Re: [PATCH][RFC 2/23]: SCST core

Frédéric Weisbecker
2008-12-13T01:28:03Z

2008/12/13 Frédéric Weisbecker <fweisbec@gmail.com>:
> 2008/12/13 Arnaldo Carvalho de Melo <acme@redhat.com>:
>> Steven, is it possible to trigger tracing for any function when a
>> function in the list set up by the user is running and then stop tracing
>> when it exits?
>>
>> - Arnaldo
>>
>
> Hi Arnaldo,
>
> Yes it's possible with ftrace, by using the function graph tracer ( an
> ftrace extension that adds the tracing on return).
>
> To enable it just do:
> echo function_graph > /debugfs/tracing/current_tracer
>
> And to trace by choosing a particular function as the root of the call
> stack, just do the things
> explained on this patch:
> http://git.kernel.org/?p=linux/kernel/git/mingo/linux-2.6-sched-devel.git;a=commit;h=ea4e2bc4d9f7370e57a343ccb5e7c0ad3222ec3c
>
> And the tracing will finish after this function returns :-)
>

I forgot to say that add-on is not yet included on 2.6.28
This will be available for 2.6.29.