extern int perf_default_config(const char *, const char *, void *);
extern int perf_config(config_fn_t fn, void *);
extern int perf_config_int(const char *, const char *);
+extern u64 perf_config_u64(const char *, const char *);
extern int perf_config_bool(const char *, const char *);
extern int config_error_nonbool(const char *);
extern const char *perf_config_dirname(const char *, const char *);