perf timechart broken

[Thomas Renninger <trenn@suse.de>]

Hi,

Latest x86 tip has another perf timechart issue introduce
by latest commits.

./perf timechart
gives me:
"no trace data in the file"

I reverted  the latest changes and things seem to break
between d854861c4292a4e675a5d3bfd862c5f7421c81e8
and
69aad6f1ee69546dea8535ab8f3da9f445d57328
(linux-2.6-x86 tree ids)

Be aware that ./perf timechart is currently broken
and segfaults on idle events (in 2.6.36 and 2.6.37).
I submitted a patch to stable@ but it did not get accepted,
becaust it's not mainline yet.
I concentrated on my latest patches instead of making sure
the tiny fix gets into 2.6.37 first.

Ingo: It's a bit late for 2.6.37, if there is any chance
to still get it in, the patch below is against linus master...
otherwise I'll submit it for stable 36+37 asap.

Anyway to test above regression this mail is about, first
apply below patch otherwise you get a segfault if idle
(power_start/end) events got logged.

Thanks,

   Thomas

---
perf timechart: Fix segfault on cpu idle (power_start/end) events

power_end event does not have type and other attributes and thus does
not match struct power_event.
Another struct could be created, but data.cpu is fine for fixing the segfault
and will work as long as C-states got initiated on the same CPU the idle state
takes place which is the case for all recent HW.

The power_start/end events get deprecated anyway, thus this is an easy,
riskless and sufficient solution for the segfault problem.

Signed-off-by: Thomas Renninger <trenn@suse.de>
CC: mingo@elte.hu
CC: arjan@linux.intel.com

---
 tools/perf/builtin-timechart.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/tools/perf/builtin-timechart.c b/tools/perf/builtin-timechart.c
index 9bcc38f..b3028eb 100644
--- a/tools/perf/builtin-timechart.c
+++ b/tools/perf/builtin-timechart.c
@@ -502,7 +502,7 @@ static int process_sample_event(event_t *event, struct perf_session *session)
 			c_state_start(pe->cpu_id, data.time, pe->value);
 
 		if (strcmp(event_str, "power:power_end") == 0)
-			c_state_end(pe->cpu_id, data.time);
+			c_state_end(data.cpu, data.time);
 
 		if (strcmp(event_str, "power:power_frequency") == 0)
 			p_state_change(pe->cpu_id, data.time, pe->value);