[PATCH v5 10/14] perf pmu-events: Don't assume pmu_event is an array

From: Ian Rogers
Date: Fri Aug 12 2022 - 19:11:13 EST


Current code assumes that a struct pmu_event can be iterated over
forward until a NULL pmu_event is encountered. This makes it difficult
to refactor pmu_event. Add a loop function taking a callback function
that's passed the struct pmu_event. This way the pmu_event is only
needed for one element and not an entire array.

Switch existing code iterating over the pmu_event arrays to use the new
loop function pmu_events_table_for_each_event.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/pmu-events/empty-pmu-events.c | 34 +++--
tools/perf/pmu-events/jevents.py | 34 +++--
tools/perf/pmu-events/pmu-events.h | 3 +
tools/perf/tests/pmu-events.c | 136 +++++++++--------
tools/perf/util/metricgroup.c | 181 ++++++++++++++++-------
tools/perf/util/pmu.c | 65 ++++----
tools/perf/util/s390-sample-raw.c | 42 ++++--
7 files changed, 313 insertions(+), 182 deletions(-)

diff --git a/tools/perf/pmu-events/empty-pmu-events.c b/tools/perf/pmu-events/empty-pmu-events.c
index 028f44efe48d..bee1967baa2b 100644
--- a/tools/perf/pmu-events/empty-pmu-events.c
+++ b/tools/perf/pmu-events/empty-pmu-events.c
@@ -247,6 +247,20 @@ static const struct pmu_sys_events pmu_sys_event_tables[] = {
},
};

+int pmu_events_table_for_each_event(const struct pmu_event *table, pmu_event_iter_fn fn,
+ void *data)
+{
+ for (const struct pmu_event *pe = &table[0];
+ pe->name || pe->metric_group || pe->metric_name;
+ pe++) {
+ int ret = fn(pe, table, data);
+
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
const struct pmu_event *perf_pmu__find_table(struct perf_pmu *pmu)
{
const struct pmu_event *table = NULL;
@@ -291,14 +305,10 @@ int pmu_for_each_core_event(pmu_event_iter_fn fn, void *data)
for (const struct pmu_events_map *tables = &pmu_events_map[0];
tables->table;
tables++) {
- for (const struct pmu_event *pe = &tables->table[0];
- pe->name || pe->metric_group || pe->metric_name;
- pe++) {
- int ret = fn(pe, &tables->table[0], data);
+ int ret = pmu_events_table_for_each_event(tables->table, fn, data);

- if (ret)
- return ret;
- }
+ if (ret)
+ return ret;
}
return 0;
}
@@ -319,14 +329,10 @@ int pmu_for_each_sys_event(pmu_event_iter_fn fn, void *data)
for (const struct pmu_sys_events *tables = &pmu_sys_event_tables[0];
tables->name;
tables++) {
- for (const struct pmu_event *pe = &tables->table[0];
- pe->name || pe->metric_group || pe->metric_name;
- pe++) {
- int ret = fn(pe, &tables->table[0], data);
+ int ret = pmu_events_table_for_each_event(tables->table, fn, data);

- if (ret)
- return ret;
- }
+ if (ret)
+ return ret;
}
return 0;
}
diff --git a/tools/perf/pmu-events/jevents.py b/tools/perf/pmu-events/jevents.py
index 1a04b848d736..977f2061a990 100755
--- a/tools/perf/pmu-events/jevents.py
+++ b/tools/perf/pmu-events/jevents.py
@@ -410,6 +410,20 @@ static const struct pmu_sys_events pmu_sys_event_tables[] = {
\t},
};

+int pmu_events_table_for_each_event(const struct pmu_event *table, pmu_event_iter_fn fn,
+ void *data)
+{
+ for (const struct pmu_event *pe = &table[0];
+ pe->name || pe->metric_group || pe->metric_name;
+ pe++) {
+ int ret = fn(pe, table, data);
+
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
const struct pmu_event *perf_pmu__find_table(struct perf_pmu *pmu)
{
const struct pmu_event *table = NULL;
@@ -453,14 +467,10 @@ int pmu_for_each_core_event(pmu_event_iter_fn fn, void *data)
for (const struct pmu_events_map *tables = &pmu_events_map[0];
tables->table;
tables++) {
- for (const struct pmu_event *pe = &tables->table[0];
- pe->name || pe->metric_group || pe->metric_name;
- pe++) {
- int ret = fn(pe, &tables->table[0], data);
+ int ret = pmu_events_table_for_each_event(tables->table, fn, data);

