patches queued for 3.1, first installment

index 4cc6a94..36e79d2 100644
@@ -1634,6 +1634,20 @@ static int rcu_cpu_kthread(void *arg)
  * to manipulate rcu_cpu_kthread_task.  There might be another CPU
  * attempting to access it during boot, but the locking in kthread_bind()
  * will enforce sufficient ordering.
+ *
+ * Please note that we cannot simply refuse to wake up the per-CPU
+ * kthread because kthreads are created in TASK_UNINTERRUPTIBLE state,
+ * which can result in softlockup complaints if the task ends up being
+ * idle for more than a couple of minutes.
+ *
+ * However, please note also that we cannot bind the per-CPU kthread to its
+ * CPU until that CPU is fully online.  We also cannot wait until the
+ * CPU is fully online before we create its per-CPU kthread, as this would
+ * deadlock the system when CPU notifiers tried waiting for grace
+ * periods.  So we bind the per-CPU kthread to its CPU only if the CPU
+ * is online.  If its CPU is not yet fully online, then the code in
+ * rcu_cpu_kthread() will wait until it is fully online, and then do
+ * the binding.
  */
 static int __cpuinit rcu_spawn_one_cpu_kthread(int cpu)
 {

@@ -1646,12 +1660,14 @@ static int __cpuinit rcu_spawn_one_cpu_kthread(int cpu)
 	t = kthread_create(rcu_cpu_kthread, (void *)(long)cpu, "rcuc%d", cpu);
 	if (IS_ERR(t))
 		return PTR_ERR(t);
-	kthread_bind(t, cpu);
+	if (cpu_online(cpu))
+		kthread_bind(t, cpu);
 	per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu;
 	WARN_ON_ONCE(per_cpu(rcu_cpu_kthread_task, cpu) != NULL);
-	per_cpu(rcu_cpu_kthread_task, cpu) = t;
 	sp.sched_priority = RCU_KTHREAD_PRIO;
 	sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+	per_cpu(rcu_cpu_kthread_task, cpu) = t;
+	wake_up_process(t); /* Get to TASK_INTERRUPTIBLE quickly. */
 	return 0;
 }
 

@@ -1758,12 +1774,11 @@ static int __cpuinit rcu_spawn_one_node_kthread(struct rcu_state *rsp,
 		raw_spin_unlock_irqrestore(&rnp->lock, flags);
 		sp.sched_priority = 99;
 		sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+		wake_up_process(t); /* get to TASK_INTERRUPTIBLE quickly. */
 	}
 	return rcu_spawn_one_boost_kthread(rsp, rnp, rnp_index);
 }
 
-static void rcu_wake_one_boost_kthread(struct rcu_node *rnp);
-
 /*
  * Spawn all kthreads -- called as soon as the scheduler is running.
  */

@@ -1771,30 +1786,18 @@ static int __init rcu_spawn_kthreads(void)
 {
 	int cpu;
 	struct rcu_node *rnp;
-	struct task_struct *t;
 
 	rcu_kthreads_spawnable = 1;
 	for_each_possible_cpu(cpu) {
 		per_cpu(rcu_cpu_has_work, cpu) = 0;
-		if (cpu_online(cpu)) {
+		if (cpu_online(cpu))
 			(void)rcu_spawn_one_cpu_kthread(cpu);
-			t = per_cpu(rcu_cpu_kthread_task, cpu);
-			if (t)
-				wake_up_process(t);
-		}
 	}
 	rnp = rcu_get_root(rcu_state);
 	(void)rcu_spawn_one_node_kthread(rcu_state, rnp);
-	if (rnp->node_kthread_task)
-		wake_up_process(rnp->node_kthread_task);
 	if (NUM_RCU_NODES > 1) {
-		rcu_for_each_leaf_node(rcu_state, rnp) {
+		rcu_for_each_leaf_node(rcu_state, rnp)
 			(void)rcu_spawn_one_node_kthread(rcu_state, rnp);
-			t = rnp->node_kthread_task;
-			if (t)
-				wake_up_process(t);
-			rcu_wake_one_boost_kthread(rnp);
-		}
 	}
 	return 0;
 }

@@ -2220,31 +2223,6 @@ static void __cpuinit rcu_prepare_kthreads(int cpu)
 }
 
 /*
- * kthread_create() creates threads in TASK_UNINTERRUPTIBLE state,
- * but the RCU threads are woken on demand, and if demand is low this
- * could be a while triggering the hung task watchdog.
- *
- * In order to avoid this, poke all tasks once the CPU is fully
- * up and running.
- */
-static void __cpuinit rcu_online_kthreads(int cpu)
-{
-	struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, cpu);
-	struct rcu_node *rnp = rdp->mynode;
-	struct task_struct *t;
-
-	t = per_cpu(rcu_cpu_kthread_task, cpu);
-	if (t)
-		wake_up_process(t);
-
-	t = rnp->node_kthread_task;
-	if (t)
-		wake_up_process(t);
-
-	rcu_wake_one_boost_kthread(rnp);
-}
-
-/*
  * Handle CPU online/offline notification events.
  */
 static int __cpuinit rcu_cpu_notify(struct notifier_block *self,

@@ -2261,7 +2239,6 @@ static int __cpuinit rcu_cpu_notify(struct notifier_block *self,
 		rcu_prepare_kthreads(cpu);
 		break;
 	case CPU_ONLINE:
-		rcu_online_kthreads(cpu);
 	case CPU_DOWN_FAILED:
 		rcu_node_kthread_setaffinity(rnp, -1);
 		rcu_cpu_kthread_setrt(cpu, 1);

index c8bff30..ea2e2fb 100644
@@ -1299,15 +1299,10 @@ static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
 	raw_spin_unlock_irqrestore(&rnp->lock, flags);
 	sp.sched_priority = RCU_KTHREAD_PRIO;
 	sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+	wake_up_process(t); /* get to TASK_INTERRUPTIBLE quickly. */
 	return 0;
 }
 
-static void __cpuinit rcu_wake_one_boost_kthread(struct rcu_node *rnp)
-{
-	if (rnp->boost_kthread_task)
-		wake_up_process(rnp->boost_kthread_task);
-}
-
 #else /* #ifdef CONFIG_RCU_BOOST */
 
 static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags)

@@ -1331,10 +1326,6 @@ static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
 	return 0;
 }
 
-static void __cpuinit rcu_wake_one_boost_kthread(struct rcu_node *rnp)
-{
-}
-
 #endif /* #else #ifdef CONFIG_RCU_BOOST */
 
