[PATCH v5 1/4] perf stat: Basic support for iostat in perf

From: Alexander Antonov
Date: Wed Mar 24 2021 - 10:31:47 EST

Add basic flow for a new iostat mode in perf. Mode is intended to
provide four I/O performance metrics per each PCIe root port: Inbound Read,
Inbound Write, Outbound Read, Outbound Write.

The actual code to compute the metrics and attribute it to
root port is in follow-on patches.

Signed-off-by: Alexander Antonov <alexander.antonov@xxxxxxxxxxxxxxx>
---
tools/perf/builtin-stat.c | 21 +++++++++++++-
tools/perf/util/Build | 1 +
tools/perf/util/iostat.c | 53 ++++++++++++++++++++++++++++++++++
tools/perf/util/iostat.h | 47 ++++++++++++++++++++++++++++++
tools/perf/util/stat-display.c | 40 ++++++++++++++++++-------
tools/perf/util/stat-shadow.c | 5 +++-
tools/perf/util/stat.h | 1 +
7 files changed, 156 insertions(+), 12 deletions(-)
create mode 100644 tools/perf/util/iostat.c
create mode 100644 tools/perf/util/iostat.h

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 2e2e4a8345ea..4cef64ce9261 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -68,6 +68,7 @@
#include "util/affinity.h"
#include "util/pfm.h"
#include "util/bpf_counter.h"
+#include "util/iostat.h"
#include "asm/bug.h"

#include <linux/time64.h>
@@ -212,7 +213,8 @@ static struct perf_stat_config stat_config = {
.walltime_nsecs_stats = &walltime_nsecs_stats,
.big_num = true,
.ctl_fd = -1,
- .ctl_fd_ack = -1
+ .ctl_fd_ack = -1,
+ .iostat_run = false,
};

static bool cpus_map_matched(struct evsel *a, struct evsel *b)
@@ -1247,6 +1249,9 @@ static struct option stat_options[] = {
"\t\t\t Optionally send control command completion ('ack\\n') to ack-fd descriptor.\n"
"\t\t\t Alternatively, ctl-fifo / ack-fifo will be opened and used as ctl-fd / ack-fd.",
parse_control_option),
+ OPT_CALLBACK_OPTARG(0, "iostat", &evsel_list, &stat_config, "default",
+ "measure I/O performance metrics provided by arch/platform",
+ iostat_parse),
OPT_END()
};

@@ -2320,6 +2325,17 @@ int cmd_stat(int argc, const char **argv)
goto out;
}

+ if (stat_config.iostat_run) {
+ status = iostat_prepare(evsel_list, &stat_config);
+ if (status)
+ goto out;
+ if (iostat_mode == IOSTAT_LIST) {
+ iostat_list(evsel_list, &stat_config);
+ goto out;
+ } else if (verbose)
+ iostat_list(evsel_list, &stat_config);
+ }
+
if (add_default_attributes())
goto out;

@@ -2495,6 +2511,9 @@ int cmd_stat(int argc, const char **argv)
perf_stat__exit_aggr_mode();
evlist__free_stats(evsel_list);
out:
+ if (stat_config.iostat_run)
+ iostat_release(evsel_list);
+
zfree(&stat_config.walltime_run);