- if (ret)
- return ret;
- }
+ if (ret)
+ return ret;
}
return 0;
}
@@ -481,14 +491,10 @@ int pmu_for_each_sys_event(pmu_event_iter_fn fn, void *data)
for (const struct pmu_sys_events *tables = &pmu_sys_event_tables[0];
tables->name;
tables++) {
- for (const struct pmu_event *pe = &tables->table[0];
- pe->name || pe->metric_group || pe->metric_name;
- pe++) {
- int ret = fn(pe, &tables->table[0], data);
+ int ret = pmu_events_table_for_each_event(tables->table, fn, data);

- if (ret)
- return ret;
- }
+ if (ret)
+ return ret;
}
return 0;
}
diff --git a/tools/perf/pmu-events/pmu-events.h b/tools/perf/pmu-events/pmu-events.h
index 485e730f9922..70672842f77f 100644
--- a/tools/perf/pmu-events/pmu-events.h
+++ b/tools/perf/pmu-events/pmu-events.h
@@ -34,6 +34,9 @@ typedef int (*pmu_event_iter_fn)(const struct pmu_event *pe,
const struct pmu_event *table,
void *data);

+int pmu_events_table_for_each_event(const struct pmu_event *table, pmu_event_iter_fn fn,
+ void *data);
+
const struct pmu_event *perf_pmu__find_table(struct perf_pmu *pmu);
const struct pmu_event *find_core_events_table(const char *arch, const char *cpuid);
int pmu_for_each_core_event(pmu_event_iter_fn fn, void *data);
diff --git a/tools/perf/tests/pmu-events.c b/tools/perf/tests/pmu-events.c
index a64497cb9fb2..e308d480f0fb 100644
--- a/tools/perf/tests/pmu-events.c
+++ b/tools/perf/tests/pmu-events.c
@@ -423,84 +423,104 @@ static int compare_alias_to_test_event(struct perf_pmu_alias *alias,
return 0;
}

-/* Verify generated events from pmu-events.c are as expected */
-static int test__pmu_event_table(struct test_suite *test __maybe_unused,
- int subtest __maybe_unused)
+static int test__pmu_event_table_core_callback(const struct pmu_event *pe,
+ const struct pmu_event *table __maybe_unused,
+ void *data)
{
- const struct pmu_event *sys_event_tables = find_sys_events_table("pme_test_soc_sys");
- const struct pmu_event *table = find_core_events_table("testarch", "testcpu");
- int map_events = 0, expected_events;
+ int *map_events = data;
+ struct perf_pmu_test_event const **test_event_table;
+ bool found = false;

- /* ignore 3x sentinels */
- expected_events = ARRAY_SIZE(core_events) +
- ARRAY_SIZE(uncore_events) +
- ARRAY_SIZE(sys_events) - 3;
+ if (!pe->name)
+ return 0;

- if (!table || !sys_event_tables)
- return -1;
+ if (pe->pmu)
+ test_event_table = &uncore_events[0];
+ else
+ test_event_table = &core_events[0];

- for (; table->name; table++) {
- struct perf_pmu_test_event const **test_event_table;
- bool found = false;
+ for (; *test_event_table; test_event_table++) {
+ struct perf_pmu_test_event const *test_event = *test_event_table;
+ struct pmu_event const *event = &test_event->event;

- if (table->pmu)
- test_event_table = &uncore_events[0];
- else
- test_event_table = &core_events[0];
+ if (strcmp(pe->name, event->name))
+ continue;
+ found = true;
+ (*map_events)++;

- for (; *test_event_table; test_event_table++) {
- struct perf_pmu_test_event const *test_event = *test_event_table;
- struct pmu_event const *event = &test_event->event;
+ if (compare_pmu_events(pe, event))
+ return -1;