 #ifndef CONFIG_SMP

index 2e138db..40d9ed2 100644
@@ -1282,7 +1282,8 @@ static int rcutorture_booster_init(int cpu)
 	/* Don't allow time recalculation while creating a new task. */
 	mutex_lock(&boost_mutex);
 	VERBOSE_PRINTK_STRING("Creating rcu_torture_boost task");
-	boost_tasks[cpu] = kthread_create(rcu_torture_boost, NULL,
+	boost_tasks[cpu] = kthread_create_on_node(rcu_torture_boost, NULL,
+						  cpu_to_node(cpu),
 					  "rcu_torture_boost");
 	if (IS_ERR(boost_tasks[cpu])) {
 		retval = PTR_ERR(boost_tasks[cpu]);

index 36e79d2..c67b9f4 100644
@@ -1657,7 +1657,10 @@ static int __cpuinit rcu_spawn_one_cpu_kthread(int cpu)
 	if (!rcu_kthreads_spawnable ||
 	    per_cpu(rcu_cpu_kthread_task, cpu) != NULL)
 		return 0;
-	t = kthread_create(rcu_cpu_kthread, (void *)(long)cpu, "rcuc%d", cpu);
+	t = kthread_create_on_node(rcu_cpu_kthread,
+				   (void *)(long)cpu,
+				   cpu_to_node(cpu),
+				   "rcuc%d", cpu);
 	if (IS_ERR(t))
 		return PTR_ERR(t);
 	if (cpu_online(cpu))

index ea2e2fb..40a6db7 100644
@@ -284,7 +284,7 @@ static struct list_head *rcu_next_node_entry(struct task_struct *t,
  * notify RCU core processing or task having blocked during the RCU
  * read-side critical section.
  */
-static void rcu_read_unlock_special(struct task_struct *t)
+static noinline void rcu_read_unlock_special(struct task_struct *t)
 {
 	int empty;
 	int empty_exp;

@@ -387,11 +387,11 @@ void __rcu_read_unlock(void)
 	struct task_struct *t = current;
 
 	barrier();  /* needed if we ever invoke rcu_read_unlock in rcutree.c */
-	--t->rcu_read_lock_nesting;
-	barrier();  /* decrement before load of ->rcu_read_unlock_special */
-	if (t->rcu_read_lock_nesting == 0 &&
-	    unlikely(ACCESS_ONCE(t->rcu_read_unlock_special)))
-		rcu_read_unlock_special(t);
+	if (--t->rcu_read_lock_nesting == 0) {
+		barrier();  /* decr before ->rcu_read_unlock_special load */
+		if (unlikely(ACCESS_ONCE(t->rcu_read_unlock_special)))
+			rcu_read_unlock_special(t);
+	}
 #ifdef CONFIG_PROVE_LOCKING
 	WARN_ON_ONCE(ACCESS_ONCE(t->rcu_read_lock_nesting) < 0);
 #endif /* #ifdef CONFIG_PROVE_LOCKING */

index 4aef1dd..bfa66e7 100644
@@ -545,7 +545,7 @@ do {									\
 #endif
 
 #ifdef CONFIG_PROVE_RCU
-extern void lockdep_rcu_dereference(const char *file, const int line);
+void lockdep_rcu_suspicious(const char *file, const int line, const char *s);
 #endif
 
 #endif /* __LINUX_LOCKDEP_H */

index 99f9aa7..8be0433 100644
@@ -297,19 +297,31 @@ extern int rcu_my_thread_group_empty(void);
 /**
  * rcu_lockdep_assert - emit lockdep splat if specified condition not met
  * @c: condition to check
+ * @s: informative message
  */
-#define rcu_lockdep_assert(c)						\
+#define rcu_lockdep_assert(c, s)					\
 	do {								\
 		static bool __warned;					\
 		if (debug_lockdep_rcu_enabled() && !__warned && !(c)) {	\
 			__warned = true;				\
-			lockdep_rcu_dereference(__FILE__, __LINE__);	\
+			lockdep_rcu_suspicious(__FILE__, __LINE__, s);	\
 		}							\
 	} while (0)
 
+#define rcu_sleep_check()						\
+	do {								\
+		rcu_lockdep_assert(!lock_is_held(&rcu_bh_lock_map),	\
+				   "Illegal context switch in RCU-bh"	\
+				   " read-side critical section");	\
+		rcu_lockdep_assert(!lock_is_held(&rcu_sched_lock_map),	\
+				   "Illegal context switch in RCU-sched"\
+				   " read-side critical section");	\
+	} while (0)
+
 #else /* #ifdef CONFIG_PROVE_RCU */
 
-#define rcu_lockdep_assert(c) do { } while (0)
+#define rcu_lockdep_assert(c, s) do { } while (0)
+#define rcu_sleep_check() do { } while (0)
 
 #endif /* #else #ifdef CONFIG_PROVE_RCU */
 

@@ -338,14 +350,16 @@ extern int rcu_my_thread_group_empty(void);
 #define __rcu_dereference_check(p, c, space) \
 	({ \
 		typeof(*p) *_________p1 = (typeof(*p)*__force )ACCESS_ONCE(p); \
-		rcu_lockdep_assert(c); \
+		rcu_lockdep_assert(c, "suspicious rcu_dereference_check()" \
+				      " usage"); \
 		rcu_dereference_sparse(p, space); \
 		smp_read_barrier_depends(); \
 		((typeof(*p) __force __kernel *)(_________p1)); \
 	})
 #define __rcu_dereference_protected(p, c, space) \
 	({ \
-		rcu_lockdep_assert(c); \
+		rcu_lockdep_assert(c, "suspicious rcu_dereference_protected()" \
+				      " usage"); \
 		rcu_dereference_sparse(p, space); \
 		((typeof(*p) __force __kernel *)(p)); \
 	})

@@ -359,7 +373,9 @@ extern int rcu_my_thread_group_empty(void);
 #define __rcu_dereference_index_check(p, c) \
 	({ \
 		typeof(p) _________p1 = ACCESS_ONCE(p); \
-		rcu_lockdep_assert(c); \
+		rcu_lockdep_assert(c, \
+				   "suspicious rcu_dereference_index_check()" \
+				   " usage"); \
 		smp_read_barrier_depends(); \
 		(_________p1); \
 	})

165 lines not on this page · raw message

index 57a8346..a7577b3 100644
@@ -419,7 +419,9 @@ EXPORT_SYMBOL(pid_task);
  */
 struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns)
 {
-	rcu_lockdep_assert(rcu_read_lock_held());
+	rcu_lockdep_assert(rcu_read_lock_held(),
+			   "find_task_by_pid_ns() needs rcu_read_lock()"
+			   " protection");
 	return pid_task(find_pid_ns(nr, ns), PIDTYPE_PID);
 }
 

index 312f8b9..1352dbb 100644
@@ -4021,6 +4021,7 @@ static inline void schedule_debug(struct task_struct *prev)
 	 */
 	if (unlikely(in_atomic_preempt_off() && !prev->exit_state))
 		__schedule_bug(prev);
+	rcu_sleep_check();
 
 	profile_hit(SCHED_PROFILING, __builtin_return_address(0));
 

