[PATCH v4 1/7] module: Add lock_modules() and unlock_modules()

[Jarkko Sakkinen]

Add wrapper functions for acquiring module_mutex so that the locking can
be implicitly compiled out when CONFIG_MODULES is not enabled.

Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Suggested-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
---
 include/linux/module.h | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/include/linux/module.h b/include/linux/module.h
index 2e6670860d27..8850b9692b8f 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -705,6 +705,16 @@ static inline bool is_livepatch_module(struct module *mod)
 bool is_module_sig_enforced(void);
 void set_module_sig_enforced(void);
 
+static inline void lock_modules(void)
+{
+	mutex_lock(&module_mutex);
+}
+
+static inline void unlock_modules(void)
+{
+	mutex_unlock(&module_mutex);
+}
+
 #else /* !CONFIG_MODULES... */
 
 static inline struct module *__module_address(unsigned long addr)
@@ -852,6 +862,14 @@ void *dereference_module_function_descriptor(struct module *mod, void *ptr)
 	return ptr;
 }
 
+static inline void lock_modules(void)
+{
+}
+
+static inline void unlock_modules(void)
+{
+}
+
 #endif /* CONFIG_MODULES */
 
 #ifdef CONFIG_SYSFS
-- 
2.25.1