- if (strcmp(table->name, event->name))
- continue;
- found = true;
- map_events++;
+ pr_debug("testing event table %s: pass\n", pe->name);
+ }
+ if (!found) {
+ pr_err("testing event table: could not find event %s\n", pe->name);
+ return -1;
+ }
+ return 0;
+}

- if (compare_pmu_events(table, event))
- return -1;
+static int test__pmu_event_table_sys_callback(const struct pmu_event *pe,
+ const struct pmu_event *table __maybe_unused,
+ void *data)
+{
+ int *map_events = data;
+ struct perf_pmu_test_event const **test_event_table;
+ bool found = false;

- pr_debug("testing event table %s: pass\n", table->name);
- }
+ test_event_table = &sys_events[0];

- if (!found) {
- pr_err("testing event table: could not find event %s\n",
- table->name);
- return -1;
- }
- }
+ for (; *test_event_table; test_event_table++) {
+ struct perf_pmu_test_event const *test_event = *test_event_table;
+ struct pmu_event const *event = &test_event->event;

- for (table = sys_event_tables; table->name; table++) {
- struct perf_pmu_test_event const **test_event_table;
- bool found = false;
+ if (strcmp(pe->name, event->name))
+ continue;
+ found = true;
+ (*map_events)++;

- test_event_table = &sys_events[0];
+ if (compare_pmu_events(pe, event))
+ return TEST_FAIL;

- for (; *test_event_table; test_event_table++) {
- struct perf_pmu_test_event const *test_event = *test_event_table;
- struct pmu_event const *event = &test_event->event;
+ pr_debug("testing sys event table %s: pass\n", pe->name);
+ }
+ if (!found) {
+ pr_debug("testing sys event table: could not find event %s\n", pe->name);
+ return TEST_FAIL;
+ }
+ return TEST_OK;
+}

- if (strcmp(table->name, event->name))
- continue;
- found = true;
- map_events++;
+/* Verify generated events from pmu-events.c are as expected */
+static int test__pmu_event_table(struct test_suite *test __maybe_unused,
+ int subtest __maybe_unused)
+{
+ const struct pmu_event *sys_event_table = find_sys_events_table("pme_test_soc_sys");
+ const struct pmu_event *table = find_core_events_table("testarch", "testcpu");
+ int map_events = 0, expected_events, err;

- if (compare_pmu_events(table, event))
- return -1;
+ /* ignore 3x sentinels */
+ expected_events = ARRAY_SIZE(core_events) +
+ ARRAY_SIZE(uncore_events) +
+ ARRAY_SIZE(sys_events) - 3;

- pr_debug("testing sys event table %s: pass\n", table->name);
- }
- if (!found) {
- pr_debug("testing event table: could not find event %s\n",
- table->name);
- return -1;
- }
- }
+ if (!table || !sys_event_table)
+ return -1;
+
+ err = pmu_events_table_for_each_event(table, test__pmu_event_table_core_callback,
+ &map_events);
+ if (err)
+ return err;
+
+ err = pmu_events_table_for_each_event(sys_event_table, test__pmu_event_table_sys_callback,
+ &map_events);
+ if (err)
+ return err;

if (map_events != expected_events) {
pr_err("testing event table: found %d, but expected %d\n",
map_events, expected_events);
- return -1;
+ return TEST_FAIL;
}

return 0;
diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
index 8d994539d6ea..cae97b6dc5bc 100644
--- a/tools/perf/util/metricgroup.c
+++ b/tools/perf/util/metricgroup.c
@@ -538,12 +538,40 @@ static int metricgroup__print_sys_event_iter(const struct pmu_event *pe,
d->details, d->groups, d->metriclist);
}

