LXR linux/kernel/up.c

   1/*
   2 * Uniprocessor-only support functions.  The counterpart to kernel/smp.c
   3 */
   4
   5#include <linux/interrupt.h>
   6#include <linux/kernel.h>
   7#include <linux/export.h>
   8#include <linux/smp.h>
   9
  10int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
  11                                int wait)
  12{
  13        unsigned long flags;
  14
  15        WARN_ON(cpu != 0);
  16
  17        local_irq_save(flags);
  18        func(info);
  19        local_irq_restore(flags);
  20
  21        return 0;
  22}
  23EXPORT_SYMBOL(smp_call_function_single);
  24
  25int smp_call_function_single_async(int cpu, struct call_single_data *csd)
  26{
  27        unsigned long flags;
  28
  29        local_irq_save(flags);
  30        csd->func(csd->info);
  31        local_irq_restore(flags);
  32        return 0;
  33}
  34EXPORT_SYMBOL(smp_call_function_single_async);
  35
  36int on_each_cpu(smp_call_func_t func, void *info, int wait)
  37{
  38        unsigned long flags;
  39
  40        local_irq_save(flags);
  41        func(info);
  42        local_irq_restore(flags);
  43        return 0;
  44}
  45EXPORT_SYMBOL(on_each_cpu);
  46
  47/*
  48 * Note we still need to test the mask even for UP
  49 * because we actually can get an empty mask from
  50 * code that on SMP might call us without the local
  51 * CPU in the mask.
  52 */
  53void on_each_cpu_mask(const struct cpumask *mask,
  54                      smp_call_func_t func, void *info, bool wait)
  55{
  56        unsigned long flags;
  57
  58        if (cpumask_test_cpu(0, mask)) {
  59                local_irq_save(flags);
  60                func(info);
  61                local_irq_restore(flags);
  62        }
  63}
  64EXPORT_SYMBOL(on_each_cpu_mask);
  65
  66/*
  67 * Preemption is disabled here to make sure the cond_func is called under the
  68 * same condtions in UP and SMP.
  69 */
  70void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info),
  71                      smp_call_func_t func, void *info, bool wait,
  72                      gfp_t gfp_flags)
  73{
  74        unsigned long flags;
  75
  76        preempt_disable();
  77        if (cond_func(0, info)) {
  78                local_irq_save(flags);
  79                func(info);
  80                local_irq_restore(flags);
  81        }
  82        preempt_enable();
  83}
  84EXPORT_SYMBOL(on_each_cpu_cond);
  85