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Paul E. McKenney9b1d82f2009-10-25 19:03:50 -07001/*
2 * Read-Copy Update mechanism for mutual exclusion, the Bloatwatch edition.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
Paul E. McKenney87de1cf2013-12-03 10:02:52 -080015 * along with this program; if not, you can access it online at
16 * http://www.gnu.org/licenses/gpl-2.0.html.
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -070017 *
18 * Copyright IBM Corporation, 2008
19 *
20 * Author: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
21 *
22 * For detailed explanation of Read-Copy Update mechanism see -
Ingo Molnar4ce5b902009-10-26 07:55:55 +010023 * Documentation/RCU
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -070024 */
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -070025#ifndef __LINUX_TINY_H
26#define __LINUX_TINY_H
27
28#include <linux/cache.h>
29
Paul E. McKenney765a3f42014-03-14 16:37:08 -070030static inline unsigned long get_state_synchronize_rcu(void)
31{
32 return 0;
33}
34
35static inline void cond_synchronize_rcu(unsigned long oldstate)
36{
37 might_sleep();
38}
39
Paul E. McKenney2c428182011-05-26 22:14:36 -070040static inline void rcu_barrier_bh(void)
41{
42 wait_rcu_gp(call_rcu_bh);
43}
44
45static inline void rcu_barrier_sched(void)
46{
47 wait_rcu_gp(call_rcu_sched);
48}
49
Paul E. McKenneya57eb942010-06-29 16:49:16 -070050static inline void synchronize_rcu_expedited(void)
Paul E. McKenneyda848c42010-03-30 15:46:01 -070051{
Paul E. McKenneya57eb942010-06-29 16:49:16 -070052 synchronize_sched(); /* Only one CPU, so pretty fast anyway!!! */
Paul E. McKenneyda848c42010-03-30 15:46:01 -070053}
Paul E. McKenney6ebb2372009-11-22 08:53:50 -080054
Paul E. McKenneya57eb942010-06-29 16:49:16 -070055static inline void rcu_barrier(void)
56{
57 rcu_barrier_sched(); /* Only one CPU, so only one list of callbacks! */
58}
59
Paul E. McKenneya57eb942010-06-29 16:49:16 -070060static inline void synchronize_rcu_bh(void)
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -070061{
62 synchronize_sched();
63}
64
65static inline void synchronize_rcu_bh_expedited(void)
66{
67 synchronize_sched();
68}
69
Lai Jiangshan7b27d542010-10-21 11:29:05 +080070static inline void synchronize_sched_expedited(void)
71{
72 synchronize_sched();
73}
74
Paul E. McKenney486e2592012-01-06 14:11:30 -080075static inline void kfree_call_rcu(struct rcu_head *head,
76 void (*func)(struct rcu_head *rcu))
77{
78 call_rcu(head, func);
79}
80
Paul E. McKenneya57eb942010-06-29 16:49:16 -070081static inline void rcu_note_context_switch(int cpu)
82{
83 rcu_sched_qs(cpu);
Paul E. McKenneya57eb942010-06-29 16:49:16 -070084}
85
Paul E. McKenneya57eb942010-06-29 16:49:16 -070086/*
Gleb Natapov29ce8312011-05-04 16:31:03 +030087 * Take advantage of the fact that there is only one CPU, which
88 * allows us to ignore virtualization-based context switches.
89 */
90static inline void rcu_virt_note_context_switch(int cpu)
91{
92}
93
94/*
Paul E. McKenneya57eb942010-06-29 16:49:16 -070095 * Return the number of grace periods.
96 */
97static inline long rcu_batches_completed(void)
98{
99 return 0;
100}
101
102/*
103 * Return the number of bottom-half grace periods.
104 */
105static inline long rcu_batches_completed_bh(void)
106{
107 return 0;
108}
109
110static inline void rcu_force_quiescent_state(void)
111{
112}
113
114static inline void rcu_bh_force_quiescent_state(void)
115{
116}
117
118static inline void rcu_sched_force_quiescent_state(void)
119{
120}
121
Paul E. McKenney53d84e02010-08-10 14:28:53 -0700122static inline void rcu_cpu_stall_reset(void)
123{
124}
125
Paul E. McKenney2439b692013-04-11 10:15:52 -0700126static inline void exit_rcu(void)
127{
128}
129
Paul E. McKenneybbad9372010-04-02 16:17:17 -0700130#ifdef CONFIG_DEBUG_LOCK_ALLOC
Paul E. McKenneybbad9372010-04-02 16:17:17 -0700131extern int rcu_scheduler_active __read_mostly;
Teodora Baluta584dc4c2013-11-11 17:11:23 +0200132void rcu_scheduler_starting(void);
Paul E. McKenneybbad9372010-04-02 16:17:17 -0700133#else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
Paul E. McKenneybbad9372010-04-02 16:17:17 -0700134static inline void rcu_scheduler_starting(void)
135{
136}
Paul E. McKenneybbad9372010-04-02 16:17:17 -0700137#endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */
138
Paul E. McKenney5c173eb2013-09-13 17:20:11 -0700139#if defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_RCU_TRACE)
Paul E. McKenneycc6783f2013-09-06 17:39:49 -0700140
Paul E. McKenney5c173eb2013-09-13 17:20:11 -0700141static inline bool rcu_is_watching(void)
Paul E. McKenneycc6783f2013-09-06 17:39:49 -0700142{
Paul E. McKenney5c173eb2013-09-13 17:20:11 -0700143 return __rcu_is_watching();
Paul E. McKenneycc6783f2013-09-06 17:39:49 -0700144}
145
Paul E. McKenney5c173eb2013-09-13 17:20:11 -0700146#else /* defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_RCU_TRACE) */
147
148static inline bool rcu_is_watching(void)
149{
150 return true;
151}
152
153
154#endif /* #else defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_RCU_TRACE) */
Paul E. McKenneycc6783f2013-09-06 17:39:49 -0700155
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -0700156#endif /* __LINUX_RCUTINY_H */