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