+struct metricgroup_print_data {
+ const char *pmu_name;
+ struct strlist *metriclist;
+ char *filter;
+ struct rblist *groups;
+ bool metricgroups;
+ bool raw;
+ bool details;
+};
+
+static int metricgroup__print_callback(const struct pmu_event *pe,
+ const struct pmu_event *table __maybe_unused,
+ void *vdata)
+{
+ struct metricgroup_print_data *data = vdata;
+
+ if (!pe->metric_expr)
+ return 0;
+
+ if (data->pmu_name && perf_pmu__is_hybrid(pe->pmu) && strcmp(data->pmu_name, pe->pmu))
+ return 0;
+
+ return metricgroup__print_pmu_event(pe, data->metricgroups, data->filter,
+ data->raw, data->details, data->groups,
+ data->metriclist);
+}
+
void metricgroup__print(bool metrics, bool metricgroups, char *filter,
bool raw, bool details, const char *pmu_name)
{
struct rblist groups;
struct rb_node *node, *next;
struct strlist *metriclist = NULL;
+ const struct pmu_event *table;

if (!metricgroups) {
metriclist = strlist__new(NULL, NULL);
@@ -555,22 +583,22 @@ void metricgroup__print(bool metrics, bool metricgroups, char *filter,
groups.node_new = mep_new;
groups.node_cmp = mep_cmp;
groups.node_delete = mep_delete;
- for (const struct pmu_event *pe = pmu_events_table__find(); pe; pe++) {
+ table = pmu_events_table__find();
+ if (table) {
+ struct metricgroup_print_data data = {
+ .pmu_name = pmu_name,
+ .metriclist = metriclist,
+ .metricgroups = metricgroups,
+ .filter = filter,
+ .raw = raw,
+ .details = details,
+ .groups = &groups,
+ };

- if (!pe->name && !pe->metric_group && !pe->metric_name)
- break;
- if (!pe->metric_expr)
- continue;
- if (pmu_name && perf_pmu__is_hybrid(pe->pmu) &&
- strcmp(pmu_name, pe->pmu)) {
- continue;
- }
- if (metricgroup__print_pmu_event(pe, metricgroups, filter,
- raw, details, &groups,
- metriclist) < 0)
- return;
+ pmu_events_table_for_each_event(table,
+ metricgroup__print_callback,
+ &data);
}
-
{
struct metricgroup_iter_data data = {
.fn = metricgroup__print_sys_event_iter,
@@ -1043,30 +1071,35 @@ static int __add_metric(struct list_head *metric_list,
return ret;
}

-#define table_for_each_event(__pe, __idx, __table) \
- if (__table) \
- for (__idx = 0, __pe = &__table[__idx]; \
- __pe->name || __pe->metric_group || __pe->metric_name; \
- __pe = &__table[++__idx])
+struct metricgroup__find_metric_data {
+ const char *metric;
+ const struct pmu_event *pe;
+};
+
+static int metricgroup__find_metric_callback(const struct pmu_event *pe,
+ const struct pmu_event *table __maybe_unused,
+ void *vdata)
+{
+ struct metricgroup__find_metric_data *data = vdata;
+
+ if (!match_metric(pe->metric_name, data->metric))
+ return 0;

-#define table_for_each_metric(__pe, __idx, __table, __metric) \
- table_for_each_event(__pe, __idx, __table) \
- if (__pe->metric_expr && \
- (match_metric(__pe->metric_group, __metric) || \
- match_metric(__pe->metric_name, __metric)))
+ data->pe = pe;
+ return -1;
+}

const struct pmu_event *metricgroup__find_metric(const char *metric,
const struct pmu_event *table)
{
- const struct pmu_event *pe;
- int i;
+ struct metricgroup__find_metric_data data = {
+ .metric = metric,
+ .pe = NULL,
+ };

- table_for_each_event(pe, i, table) {
- if (match_metric(pe->metric_name, metric))
- return pe;
- }
+ pmu_events_table_for_each_event(table, metricgroup__find_metric_callback, &data);

- return NULL;
+ return data.pe;
}

static int add_metric(struct list_head *metric_list,
@@ -1151,6 +1184,33 @@ static int metric_list_cmp(void *priv __maybe_unused, const struct list_head *l,
return right_count - left_count;
}

