[PATCH v1 02/15] perf pmus: Fake PMU clean up

From: Ian Rogers
Date: Sat Sep 07 2024 - 01:09:22 EST

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Rather than passing a fake PMU around, just pass that the fake PMU
should be used - true when doing testing. Move the fake PMU into
pmus.[ch] and try to abstract the PMU's properties in pmu.c, ie so
there is less "if fake_pmu" in non-PMU code. Give the fake PMU a made
up type number.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/tests/parse-events.c | 4 ++--
tools/perf/tests/pmu-events.c | 12 +++++-------
tools/perf/util/metricgroup.c | 10 +++++-----
tools/perf/util/parse-events.c | 33 +++++++++++++++++----------------
tools/perf/util/parse-events.h | 8 ++++----
tools/perf/util/pmu.c | 21 +++++++++++++++------
tools/perf/util/pmu.h | 7 ++++---
tools/perf/util/pmus.c | 11 +++++++++++
tools/perf/util/pmus.h | 1 +
9 files changed, 64 insertions(+), 43 deletions(-)

diff --git a/tools/perf/tests/parse-events.c b/tools/perf/tests/parse-events.c
index edc2adcf1bae..a9a77dfe0e97 100644
--- a/tools/perf/tests/parse-events.c
+++ b/tools/perf/tests/parse-events.c
@@ -2500,7 +2500,7 @@ static int test_event(const struct evlist_test *e)
return TEST_FAIL;
}
parse_events_error__init(&err);
- ret = __parse_events(evlist, e->name, /*pmu_filter=*/NULL, &err, /*fake_pmu=*/NULL,
+ ret = __parse_events(evlist, e->name, /*pmu_filter=*/NULL, &err, /*fake_pmu=*/false,
/*warn_if_reordered=*/true, /*fake_tp=*/true);
if (ret) {
pr_debug("failed to parse event '%s', err %d\n", e->name, ret);
@@ -2529,7 +2529,7 @@ static int test_event_fake_pmu(const char *str)

parse_events_error__init(&err);
ret = __parse_events(evlist, str, /*pmu_filter=*/NULL, &err,
- &perf_pmu__fake, /*warn_if_reordered=*/true,
+ /*fake_pmu=*/true, /*warn_if_reordered=*/true,
/*fake_tp=*/true);
if (ret) {
pr_debug("failed to parse event '%s', err %d\n",
diff --git a/tools/perf/tests/pmu-events.c b/tools/perf/tests/pmu-events.c
index ff3e7bc0a77f..db004d26fcb0 100644
--- a/tools/perf/tests/pmu-events.c
+++ b/tools/perf/tests/pmu-events.c
@@ -819,8 +819,7 @@ static bool is_number(const char *str)
return errno == 0 && end_ptr != str;
}

-static int check_parse_id(const char *id, struct parse_events_error *error,
- struct perf_pmu *fake_pmu)
+static int check_parse_id(const char *id, struct parse_events_error *error)
{
struct evlist *evlist;
int ret;
@@ -841,7 +840,7 @@ static int check_parse_id(const char *id, struct parse_events_error *error,
for (cur = strchr(dup, '@') ; cur; cur = strchr(++cur, '@'))
*cur = '/';

- ret = __parse_events(evlist, dup, /*pmu_filter=*/NULL, error, fake_pmu,
+ ret = __parse_events(evlist, dup, /*pmu_filter=*/NULL, error, /*fake_pmu=*/true,
/*warn_if_reordered=*/true, /*fake_tp=*/false);
free(dup);

@@ -855,7 +854,7 @@ static int check_parse_fake(const char *id)
int ret;

parse_events_error__init(&error);
- ret = check_parse_id(id, &error, &perf_pmu__fake);
+ ret = check_parse_id(id, &error);
parse_events_error__exit(&error);
return ret;
}
@@ -1051,9 +1050,8 @@ static int test__parsing_fake_callback(const struct pmu_metric *pm,
}

