| 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 | |
| 30 | static inline unsigned long get_state_synchronize_rcu(void) |
| 31 | { |
| 32 | return 0; |
| 33 | } |
| 34 | |
| 35 | static inline void cond_synchronize_rcu(unsigned long oldstate) |
| 36 | { |
| 37 | might_sleep(); |
| 38 | } |
| 39 | |
| 40 | static inline unsigned long get_state_synchronize_sched(void) |
| 41 | { |
| 42 | return 0; |
| 43 | } |
| 44 | |
| 45 | static inline void cond_synchronize_sched(unsigned long oldstate) |
| 46 | { |
| 47 | might_sleep(); |
| 48 | } |
| 49 | |
| 50 | static inline void rcu_barrier_bh(void) |
| 51 | { |
| 52 | wait_rcu_gp(call_rcu_bh); |
| 53 | } |
| 54 | |
| 55 | static inline void rcu_barrier_sched(void) |
| 56 | { |
| 57 | wait_rcu_gp(call_rcu_sched); |
| 58 | } |
| 59 | |
| 60 | static inline void synchronize_rcu_expedited(void) |
| 61 | { |
| 62 | synchronize_sched(); /* Only one CPU, so pretty fast anyway!!! */ |
| 63 | } |
| 64 | |
| 65 | static inline void rcu_barrier(void) |
| 66 | { |
| 67 | rcu_barrier_sched(); /* Only one CPU, so only one list of callbacks! */ |
| 68 | } |
| 69 | |
| 70 | static inline void synchronize_rcu_bh(void) |
| 71 | { |
| 72 | synchronize_sched(); |
| 73 | } |
| 74 | |
| 75 | static inline void synchronize_rcu_bh_expedited(void) |
| 76 | { |
| 77 | synchronize_sched(); |
| 78 | } |
| 79 | |
| 80 | static inline void synchronize_sched_expedited(void) |
| 81 | { |
| 82 | synchronize_sched(); |
| 83 | } |
| 84 | |
| 85 | static inline void kfree_call_rcu(struct rcu_head *head, |
| 86 | rcu_callback_t func) |
| 87 | { |
| 88 | call_rcu(head, func); |
| 89 | } |
| 90 | |
| 91 | static inline void rcu_note_context_switch(void) |
| 92 | { |
| 93 | rcu_sched_qs(); |
| 94 | } |
| 95 | |
| 96 | /* |
| 97 | * Take advantage of the fact that there is only one CPU, which |
| 98 | * allows us to ignore virtualization-based context switches. |
| 99 | */ |
| 100 | static inline void rcu_virt_note_context_switch(int cpu) |
| 101 | { |
| 102 | } |
| 103 | |
| 104 | /* |
| 105 | * Return the number of grace periods started. |
| 106 | */ |
| 107 | static inline unsigned long rcu_batches_started(void) |
| 108 | { |
| 109 | return 0; |
| 110 | } |
| 111 | |
| 112 | /* |
| 113 | * Return the number of bottom-half grace periods started. |
| 114 | */ |
| 115 | static inline unsigned long rcu_batches_started_bh(void) |
| 116 | { |
| 117 | return 0; |
| 118 | } |
| 119 | |
| 120 | /* |
| 121 | * Return the number of sched grace periods started. |
| 122 | */ |
| 123 | static inline unsigned long rcu_batches_started_sched(void) |
| 124 | { |
| 125 | return 0; |
| 126 | } |
| 127 | |
| 128 | /* |
| 129 | * Return the number of grace periods completed. |
| 130 | */ |
| 131 | static inline unsigned long rcu_batches_completed(void) |
| 132 | { |
| 133 | return 0; |
| 134 | } |
| 135 | |
| 136 | /* |
| 137 | * Return the number of bottom-half grace periods completed. |
| 138 | */ |
| 139 | static inline unsigned long rcu_batches_completed_bh(void) |
| 140 | { |
| 141 | return 0; |
| 142 | } |
| 143 | |
| 144 | /* |
| 145 | * Return the number of sched grace periods completed. |
| 146 | */ |
| 147 | static inline unsigned long rcu_batches_completed_sched(void) |
| 148 | { |
| 149 | return 0; |
| 150 | } |
| 151 | |
| 152 | static inline void rcu_force_quiescent_state(void) |
| 153 | { |
| 154 | } |
| 155 | |
| 156 | static inline void rcu_bh_force_quiescent_state(void) |
| 157 | { |
| 158 | } |
| 159 | |
| 160 | static inline void rcu_sched_force_quiescent_state(void) |
| 161 | { |
| 162 | } |
| 163 | |
| 164 | static inline void show_rcu_gp_kthreads(void) |
| 165 | { |
| 166 | } |
| 167 | |
| 168 | static inline void rcu_cpu_stall_reset(void) |
| 169 | { |
| 170 | } |
| 171 | |
| 172 | static inline void rcu_idle_enter(void) |
| 173 | { |
| 174 | } |
| 175 | |
| 176 | static inline void rcu_idle_exit(void) |
| 177 | { |
| 178 | } |
| 179 | |
| 180 | static inline void rcu_irq_enter(void) |
| 181 | { |
| 182 | } |
| 183 | |
| 184 | static inline void rcu_irq_exit_irqson(void) |
| 185 | { |
| 186 | } |
| 187 | |
| 188 | static inline void rcu_irq_enter_irqson(void) |
| 189 | { |
| 190 | } |
| 191 | |
| 192 | static inline void rcu_irq_exit(void) |
| 193 | { |
| 194 | } |
| 195 | |
| 196 | static inline void exit_rcu(void) |
| 197 | { |
| 198 | } |
| 199 | |
| 200 | #ifdef CONFIG_DEBUG_LOCK_ALLOC |
| 201 | extern int rcu_scheduler_active __read_mostly; |
| 202 | void rcu_scheduler_starting(void); |
| 203 | #else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */ |
| 204 | static inline void rcu_scheduler_starting(void) |
| 205 | { |
| 206 | } |
| 207 | #endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */ |
| 208 | |
| 209 | #if defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_RCU_TRACE) |
| 210 | |
| 211 | static inline bool rcu_is_watching(void) |
| 212 | { |
| 213 | return __rcu_is_watching(); |
| 214 | } |
| 215 | |
| 216 | #else /* defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_RCU_TRACE) */ |
| 217 | |
| 218 | static inline bool rcu_is_watching(void) |
| 219 | { |
| 220 | return true; |
| 221 | } |
| 222 | |
| 223 | #endif /* #else defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_RCU_TRACE) */ |
| 224 | |
| 225 | static inline void rcu_all_qs(void) |
| 226 | { |
| 227 | barrier(); /* Avoid RCU read-side critical sections leaking across. */ |
| 228 | } |
| 229 | |
| 230 | #endif /* __LINUX_RCUTINY_H */ |