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 /* total number of cpus in this system (may exceed NR_CPUS) */
  25 extern unsigned int total_cpus;
  26
  27 #ifdef CONFIG_SMP
  28
  29 #include <linux/preempt.h>
  30 #include <linux/kernel.h>
  31 #include <linux/compiler.h>
  32 #include <linux/thread_info.h>
  33 #include <asm/smp.h>
  34
  35 /*
  36  * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
  37  * (defined in asm header):
  38  */
  39
  40 /*
  41  * stops all CPUs but the current one:
  42  */
  43 extern void smp_send_stop(void);
  44
  45 /*
  46  * sends a 'reschedule' event to another CPU:
  47  */
  48 extern void smp_send_reschedule(int cpu);
  49
  50
  51 /*
  52  * Prepare machine for booting other CPUs.
  53  */
  54 extern void smp_prepare_cpus(unsigned int max_cpus);
  55
  56 /*
  57  * Bring a CPU up
  58  */
  59 extern int __cpu_up(unsigned int cpunum);
  60
  61 /*
  62  * Final polishing of CPUs
  63  */
  64 extern void smp_cpus_done(unsigned int max_cpus);
  65
  66 /*
  67  * Call a function on all other processors
  68  */
  69 int smp_call_function(void(*func)(void *info), void *info, int wait);
  70 /* Deprecated: use smp_call_function_many() which uses a cpumask ptr. */
  71 int smp_call_function_mask(cpumask_t mask, void(*func)(void *info), void *info,
  72                                 int wait);
  73
  74 static inline void smp_call_function_many(const struct cpumask *mask,
  75                                           void (*func)(void *info), void *info,
  76                                           int wait)
  77 {
  78         smp_call_function_mask(*mask, func, info, wait);
  79 }
  80
  81 int smp_call_function_single(int cpuid, void (*func) (void *info), void *info,
  82                                 int wait);
  83 void __smp_call_function_single(int cpuid, struct call_single_data *data);
  84
  85 /*
  86  * Generic and arch helpers
  87  */
  88 #ifdef CONFIG_USE_GENERIC_SMP_HELPERS
  89 void generic_smp_call_function_single_interrupt(void);
  90 void generic_smp_call_function_interrupt(void);
  91 void ipi_call_lock(void);
  92 void ipi_call_unlock(void);
  93 void ipi_call_lock_irq(void);
  94 void ipi_call_unlock_irq(void);
  95 #endif
  96
  97 /*
  98  * Call a function on all processors
  99  */
 100 int on_each_cpu(void (*func) (void *info), void *info, int wait);
 101
 102 #define MSG_ALL_BUT_SELF        0x8000  /* Assume <32768 CPU's */
 103 #define MSG_ALL                 0x8001
 104
 105 #define MSG_INVALIDATE_TLB      0x0001  /* Remote processor TLB invalidate */
 106 #define MSG_STOP_CPU            0x0002  /* Sent to shut down slave CPU's
 107                                          * when rebooting
 108                                          */
 109 #define MSG_RESCHEDULE          0x0003  /* Reschedule request from master CPU*/
 110 #define MSG_CALL_FUNCTION       0x0004  /* Call function on all other CPUs */
 111
 112 /*
 113  * Mark the boot cpu "online" so that it can call console drivers in
 114  * printk() and can access its per-cpu storage.
 115  */
 116 void smp_prepare_boot_cpu(void);
 117
 118 extern unsigned int setup_max_cpus;
 119
 120 #else /* !SMP */
 121
 122 /*
 123  *      These macros fold the SMP functionality into a single CPU system
 124  */
 125 #define raw_smp_processor_id()                  0
 126 static inline int up_smp_call_function(void (*func)(void *), void *info)
 127 {
 128         return 0;
 129 }
 130 #define smp_call_function(func, info, wait) \
 131                         (up_smp_call_function(func, info))
 132 #define on_each_cpu(func,info,wait)             \
 133         ({                                      \
 134                 local_irq_disable();            \
 135                 func(info);                     \
 136                 local_irq_enable();             \
 137                 0;                              \
 138         })
 139 static inline void smp_send_reschedule(int cpu) { }
 140 #define num_booting_cpus()                      1
 141 #define smp_prepare_boot_cpu()                  do {} while (0)
 142 #define smp_call_function_single(cpuid, func, info, wait) \
 143 ({ \
 144         WARN_ON(cpuid != 0);    \
 145         local_irq_disable();    \
 146         (func)(info);           \
 147         local_irq_enable();     \
 148         0;                      \
 149 })
 150 #define smp_call_function_mask(mask, func, info, wait) \
 151                         (up_smp_call_function(func, info))
 152 #define smp_call_function_many(mask, func, info, wait) \
 153                         (up_smp_call_function(func, info))
 154 static inline void init_call_single_data(void)
 155 {
 156 }
 157 #endif /* !SMP */
 158
 159 /*
 160  * smp_processor_id(): get the current CPU ID.
 161  *
 162  * if DEBUG_PREEMPT is enabled the we check whether it is
 163  * used in a preemption-safe way. (smp_processor_id() is safe
 164  * if it's used in a preemption-off critical section, or in
 165  * a thread that is bound to the current CPU.)
 166  *
 167  * NOTE: raw_smp_processor_id() is for internal use only
 168  * (smp_processor_id() is the preferred variant), but in rare
 169  * instances it might also be used to turn off false positives
 170  * (i.e. smp_processor_id() use that the debugging code reports but
 171  * which use for some reason is legal). Don't use this to hack around
 172  * the warning message, as your code might not work under PREEMPT.
 173  */
 174 #ifdef CONFIG_DEBUG_PREEMPT
 175   extern unsigned int debug_smp_processor_id(void);
 176 # define smp_processor_id() debug_smp_processor_id()
 177 #else
 178 # define smp_processor_id() raw_smp_processor_id()
 179 #endif
 180
 181 #define get_cpu()               ({ preempt_disable(); smp_processor_id(); })
 182 #define put_cpu()               preempt_enable()
 183 #define put_cpu_no_resched()    preempt_enable_no_resched()
 184
 185 void smp_setup_processor_id(void);
 186
 187 #endif /* __LINUX_SMP_H */