[RFC PATCH v2 3/9] perf pmus: Expose duplicate uncore PMU scanning helpers

[Ian Rogers <irogers@google.com>]

Export perf_pmus__scan_skip_duplicates() and add
perf_pmu__num_duplicates() to count numbered uncore PMU instances
sharing a common prefix.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/util/pmus.c | 23 ++++++++++++++++++++++-
 tools/perf/util/pmus.h |  2 ++
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/pmus.c b/tools/perf/util/pmus.c
index ea727d577c89..8657b36767ff 100644
--- a/tools/perf/util/pmus.c
+++ b/tools/perf/util/pmus.c
@@ -455,7 +455,7 @@ struct perf_pmu *perf_pmus__scan_matching_wildcard(struct perf_pmu *pmu, const c
 	return NULL;
 }
 
-static struct perf_pmu *perf_pmus__scan_skip_duplicates(struct perf_pmu *pmu)
+struct perf_pmu *perf_pmus__scan_skip_duplicates(struct perf_pmu *pmu)
 {
 	bool use_core_pmus = !pmu || pmu->is_core;
 	int last_pmu_name_len = 0;
@@ -492,6 +492,27 @@ static struct perf_pmu *perf_pmus__scan_skip_duplicates(struct perf_pmu *pmu)
 	return NULL;
 }
 
+size_t perf_pmu__num_duplicates(const struct perf_pmu *pmu)
+{
+	const struct perf_pmu *pos = pmu;
+	size_t base_len;
+	size_t count = 1;
+
+	if (!pmu || pmu->is_core)
+		return 1;
+
+	base_len = pmu_name_len_no_suffix(pmu->name ?: "");
+	list_for_each_entry_continue(pos, &other_pmus, list) {
+		size_t pos_len = pmu_name_len_no_suffix(pos->name ?: "");
+
+		if (pos_len != base_len ||
+		    strncmp(pmu->name ?: "", pos->name ?: "", base_len))
+			break;
+		count++;
+	}
+	return count;
+}
+
 struct perf_pmu *perf_pmus__scan_for_uncore_id(struct perf_pmu *pmu, const char *compat)
 {
 	if (!pmu) {
diff --git a/tools/perf/util/pmus.h b/tools/perf/util/pmus.h
index d1646f91036e..58ecab3e3da3 100644
--- a/tools/perf/util/pmus.h
+++ b/tools/perf/util/pmus.h
@@ -23,6 +23,8 @@ struct perf_pmu *perf_pmus__find_by_attr(const struct perf_event_attr *attr);
 
 struct perf_pmu *perf_pmus__scan(struct perf_pmu *pmu);
 struct perf_pmu *perf_pmus__scan_core(struct perf_pmu *pmu);
+struct perf_pmu *perf_pmus__scan_skip_duplicates(struct perf_pmu *pmu);
+size_t perf_pmu__num_duplicates(const struct perf_pmu *pmu);
 struct perf_pmu *perf_pmus__scan_for_event(struct perf_pmu *pmu, const char *event);
 struct perf_pmu *perf_pmus__scan_matching_wildcard(struct perf_pmu *pmu, const char *wildcard);
 struct perf_pmu *perf_pmus__scan_for_uncore_id(struct perf_pmu *pmu, const char *compat);
-- 
2.56.0.212.g129ede20d9-goog