android_kernel_samsung_msm8976/include/linux/rcutiny.h
Paul E. McKenney d9f1bb6ad7 rcu: Make rcu_read_lock_sched_held() take boot time into account
Before the scheduler starts, all tasks are non-preemptible by
definition. So, during that time, rcu_read_lock_sched_held()
needs to always return "true".  This patch makes that be so.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <1267135607-7056-2-git-send-email-paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-26 08:20:46 +01:00

117 lines
2.5 KiB
C

/*
* Read-Copy Update mechanism for mutual exclusion, the Bloatwatch edition.
*
* 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: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
*
* For detailed explanation of Read-Copy Update mechanism see -
* Documentation/RCU
*/
#ifndef __LINUX_TINY_H
#define __LINUX_TINY_H
#include <linux/cache.h>
void rcu_sched_qs(int cpu);
void rcu_bh_qs(int cpu);
#define __rcu_read_lock() preempt_disable()
#define __rcu_read_unlock() preempt_enable()
#define __rcu_read_lock_bh() local_bh_disable()
#define __rcu_read_unlock_bh() local_bh_enable()
#define call_rcu_sched call_rcu
#define rcu_init_sched() do { } while (0)
extern void rcu_check_callbacks(int cpu, int user);
static inline int rcu_needs_cpu(int cpu)
{
return 0;
}
/*
* Return the number of grace periods.
*/
static inline long rcu_batches_completed(void)
{
return 0;
}
/*
* Return the number of bottom-half grace periods.
*/
static inline long rcu_batches_completed_bh(void)
{
return 0;
}
extern int rcu_expedited_torture_stats(char *page);
static inline void rcu_force_quiescent_state(void)
{
}
static inline void rcu_bh_force_quiescent_state(void)
{
}
static inline void rcu_sched_force_quiescent_state(void)
{
}
#define synchronize_rcu synchronize_sched
static inline void synchronize_rcu_expedited(void)
{
synchronize_sched();
}
static inline void synchronize_rcu_bh_expedited(void)
{
synchronize_sched();
}
struct notifier_block;
#ifdef CONFIG_NO_HZ
extern void rcu_enter_nohz(void);
extern void rcu_exit_nohz(void);
#else /* #ifdef CONFIG_NO_HZ */
static inline void rcu_enter_nohz(void)
{
}
static inline void rcu_exit_nohz(void)
{
}
#endif /* #else #ifdef CONFIG_NO_HZ */
static inline void exit_rcu(void)
{
}
static inline int rcu_preempt_depth(void)
{
return 0;
}
#endif /* __LINUX_RCUTINY_H */