@@ -8309,6 +8310,7 @@ void __might_sleep(const char *file, int line, int preempt_offset)
 #ifdef in_atomic
 	static unsigned long prev_jiffy;	/* ratelimiting */
 
+	rcu_sleep_check(); /* WARN_ON_ONCE() by default, no rate limit reqd. */
 	if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) ||
 	    system_state != SYSTEM_RUNNING || oops_in_progress)
 		return;

index 8be0433..ad09eb8 100644
@@ -64,15 +64,7 @@ static inline void rcutorture_record_progress(unsigned long vernum)
 #define ULONG_CMP_GE(a, b)	(ULONG_MAX / 2 >= (a) - (b))
 #define ULONG_CMP_LT(a, b)	(ULONG_MAX / 2 < (a) - (b))
 
-/**
- * struct rcu_head - callback structure for use with RCU
- * @next: next update requests in a list
- * @func: actual update function to call after the grace period.
- */
-struct rcu_head {
-	struct rcu_head *next;
-	void (*func)(struct rcu_head *head);
-};
+#include <linux/types.h>
 
 /* Exported common interfaces */
 extern void call_rcu_sched(struct rcu_head *head,

index 176da8c..57a9723 100644
@@ -238,6 +238,16 @@ struct ustat {
 	char			f_fpack[6];
 };
 
+/**
+ * struct rcu_head - callback structure for use with RCU
+ * @next: next update requests in a list
+ * @func: actual update function to call after the grace period.
+ */
+struct rcu_head {
+	struct rcu_head *next;
+	void (*func)(struct rcu_head *head);
+};
+
 #endif	/* __KERNEL__ */
 #endif /*  __ASSEMBLY__ */
 #endif /* _LINUX_TYPES_H */

index 9678cc3..91c56e5 100644
@@ -47,7 +47,7 @@
 #include "rcutree.h"
 
 DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
-DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_cpu);
+DECLARE_PER_CPU(int, rcu_cpu_kthread_cpu);
 DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
 DECLARE_PER_CPU(char, rcu_cpu_has_work);
 

index ad09eb8..9db50df 100644
@@ -67,11 +67,73 @@ static inline void rcutorture_record_progress(unsigned long vernum)
 #include <linux/types.h>
 
 /* Exported common interfaces */
+
+#ifdef CONFIG_PREEMPT_RCU
+
+/**
+ * call_rcu() - Queue an RCU callback for invocation after a grace period.
+ * @head: structure to be used for queueing the RCU updates.
+ * @func: actual callback function to be invoked after the grace period
+ *
+ * The callback function will be invoked some time after a full grace
+ * period elapses, in other words after all pre-existing RCU read-side
+ * critical sections have completed.  However, the callback function
+ * might well execute concurrently with RCU read-side critical sections
+ * that started after call_rcu() was invoked.  RCU read-side critical
+ * sections are delimited by rcu_read_lock() and rcu_read_unlock(),
+ * and may be nested.
+ */
+extern void call_rcu(struct rcu_head *head,
+			      void (*func)(struct rcu_head *head));
+
+#else /* #ifdef CONFIG_PREEMPT_RCU */
+
+/* In classic RCU, call_rcu() is just call_rcu_sched(). */
+#define	call_rcu	call_rcu_sched
+
+#endif /* #else #ifdef CONFIG_PREEMPT_RCU */
+
+/**
+ * call_rcu_bh() - Queue an RCU for invocation after a quicker grace period.
+ * @head: structure to be used for queueing the RCU updates.
+ * @func: actual callback function to be invoked after the grace period
+ *
+ * The callback function will be invoked some time after a full grace
+ * period elapses, in other words after all currently executing RCU
+ * read-side critical sections have completed. call_rcu_bh() assumes
+ * that the read-side critical sections end on completion of a softirq
+ * handler. This means that read-side critical sections in process
+ * context must not be interrupted by softirqs. This interface is to be
+ * used when most of the read-side critical sections are in softirq context.
+ * RCU read-side critical sections are delimited by :
+ *  - rcu_read_lock() and  rcu_read_unlock(), if in interrupt context.
+ *  OR
+ *  - rcu_read_lock_bh() and rcu_read_unlock_bh(), if in process context.
+ *  These may be nested.
+ */
+extern void call_rcu_bh(struct rcu_head *head,
+			void (*func)(struct rcu_head *head));
+
+/**
+ * call_rcu_sched() - Queue an RCU for invocation after sched grace period.
+ * @head: structure to be used for queueing the RCU updates.
+ * @func: actual callback function to be invoked after the grace period
+ *
+ * The callback function will be invoked some time after a full grace
+ * period elapses, in other words after all currently executing RCU
+ * read-side critical sections have completed. call_rcu_sched() assumes
+ * that the read-side critical sections end on enabling of preemption
+ * or on voluntary preemption.
+ * RCU read-side critical sections are delimited by :
+ *  - rcu_read_lock_sched() and  rcu_read_unlock_sched(),
+ *  OR
+ *  anything that disables preemption.
+ *  These may be nested.
+ */
 extern void call_rcu_sched(struct rcu_head *head,
 			   void (*func)(struct rcu_head *rcu));
+
 extern void synchronize_sched(void);
-extern void rcu_barrier_bh(void);
-extern void rcu_barrier_sched(void);
 
 static inline void __rcu_read_lock_bh(void)
 {

@@ -144,6 +206,15 @@ static inline void rcu_exit_nohz(void)
 
 #endif /* #else #ifdef CONFIG_NO_HZ */
 
+/*
+ * Infrastructure to implement the synchronize_() primitives in
+ * TREE_RCU and rcu_barrier_() primitives in TINY_RCU.
+ */
+
+typedef void call_rcu_func_t(struct rcu_head *head,
+			     void (*func)(struct rcu_head *head));
+void wait_rcu_gp(call_rcu_func_t crf);
+
 #if defined(CONFIG_TREE_RCU) || defined(CONFIG_TREE_PREEMPT_RCU)
 #include <linux/rcutree.h>
 #elif defined(CONFIG_TINY_RCU) || defined(CONFIG_TINY_PREEMPT_RCU)

@@ -724,61 +795,6 @@ static inline notrace void rcu_read_unlock_sched_notrace(void)
 #define RCU_INIT_POINTER(p, v) \
 		p = (typeof(*v) __force __rcu *)(v)
 
