[tip:perf/core] perf: Optimize perf_tp_event_match()

From: tip-bot for Peter Zijlstra
Date: Fri May 21 2010 - 07:31:13 EST


Commit-ID: 580d607cd666dfabfc1c7b0fb08c8ac690c7c87f
Gitweb: http://git.kernel.org/tip/580d607cd666dfabfc1c7b0fb08c8ac690c7c87f
Author: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
AuthorDate: Thu, 20 May 2010 20:54:31 +0200
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Fri, 21 May 2010 11:38:00 +0200

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@xxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
LKML-Reference: <20100521090710.904944001@xxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
---
kernel/perf_event.c | 5 ++++-
1 files changed, 4 insertions(+), 1 deletions(-)

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))
--
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