[PATCH 4/4 v3] perf stat: Add transaction flag (-T) support for s390

From: Thomas Richter
Date: Mon Jun 25 2018 - 08:59:10 EST


perf stat command line flag -T to display transaction counters is
currently supported for x86 only.
Add support for s390. It is based on the metrics flag -M transaction
using the architecture dependend json files. This requires a metric
named "transaction" in the json files for the platform.

v2 --> v3:
Introduce new function metricgroup__has_metric() to check for
the existance of a metric named transaction.

As suggested by Andi Kleen, this is the new approach to support
transactions counters. Other architectures will follow.

Output before:
[root@p23lp27 perf]# ./perf stat -T -- sleep 1
Cannot set up transaction events
[root@p23lp27 perf]#

Output after:
[root@s35lp76 perf]# ./perf stat -T -- ~/mytesttx 1 >/tmp/111

Performance counter stats for '/root/mytesttx 1':

1 tx_c_tend # 13.0 transaction
1 tx_nc_tend
11 tx_nc_tabort
0 tx_c_tabort_special
0 tx_c_tabort_no_special

0.001070109 seconds time elapsed

[root@s35lp76 perf]#

Suggested-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Signed-off-by: Thomas Richter <tmricht@xxxxxxxxxxxxx>
Suggested-by: Hendrik Brueckner <brueckner@xxxxxxxxxxxxx>
Reviewed-by: Hendrik Brueckner <brueckner@xxxxxxxxxxxxx>
---
tools/perf/builtin-stat.c | 12 ++++++++++++
tools/perf/util/metricgroup.c | 23 +++++++++++++++++++++++
tools/perf/util/metricgroup.h | 1 +
3 files changed, 36 insertions(+)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index a4f662a462c6..e309279e7b04 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -2425,6 +2425,18 @@ static int add_default_attributes(void)
if (transaction_run) {
struct parse_events_error errinfo;

+ /* Handle -T as -M transaction. Once platform specific metrics
+ * support has been added to the json files, all archictures
+ * will use this approach. To determine transaction support
+ * on an architecture test for such a metric name.
+ */
+ if (metricgroup__has_metric("transaction")) {
+ struct option opt = { .value = &evsel_list };
+
+ return metricgroup__parse_groups(&opt, "transaction",
+ &metric_events);
+ }
+
if (pmu_have_event("cpu", "cycles-ct") &&
pmu_have_event("cpu", "el-start"))
err = parse_events(evsel_list, transaction_attrs,
diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
index 1ddc3d1d0147..90cff5226ecc 100644
--- a/tools/perf/util/metricgroup.c
+++ b/tools/perf/util/metricgroup.c
@@ -490,3 +490,26 @@ int metricgroup__parse_groups(const struct option *opt,
metricgroup__free_egroups(&group_list);
return ret;
}
+
+bool metricgroup__has_metric(const char *metric)
+{
+ struct pmu_events_map *map = perf_pmu__find_map(NULL);
+ struct pmu_event *pe;
+ int i;
+
+ if (!map)
+ return false;
+
+ for (i = 0; ; i++) {
+ pe = &map->table[i];
+
+ if (!pe->name && !pe->metric_group && !pe->metric_name)
+ break;
+ if (!pe->metric_expr)
+ continue;
+ if (match_metric(pe->metric_group, metric) ||
+ match_metric(pe->metric_name, metric))
+ return true;
+ }
+ return false;
+}
diff --git a/tools/perf/util/metricgroup.h b/tools/perf/util/metricgroup.h
index 06854e125ee7..8a155dba0581 100644
--- a/tools/perf/util/metricgroup.h
+++ b/tools/perf/util/metricgroup.h
@@ -28,4 +28,5 @@ int metricgroup__parse_groups(const struct option *opt,
struct rblist *metric_events);

void metricgroup__print(bool metrics, bool groups, char *filter, bool raw);
+bool metricgroup__has_metric(const char *metric);
#endif
--
2.14.3