/*
- * Parse all the metrics for current architecture,
- * or all defined cpus via the 'fake_pmu'
- * in parse_events.
+ * Parse all the metrics for current architecture, or all defined cpus via the
+ * 'fake_pmu' in parse_events.
*/
static int test__parsing_fake(struct test_suite *test __maybe_unused,
int subtest __maybe_unused)
diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
index 69f6a46402c3..4dff3e925a47 100644
--- a/tools/perf/util/metricgroup.c
+++ b/tools/perf/util/metricgroup.c
@@ -1436,7 +1436,7 @@ static int build_combined_expr_ctx(const struct list_head *metric_list,
* parse_ids - Build the event string for the ids and parse them creating an
* evlist. The encoded metric_ids are decoded.
* @metric_no_merge: is metric sharing explicitly disabled.
- * @fake_pmu: used when testing metrics not supported by the current CPU.
+ * @fake_pmu: use a fake PMU when testing metrics not supported by the current CPU.
* @ids: the event identifiers parsed from a metric.
* @modifier: any modifiers added to the events.
* @group_events: should events be placed in a weak group.
@@ -1444,7 +1444,7 @@ static int build_combined_expr_ctx(const struct list_head *metric_list,
* the overall list of metrics.
* @out_evlist: the created list of events.
*/
-static int parse_ids(bool metric_no_merge, struct perf_pmu *fake_pmu,
+static int parse_ids(bool metric_no_merge, bool fake_pmu,
struct expr_parse_ctx *ids, const char *modifier,
bool group_events, const bool tool_events[PERF_TOOL_MAX],
struct evlist **out_evlist)
@@ -1528,7 +1528,7 @@ static int parse_groups(struct evlist *perf_evlist,
bool metric_no_threshold,
const char *user_requested_cpu_list,
bool system_wide,
- struct perf_pmu *fake_pmu,
+ bool fake_pmu,
struct rblist *metric_events_list,
const struct pmu_metrics_table *table)
{
@@ -1703,7 +1703,7 @@ int metricgroup__parse_groups(struct evlist *perf_evlist,

return parse_groups(perf_evlist, pmu, str, metric_no_group, metric_no_merge,
metric_no_threshold, user_requested_cpu_list, system_wide,
- /*fake_pmu=*/NULL, metric_events, table);
+ /*fake_pmu=*/false, metric_events, table);
}

int metricgroup__parse_groups_test(struct evlist *evlist,
@@ -1717,7 +1717,7 @@ int metricgroup__parse_groups_test(struct evlist *evlist,
/*metric_no_threshold=*/false,
/*user_requested_cpu_list=*/NULL,
/*system_wide=*/false,
- &perf_pmu__fake, metric_events, table);
+ /*fake_pmu=*/true, metric_events, table);
}

struct metricgroup__has_metric_data {
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index fab01ba54e34..081ceff467f2 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -1478,8 +1478,8 @@ static int parse_events_add_pmu(struct parse_events_state *parse_state,
}

/* Look for event names in the terms and rewrite into format based terms. */
- if (!parse_state->fake_pmu && perf_pmu__check_alias(pmu, &parsed_terms,
- &info, &alias_rewrote_terms, err)) {
+ if (perf_pmu__check_alias(pmu, &parsed_terms,
+ &info, &alias_rewrote_terms, err)) {
parse_events_terms__exit(&parsed_terms);
return -EINVAL;
}
@@ -1515,8 +1515,7 @@ static int parse_events_add_pmu(struct parse_events_state *parse_state,
return -ENOMEM;
}

- if (!parse_state->fake_pmu &&
- perf_pmu__config(pmu, &attr, &parsed_terms, parse_state->error)) {
+ if (perf_pmu__config(pmu, &attr, &parsed_terms, parse_state->error)) {
free_config_terms(&config_terms);
parse_events_terms__exit(&parsed_terms);
return -EINVAL;
@@ -1536,11 +1535,6 @@ static int parse_events_add_pmu(struct parse_events_state *parse_state,

evsel->percore = config_term_percore(&evsel->config_terms);

- if (parse_state->fake_pmu) {
- parse_events_terms__exit(&parsed_terms);
- return 0;
- }
-
parse_events_terms__exit(&parsed_terms);
free((char *)evsel->unit);
evsel->unit = strdup(info.unit);
@@ -1616,13 +1610,13 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
}

if (parse_state->fake_pmu) {
- if (!parse_events_add_pmu(parse_state, list, parse_state->fake_pmu, &parsed_terms,
+ if (!parse_events_add_pmu(parse_state, list, perf_pmus__fake_pmu(), &parsed_terms,
/*auto_merge_stats=*/true)) {
struct strbuf sb;

strbuf_init(&sb, /*hint=*/ 0);
parse_events_terms__to_strbuf(&parsed_terms, &sb);
- pr_debug("%s -> %s/%s/\n", event_name, "fake_pmu", sb.buf);
+ pr_debug("%s -> fake/%s/\n", event_name, sb.buf);
strbuf_release(&sb);
ok++;
}
@@ -1656,11 +1650,18 @@ int parse_events_multi_pmu_add_or_add_pmu(struct parse_events_state *parse_state
INIT_LIST_HEAD(*listp);

