title: Running Android systrace on device
body: <p>I'm unable to run the Android SDK tool called systrace.pl because I get errors like:</p>
  
  <pre><code>error opening /sys/kernel/debug/tracing/options/overwrite: No such file or directory 
  </code></pre>
  
  <p>And indeed the /sys/kernel/debug/tracing directory doesn't even exist.</p>
  
  <p>A little research showed I need to enable debugfs with the following command:</p>
  
  <pre><code>mount -o rw,remount -t debugfs none /sys/kernel/debug
  </code></pre>
  
  <p>Running mount there afterwards indicates the debugfs is running:</p>
  
  <pre><code>#mount
  ...
  /sys/kernel/debug /sys/kernel/debug debugfs rw,relatime 0 0
  ...
  </code></pre>
  
  <p>And I have trace enabled (all items) in the developer settings menu. I'm using the stock ROM 4.1.1 on a Samsung Galaxy S3.</p>
  
  <p>There's a lot of articles out there on systrace for Android but nothing seems to solve the problem of no files actually being generated in /sys/kernel/debug/tracing...</p>