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    SubjectRe: [BUG] perf_event: when events are grouped, the time enabled / running values are incorrect
    On 05/07/2010 06:56 PM, Corey Ashford wrote:
    > 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

    I forgot to mention that you should run this with some sort of the load
    program, like

    ./show_re_bug md5sum `which gdb`

    - Corey


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