smp.h 3.3 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130
  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/config.h>
  8. extern void cpu_idle(void);
  9. #ifdef CONFIG_SMP
  10. #include <linux/preempt.h>
  11. #include <linux/kernel.h>
  12. #include <linux/compiler.h>
  13. #include <linux/thread_info.h>
  14. #include <asm/smp.h>
  15. /*
  16. * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
  17. * (defined in asm header):
  18. */
  19. /*
  20. * stops all CPUs but the current one:
  21. */
  22. extern void smp_send_stop(void);
  23. /*
  24. * sends a 'reschedule' event to another CPU:
  25. */
  26. extern void smp_send_reschedule(int cpu);
  27. /*
  28. * Prepare machine for booting other CPUs.
  29. */
  30. extern void smp_prepare_cpus(unsigned int max_cpus);
  31. /*
  32. * Bring a CPU up
  33. */
  34. extern int __cpu_up(unsigned int cpunum);
  35. /*
  36. * Final polishing of CPUs
  37. */
  38. extern void smp_cpus_done(unsigned int max_cpus);
  39. /*
  40. * Call a function on all other processors
  41. */
  42. extern int smp_call_function (void (*func) (void *info), void *info,
  43. int retry, int wait);
  44. /*
  45. * Call a function on all processors
  46. */
  47. static inline int on_each_cpu(void (*func) (void *info), void *info,
  48. int retry, int wait)
  49. {
  50. int ret = 0;
  51. preempt_disable();
  52. ret = smp_call_function(func, info, retry, wait);
  53. func(info);
  54. preempt_enable();
  55. return ret;
  56. }
  57. #define MSG_ALL_BUT_SELF 0x8000 /* Assume <32768 CPU's */
  58. #define MSG_ALL 0x8001
  59. #define MSG_INVALIDATE_TLB 0x0001 /* Remote processor TLB invalidate */
  60. #define MSG_STOP_CPU 0x0002 /* Sent to shut down slave CPU's
  61. * when rebooting
  62. */
  63. #define MSG_RESCHEDULE 0x0003 /* Reschedule request from master CPU*/
  64. #define MSG_CALL_FUNCTION 0x0004 /* Call function on all other CPUs */
  65. /*
  66. * Mark the boot cpu "online" so that it can call console drivers in
  67. * printk() and can access its per-cpu storage.
  68. */
  69. void smp_prepare_boot_cpu(void);
  70. #else /* !SMP */
  71. /*
  72. * These macros fold the SMP functionality into a single CPU system
  73. */
  74. #define raw_smp_processor_id() 0
  75. #define hard_smp_processor_id() 0
  76. #define smp_call_function(func,info,retry,wait) ({ 0; })
  77. #define on_each_cpu(func,info,retry,wait) ({ func(info); 0; })
  78. static inline void smp_send_reschedule(int cpu) { }
  79. #define num_booting_cpus() 1
  80. #define smp_prepare_boot_cpu() do {} while (0)
  81. #endif /* !SMP */
  82. /*
  83. * smp_processor_id(): get the current CPU ID.
  84. *
  85. * if DEBUG_PREEMPT is enabled the we check whether it is
  86. * used in a preemption-safe way. (smp_processor_id() is safe
  87. * if it's used in a preemption-off critical section, or in
  88. * a thread that is bound to the current CPU.)
  89. *
  90. * NOTE: raw_smp_processor_id() is for internal use only
  91. * (smp_processor_id() is the preferred variant), but in rare
  92. * instances it might also be used to turn off false positives
  93. * (i.e. smp_processor_id() use that the debugging code reports but
  94. * which use for some reason is legal). Don't use this to hack around
  95. * the warning message, as your code might not work under PREEMPT.
  96. */
  97. #ifdef CONFIG_DEBUG_PREEMPT
  98. extern unsigned int debug_smp_processor_id(void);
  99. # define smp_processor_id() debug_smp_processor_id()
  100. #else
  101. # define smp_processor_id() raw_smp_processor_id()
  102. #endif
  103. #define get_cpu() ({ preempt_disable(); smp_processor_id(); })
  104. #define put_cpu() preempt_enable()
  105. #define put_cpu_no_resched() preempt_enable_no_resched()
  106. #endif /* __LINUX_SMP_H */