printk
<p><img src="https://www.showdoc.cc/server/api/attachment/visitfile/sign/4c7acfeea9b96886c1a5163f96123e9a?showdoc=.jpg" alt="" /></p>
<h3>change log level</h3>
<p>查看当前printk打印消息的log等级</p>
<pre><code># cat /proc/sys/kernel/printk
# 7 4 1 7</code></pre>
<p>“7 4 1 7” 分别对应console_loglevel、default_message_loglevel、minimum_c onsole_loglevel、default_console_loglevel，意味着只有优先级高于KERN_DEBUG(7)的打印消息才能输出到终端</p>
<p>改变console_loglevel
<code># echo 8 4 1 7 > /proc/sys/kernel/printk</code></p>