diff options
Diffstat (limited to 'arch/x86/kernel/smpcommon_32.c')
-rw-r--r-- | arch/x86/kernel/smpcommon_32.c | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/arch/x86/kernel/smpcommon_32.c b/arch/x86/kernel/smpcommon_32.c new file mode 100644 index 000000000000..bbfe85a0f699 --- /dev/null +++ b/arch/x86/kernel/smpcommon_32.c | |||
@@ -0,0 +1,81 @@ | |||
1 | /* | ||
2 | * SMP stuff which is common to all sub-architectures. | ||
3 | */ | ||
4 | #include <linux/module.h> | ||
5 | #include <asm/smp.h> | ||
6 | |||
7 | DEFINE_PER_CPU(unsigned long, this_cpu_off); | ||
8 | EXPORT_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 | */ | ||
42 | int 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 | } | ||
47 | EXPORT_SYMBOL(smp_call_function); | ||
48 | |||
49 | /** | ||
50 | * smp_call_function_single - Run a function on a specific 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 | */ | ||
62 | int 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 | local_irq_disable(); | ||
70 | func(info); | ||
71 | local_irq_enable(); | ||
72 | put_cpu(); | ||
73 | return 0; | ||
74 | } | ||
75 | |||
76 | ret = smp_call_function_mask(cpumask_of_cpu(cpu), func, info, wait); | ||
77 | |||
78 | put_cpu(); | ||
79 | return ret; | ||
80 | } | ||
81 | EXPORT_SYMBOL(smp_call_function_single); | ||