diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 04a3556..0be7795 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -157,11 +157,10 @@
 	int nmissed;
 	size_t data_size;
 	struct hlist_head free_instances;
-	struct hlist_head used_instances;
+	spinlock_t lock;
 };
 
 struct kretprobe_instance {
-	struct hlist_node uflist; /* either on free list or used list */
 	struct hlist_node hlist;
 	struct kretprobe *rp;
 	kprobe_opcode_t *ret_addr;
@@ -201,7 +200,6 @@
 }
 #endif /* CONFIG_KPROBES_SANITY_TEST */
 
-extern spinlock_t kretprobe_lock;
 extern struct mutex kprobe_mutex;
 extern int arch_prepare_kprobe(struct kprobe *p);
 extern void arch_arm_kprobe(struct kprobe *p);
@@ -214,6 +212,9 @@
 
 /* Get the kprobe at this addr (if any) - called with preemption disabled */
 struct kprobe *get_kprobe(void *addr);
+void kretprobe_hash_lock(struct task_struct *tsk,
+			 struct hlist_head **head, unsigned long *flags);
+void kretprobe_hash_unlock(struct task_struct *tsk, unsigned long *flags);
 struct hlist_head * kretprobe_inst_table_head(struct task_struct *tsk);
 
 /* kprobe_running() will just return the current_kprobe on this CPU */