linux-stable-rt/include/linux/rcutree.h

91 lines
2.7 KiB
C

/*
* 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);
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);
}
#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 */
extern void synchronize_rcu_bh(void);
extern void synchronize_sched_expedited(void);
extern void synchronize_rcu_expedited(void);
static inline void synchronize_rcu_bh_expedited(void)
{
synchronize_sched_expedited();
}
extern void rcu_barrier(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);
/* A context switch is a grace period for RCU-sched and RCU-bh. */
static inline int rcu_blocking_is_gp(void)
{
return num_online_cpus() == 1;
}
extern void rcu_scheduler_starting(void);
extern int rcu_scheduler_active __read_mostly;
#endif /* __LINUX_RCUTREE_H */