tracepoint: Support iterating over tracepoints on modules

Add for_each_module_tracepoint() for iterating over tracepoints
on modules. This is similar to the for_each_kernel_tracepoint()
but only for the tracepoints on modules (not including kernel
built-in tracepoints).

Link: https://lore.kernel.org/all/172397777800.286558.14554748203446214056.stgit@devnote2/

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

include/linux/tracepoint.h

@@ -64,6 +64,8 @@ struct tp_module {
 bool trace_module_has_bad_taint(struct module *mod);
 extern int register_tracepoint_module_notifier(struct notifier_block *nb);
 extern int unregister_tracepoint_module_notifier(struct notifier_block *nb);
+void for_each_module_tracepoint(void (*fct)(struct tracepoint *, void *),
+				void *priv);
 #else
 static inline bool trace_module_has_bad_taint(struct module *mod)
 {
@@ -79,6 +81,11 @@ int unregister_tracepoint_module_notifier(struct notifier_block *nb)
 {
 	return 0;
 }
+static inline
+void for_each_module_tracepoint(void (*fct)(struct tracepoint *, void *),
+				void *priv)
+{
+}
 #endif /* CONFIG_MODULES */
 
 /*