if (smi_cost && smi_reset)
diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index e3e12f9d4733..7dd815712d60 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -102,6 +102,7 @@ perf-y += rwsem.o
perf-y += thread-stack.o
perf-y += spark.o
perf-y += topdown.o
+perf-y += iostat.o
perf-y += stream.o
perf-$(CONFIG_AUXTRACE) += auxtrace.o
perf-$(CONFIG_AUXTRACE) += intel-pt-decoder/
diff --git a/tools/perf/util/iostat.c b/tools/perf/util/iostat.c
new file mode 100644
index 000000000000..57dd49da28fe
--- /dev/null
+++ b/tools/perf/util/iostat.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "util/iostat.h"
+#include "util/debug.h"
+
+enum iostat_mode_t iostat_mode = IOSTAT_NONE;
+
+__weak int iostat_prepare(struct evlist *evlist __maybe_unused,
+ struct perf_stat_config *config __maybe_unused)
+{
+ return -1;
+}
+
+__weak int iostat_parse(const struct option *opt __maybe_unused,
+ const char *str __maybe_unused,
+ int unset __maybe_unused)
+{
+ pr_err("iostat mode is not supported on current platform\n");
+ return -1;
+}
+
+__weak void iostat_list(struct evlist *evlist __maybe_unused,
+ struct perf_stat_config *config __maybe_unused)
+{
+}
+
+__weak void iostat_release(struct evlist *evlist __maybe_unused)
+{
+}
+
+__weak void iostat_print_header_prefix(struct perf_stat_config *config __maybe_unused)
+{
+}
+
+__weak void iostat_print_metric(struct perf_stat_config *config __maybe_unused,
+ struct evsel *evsel __maybe_unused,
+ struct perf_stat_output_ctx *out __maybe_unused)
+{
+}
+
+__weak void iostat_prefix(struct evlist *evlist __maybe_unused,
+ struct perf_stat_config *config __maybe_unused,
+ char *prefix __maybe_unused,
+ struct timespec *ts __maybe_unused)
+{
+}
+
+__weak void iostat_print_counters(struct evlist *evlist __maybe_unused,
+ struct perf_stat_config *config __maybe_unused,
+ struct timespec *ts __maybe_unused,
+ char *prefix __maybe_unused,
+ iostat_print_counter_t print_cnt_cb __maybe_unused)
+{
+}
diff --git a/tools/perf/util/iostat.h b/tools/perf/util/iostat.h
new file mode 100644
index 000000000000..23c1c46a331a
--- /dev/null
+++ b/tools/perf/util/iostat.h
@@ -0,0 +1,47 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * perf iostat
+ *
+ * Copyright (C) 2020, Intel Corporation
+ *
+ * Authors: Alexander Antonov <alexander.antonov@xxxxxxxxxxxxxxx>
+ */
+
+#ifndef _IOSTAT_H
+#define _IOSTAT_H
+
+#include <subcmd/parse-options.h>
+#include "util/stat.h"
+#include "util/parse-events.h"
+#include "util/evlist.h"
+
+struct option;
+struct perf_stat_config;
+struct evlist;
+struct timespec;
+
+enum iostat_mode_t {
+ IOSTAT_NONE = -1,
+ IOSTAT_RUN = 0,
+ IOSTAT_LIST = 1
+};
+
+extern enum iostat_mode_t iostat_mode;
+
+typedef void (*iostat_print_counter_t)(struct perf_stat_config *, struct evsel *, char *);
+
+int iostat_prepare(struct evlist *evlist, struct perf_stat_config *config);
+int iostat_parse(const struct option *opt, const char *str,
+ int unset __maybe_unused);
+void iostat_list(struct evlist *evlist, struct perf_stat_config *config);
+void iostat_release(struct evlist *evlist);
+void iostat_prefix(struct evlist *evlist, struct perf_stat_config *config,
+ char *prefix, struct timespec *ts);
+void iostat_print_header_prefix(struct perf_stat_config *config);
+void iostat_print_metric(struct perf_stat_config *config, struct evsel *evsel,
+ struct perf_stat_output_ctx *out);
+void iostat_print_counters(struct evlist *evlist,
+ struct perf_stat_config *config, struct timespec *ts,
+ char *prefix, iostat_print_counter_t print_cnt_cb);
+
+#endif /* _IOSTAT_H */
diff --git a/tools/perf/util/stat-display.c b/tools/perf/util/stat-display.c
index 7f09cdaf5b60..aabe78dc6836 100644
--- a/tools/perf/util/stat-display.c
+++ b/tools/perf/util/stat-display.c
@@ -17,6 +17,7 @@
#include "cgroup.h"
#include <api/fs/fs.h>
#include "util.h"
+#include "iostat.h"

#define CNTR_NOT_SUPPORTED "<not supported>"
#define CNTR_NOT_COUNTED "<not counted>"
@@ -310,6 +311,11 @@ static void print_metric_header(struct perf_stat_config *config,
struct outstate *os = ctx;
char tbuf[1024];

+ /* In case of iostat, print metric header for first root port only */
+ if (config->iostat_run &&
+ os->evsel->priv != os->evsel->evlist->selected->priv)
+ return;
+
if (!valid_only_metric(unit))
return;
unit = fixunit(tbuf, os->evsel, unit);
@@ -952,8 +958,11 @@ static void print_metric_headers(struct perf_stat_config *config,
if (config->csv_output) {
if (config->interval)
fputs("time,", config->output);
- fputs(aggr_header_csv[config->aggr_mode], config->output);
+ if (!config->iostat_run)
+ fputs(aggr_header_csv[config->aggr_mode], config->output);
}
+ if (config->iostat_run)
+ iostat_print_header_prefix(config);

