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 /* Deprecated: Use smp_call_function_many which takes a pointer to the mask. */
  77 static inline int
  78 smp_call_function_mask(cpumask_t mask, void(*func)(void *info), void *info,
  79                        int wait)
  80 {
  81         smp_call_function_many(&mask, func, info, wait);
  82         return 0;
  83 }
  84
  85 void __smp_call_function_single(int cpuid, struct call_single_data *data,
  86                                 int wait);
  87
  88 /*
  89  * Generic and arch helpers
  90  */
  91 #ifdef CONFIG_USE_GENERIC_SMP_HELPERS
  92 void generic_smp_call_function_single_interrupt(void);
  93 void generic_smp_call_function_interrupt(void);
  94 void ipi_call_lock(void);
  95 void ipi_call_unlock(void);
  96 void ipi_call_lock_irq(void);
  97 void ipi_call_unlock_irq(void);
  98 #endif
  99
 100 /*
 101  * Call a function on all processors
 102  */
 103 int on_each_cpu(void (*func) (void *info), void *info, int wait);
 104
 105 #define MSG_ALL_BUT_SELF        0x8000  /* Assume <32768 CPU's */
 106 #define MSG_ALL                 0x8001
 107
 108 #define MSG_INVALIDATE_TLB      0x0001  /* Remote processor TLB invalidate */
 109 #define MSG_STOP_CPU            0x0002  /* Sent to shut down slave CPU's
 110                                          * when rebooting
 111                                          */
 112 #define MSG_RESCHEDULE          0x0003  /* Reschedule request from master CPU*/
 113 #define MSG_CALL_FUNCTION       0x0004  /* Call function on all other CPUs */
 114
 115 /*
 116  * Mark the boot cpu "online" so that it can call console drivers in
 117  * printk() and can access its per-cpu storage.
 118  */
 119 void smp_prepare_boot_cpu(void);
 120
 121 extern unsigned int setup_max_cpus;
 122
 123 #else /* !SMP */
 124
 125 static inline void smp_send_stop(void) { }
 126
 127 /*
 128  *      These macros fold the SMP functionality into a single CPU system
 129  */
 130 #define raw_smp_processor_id()                  0
 131 static inline int up_smp_call_function(void (*func)(void *), void *info)
 132 {
 133         return 0;
 134 }
 135 #define smp_call_function(func, info, wait) \
 136                         (up_smp_call_function(func, info))
 137 #define on_each_cpu(func,info,wait)             \
 138         ({                                      \
 139                 local_irq_disable();            \
 140                 func(info);                     \
 141                 local_irq_enable();             \
 142                 0;                              \
 143         })
 144 static inline void smp_send_reschedule(int cpu) { }
 145 #define num_booting_cpus()                      1
 146 #define smp_prepare_boot_cpu()                  do {} while (0)
 147 #define smp_call_function_mask(mask, func, info, wait) \
 148                         (up_smp_call_function(func, info))
 149 #define smp_call_function_many(mask, func, info, wait) \
 150                         (up_smp_call_function(func, info))
 151 static inline void init_call_single_data(void)
 152 {
 153 }
 154 #endif /* !SMP */
 155
 156 /*
 157  * smp_processor_id(): get the current CPU ID.
 158  *
 159  * if DEBUG_PREEMPT is enabled the we check whether it is
 160  * used in a preemption-safe way. (smp_processor_id() is safe
 161  * if it's used in a preemption-off critical section, or in
 162  * a thread that is bound to the current CPU.)
 163  *
 164  * NOTE: raw_smp_processor_id() is for internal use only
 165  * (smp_processor_id() is the preferred variant), but in rare
 166  * instances it might also be used to turn off false positives
 167  * (i.e. smp_processor_id() use that the debugging code reports but
 168  * which use for some reason is legal). Don't use this to hack around
 169  * the warning message, as your code might not work under PREEMPT.
 170  */
 171 #ifdef CONFIG_DEBUG_PREEMPT
 172   extern unsigned int debug_smp_processor_id(void);
 173 # define smp_processor_id() debug_smp_processor_id()
 174 #else
 175 # define smp_processor_id() raw_smp_processor_id()
 176 #endif
 177
 178 #define get_cpu()               ({ preempt_disable(); smp_processor_id(); })
 179 #define put_cpu()               preempt_enable()
 180 #define put_cpu_no_resched()    preempt_enable_no_resched()
 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 */