rcutiny.h 2.9 KB

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  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, write to the Free Software
  16. * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  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. #include <linux/cache.h>
  28. static inline void rcu_init(void)
  29. {
  30. }
  31. #ifdef CONFIG_TINY_RCU
  32. static inline void synchronize_rcu_expedited(void)
  33. {
  34. synchronize_sched(); /* Only one CPU, so pretty fast anyway!!! */
  35. }
  36. static inline void rcu_barrier(void)
  37. {
  38. rcu_barrier_sched(); /* Only one CPU, so only one list of callbacks! */
  39. }
  40. #else /* #ifdef CONFIG_TINY_RCU */
  41. void rcu_barrier(void);
  42. void synchronize_rcu_expedited(void);
  43. #endif /* #else #ifdef CONFIG_TINY_RCU */
  44. static inline void synchronize_rcu_bh(void)
  45. {
  46. synchronize_sched();
  47. }
  48. static inline void synchronize_rcu_bh_expedited(void)
  49. {
  50. synchronize_sched();
  51. }
  52. #ifdef CONFIG_TINY_RCU
  53. static inline void rcu_preempt_note_context_switch(void)
  54. {
  55. }
  56. static inline void exit_rcu(void)
  57. {
  58. }
  59. static inline int rcu_needs_cpu(int cpu)
  60. {
  61. return 0;
  62. }
  63. #else /* #ifdef CONFIG_TINY_RCU */
  64. void rcu_preempt_note_context_switch(void);
  65. extern void exit_rcu(void);
  66. int rcu_preempt_needs_cpu(void);
  67. static inline int rcu_needs_cpu(int cpu)
  68. {
  69. return rcu_preempt_needs_cpu();
  70. }
  71. #endif /* #else #ifdef CONFIG_TINY_RCU */
  72. static inline void rcu_note_context_switch(int cpu)
  73. {
  74. rcu_sched_qs(cpu);
  75. rcu_preempt_note_context_switch();
  76. }
  77. /*
  78. * Return the number of grace periods.
  79. */
  80. static inline long rcu_batches_completed(void)
  81. {
  82. return 0;
  83. }
  84. /*
  85. * Return the number of bottom-half grace periods.
  86. */
  87. static inline long rcu_batches_completed_bh(void)
  88. {
  89. return 0;
  90. }
  91. static inline void rcu_force_quiescent_state(void)
  92. {
  93. }
  94. static inline void rcu_bh_force_quiescent_state(void)
  95. {
  96. }
  97. static inline void rcu_sched_force_quiescent_state(void)
  98. {
  99. }
  100. static inline void rcu_cpu_stall_reset(void)
  101. {
  102. }
  103. #ifdef CONFIG_DEBUG_LOCK_ALLOC
  104. extern int rcu_scheduler_active __read_mostly;
  105. extern void rcu_scheduler_starting(void);
  106. #else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
  107. static inline void rcu_scheduler_starting(void)
  108. {
  109. }
  110. #endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */
  111. #endif /* __LINUX_RCUTINY_H */