Home / ubuntu / Questions / 465148
Accepted
Jeyaram
Asked: 2014-05-13 22:54:45 +0800 CST

ftrace on ubuntu 12.04

  • 772

I wish to work with ftrace on ubuntu and able to use trace-cmd (http://manpages.ubuntu.com/manpages/precise/en/man1/trace-cmd-start.1.html).

But as per this http://lwn.net/Articles/365835/, I want to manually access /sys/kernel/debug/tracing section.

 $ cd /sys/kernel/debug/
-bash: cd: /sys/kernel/debug/: Permission denied

debugfs in mounted.

 $ mount |grep debugfs
15:nodev on /sys/kernel/debug type debugfs (rw)

Please share your knowledge.

12.04

1 Answers

  1. Best Answer

    Accessing the debugfs requires root privileges. To open a root shell, open a normal shell and run

    $ sudo -i

    You will be asked for your password, then be given a root shell. In that shell, you can cd to /sys/kernel/debug.

    • 2