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/irqflags.h>
  15
  16 extern void cpu_idle(void);
  17
  18 typedef void (*smp_call_func_t)(void *info);
  19 struct call_single_data {
  20         struct list_head list;
  21         smp_call_func_t func;
  22         void *info;
  23         cpumask_var_t cpumask;
  24         u16 flags;
  25         u16 priv;
  26 };
  27
  28 /* total number of cpus in this system (may exceed NR_CPUS) */
  29 extern unsigned int total_cpus;
  30
  31 int smp_call_function_single(int cpuid, smp_call_func_t func, void *info,
  32                              int wait);
  33
  34 int mtk_smp_call_function_single(int cpuid, smp_call_func_t func, void *info, int wait);
  35
  36 #ifdef CONFIG_SMP
  37
  38 #include <linux/preempt.h>
  39 #include <linux/kernel.h>
  40 #include <linux/compiler.h>
  41 #include <linux/thread_info.h>
  42 #include <asm/smp.h>
  43
  44 /*
  45  * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
  46  * (defined in asm header):
  47  */
  48
  49 /*
  50  * stops all CPUs but the current one:
  51  */
  52 extern void smp_send_stop(void);
  53
  54 /*
  55  * sends a 'reschedule' event to another CPU:
  56  */
  57 extern void smp_send_reschedule(int cpu);
  58
  59
  60 /*
  61  * Prepare machine for booting other CPUs.
  62  */
  63 extern void smp_prepare_cpus(unsigned int max_cpus);
  64
  65 /*
  66  * Bring a CPU up
  67  */
  68 extern int __cpu_up(unsigned int cpunum, struct task_struct *tidle);
  69
  70 /*
  71  * Final polishing of CPUs
  72  */
  73 extern void smp_cpus_done(unsigned int max_cpus);
  74
  75 /*
  76  * Call a function on all other processors
  77  */
  78 int smp_call_function(smp_call_func_t func, void *info, int wait);
  79 void smp_call_function_many(const struct cpumask *mask,
  80                             smp_call_func_t func, void *info, bool wait);
  81
  82 void __smp_call_function_single(int cpuid, struct call_single_data *data,
  83                                 int wait);
  84
  85 int smp_call_function_any(const struct cpumask *mask,
  86                           smp_call_func_t func, void *info, int wait);
  87
  88 void kick_all_cpus_sync(void);
  89
  90 /*
  91  * Generic and arch helpers
  92  */
  93 #ifdef CONFIG_USE_GENERIC_SMP_HELPERS
  94 void __init call_function_init(void);
  95 void generic_smp_call_function_single_interrupt(void);
  96 #define generic_smp_call_function_interrupt \
  97         generic_smp_call_function_single_interrupt
  98 #else
  99 static inline void call_function_init(void) { }
 100 #endif
 101
 102 /*
 103  * Call a function on all processors
 104  */
 105 int on_each_cpu(smp_call_func_t func, void *info, int wait);
 106
 107 /*
 108  * Call a function on processors specified by mask, which might include
 109  * the local one.
 110  */
 111 void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func,
 112                 void *info, bool wait);
 113
 114 /*
 115  * Call a function on each processor for which the supplied function
 116  * cond_func returns a positive value. This may include the local
 117  * processor.
 118  */
 119 void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info),
 120                 smp_call_func_t func, void *info, bool wait,
 121                 gfp_t gfp_flags);
 122
 123 /*
 124  * Mark the boot cpu "online" so that it can call console drivers in
 125  * printk() and can access its per-cpu storage.
 126  */
 127 void smp_prepare_boot_cpu(void);
 128
 129 extern unsigned int setup_max_cpus;
 130 extern void __init setup_nr_cpu_ids(void);
 131 extern void __init smp_init(void);
 132
 133 #else /* !SMP */
 134
 135 static inline void smp_send_stop(void) { }
 136
 137 /*
 138  *      These macros fold the SMP functionality into a single CPU system
 139  */
 140 #define raw_smp_processor_id()                  0
 141 static inline int up_smp_call_function(smp_call_func_t func, void *info)
 142 {
 143         return 0;
 144 }
 145 #define smp_call_function(func, info, wait) \
 146                         (up_smp_call_function(func, info))
 147
 148 static inline int on_each_cpu(smp_call_func_t func, void *info, int wait)
 149 {
 150         unsigned long flags;
 151
 152         local_irq_save(flags);
 153         func(info);
 154         local_irq_restore(flags);
 155         return 0;
 156 }
 157
 158 /*
 159  * Note we still need to test the mask even for UP
 160  * because we actually can get an empty mask from
 161  * code that on SMP might call us without the local
 162  * CPU in the mask.
 163  */
 164 #define on_each_cpu_mask(mask, func, info, wait) \
 165         do {                                            \
 166                 if (cpumask_test_cpu(0, (mask))) {      \
 167                         local_irq_disable();            \
 168                         (func)(info);                   \
 169                         local_irq_enable();             \
 170                 }                                       \
 171         } while (0)
 172 /*
 173  * Preemption is disabled here to make sure the cond_func is called under the
 174  * same condtions in UP and SMP.
 175  */
 176 #define on_each_cpu_cond(cond_func, func, info, wait, gfp_flags)\
 177         do {                                                    \
 178                 void *__info = (info);                          \
 179                 preempt_disable();                              \
 180                 if ((cond_func)(0, __info)) {                   \
 181                         local_irq_disable();                    \
 182                         (func)(__info);                         \
 183                         local_irq_enable();                     \
 184                 }                                               \
 185                 preempt_enable();                               \
 186         } while (0)
 187
 188 static inline void smp_send_reschedule(int cpu) { }
 189 #define smp_prepare_boot_cpu()                  do {} while (0)
 190 #define smp_call_function_many(mask, func, info, wait) \
 191                         (up_smp_call_function(func, info))
 192 static inline void call_function_init(void) { }
 193
 194 static inline int
 195 smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
 196                       void *info, int wait)
 197 {
 198         return smp_call_function_single(0, func, info, wait);
 199 }
 200
 201 static inline void kick_all_cpus_sync(void) {  }
 202
 203 #endif /* !SMP */
 204
 205 /*
 206  * smp_processor_id(): get the current CPU ID.
 207  *
 208  * if DEBUG_PREEMPT is enabled then we check whether it is
 209  * used in a preemption-safe way. (smp_processor_id() is safe
 210  * if it's used in a preemption-off critical section, or in
 211  * a thread that is bound to the current CPU.)
 212  *
 213  * NOTE: raw_smp_processor_id() is for internal use only
 214  * (smp_processor_id() is the preferred variant), but in rare
 215  * instances it might also be used to turn off false positives
 216  * (i.e. smp_processor_id() use that the debugging code reports but
 217  * which use for some reason is legal). Don't use this to hack around
 218  * the warning message, as your code might not work under PREEMPT.
 219  */
 220 #ifdef CONFIG_DEBUG_PREEMPT
 221   extern unsigned int debug_smp_processor_id(void);
 222 # define smp_processor_id() debug_smp_processor_id()
 223 #else
 224 # define smp_processor_id() raw_smp_processor_id()
 225 #endif
 226
 227 #define get_cpu()               ({ preempt_disable(); smp_processor_id(); })
 228 #define put_cpu()               preempt_enable()
 229
 230 /*
 231  * Callback to arch code if there's nosmp or maxcpus=0 on the
 232  * boot command line:
 233  */
 234 extern void arch_disable_smp_support(void);
 235
 236 void smp_setup_processor_id(void);
 237
 238 #endif /* __LINUX_SMP_H */