/* Print metrics headers only */
evlist__for_each_entry(evlist, counter) {
@@ -983,7 +992,8 @@ static void print_interval(struct perf_stat_config *config,
if (config->interval_clear)
puts(CONSOLE_CLEAR);

- sprintf(prefix, "%6lu.%09lu%s", (unsigned long) ts->tv_sec, ts->tv_nsec, config->csv_sep);
+ if (!config->iostat_run)
+ sprintf(prefix, "%6lu.%09lu%s", (unsigned long) ts->tv_sec, ts->tv_nsec, config->csv_sep);

if ((num_print_interval == 0 && !config->csv_output) || config->interval_clear) {
switch (config->aggr_mode) {
@@ -1019,9 +1029,11 @@ static void print_interval(struct perf_stat_config *config,
break;
case AGGR_GLOBAL:
default:
- fprintf(output, "# time");
- if (!metric_only)
- fprintf(output, " counts %*s events\n", unit_width, "unit");
+ if (!config->iostat_run) {
+ fprintf(output, "# time");
+ if (!metric_only)
+ fprintf(output, " counts %*s events\n", unit_width, "unit");
+ }
case AGGR_UNSET:
break;
}
@@ -1214,6 +1226,9 @@ void evlist__print_counters(struct evlist *evlist, struct perf_stat_config *conf
struct evsel *counter;
char buf[64], *prefix = NULL;

+ if (config->iostat_run)
+ evlist->selected = evlist__first(evlist);
+
if (interval)
print_interval(config, evlist, prefix = buf, ts);
else
@@ -1226,7 +1241,7 @@ void evlist__print_counters(struct evlist *evlist, struct perf_stat_config *conf
print_metric_headers(config, evlist, prefix, false);
if (num_print_iv++ == 25)
num_print_iv = 0;
- if (config->aggr_mode == AGGR_GLOBAL && prefix)
+ if (config->aggr_mode == AGGR_GLOBAL && prefix && !config->iostat_run)
fprintf(config->output, "%s", prefix);
}

@@ -1243,11 +1258,16 @@ void evlist__print_counters(struct evlist *evlist, struct perf_stat_config *conf
}
break;
case AGGR_GLOBAL:
- evlist__for_each_entry(evlist, counter) {
- print_counter_aggr(config, counter, prefix);
+ if (config->iostat_run)
+ iostat_print_counters(evlist, config, ts, prefix = buf,
+ print_counter_aggr);
+ else {
+ evlist__for_each_entry(evlist, counter) {
+ print_counter_aggr(config, counter, prefix);
+ }
+ if (metric_only)
+ fputc('\n', config->output);
}
- if (metric_only)
- fputc('\n', config->output);
break;
case AGGR_NONE:
if (metric_only)
diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
index 3f800e71126f..39967a45f55b 100644
--- a/tools/perf/util/stat-shadow.c
+++ b/tools/perf/util/stat-shadow.c
@@ -11,6 +11,7 @@
#include "cgroup.h"
#include "units.h"
#include <linux/zalloc.h>
+#include "iostat.h"

/*
* AGGR_GLOBAL: Use CPU 0
@@ -962,7 +963,9 @@ void perf_stat__print_shadow_stats(struct perf_stat_config *config,
struct metric_event *me;
int num = 1;

- if (evsel__match(evsel, HARDWARE, HW_INSTRUCTIONS)) {
+ if (config->iostat_run) {
+ iostat_print_metric(config, evsel, out);
+ } else if (evsel__match(evsel, HARDWARE, HW_INSTRUCTIONS)) {
total = runtime_stat_avg(st, STAT_CYCLES, cpu, &rsd);

if (total) {
diff --git a/tools/perf/util/stat.h b/tools/perf/util/stat.h
index 41107b8deac5..96ed00eb609e 100644
--- a/tools/perf/util/stat.h
+++ b/tools/perf/util/stat.h
@@ -132,6 +132,7 @@ struct perf_stat_config {
bool metric_no_merge;
bool stop_read_counter;
bool quiet;
+ bool iostat_run;
FILE *output;
unsigned int interval;
unsigned int timeout;
--
2.19.1