perf: Add perf_event::child_count
Only child counters adding back their values into the parent counter
are responsible for cross-cpu updates to event->count.
So if we pull that out into a new child_count variable, we get an
event->count that is only modified locally.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 441992a..f34dab9 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -671,6 +671,7 @@
enum perf_event_active_state state;
unsigned int attach_state;
atomic64_t count;
+ atomic64_t child_count;
/*
* These are the total time in nanoseconds that the event