/* Attempt to add to list assuming event_or_pmu is a PMU name. */
- pmu = parse_state->fake_pmu ?: perf_pmus__find(event_or_pmu);
+ pmu = perf_pmus__find(event_or_pmu);
if (pmu && !parse_events_add_pmu(parse_state, *listp, pmu, const_parsed_terms,
/*auto_merge_stats=*/false))
return 0;

+ if (parse_state->fake_pmu) {
+ if (!parse_events_add_pmu(parse_state, *listp, perf_pmus__fake_pmu(),
+ const_parsed_terms,
+ /*auto_merge_stats=*/false))
+ return 0;
+ }
+
pmu = NULL;
/* Failed to add, try wildcard expansion of event_or_pmu as a PMU name. */
while ((pmu = perf_pmus__scan(pmu)) != NULL) {
@@ -1961,8 +1962,8 @@ static int evsel__compute_group_pmu_name(struct evsel *evsel,
}
}
}
- /* Assign the actual name taking care that the fake PMU lacks a name. */
- evsel->group_pmu_name = strdup(group_pmu_name ?: "fake");
+ /* Record computed name. */
+ evsel->group_pmu_name = strdup(group_pmu_name);
return evsel->group_pmu_name ? 0 : -ENOMEM;
}

@@ -2124,7 +2125,7 @@ static int parse_events__sort_events_and_fix_groups(struct list_head *list)
}

int __parse_events(struct evlist *evlist, const char *str, const char *pmu_filter,
- struct parse_events_error *err, struct perf_pmu *fake_pmu,
+ struct parse_events_error *err, bool fake_pmu,
bool warn_if_reordered, bool fake_tp)
{
struct parse_events_state parse_state = {
@@ -2343,7 +2344,7 @@ int parse_events_option(const struct option *opt, const char *str,

parse_events_error__init(&err);
ret = __parse_events(*args->evlistp, str, args->pmu_filter, &err,
- /*fake_pmu=*/NULL, /*warn_if_reordered=*/true,
+ /*fake_pmu=*/false, /*warn_if_reordered=*/true,
/*fake_tp=*/false);

if (ret) {
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index b735cd9e0acf..bfbf391451d9 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -31,14 +31,14 @@ int parse_events_option(const struct option *opt, const char *str, int unset);
int parse_events_option_new_evlist(const struct option *opt, const char *str, int unset);
__attribute__((nonnull(1, 2, 4)))
int __parse_events(struct evlist *evlist, const char *str, const char *pmu_filter,
- struct parse_events_error *error, struct perf_pmu *fake_pmu,
+ struct parse_events_error *error, bool fake_pmu,
bool warn_if_reordered, bool fake_tp);

__attribute__((nonnull(1, 2, 3)))
static inline int parse_events(struct evlist *evlist, const char *str,
struct parse_events_error *err)
{
- return __parse_events(evlist, str, /*pmu_filter=*/NULL, err, /*fake_pmu=*/NULL,
+ return __parse_events(evlist, str, /*pmu_filter=*/NULL, err, /*fake_pmu=*/false,
/*warn_if_reordered=*/true, /*fake_tp=*/false);
}

@@ -150,8 +150,8 @@ struct parse_events_state {
struct parse_events_terms *terms;
/* Start token. */
int stoken;
- /* Special fake PMU marker for testing. */
- struct perf_pmu *fake_pmu;
+ /* Use the fake PMU marker for testing. */
+ bool fake_pmu;
/* Skip actual tracepoint processing for testing. */
bool fake_tp;
/* If non-null, when wildcard matching only match the given PMU. */
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 0b38c51bd6eb..50e2e7abffab 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -30,10 +30,6 @@
#include "util/evsel_config.h"
#include <regex.h>

