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From: Corey Ashford on 7 May 2010 22:00
Hi,

There appears to be a bug in the kernel related to reading up the time
running and enabled values for events that are in a group. The group
leader's time running and time enable values look correct, but all of
the other group members have a zero value for their time running and
time enabled fields.

This happens only when remote monitoring a process (perhaps only after
it has terminated)... when self monitoring, the time running/enabled
values come out non-zero, and the values are the same for all of the
counters (as one would expect since they can be enabled/disabled
simultaneously).

I've attached a test case which you can place in the tools/perf
subdirectory and compile with just:

gcc -o show_re_bug show_re_bug.c

Thanks for your consideration,

- Corey

Corey Ashford
Software Engineer
IBM Linux Technology Center, Linux Toolchain
Beaverton, OR
cjashfor(a)us.ibm.com
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