1 files changed, 61 insertions, 0 deletions
diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
index 6e2a7198b382..ad562743d769 100644
--- a/tools/perf/util/dso.c
+++ b/tools/perf/util/dso.c
@@ -1269,6 +1269,67 @@ static void dso__set_long_name_id(struct dso *dso, const char *name, struct dso_
 		__dsos__findnew_link_by_longname_id(root, dso, NULL, id);
 }
 
+static int __dso_id__cmp(struct dso_id *a, struct dso_id *b)
+{
+	if (a->maj > b->maj) return -1;
+	if (a->maj < b->maj) return 1;
+
+	if (a->min > b->min) return -1;
+	if (a->min < b->min) return 1;
+
+	if (a->ino > b->ino) return -1;
+	if (a->ino < b->ino) return 1;
+
+	/*
+	 * Synthesized MMAP events have zero ino_generation, avoid comparing
+	 * them with MMAP events with actual ino_generation.
+	 *
+	 * I found it harmful because the mismatch resulted in a new
+	 * dso that did not have a build ID whereas the original dso did have a
+	 * build ID. The build ID was essential because the object was not found
+	 * otherwise. - Adrian
+	 */
+	if (a->ino_generation && b->ino_generation) {
+		if (a->ino_generation > b->ino_generation) return -1;
+		if (a->ino_generation < b->ino_generation) return 1;
+	}
+
+	return 0;
+}
+
+bool dso_id__empty(struct dso_id *id)
+{
+	if (!id)
+		return true;
+
+	return !id->maj && !id->min && !id->ino && !id->ino_generation;
+}
+
+void dso__inject_id(struct dso *dso, struct dso_id *id)
+{
+	dso->id.maj = id->maj;
+	dso->id.min = id->min;
+	dso->id.ino = id->ino;
+	dso->id.ino_generation = id->ino_generation;
+}
+
+int dso_id__cmp(struct dso_id *a, struct dso_id *b)
+{
+	/*
+	 * The second is always dso->id, so zeroes if not set, assume passing
+	 * NULL for a means a zeroed id
+	 */
+	if (dso_id__empty(a) || dso_id__empty(b))
+		return 0;
+
+	return __dso_id__cmp(a, b);
+}
+
+int dso__cmp_id(struct dso *a, struct dso *b)
+{
+	return __dso_id__cmp(&a->id, &b->id);
+}
+
 void dso__set_long_name(struct dso *dso, const char *name, bool name_allocated)
 {
 	dso__set_long_name_id(dso, name, NULL, name_allocated);