diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index 581abf84856691ad2e5ce39f77f9c9112170061c..d63bb77dab35a4ecf56fd33e9d9ad21d93ab2876 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -160,7 +160,7 @@ void do_trace_rcu_torture_read(const char *rcutorturename,
  * more than one CPU).
  */
 void call_rcu(struct rcu_head *head,
-	      void (*func)(struct rcu_head *head));
+	      rcu_callback_t func);
 
 #else /* #ifdef CONFIG_PREEMPT_RCU */
 
@@ -191,7 +191,7 @@ void call_rcu(struct rcu_head *head,
  * memory ordering guarantees.
  */
 void call_rcu_bh(struct rcu_head *head,
-		 void (*func)(struct rcu_head *head));
+		 rcu_callback_t func);
 
 /**
  * call_rcu_sched() - Queue an RCU for invocation after sched grace period.
@@ -213,7 +213,7 @@ void call_rcu_bh(struct rcu_head *head,
  * memory ordering guarantees.
  */
 void call_rcu_sched(struct rcu_head *head,
-		    void (*func)(struct rcu_head *rcu));
+		    rcu_callback_t func);
 
 void synchronize_sched(void);
 
@@ -274,7 +274,7 @@ do {									\
  * See the description of call_rcu() for more detailed information on
  * memory ordering guarantees.
  */
-void call_rcu_tasks(struct rcu_head *head, void (*func)(struct rcu_head *head));
+void call_rcu_tasks(struct rcu_head *head, rcu_callback_t func);
 void synchronize_rcu_tasks(void);
 void rcu_barrier_tasks(void);
 
@@ -1065,7 +1065,7 @@ static inline notrace void rcu_read_unlock_sched_notrace(void)
 #define __kfree_rcu(head, offset) \
 	do { \
 		BUILD_BUG_ON(!__is_kfree_rcu_offset(offset)); \
-		kfree_call_rcu(head, (void (*)(struct rcu_head *))(unsigned long)(offset)); \
+		kfree_call_rcu(head, (rcu_callback_t)(unsigned long)(offset)); \
 	} while (0)
 
 /**
diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h
index ff968b7af3a4b61c9496f5222a7f600a42f5eca6..c8a0722f77ea07ea74823dca6ab725273a27918e 100644
--- a/include/linux/rcutiny.h
+++ b/include/linux/rcutiny.h
@@ -83,7 +83,7 @@ static inline void synchronize_sched_expedited(void)
 }
 
 static inline void kfree_call_rcu(struct rcu_head *head,
-				  void (*func)(struct rcu_head *rcu))
+				  rcu_callback_t func)
 {
 	call_rcu(head, func);
 }
diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h
index 5abec82f325ecf5e2a0c06c21d566f94f5559721..60d15a080d7c3dcde45cf458df5632dfc5b36ac2 100644
--- a/include/linux/rcutree.h
+++ b/include/linux/rcutree.h
@@ -48,7 +48,7 @@ void synchronize_rcu_bh(void);
 void synchronize_sched_expedited(void);
 void synchronize_rcu_expedited(void);
 
-void kfree_call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu));
+void kfree_call_rcu(struct rcu_head *head, rcu_callback_t func);
 
 /**
  * synchronize_rcu_bh_expedited - Brute-force RCU-bh grace period
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 77192953dee5f5a54b10131ee70684fafb18c2c6..51c8e7f02f48b65955b94118d42610515eb3126d 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -448,7 +448,7 @@ static void synchronize_rcu_busted(void)
 }
 
 static void
-call_rcu_busted(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+call_rcu_busted(struct rcu_head *head, rcu_callback_t func)
 {
 	/* This is a deliberate bug for testing purposes only! */
 	func(head);
@@ -523,7 +523,7 @@ static void srcu_torture_synchronize(void)
 }
 
 static void srcu_torture_call(struct rcu_head *head,
-			      void (*func)(struct rcu_head *head))
+			      rcu_callback_t func)
 {
 	call_srcu(srcu_ctlp, head, func);
 }
diff --git a/kernel/rcu/srcu.c b/kernel/rcu/srcu.c
index d3fcb2ec8536724615cbdd5ce5a891cbcc020934..9e6122540d28429a2f1902c13b5e92ade124a624 100644
--- a/kernel/rcu/srcu.c
+++ b/kernel/rcu/srcu.c
@@ -387,7 +387,7 @@ static void srcu_flip(struct srcu_struct *sp)
  * srcu_struct structure.
  */
 void call_srcu(struct srcu_struct *sp, struct rcu_head *head,
-		void (*func)(struct rcu_head *head))
+	       rcu_callback_t func)
 {
 	unsigned long flags;
 
diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c
index d0471056d0afac18ed1739981aaa415495414791..944b1b491ed84b3d2d1cf977a9838a30cf405121 100644
--- a/kernel/rcu/tiny.c
+++ b/kernel/rcu/tiny.c
@@ -44,7 +44,7 @@ struct rcu_ctrlblk;
 static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp);
 static void rcu_process_callbacks(struct softirq_action *unused);
 static void __call_rcu(struct rcu_head *head,
-		       void (*func)(struct rcu_head *rcu),
+		       rcu_callback_t func,
 		       struct rcu_ctrlblk *rcp);
 
