RTEMS User Level Tracing?

[Chris Johns]

On 19/12/2015 6:36 AM, isaac.gutekunst wrote:
> 
> We're interested in trace some application data in our RTEMS project.
> Here's a bunch of background and thoughts:
> 
> I've read the following pages:
>     * https://devel.rtems.org/wiki/Developer/Tracing
>     * https://devel.rtems.org/wiki/Developer/Tracing/Trace_Linker
> 
> I think I have an understanding of the current system as documented.
> Tracing user defined data types seems to be missing. I'm looking for
> something more like barectf. Is there any such support available, or any
> plans to support it? I don't want to reinvent the wheel.

User defined data is not directly support but can be added if you add a
custom generator. There is not a great deal of documentation about how
to do this. An example generator is:

 https://git.rtems.org/rtems-tools/tree/linkers/rtld-trace-buffer.ini

You could add anything specific you want. It is not a great solution but
tracing into data being passed by pointers is difficult.

You would need to use the various options to get a copy of the trace
wrapper file and then get the generator to see the headers and various
data you want.

> If there isn't support already, maybe some parts of the trace
> infrastructure can be reused, notably the backed for storing the data,
> and/or sending it out over the network. Are there plans to make the
> Trace Linker natively output CTF data? 

We would like to support CTF output. Getting this done would need
developer funding.

> Perhaps barectf could be used for this purpose.

I do not know what this. Do you have a reference?

Chris