If we leave the event in STATE_INACTIVE, any read of the event after the detach will increase the running count but not the enabled count and cause funny scaling artefacts. Signed-off-by: Peter Zijlstra --- kernel/perf_event.c | 2 ++ 1 file changed, 2 insertions(+) Index: linux-2.6/kernel/perf_event.c =================================================================== --- linux-2.6.orig/kernel/perf_event.c +++ linux-2.6/kernel/perf_event.c @@ -294,6 +294,8 @@ list_del_event(struct perf_event *event, if (event->group_leader != event) event->group_leader->nr_siblings--; + event->state = PERF_EVENT_STATE_OFF; + /* * If this was a group event with sibling events then * upgrade the siblings to singleton events by adding them -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/