diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 24de5f1..ace31fb 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -941,10 +941,8 @@
 }
 
 extern struct perf_guest_info_callbacks *perf_guest_cbs;
-extern int perf_register_guest_info_callbacks(
-		struct perf_guest_info_callbacks *);
-extern int perf_unregister_guest_info_callbacks(
-		struct perf_guest_info_callbacks *);
+extern int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
+extern int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
 
 extern void perf_event_comm(struct task_struct *tsk);
 extern void perf_event_fork(struct task_struct *tsk);
@@ -1016,9 +1014,9 @@
 perf_bp_event(struct perf_event *event, void *data)			{ }
 
 static inline int perf_register_guest_info_callbacks
-(struct perf_guest_info_callbacks *) {return 0; }
+(struct perf_guest_info_callbacks *callbacks) { return 0; }
 static inline int perf_unregister_guest_info_callbacks
-(struct perf_guest_info_callbacks *) {return 0; }
+(struct perf_guest_info_callbacks *callbacks) { return 0; }
 
 static inline void perf_event_mmap(struct vm_area_struct *vma)		{ }
 static inline void perf_event_comm(struct task_struct *tsk)		{ }