1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Uniprocessor-only support functions. The counterpart to kernel/smp.c
4 */
5
6 #include <linux/interrupt.h>
7 #include <linux/kernel.h>
8 #include <linux/export.h>
9 #include <linux/smp.h>
10 #include <linux/hypervisor.h>
11
smp_call_function_single(int cpu,void (* func)(void * info),void * info,int wait)12 int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
13 int wait)
14 {
15 unsigned long flags;
16
17 if (cpu != 0)
18 return -ENXIO;
19
20 local_irq_save(flags);
21 func(info);
22 local_irq_restore(flags);
23
24 return 0;
25 }
26 EXPORT_SYMBOL(smp_call_function_single);
27
smp_call_function_single_async(int cpu,call_single_data_t * csd)28 int smp_call_function_single_async(int cpu, call_single_data_t *csd)
29 {
30 unsigned long flags;
31
32 local_irq_save(flags);
33 csd->func(csd->info);
34 local_irq_restore(flags);
35 return 0;
36 }
37 EXPORT_SYMBOL(smp_call_function_single_async);
38
on_each_cpu(smp_call_func_t func,void * info,int wait)39 void on_each_cpu(smp_call_func_t func, void *info, int wait)
40 {
41 unsigned long flags;
42
43 local_irq_save(flags);
44 func(info);
45 local_irq_restore(flags);
46 }
47 EXPORT_SYMBOL(on_each_cpu);
48
49 /*
50 * Note we still need to test the mask even for UP
51 * because we actually can get an empty mask from
52 * code that on SMP might call us without the local
53 * CPU in the mask.
54 */
on_each_cpu_mask(const struct cpumask * mask,smp_call_func_t func,void * info,bool wait)55 void on_each_cpu_mask(const struct cpumask *mask,
56 smp_call_func_t func, void *info, bool wait)
57 {
58 unsigned long flags;
59
60 if (cpumask_test_cpu(0, mask)) {
61 local_irq_save(flags);
62 func(info);
63 local_irq_restore(flags);
64 }
65 }
66 EXPORT_SYMBOL(on_each_cpu_mask);
67
68 /*
69 * Preemption is disabled here to make sure the cond_func is called under the
70 * same condtions in UP and SMP.
71 */
on_each_cpu_cond_mask(smp_cond_func_t cond_func,smp_call_func_t func,void * info,bool wait,const struct cpumask * mask)72 void on_each_cpu_cond_mask(smp_cond_func_t cond_func, smp_call_func_t func,
73 void *info, bool wait, const struct cpumask *mask)
74 {
75 unsigned long flags;
76
77 preempt_disable();
78 if (cond_func(0, info)) {
79 local_irq_save(flags);
80 func(info);
81 local_irq_restore(flags);
82 }
83 preempt_enable();
84 }
85 EXPORT_SYMBOL(on_each_cpu_cond_mask);
86
on_each_cpu_cond(smp_cond_func_t cond_func,smp_call_func_t func,void * info,bool wait)87 void on_each_cpu_cond(smp_cond_func_t cond_func, smp_call_func_t func,
88 void *info, bool wait)
89 {
90 on_each_cpu_cond_mask(cond_func, func, info, wait, NULL);
91 }
92 EXPORT_SYMBOL(on_each_cpu_cond);
93
smp_call_on_cpu(unsigned int cpu,int (* func)(void *),void * par,bool phys)94 int smp_call_on_cpu(unsigned int cpu, int (*func)(void *), void *par, bool phys)
95 {
96 int ret;
97
98 if (cpu != 0)
99 return -ENXIO;
100
101 if (phys)
102 hypervisor_pin_vcpu(0);
103 ret = func(par);
104 if (phys)
105 hypervisor_pin_vcpu(-1);
106
107 return ret;
108 }
109 EXPORT_SYMBOL_GPL(smp_call_on_cpu);
110
