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 /*
  80  * Generic and arch helpers
  81  */
  82 #ifdef CONFIG_USE_GENERIC_SMP_HELPERS
  83 void generic_smp_call_function_single_interrupt(void);
  84 void generic_smp_call_function_interrupt(void);
  85 void ipi_call_lock(void);
  86 void ipi_call_unlock(void);
  87 void ipi_call_lock_irq(void);
  88 void ipi_call_unlock_irq(void);
  89 #endif
  90
  91 /*
  92  * Call a function on all processors
  93  */
  94 int on_each_cpu(void (*func) (void *info), void *info, int wait);
  95
  96 #define MSG_ALL_BUT_SELF        0x8000  /* Assume <32768 CPU's */
  97 #define MSG_ALL                 0x8001
  98
  99 #define MSG_INVALIDATE_TLB      0x0001  /* Remote processor TLB invalidate */
 100 #define MSG_STOP_CPU            0x0002  /* Sent to shut down slave CPU's
 101                                          * when rebooting
 102                                          */
 103 #define MSG_RESCHEDULE          0x0003  /* Reschedule request from master CPU*/
 104 #define MSG_CALL_FUNCTION       0x0004  /* Call function on all other CPUs */
 105
 106 /*
 107  * Mark the boot cpu "online" so that it can call console drivers in
 108  * printk() and can access its per-cpu storage.
 109  */
 110 void smp_prepare_boot_cpu(void);
 111
 112 extern unsigned int setup_max_cpus;
 113
 114 #else /* !SMP */
 115
 116 static inline void smp_send_stop(void) { }
 117
 118 /*
 119  *      These macros fold the SMP functionality into a single CPU system
 120  */
 121 #define raw_smp_processor_id()                  0
 122 static inline int up_smp_call_function(void (*func)(void *), void *info)
 123 {
 124         return 0;
 125 }
 126 #define smp_call_function(func, info, wait) \
 127                         (up_smp_call_function(func, info))
 128 #define on_each_cpu(func,info,wait)             \
 129         ({                                      \
 130                 local_irq_disable();            \
 131                 func(info);                     \
 132                 local_irq_enable();             \
 133                 0;                              \
 134         })
 135 static inline void smp_send_reschedule(int cpu) { }
 136 #define num_booting_cpus()                      1
 137 #define smp_prepare_boot_cpu()                  do {} while (0)
 138 #define smp_call_function_many(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
 170 /*
 171  * Callback to arch code if there's nosmp or maxcpus=0 on the
 172  * boot command line:
 173  */
 174 extern void arch_disable_smp_support(void);
 175
 176 void smp_setup_processor_id(void);
 177
 178 #endif /* __LINUX_SMP_H */