+struct metricgroup__add_metric_data {
+ struct list_head *list;
+ const char *metric_name;
+ const char *modifier;
+ bool metric_no_group;
+ bool has_match;
+};
+
+static int metricgroup__add_metric_callback(const struct pmu_event *pe,
+ const struct pmu_event *table,
+ void *vdata)
+{
+ struct metricgroup__add_metric_data *data = vdata;
+ int ret = 0;
+
+ if (pe->metric_expr &&
+ (match_metric(pe->metric_group, data->metric_name) ||
+ match_metric(pe->metric_name, data->metric_name))) {
+
+ data->has_match = true;
+ ret = add_metric(data->list, pe, data->modifier, data->metric_no_group,
+ /*root_metric=*/NULL,
+ /*visited_metrics=*/NULL, table);
+ }
+ return ret;
+}
+
/**
* metricgroup__add_metric - Find and add a metric, or a metric group.
* @metric_name: The name of the metric or metric group. For example, "IPC"
@@ -1169,24 +1229,29 @@ static int metricgroup__add_metric(const char *metric_name, const char *modifier
struct list_head *metric_list,
const struct pmu_event *table)
{
- const struct pmu_event *pe;
LIST_HEAD(list);
- int i, ret;
+ int ret;
bool has_match = false;

- /*
- * Iterate over all metrics seeing if metric matches either the name or
- * group. When it does add the metric to the list.
- */
- table_for_each_metric(pe, i, table, metric_name) {
- has_match = true;
- ret = add_metric(&list, pe, modifier, metric_no_group,
- /*root_metric=*/NULL,
- /*visited_metrics=*/NULL, table);
+ {
+ struct metricgroup__add_metric_data data = {
+ .list = &list,
+ .metric_name = metric_name,
+ .modifier = modifier,
+ .metric_no_group = metric_no_group,
+ .has_match = false,
+ };
+ /*
+ * Iterate over all metrics seeing if metric matches either the
+ * name or group. When it does add the metric to the list.
+ */
+ ret = pmu_events_table_for_each_event(table, metricgroup__add_metric_callback,
+ &data);
if (ret)
goto out;
- }

+ has_match = data.has_match;
+ }
{
struct metricgroup_iter_data data = {
.fn = metricgroup__add_metric_sys_event_iter,
@@ -1602,26 +1667,30 @@ int metricgroup__parse_groups_test(struct evlist *evlist,
metric_no_merge, &perf_pmu__fake, metric_events, table);
}

+static int metricgroup__has_metric_callback(const struct pmu_event *pe,
+ const struct pmu_event *table __maybe_unused,
+ void *vdata)
+{
+ const char *metric = vdata;
+
+ if (!pe->metric_expr)
+ return 0;
+
+ if (match_metric(pe->metric_name, metric))
+ return 1;
+
+ return 0;
+}
+
bool metricgroup__has_metric(const char *metric)
{
const struct pmu_event *table = pmu_events_table__find();
- const struct pmu_event *pe;
- int i;

if (!table)
return false;

- for (i = 0; ; i++) {
- pe = &table[i];
-
- if (!pe->name && !pe->metric_group && !pe->metric_name)
- break;
- if (!pe->metric_expr)
- continue;
- if (match_metric(pe->metric_name, metric))
- return true;
- }
- return false;
+ return pmu_events_table_for_each_event(table, metricgroup__has_metric_callback,
+ (void *)metric) ? true : false;
}

int metricgroup__copy_metric_events(struct evlist *evlist, struct cgroup *cgrp,
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index f117324eb5f0..dd1e171d7480 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -791,6 +791,36 @@ bool pmu_uncore_alias_match(const char *pmu_name, const char *name)
return res;
}