-/* Infrastructure to implement the synchronize_() primitives. */
-
-struct rcu_synchronize {
-	struct rcu_head head;
-	struct completion completion;
-};
-
-extern void wakeme_after_rcu(struct rcu_head  *head);
-
-#ifdef CONFIG_PREEMPT_RCU
-
-/**
- * call_rcu() - Queue an RCU callback for invocation after a grace period.
- * @head: structure to be used for queueing the RCU updates.
- * @func: actual callback function to be invoked after the grace period
- *
- * The callback function will be invoked some time after a full grace
- * period elapses, in other words after all pre-existing RCU read-side
- * critical sections have completed.  However, the callback function
- * might well execute concurrently with RCU read-side critical sections
- * that started after call_rcu() was invoked.  RCU read-side critical
- * sections are delimited by rcu_read_lock() and rcu_read_unlock(),
- * and may be nested.
- */
-extern void call_rcu(struct rcu_head *head,
-			      void (*func)(struct rcu_head *head));
-
-#else /* #ifdef CONFIG_PREEMPT_RCU */
-
-/* In classic RCU, call_rcu() is just call_rcu_sched(). */
-#define	call_rcu	call_rcu_sched
-
-#endif /* #else #ifdef CONFIG_PREEMPT_RCU */
-
-/**
- * call_rcu_bh() - Queue an RCU for invocation after a quicker grace period.
- * @head: structure to be used for queueing the RCU updates.
- * @func: actual callback function to be invoked after the grace period
- *
- * The callback function will be invoked some time after a full grace
- * period elapses, in other words after all currently executing RCU
- * read-side critical sections have completed. call_rcu_bh() assumes
- * that the read-side critical sections end on completion of a softirq
- * handler. This means that read-side critical sections in process
- * context must not be interrupted by softirqs. This interface is to be
- * used when most of the read-side critical sections are in softirq context.
- * RCU read-side critical sections are delimited by :
- *  - rcu_read_lock() and  rcu_read_unlock(), if in interrupt context.
- *  OR
- *  - rcu_read_lock_bh() and rcu_read_unlock_bh(), if in process context.
- *  These may be nested.
- */
-extern void call_rcu_bh(struct rcu_head *head,
-			void (*func)(struct rcu_head *head));
-
 /*
  * debug_rcu_head_queue()/debug_rcu_head_unqueue() are used internally
  * by call_rcu() and rcu callback execution, and are therefore not part of the

index 52b3e02..4eab233 100644
@@ -31,6 +31,16 @@ static inline void rcu_init(void)
 {
 }
 
+static inline void rcu_barrier_bh(void)
+{
+	wait_rcu_gp(call_rcu_bh);
+}
+
+static inline void rcu_barrier_sched(void)
+{
+	wait_rcu_gp(call_rcu_sched);
+}
+
 #ifdef CONFIG_TINY_RCU
 
 static inline void synchronize_rcu_expedited(void)

@@ -45,9 +55,13 @@ static inline void rcu_barrier(void)
 
 #else /* #ifdef CONFIG_TINY_RCU */
 
-void rcu_barrier(void);
 void synchronize_rcu_expedited(void);
 
+static inline void rcu_barrier(void)
+{
+	wait_rcu_gp(call_rcu);
+}
+
 #endif /* #else #ifdef CONFIG_TINY_RCU */
 
 static inline void synchronize_rcu_bh(void)

index e65d066..6745846 100644
@@ -67,6 +67,8 @@ static inline void synchronize_rcu_bh_expedited(void)
 }
 
 extern void rcu_barrier(void);
+extern void rcu_barrier_bh(void);
+extern void rcu_barrier_sched(void);
 
 extern unsigned long rcutorture_testseq;
 extern unsigned long rcutorture_vernum;

index 7784bd2..a088c90 100644
@@ -94,11 +94,16 @@ EXPORT_SYMBOL_GPL(rcu_read_lock_bh_held);
 
 #endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
 
+struct rcu_synchronize {
+	struct rcu_head head;
+	struct completion completion;
+};
+
 /*
  * Awaken the corresponding synchronize_rcu() instance now that a
  * grace period has elapsed.
  */
-void wakeme_after_rcu(struct rcu_head  *head)
+static void wakeme_after_rcu(struct rcu_head  *head)
 {
 	struct rcu_synchronize *rcu;
 

@@ -106,6 +111,20 @@ void wakeme_after_rcu(struct rcu_head  *head)
 	complete(&rcu->completion);
 }
 
+void wait_rcu_gp(call_rcu_func_t crf)
+{
+	struct rcu_synchronize rcu;
+
+	init_rcu_head_on_stack(&rcu.head);
+	init_completion(&rcu.completion);
+	/* Will wake me after RCU finished. */
+	crf(&rcu.head, wakeme_after_rcu);
+	/* Wait for it. */
+	wait_for_completion(&rcu.completion);
+	destroy_rcu_head_on_stack(&rcu.head);
+}
+EXPORT_SYMBOL_GPL(wait_rcu_gp);
+
 #ifdef CONFIG_PROVE_RCU
 /*
  * wrapper function to avoid #include problems.

index 421abfd..775d69a 100644
@@ -280,34 +280,6 @@ void call_rcu_bh(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
 }
 EXPORT_SYMBOL_GPL(call_rcu_bh);
 
-void rcu_barrier_bh(void)
-{
-	struct rcu_synchronize rcu;
-
-	init_rcu_head_on_stack(&rcu.head);
-	init_completion(&rcu.completion);
-	/* Will wake me after RCU finished. */
-	call_rcu_bh(&rcu.head, wakeme_after_rcu);
-	/* Wait for it. */
-	wait_for_completion(&rcu.completion);
-	destroy_rcu_head_on_stack(&rcu.head);
-}
-EXPORT_SYMBOL_GPL(rcu_barrier_bh);
-
-void rcu_barrier_sched(void)
-{
-	struct rcu_synchronize rcu;
-
-	init_rcu_head_on_stack(&rcu.head);
-	init_completion(&rcu.completion);
-	/* Will wake me after RCU finished. */
-	call_rcu_sched(&rcu.head, wakeme_after_rcu);
-	/* Wait for it. */
-	wait_for_completion(&rcu.completion);
-	destroy_rcu_head_on_stack(&rcu.head);
-}
-EXPORT_SYMBOL_GPL(rcu_barrier_sched);
-
 /*
  * Spawn the kthread that invokes RCU callbacks.
  */

index f259c67..6b0cedb 100644
@@ -697,20 +697,6 @@ void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
 }
 EXPORT_SYMBOL_GPL(call_rcu);
 
-void rcu_barrier(void)
-{
-	struct rcu_synchronize rcu;
-
-	init_rcu_head_on_stack(&rcu.head);
-	init_completion(&rcu.completion);
-	/* Will wake me after RCU finished. */
-	call_rcu(&rcu.head, wakeme_after_rcu);
-	/* Wait for it. */
-	wait_for_completion(&rcu.completion);
-	destroy_rcu_head_on_stack(&rcu.head);
-}
-EXPORT_SYMBOL_GPL(rcu_barrier);
-
 /*
  * synchronize_rcu - wait until a grace period has elapsed.
  *

index c67b9f4..305dfae 100644
@@ -1916,18 +1916,9 @@ EXPORT_SYMBOL_GPL(call_rcu_bh);
  */
 void synchronize_sched(void)
 {
-	struct rcu_synchronize rcu;
-
 	if (rcu_blocking_is_gp())
 		return;
-
-	init_rcu_head_on_stack(&rcu.head);
-	init_completion(&rcu.completion);
-	/* Will wake me after RCU finished. */
-	call_rcu_sched(&rcu.head, wakeme_after_rcu);
-	/* Wait for it. */
-	wait_for_completion(&rcu.completion);
-	destroy_rcu_head_on_stack(&rcu.head);
+	wait_rcu_gp(call_rcu_sched);
 }
 EXPORT_SYMBOL_GPL(synchronize_sched);
 

