smp.h 4.9 KB

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  1. #ifndef __LINUX_SMP_H
  2. #define __LINUX_SMP_H
  3. /*
  4. * Generic SMP support
  5. * Alan Cox. <alan@redhat.com>
  6. */
  7. #include <linux/errno.h>
  8. #include <linux/types.h>
  9. #include <linux/list.h>
  10. #include <linux/cpumask.h>
  11. #include <linux/init.h>
  12. extern void cpu_idle(void);
  13. typedef void (*smp_call_func_t)(void *info);
  14. struct call_single_data {
  15. struct list_head list;
  16. smp_call_func_t func;
  17. void *info;
  18. u16 flags;
  19. };
  20. /* total number of cpus in this system (may exceed NR_CPUS) */
  21. extern unsigned int total_cpus;
  22. int smp_call_function_single(int cpuid, smp_call_func_t func, void *info,
  23. int wait);
  24. /*
  25. * Call a function on all processors
  26. */
  27. int on_each_cpu(smp_call_func_t func, void *info, int wait);
  28. /*
  29. * Call a function on processors specified by mask, which might include
  30. * the local one.
  31. */
  32. void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func,
  33. void *info, bool wait);
  34. /*
  35. * Call a function on each processor for which the supplied function
  36. * cond_func returns a positive value. This may include the local
  37. * processor.
  38. */
  39. void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info),
  40. smp_call_func_t func, void *info, bool wait,
  41. gfp_t gfp_flags);
  42. #ifdef CONFIG_SMP
  43. #include <linux/preempt.h>
  44. #include <linux/kernel.h>
  45. #include <linux/compiler.h>
  46. #include <linux/thread_info.h>
  47. #include <asm/smp.h>
  48. /*
  49. * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
  50. * (defined in asm header):
  51. */
  52. /*
  53. * stops all CPUs but the current one:
  54. */
  55. extern void smp_send_stop(void);
  56. /*
  57. * sends a 'reschedule' event to another CPU:
  58. */
  59. extern void smp_send_reschedule(int cpu);
  60. /*
  61. * Prepare machine for booting other CPUs.
  62. */
  63. extern void smp_prepare_cpus(unsigned int max_cpus);
  64. /*
  65. * Bring a CPU up
  66. */
  67. extern int __cpu_up(unsigned int cpunum, struct task_struct *tidle);
  68. /*
  69. * Final polishing of CPUs
  70. */
  71. extern void smp_cpus_done(unsigned int max_cpus);
  72. /*
  73. * Call a function on all other processors
  74. */
  75. int smp_call_function(smp_call_func_t func, void *info, int wait);
  76. void smp_call_function_many(const struct cpumask *mask,
  77. smp_call_func_t func, void *info, bool wait);
  78. void __smp_call_function_single(int cpuid, struct call_single_data *data,
  79. int wait);
  80. int smp_call_function_any(const struct cpumask *mask,
  81. smp_call_func_t func, void *info, int wait);
  82. void kick_all_cpus_sync(void);
  83. /*
  84. * Generic and arch helpers
  85. */
  86. void __init call_function_init(void);
  87. void generic_smp_call_function_single_interrupt(void);
  88. #define generic_smp_call_function_interrupt \
  89. generic_smp_call_function_single_interrupt
  90. /*
  91. * Mark the boot cpu "online" so that it can call console drivers in
  92. * printk() and can access its per-cpu storage.
  93. */
  94. void smp_prepare_boot_cpu(void);
  95. extern unsigned int setup_max_cpus;
  96. extern void __init setup_nr_cpu_ids(void);
  97. extern void __init smp_init(void);
  98. #else /* !SMP */
  99. static inline void smp_send_stop(void) { }
  100. /*
  101. * These macros fold the SMP functionality into a single CPU system
  102. */
  103. #define raw_smp_processor_id() 0
  104. static inline int up_smp_call_function(smp_call_func_t func, void *info)
  105. {
  106. return 0;
  107. }
  108. #define smp_call_function(func, info, wait) \
  109. (up_smp_call_function(func, info))
  110. static inline void smp_send_reschedule(int cpu) { }
  111. #define smp_prepare_boot_cpu() do {} while (0)
  112. #define smp_call_function_many(mask, func, info, wait) \
  113. (up_smp_call_function(func, info))
  114. static inline void call_function_init(void) { }
  115. static inline int
  116. smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
  117. void *info, int wait)
  118. {
  119. return smp_call_function_single(0, func, info, wait);
  120. }
  121. static inline void kick_all_cpus_sync(void) { }
  122. static inline void __smp_call_function_single(int cpuid,
  123. struct call_single_data *data, int wait)
  124. {
  125. on_each_cpu(data->func, data->info, wait);
  126. }
  127. #endif /* !SMP */
  128. /*
  129. * smp_processor_id(): get the current CPU ID.
  130. *
  131. * if DEBUG_PREEMPT is enabled then we check whether it is
  132. * used in a preemption-safe way. (smp_processor_id() is safe
  133. * if it's used in a preemption-off critical section, or in
  134. * a thread that is bound to the current CPU.)
  135. *
  136. * NOTE: raw_smp_processor_id() is for internal use only
  137. * (smp_processor_id() is the preferred variant), but in rare
  138. * instances it might also be used to turn off false positives
  139. * (i.e. smp_processor_id() use that the debugging code reports but
  140. * which use for some reason is legal). Don't use this to hack around
  141. * the warning message, as your code might not work under PREEMPT.
  142. */
  143. #ifdef CONFIG_DEBUG_PREEMPT
  144. extern unsigned int debug_smp_processor_id(void);
  145. # define smp_processor_id() debug_smp_processor_id()
  146. #else
  147. # define smp_processor_id() raw_smp_processor_id()
  148. #endif
  149. #define get_cpu() ({ preempt_disable(); smp_processor_id(); })
  150. #define put_cpu() preempt_enable()
  151. /*
  152. * Callback to arch code if there's nosmp or maxcpus=0 on the
  153. * boot command line:
  154. */
  155. extern void arch_disable_smp_support(void);
  156. void smp_setup_processor_id(void);
  157. #endif /* __LINUX_SMP_H */