+struct pmu_add_cpu_aliases_map_data {
+ struct list_head *head;
+ const char *name;
+ const char *cpu_name;
+ struct perf_pmu *pmu;
+};
+
+static int pmu_add_cpu_aliases_map_callback(const struct pmu_event *pe,
+ const struct pmu_event *table __maybe_unused,
+ void *vdata)
+{
+ struct pmu_add_cpu_aliases_map_data *data = vdata;
+ const char *pname = pe->pmu ? pe->pmu : data->cpu_name;
+
+ if (!pe->name)
+ return 0;
+
+ if (data->pmu->is_uncore && pmu_uncore_alias_match(pname, data->name))
+ goto new_alias;
+
+ if (strcmp(pname, data->name))
+ return 0;
+
+new_alias:
+ /* need type casts to override 'const' */
+ __perf_pmu__new_alias(data->head, NULL, (char *)pe->name, (char *)pe->desc,
+ (char *)pe->event, pe);
+ return 0;
+}
+
/*
* From the pmu_events_map, find the table of PMU events that corresponds
* to the current running CPU. Then, add all PMU events from that table
@@ -799,35 +829,14 @@ bool pmu_uncore_alias_match(const char *pmu_name, const char *name)
void pmu_add_cpu_aliases_table(struct list_head *head, struct perf_pmu *pmu,
const struct pmu_event *table)
{
- int i;
- const char *name = pmu->name;
- /*
- * Found a matching PMU events table. Create aliases
- */
- i = 0;
- while (1) {
- const char *cpu_name = is_arm_pmu_core(name) ? name : "cpu";
- const struct pmu_event *pe = &table[i++];
- const char *pname = pe->pmu ? pe->pmu : cpu_name;
-
- if (!pe->name) {
- if (pe->metric_group || pe->metric_name)
- continue;
- break;
- }
-
- if (pmu->is_uncore && pmu_uncore_alias_match(pname, name))
- goto new_alias;
-
- if (strcmp(pname, name))
- continue;
+ struct pmu_add_cpu_aliases_map_data data = {
+ .head = head,
+ .name = pmu->name,
+ .cpu_name = is_arm_pmu_core(pmu->name) ? pmu->name : "cpu",
+ .pmu = pmu,
+ };

-new_alias:
- /* need type casts to override 'const' */
- __perf_pmu__new_alias(head, NULL, (char *)pe->name,
- (char *)pe->desc, (char *)pe->event,
- pe);
- }
+ pmu_events_table_for_each_event(table, pmu_add_cpu_aliases_map_callback, &data);
}

static void pmu_add_cpu_aliases(struct list_head *head, struct perf_pmu *pmu)
diff --git a/tools/perf/util/s390-sample-raw.c b/tools/perf/util/s390-sample-raw.c
index dddd2be59827..235319d45d02 100644
--- a/tools/perf/util/s390-sample-raw.c
+++ b/tools/perf/util/s390-sample-raw.c
@@ -129,6 +129,28 @@ static int get_counterset_start(int setnr)
}
}

+struct get_counter_name_data {
+ int wanted;
+ const char *result;
+};
+
+static int get_counter_name_callback(const struct pmu_event *evp,
+ const struct pmu_event *table __maybe_unused,
+ void *vdata)
+{
+ struct get_counter_name_data *data = vdata;
+ int rc, event_nr;
+
+ if (evp->name == NULL || evp->event == NULL)
+ return 0;
+ rc = sscanf(evp->event, "event=%x", &event_nr);
+ if (rc == 1 && event_nr == data->wanted) {
+ data->result = evp->name;
+ return 1; /* Terminate the search. */
+ }
+ return 0;
+}
+
/* Scan the PMU table and extract the logical name of a counter from the
* PMU events table. Input is the counter set and counter number with in the
* set. Construct the event number and use this as key. If they match return
@@ -137,20 +159,16 @@ static int get_counterset_start(int setnr)
*/
static const char *get_counter_name(int set, int nr, const struct pmu_event *table)
{
- int rc, event_nr, wanted = get_counterset_start(set) + nr;
+ struct get_counter_name_data data = {
+ .wanted = get_counterset_start(set) + nr,
+ .result = NULL,
+ };

- if (table) {
- const struct pmu_event *evp = table;
+ if (!table)
+ return NULL;

- for (; evp->name || evp->event || evp->desc; ++evp) {
- if (evp->name == NULL || evp->event == NULL)
- continue;
- rc = sscanf(evp->event, "event=%x", &event_nr);
- if (rc == 1 && event_nr == wanted)
- return evp->name;
- }
- }
- return NULL;
+ pmu_events_table_for_each_event(table, get_counter_name_callback, &data);
+ return data.result;
}

static void s390_cpumcfdg_dump(struct perf_sample *sample)
--
2.37.1.595.g718a3a8f04-goog