[PATCH 1/5] perf events: Fix event inherit fallout of precalculated headers

[Arnaldo Carvalho de Melo <acme@infradead.org>]

From: Thomas Gleixner <tglx@linutronix.de>

The precalculated header size is not updated when an event is inherited. That
results in bogus sample entries for all child events. Bug introduced in c320c7b.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ian Munsie <imunsie@au1.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <alpine.LFD.2.00.1012031245220.2653@localhost6.localdomain6>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 kernel/perf_event.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index aede712..7961b27 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -6099,6 +6099,11 @@ inherit_event(struct perf_event *parent_event,
 	child_event->overflow_handler = parent_event->overflow_handler;
 
 	/*
+	 * Precalculate sample_data sizes
+	 */
+	perf_event__header_size(child_event);
+
+	/*
 	 * Link it up in the child's context:
 	 */
 	raw_spin_lock_irqsave(&child_ctx->lock, flags);
-- 
1.6.2.5