Messages in this thread | | | Date | Tue, 30 Nov 2010 17:00:16 -0800 | From | Corey Ashford <> | Subject | [BUG(?)] perf_events: combining multiple tracepoint events into a group produces no counts on member events |
| |
Hi,
I'm not sure that what I'm seeing is a bug, or was something intentional.
If I place multiple tracepoint events into a group and measure counts of these events on a process, I get no counts for the tracepoint events other than the group leader.
Is this expected behavior?
It's not clear to me why this should be the case; grouping shouldn't have any ill effects on tracepoint events, from my understanding.
I noticed this because my private version of the perf tool has the event group patch https://lkml.org/lkml/2010/11/24/584 as well as the patch which fixes the parsing of multiple tracepoint events in the same -e switch: https://lkml.org/lkml/2010/11/30/460
When I dig into the code a bit, I find that each event opens successfully, so that's not the problem. If I disable the grouping, then I get counts for all of the tracepoint events.
- Corey
| |