From: Peter Zijlstra <a.p.zijlstra@chello.nl>
Date: Thu, 20 May 2010 18:54:31 +0000 (+0200)
Subject: perf: Optimize perf_tp_event_match()
X-Git-Tag: accepted/tizen/common/20141203.182822~11245^2~12
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=580d607cd666dfabfc1c7b0fb08c8ac690c7c87f;p=platform%2Fkernel%2Flinux-arm64.git

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>
---

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index d25c864..e099650 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))