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
smp_call_function_single(int cpu,void (* func)(void * info),void * info,int wait)10 int 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 }
23 EXPORT_SYMBOL(smp_call_function_single);
24
smp_call_function_single_async(int cpu,struct call_single_data * csd)25 int 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 }
34 EXPORT_SYMBOL(smp_call_function_single_async);
35
on_each_cpu(smp_call_func_t func,void * info,int wait)36 int 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 }
45 EXPORT_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 */
on_each_cpu_mask(const struct cpumask * mask,smp_call_func_t func,void * info,bool wait)53 void 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 }
64 EXPORT_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 */
on_each_cpu_cond(bool (* cond_func)(int cpu,void * info),smp_call_func_t func,void * info,bool wait,gfp_t gfp_flags)70 void 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 }
84 EXPORT_SYMBOL(on_each_cpu_cond);
85