[LITMUS^RT] The feature trace tool error

[Björn Brandenburg]

> On 04 Jul 2016, at 11:46, shijunjie92 <shijunjie92 at gmail.com> wrote:
> When I try to run the feature trace tool, I got the error 'could not open feathertrace device (/dev/litmus/sched_trace13): No such file or directory'. 
> Under the direction from 'http://stackoverflow.com/questions/22993077/litmus-rt-scheduling-traces', I am trying to disable the option 'Build a relocatable kernel'. But in my ubuntu system, this option is locked, which could not been disabled.
> '-*- Build a relocatable kernel'. 
> So, what should I do?

You have some other option enabled that force-selects the option 'Build a relocatable kernel’. You’ll first have to figure out which options unconditionally forces the option to be enabled, and then disable that option first. The Linux configuration system can be a bit complicated…

If you are starting from an Ubuntu configuration, you usually have tons of options enabled that you don’t need for your particular machine. I typically try to get something more tailored to my machine with ‘make localmodconfig’ and then ‘make localyesconfig’. This makes it slightly easier to track down problematic options.

- Björn