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/types.h>
  11 #include <linux/list.h>
  12 #include <linux/cpumask.h>
  13
  14 extern void cpu_idle(void);
  15
  16 struct call_single_data {
  17         struct list_head list;
  18         void (*func) (void *info);
  19         void *info;
  20         u16 flags;
  21         u16 priv;
  22 };
  23
  24 #ifdef CONFIG_SMP
  25
  26 #include <linux/preempt.h>
  27 #include <linux/kernel.h>
  28 #include <linux/compiler.h>
  29 #include <linux/thread_info.h>
  30 #include <asm/smp.h>
  31
  32 /*
  33  * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
  34  * (defined in asm header):
  35  */
  36
  37 /*
  38  * stops all CPUs but the current one:
  39  */
  40 extern void smp_send_stop(void);
  41
  42 /*
  43  * sends a 'reschedule' event to another CPU:
  44  */
  45 extern void smp_send_reschedule(int cpu);
  46
  47
  48 /*
  49  * Prepare machine for booting other CPUs.
  50  */
  51 extern void smp_prepare_cpus(unsigned int max_cpus);
  52
  53 /*
  54  * Bring a CPU up
  55  */
  56 extern int __cpu_up(unsigned int cpunum);
  57
  58 /*
  59  * Final polishing of CPUs
  60  */
  61 extern void smp_cpus_done(unsigned int max_cpus);
  62
  63 /*
  64  * Call a function on all other processors
  65  */
  66 int smp_call_function(void(*func)(void *info), void *info, int wait);
  67 int smp_call_function_mask(cpumask_t mask, void(*func)(void *info), void *info,
  68                                 int wait);
  69 int smp_call_function_single(int cpuid, void (*func) (void *info), void *info,
  70                                 int wait);
  71 void __smp_call_function_single(int cpuid, struct call_single_data *data);
  72
  73 /*
  74  * Generic and arch helpers
  75  */
  76 #ifdef CONFIG_USE_GENERIC_SMP_HELPERS
  77 void generic_smp_call_function_single_interrupt(void);
  78 void generic_smp_call_function_interrupt(void);
  79 void ipi_call_lock(void);
  80 void ipi_call_unlock(void);
  81 void ipi_call_lock_irq(void);
  82 void ipi_call_unlock_irq(void);
  83 #endif
  84
  85 /*
  86  * Call a function on all processors
  87  */
  88 int on_each_cpu(void (*func) (void *info), void *info, int wait);
  89
  90 #define MSG_ALL_BUT_SELF        0x8000  /* Assume <32768 CPU's */
  91 #define MSG_ALL                 0x8001
  92
  93 #define MSG_INVALIDATE_TLB      0x0001  /* Remote processor TLB invalidate */
  94 #define MSG_STOP_CPU            0x0002  /* Sent to shut down slave CPU's
  95                                          * when rebooting
  96                                          */
  97 #define MSG_RESCHEDULE          0x0003  /* Reschedule request from master CPU*/
  98 #define MSG_CALL_FUNCTION       0x0004  /* Call function on all other CPUs */
  99
 100 /*
 101  * Mark the boot cpu "online" so that it can call console drivers in
 102  * printk() and can access its per-cpu storage.
 103  */
 104 void smp_prepare_boot_cpu(void);
 105
 106 extern unsigned int setup_max_cpus;
 107
 108 #else /* !SMP */
 109
 110 /*
 111  *      These macros fold the SMP functionality into a single CPU system
 112  */
 113 #define raw_smp_processor_id()                  0
 114 static inline int up_smp_call_function(void (*func)(void *), void *info)
 115 {
 116         return 0;
 117 }
 118 #define smp_call_function(func, info, wait) \
 119                         (up_smp_call_function(func, info))
 120 #define on_each_cpu(func,info,wait)             \
 121         ({                                      \
 122                 local_irq_disable();            \
 123                 func(info);                     \
 124                 local_irq_enable();             \
 125                 0;                              \
 126         })
 127 static inline void smp_send_reschedule(int cpu) { }
 128 #define num_booting_cpus()                      1
 129 #define smp_prepare_boot_cpu()                  do {} while (0)
 130 #define smp_call_function_single(cpuid, func, info, wait) \
 131 ({ \
 132         WARN_ON(cpuid != 0);    \
 133         local_irq_disable();    \
 134         (func)(info);           \
 135         local_irq_enable();     \
 136         0;                      \
 137 })
 138 #define smp_call_function_mask(mask, func, info, wait) \
 139                         (up_smp_call_function(func, info))
 140 static inline void init_call_single_data(void)
 141 {
 142 }
 143 #endif /* !SMP */
 144
 145 /*
 146  * smp_processor_id(): get the current CPU ID.
 147  *
 148  * if DEBUG_PREEMPT is enabled the we check whether it is
 149  * used in a preemption-safe way. (smp_processor_id() is safe
 150  * if it's used in a preemption-off critical section, or in
 151  * a thread that is bound to the current CPU.)
 152  *
 153  * NOTE: raw_smp_processor_id() is for internal use only
 154  * (smp_processor_id() is the preferred variant), but in rare
 155  * instances it might also be used to turn off false positives
 156  * (i.e. smp_processor_id() use that the debugging code reports but
 157  * which use for some reason is legal). Don't use this to hack around
 158  * the warning message, as your code might not work under PREEMPT.
 159  */
 160 #ifdef CONFIG_DEBUG_PREEMPT
 161   extern unsigned int debug_smp_processor_id(void);
 162 # define smp_processor_id() debug_smp_processor_id()
 163 #else
 164 # define smp_processor_id() raw_smp_processor_id()
 165 #endif
 166
 167 #define get_cpu()               ({ preempt_disable(); smp_processor_id(); })
 168 #define put_cpu()               preempt_enable()
 169 #define put_cpu_no_resched()    preempt_enable_no_resched()
 170
 171 void smp_setup_processor_id(void);
 172
 173 #endif /* __LINUX_SMP_H */