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