android_kernel_xiaomi_sm8350/include/linux/rcutiny.h
Paul E. McKenney 7b0b759b65 rcu: combine duplicate code, courtesy of CONFIG_PREEMPT_RCU
The CONFIG_PREEMPT_RCU kernel configuration parameter was recently
re-introduced, but as an indication of the type of RCU (preemptible
vs. non-preemptible) instead of as selecting a given implementation.
This commit uses CONFIG_PREEMPT_RCU to combine duplicate code
from include/linux/rcutiny.h and include/linux/rcutree.h into
include/linux/rcupdate.h.  This commit also combines a few other pieces
of duplicate code that have accumulated.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2010-08-20 09:00:16 -07:00

141 lines
2.9 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>
#define rcu_init_sched() do { } while (0)
#ifdef CONFIG_TINY_RCU
static inline void synchronize_rcu_expedited(void)
{
synchronize_sched(); /* Only one CPU, so pretty fast anyway!!! */
}
static inline void rcu_barrier(void)
{
rcu_barrier_sched(); /* Only one CPU, so only one list of callbacks! */
}
#else /* #ifdef CONFIG_TINY_RCU */
void rcu_barrier(void);
void synchronize_rcu_expedited(void);
#endif /* #else #ifdef CONFIG_TINY_RCU */
static inline void synchronize_rcu_bh(void)
{
synchronize_sched();
}
static inline void synchronize_rcu_bh_expedited(void)
{
synchronize_sched();
}
#ifdef CONFIG_TINY_RCU
static inline void rcu_preempt_note_context_switch(void)
{
}
static inline void exit_rcu(void)
{
}
static inline int rcu_needs_cpu(int cpu)
{
return 0;
}
#else /* #ifdef CONFIG_TINY_RCU */
void rcu_preempt_note_context_switch(void);
extern void exit_rcu(void);
int rcu_preempt_needs_cpu(void);
static inline int rcu_needs_cpu(int cpu)
{
return rcu_preempt_needs_cpu();
}
#endif /* #else #ifdef CONFIG_TINY_RCU */
static inline void rcu_note_context_switch(int cpu)
{
rcu_sched_qs(cpu);
rcu_preempt_note_context_switch();
}
/*
* 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;
}
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)
{
}
static inline void rcu_cpu_stall_reset(void)
{
}
#ifdef CONFIG_DEBUG_LOCK_ALLOC
extern int rcu_scheduler_active __read_mostly;
extern void rcu_scheduler_starting(void);
#else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
static inline void rcu_scheduler_starting(void)
{
}
#endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */
#endif /* __LINUX_RCUTINY_H */