1 /*
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
15 * along with this program; if not, you can access it online at
16 * http://www.gnu.org/licenses/gpl-2.0.html.
17 *
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 -
23 * Documentation/RCU
24 */
25 #ifndef __LINUX_TINY_H
26 #define __LINUX_TINY_H
27
28 #include <linux/cache.h>
29
get_state_synchronize_rcu(void)30 static inline unsigned long get_state_synchronize_rcu(void)
31 {
32 return 0;
33 }
34
cond_synchronize_rcu(unsigned long oldstate)35 static inline void cond_synchronize_rcu(unsigned long oldstate)
36 {
37 might_sleep();
38 }
39
rcu_barrier_bh(void)40 static inline void rcu_barrier_bh(void)
41 {
42 wait_rcu_gp(call_rcu_bh);
43 }
44
rcu_barrier_sched(void)45 static inline void rcu_barrier_sched(void)
46 {
47 wait_rcu_gp(call_rcu_sched);
48 }
49
synchronize_rcu_expedited(void)50 static inline void synchronize_rcu_expedited(void)
51 {
52 synchronize_sched(); /* Only one CPU, so pretty fast anyway!!! */
53 }
54
rcu_barrier(void)55 static inline void rcu_barrier(void)
56 {
57 rcu_barrier_sched(); /* Only one CPU, so only one list of callbacks! */
58 }
59
synchronize_rcu_bh(void)60 static inline void synchronize_rcu_bh(void)
61 {
62 synchronize_sched();
63 }
64
synchronize_rcu_bh_expedited(void)65 static inline void synchronize_rcu_bh_expedited(void)
66 {
67 synchronize_sched();
68 }
69
synchronize_sched_expedited(void)70 static inline void synchronize_sched_expedited(void)
71 {
72 synchronize_sched();
73 }
74
kfree_call_rcu(struct rcu_head * head,void (* func)(struct rcu_head * rcu))75 static inline void kfree_call_rcu(struct rcu_head *head,
76 void (*func)(struct rcu_head *rcu))
77 {
78 call_rcu(head, func);
79 }
80
rcu_note_context_switch(int cpu)81 static inline void rcu_note_context_switch(int cpu)
82 {
83 rcu_sched_qs();
84 }
85
86 /*
87 * Take advantage of the fact that there is only one CPU, which
88 * allows us to ignore virtualization-based context switches.
89 */
rcu_virt_note_context_switch(int cpu)90 static inline void rcu_virt_note_context_switch(int cpu)
91 {
92 }
93
94 /*
95 * Return the number of grace periods.
96 */
rcu_batches_completed(void)97 static inline long rcu_batches_completed(void)
98 {
99 return 0;
100 }
101
102 /*
103 * Return the number of bottom-half grace periods.
104 */
rcu_batches_completed_bh(void)105 static inline long rcu_batches_completed_bh(void)
106 {
107 return 0;
108 }
109
rcu_force_quiescent_state(void)110 static inline void rcu_force_quiescent_state(void)
111 {
112 }
113
rcu_bh_force_quiescent_state(void)114 static inline void rcu_bh_force_quiescent_state(void)
115 {
116 }
117
rcu_sched_force_quiescent_state(void)118 static inline void rcu_sched_force_quiescent_state(void)
119 {
120 }
121
show_rcu_gp_kthreads(void)122 static inline void show_rcu_gp_kthreads(void)
123 {
124 }
125
rcu_cpu_stall_reset(void)126 static inline void rcu_cpu_stall_reset(void)
127 {
128 }
129
exit_rcu(void)130 static inline void exit_rcu(void)
131 {
132 }
133
134 #ifdef CONFIG_DEBUG_LOCK_ALLOC
135 extern int rcu_scheduler_active __read_mostly;
136 void rcu_scheduler_starting(void);
137 #else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
rcu_scheduler_starting(void)138 static inline void rcu_scheduler_starting(void)
139 {
140 }
141 #endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */
142
143 #if defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_RCU_TRACE)
144
rcu_is_watching(void)145 static inline bool rcu_is_watching(void)
146 {
147 return __rcu_is_watching();
148 }
149
150 #else /* defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_RCU_TRACE) */
151
rcu_is_watching(void)152 static inline bool rcu_is_watching(void)
153 {
154 return true;
155 }
156
157
158 #endif /* #else defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_RCU_TRACE) */
159
160 #endif /* __LINUX_RCUTINY_H */
161