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/list.h>
  11 #include <linux/cpumask.h>
  12
  13 extern void cpu_idle(void);
  14
  15 struct call_single_data {
  16         struct list_head list;
  17         void (*func) (void *info);
  18         void *info;
  19         unsigned int flags;
  20 };
  21
  22 #ifdef CONFIG_SMP
  23
  24 #include <linux/preempt.h>
  25 #include <linux/kernel.h>
  26 #include <linux/compiler.h>
  27 #include <linux/thread_info.h>
  28 #include <asm/smp.h>
  29
  30 /*
  31  * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
  32  * (defined in asm header):
  33  */
  34
  35 /*
  36  * stops all CPUs but the current one:
  37  */
  38 extern void smp_send_stop(void);
  39
  40 /*
  41  * sends a 'reschedule' event to another CPU:
  42  */
  43 extern void smp_send_reschedule(int cpu);
  44
  45
  46 /*
  47  * Prepare machine for booting other CPUs.
  48  */
  49 extern void smp_prepare_cpus(unsigned int max_cpus);
  50
  51 /*
  52  * Bring a CPU up
  53  */
  54 extern int __cpu_up(unsigned int cpunum);
  55
  56 /*
  57  * Final polishing of CPUs
  58  */
  59 extern void smp_cpus_done(unsigned int max_cpus);
  60
  61 /*
  62  * Call a function on all other processors
  63  */
  64 int smp_call_function(void(*func)(void *info), void *info, int wait);
  65 int smp_call_function_mask(cpumask_t mask, void(*func)(void *info), void *info,
  66                                 int wait);
  67 int smp_call_function_single(int cpuid, void (*func) (void *info), void *info,
  68                                 int wait);
  69 void __smp_call_function_single(int cpuid, struct call_single_data *data);
  70
  71 /*
  72  * Generic and arch helpers
  73  */
  74 #ifdef CONFIG_USE_GENERIC_SMP_HELPERS
  75 void generic_smp_call_function_single_interrupt(void);
  76 void generic_smp_call_function_interrupt(void);
  77 void init_call_single_data(void);
  78 void ipi_call_lock(void);
  79 void ipi_call_unlock(void);
  80 void ipi_call_lock_irq(void);
  81 void ipi_call_unlock_irq(void);
  82 #else
  83 static inline void init_call_single_data(void)
  84 {
  85 }
  86 #endif
  87
  88 /*
  89  * Call a function on all processors
  90  */
  91 int on_each_cpu(void (*func) (void *info), void *info, int wait);
  92
  93 #define MSG_ALL_BUT_SELF        0x8000  /* Assume <32768 CPU's */
  94 #define MSG_ALL                 0x8001
  95
  96 #define MSG_INVALIDATE_TLB      0x0001  /* Remote processor TLB invalidate */
  97 #define MSG_STOP_CPU            0x0002  /* Sent to shut down slave CPU's
  98                                          * when rebooting
  99                                          */
 100 #define MSG_RESCHEDULE          0x0003  /* Reschedule request from master CPU*/
 101 #define MSG_CALL_FUNCTION       0x0004  /* Call function on all other CPUs */
 102
 103 /*
 104  * Mark the boot cpu "online" so that it can call console drivers in
 105  * printk() and can access its per-cpu storage.
 106  */
 107 void smp_prepare_boot_cpu(void);
 108
 109 extern unsigned int setup_max_cpus;
 110
 111 #else /* !SMP */
 112
 113 /*
 114  *      These macros fold the SMP functionality into a single CPU system
 115  */
 116 #define raw_smp_processor_id()                  0
 117 static inline int up_smp_call_function(void (*func)(void *), void *info)
 118 {
 119         return 0;
 120 }
 121 #define smp_call_function(func, info, wait) \
 122                         (up_smp_call_function(func, info))
 123 #define on_each_cpu(func,info,wait)             \
 124         ({                                      \
 125                 local_irq_disable();            \
 126                 func(info);                     \
 127                 local_irq_enable();             \
 128                 0;                              \
 129         })
 130 static inline void smp_send_reschedule(int cpu) { }
 131 #define num_booting_cpus()                      1
 132 #define smp_prepare_boot_cpu()                  do {} while (0)
 133 #define smp_call_function_single(cpuid, func, info, wait) \
 134 ({ \
 135         WARN_ON(cpuid != 0);    \
 136         local_irq_disable();    \
 137         (func)(info);           \
 138         local_irq_enable();     \
 139         0;                      \
 140 })
 141 #define smp_call_function_mask(mask, func, info, wait) \
 142                         (up_smp_call_function(func, info))
 143 static inline void init_call_single_data(void)
 144 {
 145 }
 146 #endif /* !SMP */
 147
 148 /*
 149  * smp_processor_id(): get the current CPU ID.
 150  *
 151  * if DEBUG_PREEMPT is enabled the we check whether it is
 152  * used in a preemption-safe way. (smp_processor_id() is safe
 153  * if it's used in a preemption-off critical section, or in
 154  * a thread that is bound to the current CPU.)
 155  *
 156  * NOTE: raw_smp_processor_id() is for internal use only
 157  * (smp_processor_id() is the preferred variant), but in rare
 158  * instances it might also be used to turn off false positives
 159  * (i.e. smp_processor_id() use that the debugging code reports but
 160  * which use for some reason is legal). Don't use this to hack around
 161  * the warning message, as your code might not work under PREEMPT.
 162  */
 163 #ifdef CONFIG_DEBUG_PREEMPT
 164   extern unsigned int debug_smp_processor_id(void);
 165 # define smp_processor_id() debug_smp_processor_id()
 166 #else
 167 # define smp_processor_id() raw_smp_processor_id()
 168 #endif
 169
 170 #define get_cpu()               ({ preempt_disable(); smp_processor_id(); })
 171 #define put_cpu()               preempt_enable()
 172 #define put_cpu_no_resched()    preempt_enable_no_resched()
 173
 174 void smp_setup_processor_id(void);
 175
 176 #endif /* __LINUX_SMP_H */