@@ -1942,18 +1933,9 @@ EXPORT_SYMBOL_GPL(synchronize_sched);
  */
 void synchronize_rcu_bh(void)
 {
-	struct rcu_synchronize rcu;
-
 	if (rcu_blocking_is_gp())
 		return;
-
-	init_rcu_head_on_stack(&rcu.head);
-	init_completion(&rcu.completion);
-	/* Will wake me after RCU finished. */
-	call_rcu_bh(&rcu.head, wakeme_after_rcu);
-	/* Wait for it. */
-	wait_for_completion(&rcu.completion);
-	destroy_rcu_head_on_stack(&rcu.head);
+	wait_rcu_gp(call_rcu_bh);
 }
 EXPORT_SYMBOL_GPL(synchronize_rcu_bh);
 

index 40a6db7..37caa15 100644
@@ -624,18 +624,9 @@ EXPORT_SYMBOL_GPL(call_rcu);
  */
 void synchronize_rcu(void)
 {
-	struct rcu_synchronize rcu;
-
 	if (!rcu_scheduler_active)
 		return;
-
-	init_rcu_head_on_stack(&rcu.head);
-	init_completion(&rcu.completion);
-	/* Will wake me after RCU finished. */
-	call_rcu(&rcu.head, wakeme_after_rcu);
-	/* Wait for it. */
-	wait_for_completion(&rcu.completion);
-	destroy_rcu_head_on_stack(&rcu.head);
+	wait_rcu_gp(call_rcu);
 }
 EXPORT_SYMBOL_GPL(synchronize_rcu);
 

index 40d9ed2..f736fe3 100644
@@ -480,30 +480,6 @@ static void rcu_bh_torture_deferred_free(struct rcu_torture *p)
 	call_rcu_bh(&p->rtort_rcu, rcu_torture_cb);
 }
 
-struct rcu_bh_torture_synchronize {
-	struct rcu_head head;
-	struct completion completion;
-};
-
-static void rcu_bh_torture_wakeme_after_cb(struct rcu_head *head)
-{
-	struct rcu_bh_torture_synchronize *rcu;
-
-	rcu = container_of(head, struct rcu_bh_torture_synchronize, head);
-	complete(&rcu->completion);
-}
-
-static void rcu_bh_torture_synchronize(void)
-{
-	struct rcu_bh_torture_synchronize rcu;
-
-	init_rcu_head_on_stack(&rcu.head);
-	init_completion(&rcu.completion);
-	call_rcu_bh(&rcu.head, rcu_bh_torture_wakeme_after_cb);
-	wait_for_completion(&rcu.completion);
-	destroy_rcu_head_on_stack(&rcu.head);
-}
-
 static struct rcu_torture_ops rcu_bh_ops = {
 	.init		= NULL,
 	.cleanup	= NULL,

@@ -512,7 +488,7 @@ static struct rcu_torture_ops rcu_bh_ops = {
 	.readunlock	= rcu_bh_torture_read_unlock,
 	.completed	= rcu_bh_torture_completed,
 	.deferred_free	= rcu_bh_torture_deferred_free,
-	.sync		= rcu_bh_torture_synchronize,
+	.sync		= synchronize_rcu_bh,
 	.cb_barrier	= rcu_barrier_bh,
 	.fqs		= rcu_bh_force_quiescent_state,
 	.stats		= NULL,

@@ -528,7 +504,7 @@ static struct rcu_torture_ops rcu_bh_sync_ops = {
 	.readunlock	= rcu_bh_torture_read_unlock,
 	.completed	= rcu_bh_torture_completed,
 	.deferred_free	= rcu_sync_torture_deferred_free,
-	.sync		= rcu_bh_torture_synchronize,
+	.sync		= synchronize_rcu_bh,
 	.cb_barrier	= NULL,
 	.fqs		= rcu_bh_force_quiescent_state,
 	.stats		= NULL,

@@ -536,6 +512,22 @@ static struct rcu_torture_ops rcu_bh_sync_ops = {
 	.name		= "rcu_bh_sync"
 };
 
+static struct rcu_torture_ops rcu_bh_expedited_ops = {
+	.init		= rcu_sync_torture_init,
+	.cleanup	= NULL,
+	.readlock	= rcu_bh_torture_read_lock,
+	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
+	.readunlock	= rcu_bh_torture_read_unlock,
+	.completed	= rcu_bh_torture_completed,
+	.deferred_free	= rcu_sync_torture_deferred_free,
+	.sync		= synchronize_rcu_bh_expedited,
+	.cb_barrier	= NULL,
+	.fqs		= rcu_bh_force_quiescent_state,
+	.stats		= NULL,
+	.irq_capable	= 1,
+	.name		= "rcu_bh_expedited"
+};
+
 /*
  * Definitions for srcu torture testing.
  */

@@ -659,11 +651,6 @@ static void rcu_sched_torture_deferred_free(struct rcu_torture *p)
 	call_rcu_sched(&p->rtort_rcu, rcu_torture_cb);
 }
 
-static void sched_torture_synchronize(void)
-{
-	synchronize_sched();
-}
-
 static struct rcu_torture_ops sched_ops = {
 	.init		= rcu_sync_torture_init,
 	.cleanup	= NULL,

@@ -672,7 +659,7 @@ static struct rcu_torture_ops sched_ops = {
 	.readunlock	= sched_torture_read_unlock,
 	.completed	= rcu_no_completed,
 	.deferred_free	= rcu_sched_torture_deferred_free,
-	.sync		= sched_torture_synchronize,
+	.sync		= synchronize_sched,
 	.cb_barrier	= rcu_barrier_sched,
 	.fqs		= rcu_sched_force_quiescent_state,
 	.stats		= NULL,

@@ -688,7 +675,7 @@ static struct rcu_torture_ops sched_sync_ops = {
 	.readunlock	= sched_torture_read_unlock,
 	.completed	= rcu_no_completed,
 	.deferred_free	= rcu_sync_torture_deferred_free,
-	.sync		= sched_torture_synchronize,
+	.sync		= synchronize_sched,
 	.cb_barrier	= NULL,
 	.fqs		= rcu_sched_force_quiescent_state,
 	.stats		= NULL,

