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diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h
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+/*
+ * Read-Copy Update mechanism for mutual exclusion (tree-based version)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright IBM Corporation, 2008
+ *
+ * Author: Dipankar Sarma <dipankar@in.ibm.com>
+ *	   Paul E. McKenney <paulmck@linux.vnet.ibm.com> Hierarchical algorithm
+ *
+ * Based on the original work by Paul McKenney <paulmck@us.ibm.com>
+ * and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen.
+ *
+ * For detailed explanation of Read-Copy Update mechanism see -
+ *	Documentation/RCU
+ */
+
+#ifndef __LINUX_RCUTREE_H
+#define __LINUX_RCUTREE_H
+
+extern void rcu_init(void);
+extern void rcu_note_context_switch(int cpu);
+extern int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies);
+extern void rcu_cpu_stall_reset(void);
+
+/*
+ * Note a virtualization-based context switch.  This is simply a
+ * wrapper around rcu_note_context_switch(), which allows TINY_RCU
+ * to save a few bytes.
+ */
+static inline void rcu_virt_note_context_switch(int cpu)
+{
+	rcu_note_context_switch(cpu);
+}
+
+extern void synchronize_rcu_bh(void);
+extern void synchronize_sched_expedited(void);
+extern void synchronize_rcu_expedited(void);
+
+void kfree_call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu));
+
+/**
+ * synchronize_rcu_bh_expedited - Brute-force RCU-bh grace period
+ *
+ * Wait for an RCU-bh grace period to elapse, but use a "big hammer"
+ * approach to force the grace period to end quickly.  This consumes
+ * significant time on all CPUs and is unfriendly to real-time workloads,
+ * so is thus not recommended for any sort of common-case code.  In fact,
+ * if you are using synchronize_rcu_bh_expedited() in a loop, please
+ * restructure your code to batch your updates, and then use a single
+ * synchronize_rcu_bh() instead.
+ *
+ * Note that it is illegal to call this function while holding any lock
+ * that is acquired by a CPU-hotplug notifier.  And yes, it is also illegal
+ * to call this function from a CPU-hotplug notifier.  Failing to observe
+ * these restriction will result in deadlock.
+ */
+static inline void synchronize_rcu_bh_expedited(void)
+{
+	synchronize_sched_expedited();
+}
+
+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;
+extern long rcu_batches_completed(void);
+extern long rcu_batches_completed_bh(void);
+extern long rcu_batches_completed_sched(void);
+
+extern void rcu_force_quiescent_state(void);
+extern void rcu_bh_force_quiescent_state(void);
+extern void rcu_sched_force_quiescent_state(void);
+
+extern void rcu_scheduler_starting(void);
+extern int rcu_scheduler_active __read_mostly;
+
+#endif /* __LINUX_RCUTREE_H */