1 files changed, 19 insertions, 2 deletions

diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index cd15df6c63cd..5e781d824e6d 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -301,6 +301,8 @@ static inline int unregister_pm_notifier(struct notifier_block *nb)
 #define pm_notifier(fn, pri)    do { (void)(fn); } while (0)
 #endif /* !CONFIG_PM_SLEEP */
 
+extern struct mutex pm_mutex;
+
 #ifndef CONFIG_HIBERNATION
 static inline void register_nosave_region(unsigned long b, unsigned long e)
 {
@@ -308,8 +310,23 @@ static inline void register_nosave_region(unsigned long b, unsigned long e)
 static inline void register_nosave_region_late(unsigned long b, unsigned long e)
 {
 }
-#endif
 
-extern struct mutex pm_mutex;
+static inline void lock_system_sleep(void) {}
+static inline void unlock_system_sleep(void) {}
+
+#else
+
+/* Let some subsystems like memory hotadd exclude hibernation */
+
+static inline void lock_system_sleep(void)
+{
+        mutex_lock(&pm_mutex);
+}
+
+static inline void unlock_system_sleep(void)
+{
+        mutex_unlock(&pm_mutex);
+}
+#endif
 
 #endif /* _LINUX_SUSPEND_H */