LXR linux/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
  14extern void cpu_idle(void);
  15
  16struct 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) */
  25extern unsigned int total_cpus;
  26
  27int 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 */
  46extern void smp_send_stop(void);
  47
  48/*
  49 * sends a 'reschedule' event to another CPU:
  50 */
  51extern void smp_send_reschedule(int cpu);
  52
  53
  54/*
  55 * Prepare machine for booting other CPUs.
  56 */
  57extern void smp_prepare_cpus(unsigned int max_cpus);
  58
  59/*
  60 * Bring a CPU up
  61 */
  62extern int __cpu_up(unsigned int cpunum);
  63
  64/*
  65 * Final polishing of CPUs
  66 */
  67extern void smp_cpus_done(unsigned int max_cpus);
  68
  69/*
  70 * Call a function on all other processors
  71 */
  72int smp_call_function(void(*func)(void *info), void *info, int wait);
  73void smp_call_function_many(const struct cpumask *mask,
  74                            void (*func)(void *info), void *info, bool wait);
  75
  76void __smp_call_function_single(int cpuid, struct call_single_data *data,
  77                                int wait);
  78
  79int smp_call_function_any(const struct cpumask *mask,
  80                          void (*func)(void *info), void *info, int wait);
  81
  82/*
  83 * Generic and arch helpers
  84 */
  85#ifdef CONFIG_USE_GENERIC_SMP_HELPERS
  86void generic_smp_call_function_single_interrupt(void);
  87void generic_smp_call_function_interrupt(void);
  88void ipi_call_lock(void);
  89void ipi_call_unlock(void);
  90void ipi_call_lock_irq(void);
  91void ipi_call_unlock_irq(void);
  92#endif
  93
  94/*
  95 * Call a function on all processors
  96 */
  97int on_each_cpu(void (*func) (void *info), void *info, int wait);
  98
  99#define MSG_ALL_BUT_SELF        0x8000  /* Assume <32768 CPU's */
 100#define MSG_ALL                 0x8001
 101
 102#define MSG_INVALIDATE_TLB      0x0001  /* Remote processor TLB invalidate */
 103#define MSG_STOP_CPU            0x0002  /* Sent to shut down slave CPU's
 104                                         * when rebooting
 105                                         */
 106#define MSG_RESCHEDULE          0x0003  /* Reschedule request from master CPU*/
 107#define MSG_CALL_FUNCTION       0x0004  /* Call function on all other CPUs */
 108
 109/*
 110 * Mark the boot cpu "online" so that it can call console drivers in
 111 * printk() and can access its per-cpu storage.
 112 */
 113void smp_prepare_boot_cpu(void);
 114
 115extern unsigned int setup_max_cpus;
 116
 117#else /* !SMP */
 118
 119static inline void smp_send_stop(void) { }
 120
 121/*
 122 *      These macros fold the SMP functionality into a single CPU system
 123 */
 124#define raw_smp_processor_id()                  0
 125static inline int up_smp_call_function(void (*func)(void *), void *info)
 126{
 127        return 0;
 128}
 129#define smp_call_function(func, info, wait) \
 130                        (up_smp_call_function(func, info))
 131#define on_each_cpu(func,info,wait)             \
 132        ({                                      \
 133                local_irq_disable();            \
 134                func(info);                     \
 135                local_irq_enable();             \
 136                0;                              \
 137        })
 138static inline void smp_send_reschedule(int cpu) { }
 139#define num_booting_cpus()                      1
 140#define smp_prepare_boot_cpu()                  do {} while (0)
 141#define smp_call_function_many(mask, func, info, wait) \
 142                        (up_smp_call_function(func, info))
 143static inline void init_call_single_data(void) { }
 144
 145static inline int
 146smp_call_function_any(const struct cpumask *mask, void (*func)(void *info),
 147                      void *info, int wait)
 148{
 149        return smp_call_function_single(0, func, info, wait);
 150}
 151
 152#endif /* !SMP */
 153
 154/*
 155 * smp_processor_id(): get the current CPU ID.
 156 *
 157 * if DEBUG_PREEMPT is enabled the we check whether it is
 158 * used in a preemption-safe way. (smp_processor_id() is safe
 159 * if it's used in a preemption-off critical section, or in
 160 * a thread that is bound to the current CPU.)
 161 *
 162 * NOTE: raw_smp_processor_id() is for internal use only
 163 * (smp_processor_id() is the preferred variant), but in rare
 164 * instances it might also be used to turn off false positives
 165 * (i.e. smp_processor_id() use that the debugging code reports but
 166 * which use for some reason is legal). Don't use this to hack around
 167 * the warning message, as your code might not work under PREEMPT.
 168 */
 169#ifdef CONFIG_DEBUG_PREEMPT
 170  extern unsigned int debug_smp_processor_id(void);
 171# define smp_processor_id() debug_smp_processor_id()
 172#else
 173# define smp_processor_id() raw_smp_processor_id()
 174#endif
 175
 176#define get_cpu()               ({ preempt_disable(); smp_processor_id(); })
 177#define put_cpu()               preempt_enable()
 178
 179/*
 180 * Callback to arch code if there's nosmp or maxcpus=0 on the
 181 * boot command line:
 182 */
 183extern void arch_disable_smp_support(void);
 184
 185void smp_setup_processor_id(void);
 186
 187#endif /* __LINUX_SMP_H */
 188