@@ -1427,7 +1414,7 @@ rcu_torture_init(void)
 	int firsterr = 0;
 	static struct rcu_torture_ops *torture_ops[] =
 		{ &rcu_ops, &rcu_sync_ops, &rcu_expedited_ops,
-		  &rcu_bh_ops, &rcu_bh_sync_ops,
+		  &rcu_bh_ops, &rcu_bh_sync_ops, &rcu_bh_expedited_ops,
 		  &srcu_ops, &srcu_expedited_ops,
 		  &sched_ops, &sched_sync_ops, &sched_expedited_ops, };
 

index e99dda0..5bf0790 100644
@@ -93,16 +93,10 @@ static inline void get_tree(struct audit_tree *tree)
 	atomic_inc(&tree->count);
 }
 
-static void __put_tree(struct rcu_head *rcu)
-{
-	struct audit_tree *tree = container_of(rcu, struct audit_tree, head);
-	kfree(tree);
-}
-
 static inline void put_tree(struct audit_tree *tree)
 {
 	if (atomic_dec_and_test(&tree->count))
-		call_rcu(&tree->head, __put_tree);
+		kfree_rcu(tree, head);
 }
 
 /* to avoid bringing the entire thing in audit.h */

index 5b52011..6f2a460 100644
@@ -3816,11 +3816,6 @@ static void cfq_put_async_queues(struct cfq_data *cfqd)
 		cfq_put_queue(cfqd->async_idle_cfqq);
 }
 
-static void cfq_cfqd_free(struct rcu_head *head)
-{
-	kfree(container_of(head, struct cfq_data, rcu));
-}
-
 static void cfq_exit_queue(struct elevator_queue *e)
 {
 	struct cfq_data *cfqd = e->elevator_data;

@@ -3854,7 +3849,7 @@ static void cfq_exit_queue(struct elevator_queue *e)
 	spin_unlock(&cic_index_lock);
 
 	/* Wait for cfqg->blkg->key accessors to exit their grace periods. */
-	call_rcu(&cfqd->rcu, cfq_cfqd_free);
+	kfree_rcu(cfqd, rcu);
 }
 
 static int cfq_alloc_cic_index(void)

index bbbc6bf..dd25c2a 100644
@@ -21,25 +21,13 @@
 #include "delegation.h"
 #include "internal.h"
 
-static void nfs_do_free_delegation(struct nfs_delegation *delegation)
-{
-	kfree(delegation);
-}
-
-static void nfs_free_delegation_callback(struct rcu_head *head)
-{
-	struct nfs_delegation *delegation = container_of(head, struct nfs_delegation, rcu);
-
-	nfs_do_free_delegation(delegation);
-}
-
 static void nfs_free_delegation(struct nfs_delegation *delegation)
 {
 	if (delegation->cred) {
 		put_rpccred(delegation->cred);
 		delegation->cred = NULL;
 	}
-	call_rcu(&delegation->rcu, nfs_free_delegation_callback);
+	kfree_rcu(delegation, rcu);
 }
 
 /**

index 8d9c48f..e886ab5 100644
@@ -126,14 +126,6 @@ static int dev_whitelist_add(struct dev_cgroup *dev_cgroup,
 	return 0;
 }
 
-static void whitelist_item_free(struct rcu_head *rcu)
-{
-	struct dev_whitelist_item *item;
-
-	item = container_of(rcu, struct dev_whitelist_item, rcu);
-	kfree(item);
-}
-
 /*
  * called under devcgroup_mutex
  */

@@ -156,7 +148,7 @@ remove:
 		walk->access &= ~wh->access;
 		if (!walk->access) {
 			list_del_rcu(&walk->list);
-			call_rcu(&walk->rcu, whitelist_item_free);
+			kfree_rcu(walk, rcu);
 		}
 	}
 }

index 49e1ccc..01e13a2 100644
@@ -153,18 +153,6 @@ static struct fc_rport_priv *fc_rport_create(struct fc_lport *lport,
 }
 
 /**
- * fc_rport_free_rcu() - Free a remote port
- * @rcu: The rcu_head structure inside the remote port
- */
-static void fc_rport_free_rcu(struct rcu_head *rcu)
-{
-	struct fc_rport_priv *rdata;
-
-	rdata = container_of(rcu, struct fc_rport_priv, rcu);
-	kfree(rdata);
-}
-
-/**
  * fc_rport_destroy() - Free a remote port after last reference is released
  * @kref: The remote port's kref
  */

@@ -173,7 +161,7 @@ static void fc_rport_destroy(struct kref *kref)
 	struct fc_rport_priv *rdata;
 
 	rdata = container_of(kref, struct fc_rport_priv, kref);
-	call_rcu(&rdata->rcu, fc_rport_free_rcu);
+	kfree_rcu(rdata, rcu);
 }
 
 /**

index 2dd9887..f076b5b 100644
@@ -1018,14 +1018,6 @@ static const struct attribute_group *disk_attr_groups[] = {
 	NULL
 };
 
-static void disk_free_ptbl_rcu_cb(struct rcu_head *head)
-{
-	struct disk_part_tbl *ptbl =
-		container_of(head, struct disk_part_tbl, rcu_head);
-
-	kfree(ptbl);
-}
-
 /**
  * disk_replace_part_tbl - replace disk->part_tbl in RCU-safe way
  * @disk: disk to replace part_tbl for

@@ -1046,7 +1038,7 @@ static void disk_replace_part_tbl(struct gendisk *disk,
 
 	if (old_ptbl) {
 		rcu_assign_pointer(old_ptbl->last_lookup, NULL);
-		call_rcu(&old_ptbl->rcu_head, disk_free_ptbl_rcu_cb);
+		kfree_rcu(old_ptbl, rcu_head);
 	}
 }
 

index 81a1f4e..485c42d 100644
@@ -112,8 +112,6 @@ static void sn_ack_irq(struct irq_data *data)
 	irq_move_irq(data);
 }
 
-static void sn_irq_info_free(struct rcu_head *head);
-
 struct sn_irq_info *sn_retarget_vector(struct sn_irq_info *sn_irq_info,
 				       nasid_t nasid, int slice)
 {

@@ -177,7 +175,7 @@ struct sn_irq_info *sn_retarget_vector(struct sn_irq_info *sn_irq_info,
 	spin_lock(&sn_irq_info_lock);
 	list_replace_rcu(&sn_irq_info->list, &new_irq_info->list);
 	spin_unlock(&sn_irq_info_lock);
-	call_rcu(&sn_irq_info->rcu, sn_irq_info_free);
+	kfree_rcu(sn_irq_info, rcu);
 
 
 finish_up:

@@ -338,14 +336,6 @@ static void unregister_intr_pda(struct sn_irq_info *sn_irq_info)
 	rcu_read_unlock();
 }
 
-static void sn_irq_info_free(struct rcu_head *head)
-{
-	struct sn_irq_info *sn_irq_info;
-
-	sn_irq_info = container_of(head, struct sn_irq_info, rcu);
-	kfree(sn_irq_info);
-}
-
 void sn_irq_fixup(struct pci_dev *pci_dev, struct sn_irq_info *sn_irq_info)
 {
 	nasid_t nasid = sn_irq_info->irq_nasid;

