smp.h 4.8 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. #include <linux/llist.h>
  13. typedef void (*smp_call_func_t)(void *info);
  14. struct call_single_data {
  15. struct llist_node llist;
  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. int smp_call_function_single_async(int cpu, struct call_single_data *csd);
  43. #ifdef CONFIG_SMP
  44. #include <linux/preempt.h>
  45. #include <linux/kernel.h>
  46. #include <linux/compiler.h>
  47. #include <linux/thread_info.h>
  48. #include <asm/smp.h>
  49. /*
  50. * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
  51. * (defined in asm header):
  52. */
  53. /*
  54. * stops all CPUs but the current one:
  55. */
  56. extern void smp_send_stop(void);
  57. /*
  58. * sends a 'reschedule' event to another CPU:
  59. */
  60. extern void smp_send_reschedule(int cpu);
  61. /*
  62. * Prepare machine for booting other CPUs.
  63. */
  64. extern void smp_prepare_cpus(unsigned int max_cpus);
  65. /*
  66. * Bring a CPU up
  67. */
  68. extern int __cpu_up(unsigned int cpunum, struct task_struct *tidle);
  69. /*
  70. * Final polishing of CPUs
  71. */
  72. extern void smp_cpus_done(unsigned int max_cpus);
  73. /*
  74. * Call a function on all other processors
  75. */
  76. int smp_call_function(smp_call_func_t func, void *info, int wait);
  77. void smp_call_function_many(const struct cpumask *mask,
  78. smp_call_func_t func, void *info, bool wait);
  79. int smp_call_function_any(const struct cpumask *mask,
  80. smp_call_func_t func, void *info, int wait);
  81. void kick_all_cpus_sync(void);
  82. /*
  83. * Generic and arch helpers
  84. */
  85. void __init call_function_init(void);
  86. void generic_smp_call_function_single_interrupt(void);
  87. #define generic_smp_call_function_interrupt \
  88. generic_smp_call_function_single_interrupt
  89. /*
  90. * Mark the boot cpu "online" so that it can call console drivers in
  91. * printk() and can access its per-cpu storage.
  92. */
  93. void smp_prepare_boot_cpu(void);
  94. extern unsigned int setup_max_cpus;
  95. extern void __init setup_nr_cpu_ids(void);
  96. extern void __init smp_init(void);
  97. #else /* !SMP */
  98. static inline void smp_send_stop(void) { }
  99. /*
  100. * These macros fold the SMP functionality into a single CPU system
  101. */
  102. #define raw_smp_processor_id() 0
  103. static inline int up_smp_call_function(smp_call_func_t func, void *info)
  104. {
  105. return 0;
  106. }
  107. #define smp_call_function(func, info, wait) \
  108. (up_smp_call_function(func, info))
  109. static inline void smp_send_reschedule(int cpu) { }
  110. #define smp_prepare_boot_cpu() do {} while (0)
  111. #define smp_call_function_many(mask, func, info, wait) \
  112. (up_smp_call_function(func, info))
  113. static inline void call_function_init(void) { }
  114. static inline int
  115. smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
  116. void *info, int wait)
  117. {
  118. return smp_call_function_single(0, func, info, wait);
  119. }
  120. static inline void kick_all_cpus_sync(void) { }
  121. #endif /* !SMP */
  122. /*
  123. * smp_processor_id(): get the current CPU ID.
  124. *
  125. * if DEBUG_PREEMPT is enabled then we check whether it is
  126. * used in a preemption-safe way. (smp_processor_id() is safe
  127. * if it's used in a preemption-off critical section, or in
  128. * a thread that is bound to the current CPU.)
  129. *
  130. * NOTE: raw_smp_processor_id() is for internal use only
  131. * (smp_processor_id() is the preferred variant), but in rare
  132. * instances it might also be used to turn off false positives
  133. * (i.e. smp_processor_id() use that the debugging code reports but
  134. * which use for some reason is legal). Don't use this to hack around
  135. * the warning message, as your code might not work under PREEMPT.
  136. */
  137. #ifdef CONFIG_DEBUG_PREEMPT
  138. extern unsigned int debug_smp_processor_id(void);
  139. # define smp_processor_id() debug_smp_processor_id()
  140. #else
  141. # define smp_processor_id() raw_smp_processor_id()
  142. #endif
  143. #define get_cpu() ({ preempt_disable(); smp_processor_id(); })
  144. #define put_cpu() preempt_enable()
  145. /*
  146. * Callback to arch code if there's nosmp or maxcpus=0 on the
  147. * boot command line:
  148. */
  149. extern void arch_disable_smp_support(void);
  150. extern void arch_enable_nonboot_cpus_begin(void);
  151. extern void arch_enable_nonboot_cpus_end(void);
  152. void smp_setup_processor_id(void);
  153. #endif /* __LINUX_SMP_H */