From 580d607cd666dfabfc1c7b0fb08c8ac690c7c87f Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
Date: Thu, 20 May 2010 20:54:31 +0200
Subject: [PATCH] perf: Optimize perf_tp_event_match()
Since we know tracepoints come from kernel context,
avoid conditionals that try and establish that very
fact.
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: <20100521090710.904944001@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
kernel/perf_event.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index d25c864cadbf9..e099650cd249a 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -4496,7 +4496,10 @@ static int perf_tp_event_match(struct perf_event *event,
struct perf_sample_data *data,
struct pt_regs *regs)
{
- if (perf_exclude_event(event, regs))
+ /*
+ * All tracepoints are from kernel-space.
+ */
+ if (event->attr.exclude_kernel)
return 0;
if (!perf_tp_filter_match(event, data))