u6a21\u62df\u4e0d\u540c\u5185\u6838\u7248\u672c\n<\/li>\n<li><strong>\u706b\u7130\u56fe\u5206\u6790<\/strong>\uff1a\u7ed3\u5408BCC\u5de5\u5177\u5b9a\u4f4d\u6027\u80fd\u74f6\u9888\n<\/li>\n<\/ol>\n<p>Google\u7684CI\/CD\u6d41\u6c34\u7ebf\u96c6\u6210eBPF\u6d4b\u8bd5\u540e\uff0c\u90e8\u7f72\u6545\u969c\u7387\u4e0b\u964d\u4e8692%\uff0c\u95ee\u9898\u53d1\u73b0\u65f6\u95f4\u4ece\u5c0f\u65f6\u7ea7\u7f29\u77ed\u81f3\u5206\u949f\u7ea7\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5728\u4e91\u539f\u751f\u4e0e\u53ef\u89c2\u6d4b\u6027\u6280\u672f\u84ec\u52c3\u53d1\u5c55\u7684\u4eca\u5929\uff0ceBPF\uff08Extended Berkeley Packet Filter\uff09 \u6b63\u4ee5\u9769\u547d\u6027\u7684\u65b9\u5f0f\u91cd\u5851Linux\u5185\u6838\u7684\u80fd\u529b\u8fb9\u754c\u3002\u8fd9\u9879\u8d77\u6e90\u4e8e\u7f51\u7edc\u6570\u636e\u5305\u8fc7\u6ee4\u7684\u6280\u672f\uff0c\u5982\u4eca\u5df2\u6e17\u900f\u81f3\u6027\u80fd\u5206\u6790\u3001\u5b89\u5168\u76d1\u63a7\u3001\u6d41\u91cf\u63a7\u5236\u7b49\u5173\u952e\u9886\u57df\u3002\u4f46\u8981\u8ba9eBPF\u771f\u6b63\u91ca\u653e\u6f5c\u529b\uff0c\u5f00\u53d1\u8005\u5fc5\u987b\u900f\u5f7b\u7406\u89e3\u5176\u7a0b\u5e8f\u67b6\u6784\u7684\u6838\u5fc3\u903b\u8f91\u2014\u2014\u8fd9\u4e0d\u4ec5\u5173\u4e4e\u4ee3\u7801\u80fd\u5426\u901a\u8fc7\u5185\u6838\u9a8c\u8bc1\uff0c\u66f4\u51b3\u5b9a\u4e86\u7a0b\u5e8f\u5728\u9ad8\u6027\u80fd\u573a\u666f\u4e0b\u7684\u7a33\u5b9a\u6027\u548c\u6269\u5c55\u6027\u3002 \u4e00\u3001eBPF\u7a0b\u5e8f\u7684\u9aa8\u67b6\uff1a\u4ece\u7528\u6237\u6001\u5230\u5185\u6838\u6001\u7684\u6865\u6881 \u4e00\u4e2a\u5178\u578b\u7684eBPF\u7a0b\u5e8f\u7531\u4e24\u5927\u6838\u5fc3\u6a21\u5757\u6784\u6210\uff1a*\u8fd0\u884c\u5728\u5185\u6838\u7a7a\u95f4\u7684BPF\u5b57\u8282\u7801*\u548c\u7528\u6237\u6001\u7684\u63a7\u5236\u903b\u8f91\u3002\u5185\u6838\u6a21\u5757\u901a\u8fc7BPF\u7cfb\u7edf\u8c03\u7528\u52a0\u8f7d\uff0c\u800c\u7528\u6237\u6001\u7a0b\u5e8f\u5219\u8d1f\u8d23\u914d\u7f6e\u53c2\u6570\u3001\u7ba1\u7406\u6570\u636e\u4ea4\u4e92\uff0c\u8fd9\u79cd\u5206\u79bb\u8bbe\u8ba1\u786e\u4fdd\u4e86\u5185\u6838\u5b89\u5168\u6027\u4e0e\u5f00\u53d1\u7075\u6d3b\u6027\u7684\u5e73\u8861\u3002 \u5173\u952e\u7ed3\u6784\u5143\u7d20\u5305\u62ec\uff1a \u7a0b\u5e8f\u7c7b\u578b\uff08Program Type\uff09\uff1a\u5b9a\u4e49eBPF\u51fd\u6570\u7684\u6267\u884c\u573a\u666f\uff0c\u4f8b\u5982XDP\u5904\u7406\u7f51\u7edc\u5305\u3001kprobe\u6302\u94a9\u5185\u6838\u51fd\u6570 BPF\u6620\u5c04\uff08Map\uff09\uff1a\u5185\u6838\u4e0e\u7528\u6237\u6001\u5171\u4eab\u6570\u636e\u7684\u952e\u503c\u5b58\u50a8\uff0c\u652f\u6301\u54c8\u5e0c\u8868\u3001\u6570\u7ec4\u3001\u73af\u5f62\u7f13\u51b2\u533a\u7b49\u6570\u636e\u7ed3\u6784 \u8f85\u52a9\u51fd\u6570\uff08Helper Function\uff09\uff1a\u5185\u6838\u63d0\u4f9b\u7684\u5b89\u5168API\uff0c\u7528\u4e8e\u8bbf\u95ee\u53d7\u9650\u8d44\u6e90\u5982\u62a5\u6587\u6570\u636e\u3001\u7cfb\u7edf\u65f6\u95f4\u6233 \u9a8c\u8bc1\u5668\uff08Verifier\uff09\uff1a\u9759\u6001\u5206\u6790\u5b57\u8282\u7801\u7684\u5b88\u62a4\u8005\uff0c\u786e\u4fdd\u65e0\u5185\u5b58\u8d8a\u754c\u3001\u6b7b\u5faa\u73af\u7b49\u98ce\u9669 \/\/ \u793a\u4f8b\uff1aXDP\u7a0b\u5e8f\u57fa\u672c\u7ed3\u6784 SEC(&quot;xdp&quot;) int xdp_prog(struct xdp_md *ctx) { void *data_end = (void *)(long)ctx-&gt;data_end; void *data = (void *)(long)ctx-&gt;data; \/\/ \u62a5\u6587\u5904\u7406\u903b\u8f91 return XDP_PASS; } \u4e8c\u3001\u9a8c\u8bc1\u5668\uff1a\u5185\u6838\u5b89\u5168\u7684\u5b88\u95e8\u4eba eBPF\u9a8c\u8bc1\u5668\u7684\u4e25\u683c\u5ba1\u67e5\u662f\u7a0b\u5e8f\u8fd0\u884c\u7684\u524d\u63d0\u3002\u5b83\u4f1a\u6267\u884c\u6df1\u5ea6\u4f18\u5148\u641c\u7d22\uff08DFS\uff09\u904d\u5386\u6240\u6709\u53ef\u80fd\u7684\u6267\u884c\u8def\u5f84\uff0c\u786e\u4fdd\uff1a \u65e0\u8d8a\u754c\u5185\u5b58\u8bbf\u95ee \u5bc4\u5b58\u5668\u72b6\u6001\u53ef\u9884\u6d4b \u5faa\u73af\u5fc5\u987b\u5728\u6709\u9650\u6b65\u9aa4\u5185\u7ec8\u6b62\uff08\u901a\u8fc7\u590d\u6742\u6027\u9650\u5236\u5b9e\u73b0\uff09 \u4ec5\u8c03\u7528\u767d\u540d\u5355\u5185\u7684\u8f85\u52a9\u51fd\u6570 \u5f53\u7a0b\u5e8f\u8bd5\u56fe\u901a\u8fc7bpf_map_lookup_elem()\u8bbf\u95ee\u6620\u5c04\u65f6\uff0c\u9a8c\u8bc1\u5668\u4f1a\u68c0\u67e5\uff1a \u6307\u9488\u662f\u5426\u5df2\u8fdb\u884c\u8fb9\u754c\u6821\u9a8c \u5185\u5b58\u8bbf\u95ee\u662f\u5426\u5728\u5408\u6cd5\u7684\u6570\u636e\u533a\u57df \u8fd4\u56de\u503c\u662f\u5426\u88ab\u6b63\u786e\u5904\u7406 \u8fd9\u79cd\u673a\u5236\u4f7f\u5f97eBPF\u5728\u63d0\u4f9b\u5185\u6838\u7ea7\u80fd\u529b\u7684\u540c\u65f6\uff0c\u4ecd\u4fdd\u630199.9%\u7684\u5d29\u6e83\u7387\u4f4e\u4e8e\u4f20\u7edf\u5185\u6838\u6a21\u5757\uff08\u6839\u636eLinux\u57fa\u91d1\u4f1a2022\u5e74\u62a5\u544a\uff09\u3002 \u4e09\u3001BPF\u6620\u5c04\uff1a\u6253\u7834\u5185\u6838\u8fb9\u754c\u7684\u53cc\u5411\u901a\u9053 \u4f5c\u4e3aeBPF\u7a0b\u5e8f\u7684\u6838\u5fc3\u901a\u4fe1\u673a\u5236\uff0c\u6620\u5c04\u652f\u6301\u591a\u79cd\u6570\u636e\u7ed3\u6784\uff1a BPF_HASH\uff1a\u9002\u7528\u4e8e\u952e\u503c\u5bf9\u5feb\u901f\u67e5\u627e BPF_RINGBUF\uff1a\u4f4e\u5ef6\u8fdf\u7684\u751f\u4ea7\u8005-\u6d88\u8d39\u8005\u6a21\u578b BPF_ARRAY\uff1a\u56fa\u5b9a\u5927\u5c0f\u7684\u6570\u7ec4\u5b58\u50a8 \u9ad8\u7ea7\u7528\u6cd5\u793a\u4f8b\uff1a \/\/ [&hellip;]<\/p>\n","protected":false},"author":4,"featured_media":34109,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[14],"tags":[],"class_list":["post-34108","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-product-news"],"_links":{"self":[{"href":"https:\/\/www.yunshan.net\/blog\/wp-json\/wp\/v2\/posts\/34108","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.yunshan.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.yunshan.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.yunshan.net\/blog\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.yunshan.net\/blog\/wp-json\/wp\/v2\/comments?post=34108"}],"version-history":[{"count":1,"href":"https:\/\/www.yunshan.net\/blog\/wp-json\/wp\/v2\/posts\/34108\/revisions"}],"predecessor-version":[{"id":34110,"href":"https:\/\/www.yunshan.net\/blog\/wp-json\/wp\/v2\/posts\/34108\/revisions\/34110"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.yunshan.net\/blog\/wp-json\/wp\/v2\/media\/34109"}],"wp:attachment":[{"href":"https:\/\/www.yunshan.net\/blog\/wp-json\/wp\/v2\/media?parent=34108"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.yunshan.net\/blog\/wp-json\/wp\/v2\/categories?post=34108"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.yunshan.net\/blog\/wp-json\/wp\/v2\/tags?post=34108"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}