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