 #include "tiny_plugin.h"
@@ -203,7 +203,7 @@ EXPORT_SYMBOL_GPL(synchronize_sched);
  * Helper function for call_rcu() and call_rcu_bh().
  */
 static void __call_rcu(struct rcu_head *head,
-		       void (*func)(struct rcu_head *rcu),
+		       rcu_callback_t func,
 		       struct rcu_ctrlblk *rcp)
 {
 	unsigned long flags;
@@ -229,7 +229,7 @@ static void __call_rcu(struct rcu_head *head,
  * period.  But since we have but one CPU, that would be after any
  * quiescent state.
  */
-void call_rcu_sched(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+void call_rcu_sched(struct rcu_head *head, rcu_callback_t func)
 {
 	__call_rcu(head, func, &rcu_sched_ctrlblk);
 }
@@ -239,7 +239,7 @@ EXPORT_SYMBOL_GPL(call_rcu_sched);
  * Post an RCU bottom-half callback to be invoked after any subsequent
  * quiescent state.
  */
-void call_rcu_bh(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+void call_rcu_bh(struct rcu_head *head, rcu_callback_t func)
 {
 	__call_rcu(head, func, &rcu_bh_ctrlblk);
 }
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 775d36cc00506620829bd2ca14b5da21e4de79e3..b9d9e0249e2f3a7d39dacd851a629b80369a0c3d 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3017,7 +3017,7 @@ static void rcu_leak_callback(struct rcu_head *rhp)
  * is expected to specify a CPU.
  */
 static void
-__call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
+__call_rcu(struct rcu_head *head, rcu_callback_t func,
 	   struct rcu_state *rsp, int cpu, bool lazy)
 {
 	unsigned long flags;
@@ -3088,7 +3088,7 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
 /*
  * Queue an RCU-sched callback for invocation after a grace period.
  */
-void call_rcu_sched(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+void call_rcu_sched(struct rcu_head *head, rcu_callback_t func)
 {
 	__call_rcu(head, func, &rcu_sched_state, -1, 0);
 }
@@ -3097,7 +3097,7 @@ EXPORT_SYMBOL_GPL(call_rcu_sched);
 /*
  * Queue an RCU callback for invocation after a quicker grace period.
  */
-void call_rcu_bh(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+void call_rcu_bh(struct rcu_head *head, rcu_callback_t func)
 {
 	__call_rcu(head, func, &rcu_bh_state, -1, 0);
 }
@@ -3111,7 +3111,7 @@ EXPORT_SYMBOL_GPL(call_rcu_bh);
  * function may only be called from __kfree_rcu().
  */
 void kfree_call_rcu(struct rcu_head *head,
-		    void (*func)(struct rcu_head *rcu))
+		    rcu_callback_t func)
 {
 	__call_rcu(head, func, rcu_state_p, -1, 1);
 }
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index 2e991f8361e4203a85d7b8e55afc6be370d7d7be..ad11529375cce82b7184b08962d68ddd2040eee2 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -584,7 +584,7 @@ static void rcu_print_detail_task_stall(struct rcu_state *rsp);
 static int rcu_print_task_stall(struct rcu_node *rnp);
 static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp);
 static void rcu_preempt_check_callbacks(void);
-void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu));
+void call_rcu(struct rcu_head *head, rcu_callback_t func);
 static void __init __rcu_init_preempt(void);
 static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
 static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index b2bf3963a0aee328d0d3bfc0d9e997b3a5ca106f..06116ae6dfd7237ea189c3d5ec00de5acb141287 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -500,7 +500,7 @@ static void rcu_preempt_do_callbacks(void)
 /*
  * Queue a preemptible-RCU callback for invocation after a grace period.
  */
-void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+void call_rcu(struct rcu_head *head, rcu_callback_t func)
 {
 	__call_rcu(head, func, rcu_state_p, -1, 0);
 }
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index 7a0b3bc7c5ed147162bec6a600e0bfbded04257d..5f748c5a40f0756b2d6c97fa615cde551649db4a 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -534,7 +534,7 @@ static void rcu_spawn_tasks_kthread(void);
  * Post an RCU-tasks callback.  First call must be from process context
  * after the scheduler if fully operational.
  */
-void call_rcu_tasks(struct rcu_head *rhp, void (*func)(struct rcu_head *rhp))
+void call_rcu_tasks(struct rcu_head *rhp, rcu_callback_t func)
 {
 	unsigned long flags;
 	bool needwake;