diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
index 9f4b72d8f50f..b8b5fdb1a15b 100644
--- a/tools/perf/util/dso.c
+++ b/tools/perf/util/dso.c
@@ -202,7 +202,7 @@ static const struct {
 	{ NULL, NULL },
 };
 
-bool is_supported_compression(const char *ext)
+static bool is_supported_compression(const char *ext)
 {
 	unsigned i;
 
diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
index e1adadd1fe1e..870346b333ee 100644
--- a/tools/perf/util/dso.h
+++ b/tools/perf/util/dso.h
@@ -250,7 +250,6 @@ int dso__kernel_module_get_build_id(struct dso *dso, const char *root_dir);
 char dso__symtab_origin(const struct dso *dso);
 int dso__read_binary_type_filename(const struct dso *dso, enum dso_binary_type type,
 				   char *root_dir, char *filename, size_t size);
-bool is_supported_compression(const char *ext);
 bool is_kernel_module(const char *pathname, int cpumode);
 bool dso__needs_decompress(struct dso *dso);
 int dso__decompress_kmodule_fd(struct dso *dso, const char *name);