[PATCH] perf stat: Add Topdown metrics L2 events as default events
From: kan . liang
Date: Thu Jul 08 2021 - 12:04:35 EST
From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
The Topdown Microarchitecture Analysis (TMA) Method is a structured
analysis methodology to identify critical performance bottlenecks in
out-of-order processors. The Topdown metrics L1 event was added as
default events in the commit 42641d6f4d15 ("perf stat: Add Topdown
metrics events as default events"). From the Sapphire Rapids server and
later platforms, the same dedicated "metrics" register is extended to
support both L1 and L2 events. Add both L1 and L2 Topdown metrics events
as default events to enrich the default measuring information, if the
new measurement register is available. On legacy systems there is no
change to avoid extra multiplexing.
The topdown_level indicates the max metrics level for the top-down
statistics. Set it to 2 to display all L1 and L2 Topdown metrics events.
With the patch:
$ perf stat sleep 1
Performance counter stats for 'sleep 1':
0.59 msec task-clock # 0.001 CPUs utilized
1 context-switches # 1.687 K/sec
0 cpu-migrations # 0.000 /sec
76 page-faults # 128.198 K/sec
1,405,318 cycles # 2.371 GHz
1,471,136 instructions # 1.05 insn per cycle
310,132 branches # 523.136 M/sec
10,435 branch-misses # 3.36% of all branches
8,431,908 slots # 14.223 G/sec
1,554,116 topdown-retiring # 18.4% retiring
1,289,585 topdown-bad-spec # 15.2% bad speculation
2,810,636 topdown-fe-bound # 33.2% frontend bound
2,810,636 topdown-be-bound # 33.2% backend bound
231,464 topdown-heavy-ops # 2.7% heavy operations # 15.6% light operations
1,223,453 topdown-br-mispredict # 14.5% branch mispredict # 0.8% machine clears
1,884,779 topdown-fetch-lat # 22.3% fetch latency # 10.9% fetch bandwidth
1,454,917 topdown-mem-bound # 17.2% memory bound # 16.0% Core bound
1.001179699 seconds time elapsed
0.000000000 seconds user
0.001238000 seconds sys
Reviewed-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
---
tools/perf/arch/x86/util/evlist.c | 6 +++++-
tools/perf/builtin-stat.c | 3 +++
2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/tools/perf/arch/x86/util/evlist.c b/tools/perf/arch/x86/util/evlist.c
index 8c6732c..0b09510 100644
--- a/tools/perf/arch/x86/util/evlist.c
+++ b/tools/perf/arch/x86/util/evlist.c
@@ -5,11 +5,15 @@
#include "util/parse-events.h"
#define TOPDOWN_L1_EVENTS "{slots,topdown-retiring,topdown-bad-spec,topdown-fe-bound,topdown-be-bound}"
+#define TOPDOWN_L2_EVENTS "{slots,topdown-retiring,topdown-bad-spec,topdown-fe-bound,topdown-be-bound,topdown-heavy-ops,topdown-br-mispredict,topdown-fetch-lat,topdown-mem-bound}"
int arch_evlist__add_default_attrs(struct evlist *evlist)
{
if (!pmu_have_event("cpu", "slots"))
return 0;
- return parse_events(evlist, TOPDOWN_L1_EVENTS, NULL);
+ if (pmu_have_event("cpu", "topdown-heavy-ops"))
+ return parse_events(evlist, TOPDOWN_L2_EVENTS, NULL);
+ else
+ return parse_events(evlist, TOPDOWN_L1_EVENTS, NULL);
}
diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 5a830ae..a5e93d4 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -154,6 +154,8 @@ static const char *topdown_metric_L2_attrs[] = {
NULL,
};
+#define TOPDOWN_MAX_LEVEL 2
+
static const char *smi_cost_attrs = {
"{"
"msr/aperf/,"
@@ -1924,6 +1926,7 @@ static int add_default_attributes(void)
if (evlist__add_default_attrs(evsel_list, default_attrs1) < 0)
return -1;
+ stat_config.topdown_level = TOPDOWN_MAX_LEVEL;
if (arch_evlist__add_default_attrs(evsel_list) < 0)
return -1;
}
--
2.7.4