@@ -399,7 +389,7 @@ void sn_irq_unfixup(struct pci_dev *pci_dev)
 	spin_unlock(&sn_irq_info_lock);
 	if (list_empty(sn_irq_lh[sn_irq_info->irq_irq]))
 		free_irq_vector(sn_irq_info->irq_irq);
-	call_rcu(&sn_irq_info->rcu, sn_irq_info_free);
+	kfree_rcu(sn_irq_info, rcu);
 	pci_dev_put(pci_dev);
 
 }

index e0ec3db..13fb464 100644
@@ -2390,11 +2390,6 @@ struct devname_cache {
 static struct devname_cache *devcache[1 << CACHE_SIZE_BITS];
 static DEFINE_SPINLOCK(devname_cache_lock);
 
-static void free_devcache(struct rcu_head *rcu)
-{
-	kfree(rcu);
-}
-
 const char *jbd2_dev_to_name(dev_t device)
 {
 	int	i = hash_32(device, CACHE_SIZE_BITS);

@@ -2423,7 +2418,7 @@ const char *jbd2_dev_to_name(dev_t device)
 			spin_unlock(&devname_cache_lock);
 			return ret;
 		}
-		call_rcu(&devcache[i]->rcu, free_devcache);
+		kfree_rcu(devcache[i], rcu);
 	}
 	devcache[i] = new_dev;
 	devcache[i]->device = device;

index abfb59a..6cd2c31 100644
@@ -213,12 +213,6 @@ static int linear_run (mddev_t *mddev)
 	return md_integrity_register(mddev);
 }
 
-static void free_conf(struct rcu_head *head)
-{
-	linear_conf_t *conf = container_of(head, linear_conf_t, rcu);
-	kfree(conf);
-}
-
 static int linear_add(mddev_t *mddev, mdk_rdev_t *rdev)
 {
 	/* Adding a drive to a linear array allows the array to grow.

@@ -247,7 +241,7 @@ static int linear_add(mddev_t *mddev, mdk_rdev_t *rdev)
 	md_set_array_sectors(mddev, linear_size(mddev, 0, 0));
 	set_capacity(mddev->gendisk, mddev->array_sectors);
 	revalidate_disk(mddev->gendisk);
-	call_rcu(&oldconf->rcu, free_conf);
+	kfree_rcu(oldconf, rcu);
 	return 0;
 }
 

index 65ebfe9..692b857 100644
@@ -69,22 +69,6 @@ static DEFINE_SPINLOCK(sel_netnode_lock);
 static struct sel_netnode_bkt sel_netnode_hash[SEL_NETNODE_HASH_SIZE];
 
 /**
- * sel_netnode_free - Frees a node entry
- * @p: the entry's RCU field
- *
- * Description:
- * This function is designed to be used as a callback to the call_rcu()
- * function so that memory allocated to a hash table node entry can be
- * released safely.
- *
- */
-static void sel_netnode_free(struct rcu_head *p)
-{
-	struct sel_netnode *node = container_of(p, struct sel_netnode, rcu);
-	kfree(node);
-}
-
-/**
  * sel_netnode_hashfn_ipv4 - IPv4 hashing function for the node table
  * @addr: IPv4 address
  *

@@ -192,7 +176,7 @@ static void sel_netnode_insert(struct sel_netnode *node)
 			rcu_dereference(sel_netnode_hash[idx].list.prev),
 			struct sel_netnode, list);
 		list_del_rcu(&tail->list);
-		call_rcu(&tail->rcu, sel_netnode_free);
+		kfree_rcu(tail, rcu);
 	} else
 		sel_netnode_hash[idx].size++;
 }

@@ -305,7 +289,7 @@ static void sel_netnode_flush(void)
 		list_for_each_entry_safe(node, node_tmp,
 					 &sel_netnode_hash[idx].list, list) {
 				list_del_rcu(&node->list);
-				call_rcu(&node->rcu, sel_netnode_free);
+				kfree_rcu(node, rcu);
 		}
 		sel_netnode_hash[idx].size = 0;
 	}

index cfe2d72..ae76e29 100644
@@ -68,22 +68,6 @@ static DEFINE_SPINLOCK(sel_netport_lock);
 static struct sel_netport_bkt sel_netport_hash[SEL_NETPORT_HASH_SIZE];
 
 /**
- * sel_netport_free - Frees a port entry
- * @p: the entry's RCU field
- *
- * Description:
- * This function is designed to be used as a callback to the call_rcu()
- * function so that memory allocated to a hash table port entry can be
- * released safely.
- *
- */
-static void sel_netport_free(struct rcu_head *p)
-{
-	struct sel_netport *port = container_of(p, struct sel_netport, rcu);
-	kfree(port);
-}
-
-/**
  * sel_netport_hashfn - Hashing function for the port table
  * @pnum: port number
  *

@@ -142,7 +126,7 @@ static void sel_netport_insert(struct sel_netport *port)
 			rcu_dereference(sel_netport_hash[idx].list.prev),
 			struct sel_netport, list);
 		list_del_rcu(&tail->list);
-		call_rcu(&tail->rcu, sel_netport_free);
+		kfree_rcu(tail, rcu);
 	} else
 		sel_netport_hash[idx].size++;
 }

@@ -241,7 +225,7 @@ static void sel_netport_flush(void)
 		list_for_each_entry_safe(port, port_tmp,
 					 &sel_netport_hash[idx].list, list) {
 			list_del_rcu(&port->list);
-			call_rcu(&port->rcu, sel_netport_free);
+			kfree_rcu(port, rcu);
 		}
 		sel_netport_hash[idx].size = 0;
 	}

index 34193ed..8b929e6 100644
@@ -689,12 +689,6 @@ static int count_semzcnt (struct sem_array * sma, ushort semnum)
 	return semzcnt;
 }
 
-static void free_un(struct rcu_head *head)
-{
-	struct sem_undo *un = container_of(head, struct sem_undo, rcu);
-	kfree(un);
-}
-
 /* Free a semaphore set. freeary() is called with sem_ids.rw_mutex locked
  * as a writer and the spinlock for this semaphore set hold. sem_ids.rw_mutex
  * remains locked on exit.

