Re: Tracing of power:power_start events doesn't work

["Ronny Tschüter" <Ronny.Tschueter@tu-dresden.de>]

On Wed 2010-05-05 02:31, Steven Rostedt wrote:
> On Mon, 2010-05-03 at 15:19 +0200, Ronny Tschüter wrote:
>    
>> Hello,
>>
>> i use kernel version 2.6.33.2 (x86-64, Core 2 Duo) and the perf events
>> to track frequency and c states of my cpu. But if i want to trace
>> power:power_start events, it does not work. After typing
>>
>> echo "power:power_start" | sudo tee set_event
>>
>> on the console, the trace doesn't contain such events.
>> power:power_frequency and power:power_end events are reported correctly
>> by the system. I read in the mailing list that Robert Schoene had a
>> similiar problem, but with power:power_end events. Is there a known bug
>> regarding to trace_power_start methods in process.c?
>>      
> Is this for perf or ftrace? I'm assuming you did this from the debugfs
> tracing directory. The set_event file is for ftrace not perf.
>    
It is for perf - i'm interested in event tracing. I used the event 
tracing system like it is described in Documentation/trace/events.txt. 
In addition i wrote a program which uses syscall(__NR_perf_counter_open, 
... ) to trace power events. But the result is the same - 
power:power_end events are reported, power:power_start events not.

Bye Ronny