rcutree.h 2.3 KB
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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 -
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 *	Documentation/RCU
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 */

#ifndef __LINUX_RCUTREE_H
#define __LINUX_RCUTREE_H

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extern void rcu_init(void);
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extern void rcu_note_context_switch(int cpu);
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extern int rcu_needs_cpu(int cpu);
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extern void rcu_cpu_stall_reset(void);
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#ifdef CONFIG_TREE_PREEMPT_RCU

extern void exit_rcu(void);

#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */

static inline void exit_rcu(void)
{
}

#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */

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extern void synchronize_rcu_bh(void);
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extern void synchronize_sched_expedited(void);
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extern void synchronize_rcu_expedited(void);
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static inline void synchronize_rcu_bh_expedited(void)
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{
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	synchronize_sched_expedited();
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}

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Paul E. McKenney 已提交
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extern void rcu_barrier(void);

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extern long rcu_batches_completed(void);
extern long rcu_batches_completed_bh(void);
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extern long rcu_batches_completed_sched(void);
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extern void rcu_force_quiescent_state(void);
extern void rcu_bh_force_quiescent_state(void);
extern void rcu_sched_force_quiescent_state(void);
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/* A context switch is a grace period for RCU-sched and RCU-bh. */
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static inline int rcu_blocking_is_gp(void)
{
	return num_online_cpus() == 1;
}

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extern void rcu_scheduler_starting(void);
extern int rcu_scheduler_active __read_mostly;

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#endif /* __LINUX_RCUTREE_H */