1/* 2 * SMP stuff which is common to all sub-architectures. 3 */ 4#include <linux/module.h> 5#include <asm/smp.h> 6 7DEFINE_PER_CPU(unsigned long, this_cpu_off); 8EXPORT_PER_CPU_SYMBOL(this_cpu_off); 9 10/* Initialize the CPU's GDT. This is either the boot CPU doing itself 11 (still using the master per-cpu area), or a CPU doing it for a 12 secondary which will soon come up. */ 13__cpuinit void init_gdt(int cpu) 14{ 15 struct desc_struct *gdt = get_cpu_gdt_table(cpu); 16 17 pack_descriptor((u32 *)&gdt[GDT_ENTRY_PERCPU].a, 18 (u32 *)&gdt[GDT_ENTRY_PERCPU].b, 19 __per_cpu_offset[cpu], 0xFFFFF, 20 0x80 | DESCTYPE_S | 0x2, 0x8); 21 22 per_cpu(this_cpu_off, cpu) = __per_cpu_offset[cpu]; 23 per_cpu(cpu_number, cpu) = cpu; 24} 25 26 27/** 28 * smp_call_function(): Run a function on all other CPUs. 29 * @func: The function to run. This must be fast and non-blocking. 30 * @info: An arbitrary pointer to pass to the function. 31 * @nonatomic: Unused. 32 * @wait: If true, wait (atomically) until function has completed on other CPUs. 33 * 34 * Returns 0 on success, else a negative status code. 35 * 36 * If @wait is true, then returns once @func has returned; otherwise 37 * it returns just before the target cpu calls @func. 38 * 39 * You must not call this function with disabled interrupts or from a 40 * hardware interrupt handler or from a bottom half handler. 41 */ 42int smp_call_function(void (*func) (void *info), void *info, int nonatomic, 43 int wait) 44{ 45 return smp_call_function_mask(cpu_online_map, func, info, wait); 46} 47EXPORT_SYMBOL(smp_call_function); 48 49/** 50 * smp_call_function_single - Run a function on another CPU 51 * @cpu: The target CPU. Cannot be the calling CPU. 52 * @func: The function to run. This must be fast and non-blocking. 53 * @info: An arbitrary pointer to pass to the function. 54 * @nonatomic: Unused. 55 * @wait: If true, wait until function has completed on other CPUs. 56 * 57 * Returns 0 on success, else a negative status code. 58 * 59 * If @wait is true, then returns once @func has returned; otherwise 60 * it returns just before the target cpu calls @func. 61 */ 62int smp_call_function_single(int cpu, void (*func) (void *info), void *info, 63 int nonatomic, int wait) 64{ 65 /* prevent preemption and reschedule on another processor */ 66 int ret; 67 int me = get_cpu(); 68 if (cpu == me) { 69 WARN_ON(1); 70 put_cpu(); 71 return -EBUSY; 72 } 73 74 ret = smp_call_function_mask(cpumask_of_cpu(cpu), func, info, wait); 75 76 put_cpu(); 77 return ret; 78} 79EXPORT_SYMBOL(smp_call_function_single); 80