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/config.h>
  10
  11 #ifdef CONFIG_SMP
  12
  13 #include <linux/preempt.h>
  14 #include <linux/kernel.h>
  15 #include <linux/compiler.h>
  16 #include <linux/thread_info.h>
  17 #include <asm/smp.h>
  18 #include <asm/bug.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 FASTCALL(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 extern int smp_call_function (void (*func) (void *info), void *info,
  55                               int retry, int wait);
  56
  57 /*
  58  * Call a function on all processors
  59  */
  60 static inline int on_each_cpu(void (*func) (void *info), void *info,
  61                               int retry, int wait)
  62 {
  63         int ret = 0;
  64
  65         preempt_disable();
  66         ret = smp_call_function(func, info, retry, wait);
  67         func(info);
  68         preempt_enable();
  69         return ret;
  70 }
  71
  72 /*
  73  * True once the per process idle is forked
  74  */
  75 extern int smp_threads_ready;
  76
  77 #define MSG_ALL_BUT_SELF        0x8000  /* Assume <32768 CPU's */
  78 #define MSG_ALL                 0x8001
  79
  80 #define MSG_INVALIDATE_TLB      0x0001  /* Remote processor TLB invalidate */
  81 #define MSG_STOP_CPU            0x0002  /* Sent to shut down slave CPU's
  82                                          * when rebooting
  83                                          */
  84 #define MSG_RESCHEDULE          0x0003  /* Reschedule request from master CPU*/
  85 #define MSG_CALL_FUNCTION       0x0004  /* Call function on all other CPUs */
  86
  87 /*
  88  * Mark the boot cpu "online" so that it can call console drivers in
  89  * printk() and can access its per-cpu storage.
  90  */
  91 void smp_prepare_boot_cpu(void);
  92
  93 #else /* !SMP */
  94
  95 /*
  96  *      These macros fold the SMP functionality into a single CPU system
  97  */
  98
  99 #define smp_processor_id()                      0
 100 #define hard_smp_processor_id()                 0
 101 #define smp_threads_ready                       1
 102 #define smp_call_function(func,info,retry,wait) ({ 0; })
 103 #define on_each_cpu(func,info,retry,wait)       ({ func(info); 0; })
 104 static inline void smp_send_reschedule(int cpu) { }
 105 #define cpu_online_map                          1
 106 #define cpu_online(cpu)                         ({ BUG_ON((cpu) != 0); 1; })
 107 #define num_online_cpus()                       1
 108 #define num_booting_cpus()                      1
 109 #define cpu_possible(cpu)                       ({ BUG_ON((cpu) != 0); 1; })
 110 #define smp_prepare_boot_cpu()                  do {} while (0)
 111
 112 #endif /* !SMP */
 113
 114 #define get_cpu()               ({ preempt_disable(); smp_processor_id(); })
 115 #define put_cpu()               preempt_enable()
 116 #define put_cpu_no_resched()    preempt_enable_no_resched()
 117
 118 #endif /* __LINUX_SMP_H */