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 #include <linux/init.h>
  14 #include <linux/llist.h>
  15
  16 typedef void (*smp_call_func_t)(void *info);
  17 struct call_single_data {
  18         struct llist_node llist;
  19         smp_call_func_t func;
  20         void *info;
  21         unsigned int flags;
  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, smp_call_func_t func, void *info,
  28                              int wait);
  29
  30 /*
  31  * Call a function on all processors
  32  */
  33 int on_each_cpu(smp_call_func_t func, void *info, int wait);
  34
  35 /*
  36  * Call a function on processors specified by mask, which might include
  37  * the local one.
  38  */
  39 void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func,
  40                 void *info, bool wait);
  41
  42 /*
  43  * Call a function on each processor for which the supplied function
  44  * cond_func returns a positive value. This may include the local
  45  * processor.
  46  */
  47 void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info),
  48                 smp_call_func_t func, void *info, bool wait,
  49                 gfp_t gfp_flags);
  50
  51 int smp_call_function_single_async(int cpu, struct call_single_data *csd);
  52
  53 #ifdef CONFIG_SMP
  54
  55 #include <linux/preempt.h>
  56 #include <linux/kernel.h>
  57 #include <linux/compiler.h>
  58 #include <linux/thread_info.h>
  59 #include <asm/smp.h>
  60
  61 /*
  62  * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
  63  * (defined in asm header):
  64  */
  65
  66 /*
  67  * stops all CPUs but the current one:
  68  */
  69 extern void smp_send_stop(void);
  70
  71 /*
  72  * sends a 'reschedule' event to another CPU:
  73  */
  74 extern void smp_send_reschedule(int cpu);
  75
  76
  77 /*
  78  * Prepare machine for booting other CPUs.
  79  */
  80 extern void smp_prepare_cpus(unsigned int max_cpus);
  81
  82 /*
  83  * Bring a CPU up
  84  */
  85 extern int __cpu_up(unsigned int cpunum, struct task_struct *tidle);
  86
  87 /*
  88  * Final polishing of CPUs
  89  */
  90 extern void smp_cpus_done(unsigned int max_cpus);
  91
  92 /*
  93  * Call a function on all other processors
  94  */
  95 int smp_call_function(smp_call_func_t func, void *info, int wait);
  96 void smp_call_function_many(const struct cpumask *mask,
  97                             smp_call_func_t func, void *info, bool wait);
  98
  99 int smp_call_function_any(const struct cpumask *mask,
 100                           smp_call_func_t func, void *info, int wait);
 101
 102 void kick_all_cpus_sync(void);
 103 void wake_up_all_idle_cpus(void);
 104
 105 /*
 106  * Generic and arch helpers
 107  */
 108 void __init call_function_init(void);
 109 void generic_smp_call_function_single_interrupt(void);
 110 #define generic_smp_call_function_interrupt \
 111         generic_smp_call_function_single_interrupt
 112
 113 /*
 114  * Mark the boot cpu "online" so that it can call console drivers in
 115  * printk() and can access its per-cpu storage.
 116  */
 117 void smp_prepare_boot_cpu(void);
 118
 119 extern unsigned int setup_max_cpus;
 120 extern void __init setup_nr_cpu_ids(void);
 121 extern void __init smp_init(void);
 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(smp_call_func_t func, void *info)
 132 {
 133         return 0;
 134 }
 135 #define smp_call_function(func, info, wait) \
 136                         (up_smp_call_function(func, info))
 137
 138 static inline void smp_send_reschedule(int cpu) { }
 139 #define smp_prepare_boot_cpu()                  do {} while (0)
 140 #define smp_call_function_many(mask, func, info, wait) \
 141                         (up_smp_call_function(func, info))
 142 static inline void call_function_init(void) { }
 143
 144 static inline int
 145 smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
 146                       void *info, int wait)
 147 {
 148         return smp_call_function_single(0, func, info, wait);
 149 }
 150
 151 static inline void kick_all_cpus_sync(void) {  }
 152 static inline void wake_up_all_idle_cpus(void) {  }
 153
 154 #ifdef CONFIG_UP_LATE_INIT
 155 extern void __init up_late_init(void);
 156 static inline void smp_init(void) { up_late_init(); }
 157 #else
 158 static inline void smp_init(void) { }
 159 #endif
 160
 161 #endif /* !SMP */
 162
 163 /*
 164  * smp_processor_id(): get the current CPU ID.
 165  *
 166  * if DEBUG_PREEMPT is enabled then we check whether it is
 167  * used in a preemption-safe way. (smp_processor_id() is safe
 168  * if it's used in a preemption-off critical section, or in
 169  * a thread that is bound to the current CPU.)
 170  *
 171  * NOTE: raw_smp_processor_id() is for internal use only
 172  * (smp_processor_id() is the preferred variant), but in rare
 173  * instances it might also be used to turn off false positives
 174  * (i.e. smp_processor_id() use that the debugging code reports but
 175  * which use for some reason is legal). Don't use this to hack around
 176  * the warning message, as your code might not work under PREEMPT.
 177  */
 178 #ifdef CONFIG_DEBUG_PREEMPT
 179   extern unsigned int debug_smp_processor_id(void);
 180 # define smp_processor_id() debug_smp_processor_id()
 181 #else
 182 # define smp_processor_id() raw_smp_processor_id()
 183 #endif
 184
 185 #define get_cpu()               ({ preempt_disable(); smp_processor_id(); })
 186 #define put_cpu()               preempt_enable()
 187
 188 /*
 189  * Callback to arch code if there's nosmp or maxcpus=0 on the
 190  * boot command line:
 191  */
 192 extern void arch_disable_smp_support(void);
 193
 194 extern void arch_enable_nonboot_cpus_begin(void);
 195 extern void arch_enable_nonboot_cpus_end(void);
 196
 197 void smp_setup_processor_id(void);
 198
 199 /* SMP core functions */
 200 int smpcfd_prepare_cpu(unsigned int cpu);
 201 int smpcfd_dead_cpu(unsigned int cpu);
 202 int smpcfd_dying_cpu(unsigned int cpu);
 203
 204 #endif /* __LINUX_SMP_H */