-struct perf_pmu perf_pmu__fake = {
- .name = "fake",
-};
-
#define UNIT_MAX_LEN 31 /* max length for event unit name */

enum event_source {
@@ -1173,6 +1169,11 @@ struct perf_pmu *perf_pmu__create_placeholder_core_pmu(struct list_head *core_pm
return pmu;
}

+static bool perf_pmu__is_fake(const struct perf_pmu *pmu)
+{
+ return pmu->type == PERF_PMU_TYPE_FAKE;
+}
+
void perf_pmu__warn_invalid_formats(struct perf_pmu *pmu)
{
struct perf_pmu_format *format;
@@ -1183,7 +1184,7 @@ void perf_pmu__warn_invalid_formats(struct perf_pmu *pmu)
pmu->formats_checked = true;

/* fake pmu doesn't have format list */
- if (pmu == &perf_pmu__fake)
+ if (perf_pmu__is_fake(pmu))
return;

list_for_each_entry(format, &pmu->format, list) {
@@ -1511,6 +1512,10 @@ int perf_pmu__config(struct perf_pmu *pmu, struct perf_event_attr *attr,
{
bool zero = !!pmu->perf_event_attr_init_default;

+ /* Fake PMU doesn't have proper terms so nothing to configure in attr. */
+ if (perf_pmu__is_fake(pmu))
+ return 0;
+
return perf_pmu__config_terms(pmu, attr, head_terms, zero, err);
}

@@ -1619,6 +1624,10 @@ int perf_pmu__check_alias(struct perf_pmu *pmu, struct parse_events_terms *head_
info->scale = 0.0;
info->snapshot = false;

+ /* Fake PMU doesn't rewrite terms. */
+ if (perf_pmu__is_fake(pmu))
+ goto out;
+
list_for_each_entry_safe(term, h, &head_terms->terms, list) {
alias = pmu_find_alias(pmu, term);
if (!alias)
@@ -1641,7 +1650,7 @@ int perf_pmu__check_alias(struct perf_pmu *pmu, struct parse_events_terms *head_
list_del_init(&term->list);
parse_events_term__delete(term);
}
-
+out:
/*
* if no unit or scale found in aliases, then
* set defaults as for evsel
diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h
index b2d3fd291f02..d6f702e55a05 100644
--- a/tools/perf/util/pmu.h
+++ b/tools/perf/util/pmu.h
@@ -36,6 +36,10 @@ struct perf_pmu_caps {
struct list_head list;
};

+enum {
+ PERF_PMU_TYPE_FAKE = 0xFFFFFFFF,
+};
+
/**
* struct perf_pmu
*/
@@ -173,9 +177,6 @@ struct perf_pmu {
struct perf_mem_event *mem_events;
};

-/** @perf_pmu__fake: A special global PMU used for testing. */
-extern struct perf_pmu perf_pmu__fake;
-
struct perf_pmu_info {
const char *unit;
double scale;
diff --git a/tools/perf/util/pmus.c b/tools/perf/util/pmus.c
index 3fcabfd8fca1..864cbfa1f960 100644
--- a/tools/perf/util/pmus.c
+++ b/tools/perf/util/pmus.c
@@ -720,3 +720,14 @@ struct perf_pmu *perf_pmus__add_test_pmu(int test_sysfs_dirfd, const char *name)
*/
return perf_pmu__lookup(&other_pmus, test_sysfs_dirfd, name, /*eager_load=*/true);
}
+
+struct perf_pmu *perf_pmus__fake_pmu(void)
+{
+ static struct perf_pmu fake = {
+ .name = "fake",
+ .type = PERF_PMU_TYPE_FAKE,
+ .format = LIST_HEAD_INIT(fake.format),
+ };
+
+ return &fake;
+}
diff --git a/tools/perf/util/pmus.h b/tools/perf/util/pmus.h
index bdbff02324bb..e1742b56eec7 100644
--- a/tools/perf/util/pmus.h
+++ b/tools/perf/util/pmus.h
@@ -30,5 +30,6 @@ bool perf_pmus__supports_extended_type(void);
char *perf_pmus__default_pmu_name(void);

struct perf_pmu *perf_pmus__add_test_pmu(int test_sysfs_dirfd, const char *name);
+struct perf_pmu *perf_pmus__fake_pmu(void);

#endif /* __PMUS_H */
--
2.46.0.469.g59c65b2a67-goog

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