linux-kernel - [PATCH v4 09/10] perf: optimize event_filter_match during sched

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Date:   Fri, 15 Nov 2019 17:18:44 -0800
From:   Ian Rogers <irogers@...gle.com>
To:     Peter Zijlstra <peterz@...radead.org>,
        Ingo Molnar <mingo@...hat.com>,
        Arnaldo Carvalho de Melo <acme@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
        Jiri Olsa <jolsa@...hat.com>,
        Namhyung Kim <namhyung@...nel.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Masahiro Yamada <yamada.masahiro@...ionext.com>,
        Kees Cook <keescook@...omium.org>,
        Catalin Marinas <catalin.marinas@....com>,
        Petr Mladek <pmladek@...e.com>,
        Mauro Carvalho Chehab <mchehab+samsung@...nel.org>,
        Qian Cai <cai@....pw>, Joe Lawrence <joe.lawrence@...hat.com>,
        Tetsuo Handa <penguin-kernel@...ove.sakura.ne.jp>,
        "Uladzislau Rezki (Sony)" <urezki@...il.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Ard Biesheuvel <ardb@...nel.org>,
        "David S. Miller" <davem@...emloft.net>,
        Kent Overstreet <kent.overstreet@...il.com>,
        Gary Hook <Gary.Hook@....com>, Arnd Bergmann <arnd@...db.de>,
        Kan Liang <kan.liang@...ux.intel.com>,
        linux-kernel@...r.kernel.org
Cc:     Stephane Eranian <eranian@...gle.com>,
        Andi Kleen <ak@...ux.intel.com>,
        Ian Rogers <irogers@...gle.com>
Subject: [PATCH v4 09/10] perf: optimize event_filter_match during sched_in

The caller verified the CPU and cgroup so directly call
pmu_filter_match.

Signed-off-by: Ian Rogers <irogers@...gle.com>
---
 kernel/events/core.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 37abfca18bd3..6427b16c95d0 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -2212,8 +2212,11 @@ static inline int pmu_filter_match(struct perf_event *event)
 static inline int
 event_filter_match(struct perf_event *event)
 {
-	return (event->cpu == -1 || event->cpu == smp_processor_id()) &&
-	       perf_cgroup_match(event) && pmu_filter_match(event);
+	if (event->cpu != -1 && event->cpu != smp_processor_id())
+		return 0;
+	if (!perf_cgroup_match(event))
+		return 0;
+	return pmu_filter_match(event);
 }
 
 static void
@@ -3562,7 +3565,11 @@ static int merge_sched_in(struct perf_event_context *ctx,
 	if (event->state <= PERF_EVENT_STATE_OFF)
 		return 0;
 
-	if (!event_filter_match(event))
+	/*
+	 * Avoid full event_filter_match as the caller verified the CPU and
+	 * cgroup before calling.
+	 */
+	if (!pmu_filter_match(event))
 		return 0;
 
 	if (group_can_go_on(event, cpuctx, 1)) {
-- 
2.24.0.432.g9d3f5f5b63-goog