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