projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| e32640a2 GC |
1 | /* |
| 2 | * SMP stuff which is common to all sub-architectures. | |
| 3 | */ | |
| 4 | #include <linux/module.h> | |
| 5 | #include <asm/smp.h> | |
| 6 | ||
| 7 | #ifdef CONFIG_X86_32 | |
| 8 | DEFINE_PER_CPU(unsigned long, this_cpu_off); | |
| 9 | EXPORT_PER_CPU_SYMBOL(this_cpu_off); | |
| 10 | ||
| 11 | /* Initialize the CPU's GDT. This is either the boot CPU doing itself | |
| 12 | (still using the master per-cpu area), or a CPU doing it for a | |
| 13 | secondary which will soon come up. */ | |
| 14 | __cpuinit void init_gdt(int cpu) | |
| 15 | { | |
| 16 | struct desc_struct *gdt = get_cpu_gdt_table(cpu); | |
| 17 | ||
| 18 | pack_descriptor(&gdt[GDT_ENTRY_PERCPU], | |
| 19 | __per_cpu_offset[cpu], 0xFFFFF, | |
| 20 | 0x2 | DESCTYPE_S, 0x8); | |
| 21 | ||
| 22 | gdt[GDT_ENTRY_PERCPU].s = 1; | |
| 23 | ||
| 24 | per_cpu(this_cpu_off, cpu) = __per_cpu_offset[cpu]; | |
| 25 | per_cpu(cpu_number, cpu) = cpu; | |
| 26 | } | |
| 27 | #endif | |
| 28 | ||
| 29 | /** | |
| 30 | * smp_call_function(): Run a function on all other CPUs. | |
| 31 | * @func: The function to run. This must be fast and non-blocking. | |
| 32 | * @info: An arbitrary pointer to pass to the function. | |
| 33 | * @nonatomic: Unused. | |
| 34 | * @wait: If true, wait (atomically) until function has completed on other CPUs. | |
| 35 | * | |
| 36 | * Returns 0 on success, else a negative status code. | |
| 37 | * | |
| 38 | * If @wait is true, then returns once @func has returned; otherwise | |
| 39 | * it returns just before the target cpu calls @func. | |
| 40 | * | |
| 41 | * You must not call this function with disabled interrupts or from a | |
| 42 | * hardware interrupt handler or from a bottom half handler. | |
| 43 | */ | |
| 44 | int smp_call_function(void (*func) (void *info), void *info, int nonatomic, | |
| 45 | int wait) | |
| 46 | { | |
| 47 | return smp_call_function_mask(cpu_online_map, func, info, wait); | |
| 48 | } | |
| 49 | EXPORT_SYMBOL(smp_call_function); | |
| 50 | ||
| 51 | /** | |
| 52 | * smp_call_function_single - Run a function on a specific CPU | |
| 53 | * @cpu: The target CPU. Cannot be the calling CPU. | |
| 54 | * @func: The function to run. This must be fast and non-blocking. | |
| 55 | * @info: An arbitrary pointer to pass to the function. | |
| 56 | * @nonatomic: Unused. | |
| 57 | * @wait: If true, wait until function has completed on other CPUs. | |
| 58 | * | |
| 59 | * Returns 0 on success, else a negative status code. | |
| 60 | * | |
| 61 | * If @wait is true, then returns once @func has returned; otherwise | |
| 62 | * it returns just before the target cpu calls @func. | |
| 63 | */ | |
| 64 | int smp_call_function_single(int cpu, void (*func) (void *info), void *info, | |
| 65 | int nonatomic, int wait) | |
| 66 | { | |
| 67 | /* prevent preemption and reschedule on another processor */ | |
| 68 | int ret; | |
| 69 | int me = get_cpu(); | |
| 70 | if (cpu == me) { | |
| 71 | local_irq_disable(); | |
| 72 | func(info); | |
| 73 | local_irq_enable(); | |
| 74 | put_cpu(); | |
| 75 | return 0; | |
| 76 | } | |
| 77 | ||
| 78 | ret = smp_call_function_mask(cpumask_of_cpu(cpu), func, info, wait); | |
| 79 | ||
| 80 | put_cpu(); | |
| 81 | return ret; | |
| 82 | } | |
| 83 | EXPORT_SYMBOL(smp_call_function_single); |