@@ -714,7 +708,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
 		un->semid = -1;
 		list_del_rcu(&un->list_proc);
 		spin_unlock(&un->ulp->lock);
-		call_rcu(&un->rcu, free_un);
+		kfree_rcu(un, rcu);
 	}
 
 	/* Wake up all pending processes and let them fail with EIDRM. */

@@ -1612,7 +1606,7 @@ void exit_sem(struct task_struct *tsk)
 		sem_unlock(sma);
 		wake_up_sem_queue_do(&tasks);
 
-		call_rcu(&un->rcu, free_un);
+		kfree_rcu(un, rcu);
 	}
 	kfree(ulp);
 }

index 5c0d289..75261a3 100644
@@ -579,19 +579,6 @@ static void ipc_schedule_free(struct rcu_head *head)
 	schedule_work(&sched->work);
 }
 
-/**
- * ipc_immediate_free - free ipc + rcu space
- * @head: RCU callback structure that contains pointer to be freed
- *
- * Free from the RCU callback context.
- */
-static void ipc_immediate_free(struct rcu_head *head)
-{
-	struct ipc_rcu_grace *free =
-		container_of(head, struct ipc_rcu_grace, rcu);
-	kfree(free);
-}
-
 void ipc_rcu_putref(void *ptr)
 {
 	if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0)

@@ -601,8 +588,7 @@ void ipc_rcu_putref(void *ptr)
 		call_rcu(&container_of(ptr, struct ipc_rcu_grace, data)->rcu,
 				ipc_schedule_free);
 	} else {
-		call_rcu(&container_of(ptr, struct ipc_rcu_grace, data)->rcu,
-				ipc_immediate_free);
+		kfree_rcu(container_of(ptr, struct ipc_rcu_grace, data), rcu);
 	}
 }
 

index 5d60302..73f56c8 100644
@@ -452,13 +452,6 @@ overflow:
 	return ERR_PTR(-EBUSY);
 }
 
-static void rcu_free_va(struct rcu_head *head)
-{
-	struct vmap_area *va = container_of(head, struct vmap_area, rcu_head);
-
-	kfree(va);
-}
-
 static void __free_vmap_area(struct vmap_area *va)
 {
 	BUG_ON(RB_EMPTY_NODE(&va->rb_node));

@@ -491,7 +484,7 @@ static void __free_vmap_area(struct vmap_area *va)
 	if (va->va_end > VMALLOC_START && va->va_end <= VMALLOC_END)
 		vmap_area_pcpu_hole = max(vmap_area_pcpu_hole, va->va_end);
 
-	call_rcu(&va->rcu_head, rcu_free_va);
+	kfree_rcu(va, rcu_head);
 }
 
 /*

index 73f56c8..6540116 100644
@@ -830,13 +830,6 @@ static struct vmap_block *new_vmap_block(gfp_t gfp_mask)
 	return vb;
 }
 
-static void rcu_free_vb(struct rcu_head *head)
-{
-	struct vmap_block *vb = container_of(head, struct vmap_block, rcu_head);
-
-	kfree(vb);
-}
-
 static void free_vmap_block(struct vmap_block *vb)
 {
 	struct vmap_block *tmp;

@@ -849,7 +842,7 @@ static void free_vmap_block(struct vmap_block *vb)
 	BUG_ON(tmp != vb);
 
 	free_vmap_area_noflush(vb->va);
-	call_rcu(&vb->rcu_head, rcu_free_vb);
+	kfree_rcu(vb, rcu_head);
 }
 
 static void purge_fragmented_blocks(int cpu)

index c0bb324..39dbad0 100644
@@ -1574,16 +1574,11 @@ void sysctl_head_get(struct ctl_table_header *head)
 	spin_unlock(&sysctl_lock);
 }
 
-static void free_head(struct rcu_head *rcu)
-{
-	kfree(container_of(rcu, struct ctl_table_header, rcu));
-}
-
 void sysctl_head_put(struct ctl_table_header *head)
 {
 	spin_lock(&sysctl_lock);
 	if (!--head->count)
-		call_rcu(&head->rcu, free_head);
+		kfree_rcu(head, rcu);
 	spin_unlock(&sysctl_lock);
 }
 

@@ -1955,10 +1950,10 @@ void unregister_sysctl_table(struct ctl_table_header * header)
 	start_unregistering(header);
 	if (!--header->parent->count) {
 		WARN_ON(1);
-		call_rcu(&header->parent->rcu, free_head);
+		kfree_rcu(header->parent, rcu);
 	}
 	if (!--header->count)
-		call_rcu(&header->rcu, free_head);
+		kfree_rcu(header, rcu);
 	spin_unlock(&sysctl_lock);
 }
 

index de079abd..f264032 100644
@@ -60,11 +60,6 @@ struct xt_rateest *xt_rateest_lookup(const char *name)
 }
 EXPORT_SYMBOL_GPL(xt_rateest_lookup);
 
-static void xt_rateest_free_rcu(struct rcu_head *head)
-{
-	kfree(container_of(head, struct xt_rateest, rcu));
-}
-
 void xt_rateest_put(struct xt_rateest *est)
 {
 	mutex_lock(&xt_rateest_mutex);

@@ -75,7 +70,7 @@ void xt_rateest_put(struct xt_rateest *est)
 		 * gen_estimator est_timer() might access est->lock or bstats,
 		 * wait a RCU grace period before freeing 'est'
 		 */
-		call_rcu(&est->rcu, xt_rateest_free_rcu);
+		kfree_rcu(est, rcu);
 	}
 	mutex_unlock(&xt_rateest_mutex);
 }

@@ -188,7 +183,6 @@ static int __init xt_rateest_tg_init(void)
 static void __exit xt_rateest_tg_fini(void)
 {
 	xt_unregister_target(&xt_rateest_tg_reg);
-	rcu_barrier(); /* Wait for completion of call_rcu()'s (xt_rateest_free_rcu) */
 }
 
 

index 01810a3..60caa06 100644
@@ -1179,8 +1179,6 @@ extern void sk_common_release(struct sock *sk);
 /* Initialise core socket variables */
 extern void sock_init_data(struct socket *sock, struct sock *sk);
 
-extern void sk_filter_release_rcu(struct rcu_head *rcu);
-
 /**
  *	sk_filter_release - release a socket filter
  *	@fp: filter to remove

@@ -1191,7 +1189,7 @@ extern void sk_filter_release_rcu(struct rcu_head *rcu);
 static inline void sk_filter_release(struct sk_filter *fp)
 {
 	if (atomic_dec_and_test(&fp->refcnt))
-		call_rcu(&fp->rcu, sk_filter_release_rcu);
+		kfree_rcu(fp, rcu);
 }
 
 static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)

index afb8afb..7195ce0 100644
@@ -631,18 +631,6 @@ int sk_chk_filter(struct sock_filter *filter, int flen)
 EXPORT_SYMBOL(sk_chk_filter);
 
 /**
- * 	sk_filter_release_rcu - Release a socket filter by rcu_head
- *	@rcu: rcu_head that contains the sk_filter to free
- */
-void sk_filter_release_rcu(struct rcu_head *rcu)
-{
-	struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
-
-	kfree(fp);
-}
-EXPORT_SYMBOL(sk_filter_release_rcu);
-
-/**
  *	sk_attach_filter - attach a socket filter
  *	@fprog: the filter program
  *	@sk: the socket to use