[PATCH v5 00/45] CPU hotplug: stop_machine()-free CPU hotplug

[Vincent Guittot]

On 18 February 2013 20:53, Steven Rostedt <rostedt at goodmis.org> wrote:
> On Mon, 2013-02-18 at 17:50 +0100, Vincent Guittot wrote:
>
>> yes for sure.
>> The problem is more linked to cpuidle and function tracer.
>>
>> cpu hotplug and function tracer work when cpuidle is disable.
>> cpu hotplug and cpuidle works if i don't enable function tracer.
>> my platform is dead as soon as I enable function tracer if cpuidle is
>> enabled. It looks like some notrace are missing in my platform driver
>> but we haven't completely fix the issue yet
>>
>
> You can bisect to find out exactly what function is the problem:
>
>  cat /debug/tracing/available_filter_functions > t
>
> f(t) {
>  num=`wc -l t`
>  sed -ne "1,${num}p" t > t1
>  let num=num+1
>  sed -ne "${num},$p" t > t2
>
>  cat t1 > /debug/tracing/set_ftrace_filter
>  # note this may take a long time to finish
>
>  echo function > /debug/tracing/current_tracer
>
>  <failed? bisect f(t1), if not bisect f(t2)>
> }
>

Thanks, i'm going to have a look

Vincent

> -- Steve
>
>
>