include/linux/smp.h

   1 #ifndef __LINUX_SMP_H
   2 #define __LINUX_SMP_H
   3
   4 /*
   5  *      Generic SMP support
   6  *              Alan Cox. <alan@redhat.com>
   7  */
   8
   9 #include <linux/errno.h>
  10 #include <linux/list.h>
  11 #include <linux/cpumask.h>
  12
  13 extern void cpu_idle(void);
  14
  15 struct call_single_data {
  16         struct list_head list;
  17         void (*func) (void *info);
  18         void *info;
  19         unsigned int flags;
  20 };
  21
  22 #ifdef CONFIG_SMP
  23
  24 #include <linux/preempt.h>
  25 #include <linux/kernel.h>
  26 #include <linux/compiler.h>
  27 #include <linux/thread_info.h>
  28 #include <asm/smp.h>
  29
  30 /*
  31  * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
  32  * (defined in asm header):
  33  */
  34
  35 /*
  36  * stops all CPUs but the current one:
  37  */
  38 extern void smp_send_stop(void);
  39
  40 /*
  41  * sends a 'reschedule' event to another CPU:
  42  */
  43 extern void smp_send_reschedule(int cpu);
  44
  45
  46 /*
  47  * Prepare machine for booting other CPUs.
  48  */
  49 extern void smp_prepare_cpus(unsigned int max_cpus);
  50
  51 /*
  52  * Bring a CPU up
  53  */
  54 extern int __cpu_up(unsigned int cpunum);
  55
  56 /*
  57  * Final polishing of CPUs
  58  */
  59 extern void smp_cpus_done(unsigned int max_cpus);
  60
  61 /*
  62  * Call a function on all other processors
  63  */
  64 int smp_call_function(void(*func)(void *info), void *info, int wait);
  65 int smp_call_function_mask(cpumask_t mask, void(*func)(void *info), void *info,
  66                                 int wait);
  67 int smp_call_function_single(int cpuid, void (*func) (void *info), void *info,
  68                                 int wait);
  69 void __smp_call_function_single(int cpuid, struct call_single_data *data);
  70
  71 /*
  72  * Generic and arch helpers
  73  */
  74 #ifdef CONFIG_USE_GENERIC_SMP_HELPERS
  75 void generic_smp_call_function_single_interrupt(void);
  76 void generic_smp_call_function_interrupt(void);
  77 void ipi_call_lock(void);
  78 void ipi_call_unlock(void);
  79 void ipi_call_lock_irq(void);
  80 void ipi_call_unlock_irq(void);
  81 #endif
  82
  83 /*
  84  * Call a function on all processors
  85  */
  86 int on_each_cpu(void (*func) (void *info), void *info, int wait);
  87
  88 #define MSG_ALL_BUT_SELF        0x8000  /* Assume <32768 CPU's */
  89 #define MSG_ALL                 0x8001
  90
  91 #define MSG_INVALIDATE_TLB      0x0001  /* Remote processor TLB invalidate */
  92 #define MSG_STOP_CPU            0x0002  /* Sent to shut down slave CPU's
  93                                          * when rebooting
  94                                          */
  95 #define MSG_RESCHEDULE          0x0003  /* Reschedule request from master CPU*/
  96 #define MSG_CALL_FUNCTION       0x0004  /* Call function on all other CPUs */
  97
  98 /*
  99  * Mark the boot cpu "online" so that it can call console drivers in
 100  * printk() and can access its per-cpu storage.
 101  */
 102 void smp_prepare_boot_cpu(void);
 103
 104 extern unsigned int setup_max_cpus;
 105
 106 #else /* !SMP */
 107
 108 /*
 109  *      These macros fold the SMP functionality into a single CPU system
 110  */
 111 #define raw_smp_processor_id()                  0
 112 static inline int up_smp_call_function(void (*func)(void *), void *info)
 113 {
 114         return 0;
 115 }
 116 #define smp_call_function(func, info, wait) \
 117                         (up_smp_call_function(func, info))
 118 #define on_each_cpu(func,info,wait)             \
 119         ({                                      \
 120                 local_irq_disable();            \
 121                 func(info);                     \
 122                 local_irq_enable();             \
 123                 0;                              \
 124         })
 125 static inline void smp_send_reschedule(int cpu) { }
 126 #define num_booting_cpus()                      1
 127 #define smp_prepare_boot_cpu()                  do {} while (0)
 128 #define smp_call_function_single(cpuid, func, info, wait) \
 129 ({ \
 130         WARN_ON(cpuid != 0);    \
 131         local_irq_disable();    \
 132         (func)(info);           \
 133         local_irq_enable();     \
 134         0;                      \
 135 })
 136 #define smp_call_function_mask(mask, func, info, wait) \
 137                         (up_smp_call_function(func, info))
 138 static inline void init_call_single_data(void)
 139 {
 140 }
 141 #endif /* !SMP */
 142
 143 /*
 144  * smp_processor_id(): get the current CPU ID.
 145  *
 146  * if DEBUG_PREEMPT is enabled the we check whether it is
 147  * used in a preemption-safe way. (smp_processor_id() is safe
 148  * if it's used in a preemption-off critical section, or in
 149  * a thread that is bound to the current CPU.)
 150  *
 151  * NOTE: raw_smp_processor_id() is for internal use only
 152  * (smp_processor_id() is the preferred variant), but in rare
 153  * instances it might also be used to turn off false positives
 154  * (i.e. smp_processor_id() use that the debugging code reports but
 155  * which use for some reason is legal). Don't use this to hack around
 156  * the warning message, as your code might not work under PREEMPT.
 157  */
 158 #ifdef CONFIG_DEBUG_PREEMPT
 159   extern unsigned int debug_smp_processor_id(void);
 160 # define smp_processor_id() debug_smp_processor_id()
 161 #else
 162 # define smp_processor_id() raw_smp_processor_id()
 163 #endif
 164
 165 #define get_cpu()               ({ preempt_disable(); smp_processor_id(); })
 166 #define put_cpu()               preempt_enable()
 167 #define put_cpu_no_resched()    preempt_enable_no_resched()
 168
 169 void smp_setup_processor_id(void);
 170
 171 #endif /* __LINUX_SMP_H */