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 #include <linux/hypervisor.h> 10 11 int smp_call_function_single(int cpu, void (*func) (void *info), void *info, 12 int wait) 13 { 14 unsigned long flags; 15 16 WARN_ON(cpu != 0); 17 18 local_irq_save(flags); 19 func(info); 20 local_irq_restore(flags); 21 22 return 0; 23 } 24 EXPORT_SYMBOL(smp_call_function_single); 25 26 int smp_call_function_single_async(int cpu, call_single_data_t *csd) 27 { 28 unsigned long flags; 29 30 local_irq_save(flags); 31 csd->func(csd->info); 32 local_irq_restore(flags); 33 return 0; 34 } 35 EXPORT_SYMBOL(smp_call_function_single_async); 36 37 int on_each_cpu(smp_call_func_t func, void *info, int wait) 38 { 39 unsigned long flags; 40 41 local_irq_save(flags); 42 func(info); 43 local_irq_restore(flags); 44 return 0; 45 } 46 EXPORT_SYMBOL(on_each_cpu); 47 48 /* 49 * Note we still need to test the mask even for UP 50 * because we actually can get an empty mask from 51 * code that on SMP might call us without the local 52 * CPU in the mask. 53 */ 54 void on_each_cpu_mask(const struct cpumask *mask, 55 smp_call_func_t func, void *info, bool wait) 56 { 57 unsigned long flags; 58 59 if (cpumask_test_cpu(0, mask)) { 60 local_irq_save(flags); 61 func(info); 62 local_irq_restore(flags); 63 } 64 } 65 EXPORT_SYMBOL(on_each_cpu_mask); 66 67 /* 68 * Preemption is disabled here to make sure the cond_func is called under the 69 * same condtions in UP and SMP. 70 */ 71 void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info), 72 smp_call_func_t func, void *info, bool wait, 73 gfp_t gfp_flags) 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); 86 87 int smp_call_on_cpu(unsigned int cpu, int (*func)(void *), void *par, bool phys) 88 { 89 int ret; 90 91 if (cpu != 0) 92 return -ENXIO; 93 94 if (phys) 95 hypervisor_pin_vcpu(0); 96 ret = func(par); 97 if (phys) 98 hypervisor_pin_vcpu(-1); 99 100 return ret; 101 } 102 EXPORT_SYMBOL_GPL(smp_call_on_cpu); 103