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 typedef void (*smp_call_func_t)(void *info);
  17 struct call_single_data {
  18         struct list_head list;
  19         smp_call_func_t func;
  20         void *info;
  21         u16 flags;
  22         u16 priv;
  23 };
  24
  25 /* total number of cpus in this system (may exceed NR_CPUS) */
  26 extern unsigned int total_cpus;
  27
  28 int smp_call_function_single(int cpuid, smp_call_func_t func, void *info,
  29                              int wait);
  30
  31 #ifdef CONFIG_SMP
  32
  33 #include <linux/preempt.h>
  34 #include <linux/kernel.h>
  35 #include <linux/compiler.h>
  36 #include <linux/thread_info.h>
  37 #include <asm/smp.h>
  38
  39 /*
  40  * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
  41  * (defined in asm header):
  42  */
  43
  44 /*
  45  * stops all CPUs but the current one:
  46  */
  47 extern void smp_send_stop(void);
  48
  49 /*
  50  * sends a 'reschedule' event to another CPU:
  51  */
  52 extern void smp_send_reschedule(int cpu);
  53
  54
  55 /*
  56  * Prepare machine for booting other CPUs.
  57  */
  58 extern void smp_prepare_cpus(unsigned int max_cpus);
  59
  60 /*
  61  * Bring a CPU up
  62  */
  63 extern int __cpu_up(unsigned int cpunum);
  64
  65 /*
  66  * Final polishing of CPUs
  67  */
  68 extern void smp_cpus_done(unsigned int max_cpus);
  69
  70 /*
  71  * Call a function on all other processors
  72  */
  73 int smp_call_function(smp_call_func_t func, void *info, int wait);
  74 void smp_call_function_many(const struct cpumask *mask,
  75                             smp_call_func_t func, void *info, bool wait);
  76
  77 void __smp_call_function_single(int cpuid, struct call_single_data *data,
  78                                 int wait);
  79
  80 int smp_call_function_any(const struct cpumask *mask,
  81                           smp_call_func_t func, void *info, int wait);
  82
  83 /*
  84  * Generic and arch helpers
  85  */
  86 #ifdef CONFIG_USE_GENERIC_SMP_HELPERS
  87 void generic_smp_call_function_single_interrupt(void);
  88 void generic_smp_call_function_interrupt(void);
  89 void ipi_call_lock(void);
  90 void ipi_call_unlock(void);
  91 void ipi_call_lock_irq(void);
  92 void ipi_call_unlock_irq(void);
  93 #endif
  94
  95 /*
  96  * Call a function on all processors
  97  */
  98 int on_each_cpu(smp_call_func_t func, void *info, int wait);
  99
 100 #define MSG_ALL_BUT_SELF        0x8000  /* Assume <32768 CPU's */
 101 #define MSG_ALL                 0x8001
 102
 103 #define MSG_INVALIDATE_TLB      0x0001  /* Remote processor TLB invalidate */
 104 #define MSG_STOP_CPU            0x0002  /* Sent to shut down slave CPU's
 105                                          * when rebooting
 106                                          */
 107 #define MSG_RESCHEDULE          0x0003  /* Reschedule request from master CPU*/
 108 #define MSG_CALL_FUNCTION       0x0004  /* Call function on all other CPUs */
 109
 110 /*
 111  * Mark the boot cpu "online" so that it can call console drivers in
 112  * printk() and can access its per-cpu storage.
 113  */
 114 void smp_prepare_boot_cpu(void);
 115
 116 extern unsigned int setup_max_cpus;
 117 extern void __init setup_nr_cpu_ids(void);
 118 extern void __init smp_init(void);
 119
 120 #else /* !SMP */
 121
 122 static inline void smp_send_stop(void) { }
 123
 124 /*
 125  *      These macros fold the SMP functionality into a single CPU system
 126  */
 127 #define raw_smp_processor_id()                  0
 128 static inline int up_smp_call_function(smp_call_func_t func, void *info)
 129 {
 130         return 0;
 131 }
 132 #define smp_call_function(func, info, wait) \
 133                         (up_smp_call_function(func, info))
 134 #define on_each_cpu(func,info,wait)             \
 135         ({                                      \
 136                 local_irq_disable();            \
 137                 func(info);                     \
 138                 local_irq_enable();             \
 139                 0;                              \
 140         })
 141 static inline void smp_send_reschedule(int cpu) { }
 142 #define num_booting_cpus()                      1
 143 #define smp_prepare_boot_cpu()                  do {} while (0)
 144 #define smp_call_function_many(mask, func, info, wait) \
 145                         (up_smp_call_function(func, info))
 146 static inline void init_call_single_data(void) { }
 147
 148 static inline int
 149 smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
 150                       void *info, int wait)
 151 {
 152         return smp_call_function_single(0, func, info, wait);
 153 }
 154
 155 #endif /* !SMP */
 156
 157 /*
 158  * smp_processor_id(): get the current CPU ID.
 159  *
 160  * if DEBUG_PREEMPT is enabled then we check whether it is
 161  * used in a preemption-safe way. (smp_processor_id() is safe
 162  * if it's used in a preemption-off critical section, or in
 163  * a thread that is bound to the current CPU.)
 164  *
 165  * NOTE: raw_smp_processor_id() is for internal use only
 166  * (smp_processor_id() is the preferred variant), but in rare
 167  * instances it might also be used to turn off false positives
 168  * (i.e. smp_processor_id() use that the debugging code reports but
 169  * which use for some reason is legal). Don't use this to hack around
 170  * the warning message, as your code might not work under PREEMPT.
 171  */
 172 #ifdef CONFIG_DEBUG_PREEMPT
 173   extern unsigned int debug_smp_processor_id(void);
 174 # define smp_processor_id() debug_smp_processor_id()
 175 #else
 176 # define smp_processor_id() raw_smp_processor_id()
 177 #endif
 178
 179 #define get_cpu()               ({ preempt_disable(); smp_processor_id(); })
 180 #define put_cpu()               preempt_enable()
 181
 182 /*
 183  * Callback to arch code if there's nosmp or maxcpus=0 on the
 184  * boot command line:
 185  */
 186 extern void arch_disable_smp_support(void);
 187
 188 void smp_setup_processor_id(void);
 189
 190 #endif /* __LINUX_SMP_H */