[PATCH v1 6/9] perf parse-events: Legacy cache names on all PMUs and lower priority

Ian Rogers
2024-04-15T06:36:59Z

Prior behavior is to not look for legacy cache names in sysfs/json and
to create events on all core PMUs. New behavior is to look for
sysfs/json events first on all PMUs, for core PMUs add a legacy event
if the sysfs/json event isn't present.

This is done so that there is consistency with how event names in
terms are handled and their prioritization of sysfs/json over
legacy. It may make sense to use a legacy cache event name as an event
name on a non-core PMU so we should allow it.

Signed-off-by: Ian Rogers <irogers@google.com>
---
tools/perf/util/parse-events.c | 38 +++++++++++++++++++++++++++-------
tools/perf/util/parse-events.h | 2 +-
2 files changed, 31 insertions(+), 9 deletions(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index f4de374dab59..f711ad9b18f0 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -442,17 +442,21 @@ bool parse_events__filter_pmu(const struct parse_events_state *parse_state,
return strcmp(parse_state->pmu_filter, pmu->name) != 0;
}

+static int parse_events_add_pmu(struct parse_events_state *parse_state,
+ struct list_head *list, struct perf_pmu *pmu,
+ const struct parse_events_terms *const_parsed_terms,
+ bool auto_merge_stats);
+
int parse_events_add_cache(struct list_head *list, int *idx, const char *name,
struct parse_events_state *parse_state,
- struct parse_events_terms *head_config)
+ struct parse_events_terms *parsed_terms)
{
struct perf_pmu *pmu = NULL;
bool found_supported = false;
- const char *config_name = get_config_name(head_config);
- const char *metric_id = get_config_metric_id(head_config);
+ const char *config_name = get_config_name(parsed_terms);
+ const char *metric_id = get_config_metric_id(parsed_terms);

- /* Legacy cache events are only supported by core PMUs. */
- while ((pmu = perf_pmus__scan_core(pmu)) != NULL) {
+ while ((pmu = perf_pmus__scan(pmu)) != NULL) {
LIST_HEAD(config_terms);
struct perf_event_attr attr;
int ret;
@@ -460,6 +464,24 @@ int parse_events_add_cache(struct list_head *list, int *idx, const char *name,
if (parse_events__filter_pmu(parse_state, pmu))
continue;

+ if (perf_pmu__have_event(pmu, name)) {
+ /*
+ * The PMU has the event so add as not a legacy cache
+ * event.
+ */
+ ret = parse_events_add_pmu(parse_state, list, pmu,
+ parsed_terms,
+ perf_pmu__auto_merge_stats(pmu));
+ if (ret)
+ return ret;
+ continue;
+ }
+
+ if (!pmu->is_core) {
+ /* Legacy cache events are only supported by core PMUs. */
+ continue;
+ }
+
memset(&attr, 0, sizeof(attr));
attr.type = PERF_TYPE_HW_CACHE;

@@ -469,11 +491,11 @@ int parse_events_add_cache(struct list_head *list, int *idx, const char *name,

found_supported = true;

- if (head_config) {
- if (config_attr(&attr, head_config, parse_state->error, config_term_common))
+ if (parsed_terms) {
+ if (config_attr(&attr, parsed_terms, parse_state->error, config_term_common))
return -EINVAL;

- if (get_config_terms(head_config, &config_terms))
+ if (get_config_terms(parsed_terms, &config_terms))
return -ENOMEM;
}

diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index a331b9f0da2b..db47913e54bc 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -203,7 +203,7 @@ int parse_events_add_tool(struct parse_events_state *parse_state,
int tool_event);
int parse_events_add_cache(struct list_head *list, int *idx, const char *name,
struct parse_events_state *parse_state,
- struct parse_events_terms *head_config);
+ struct parse_events_terms *parsed_terms);
int parse_events__decode_legacy_cache(const char *name, int pmu_type, __u64 *config);
int parse_events_add_breakpoint(struct parse_events_state *parse_state,
struct list_head *list,