Linux x86_64内核中断初始化

asmlinkage void __init start_kernel(void)
{
     
    lock_kernel();
    ...
     //初始化调度模块
    sched_init();

    ...
    sort_main_extable();
    // 初始化异常处理。
    trap_init();
    ...
    // 初始化外部中断
    init_IRQ();
    ...
    // 初始化定时器模块，同时，会注册定时器的软中断处理函数。
    init_timers();
    
    // 初始化软中断）
    softirq_init();
    time_init();
    ...
    // 初始化
    acpi_early_init();
}

//门初始化。初始化中断向量表。系统有固定的256个硬件中断向量。
void __init trap_init(void)
{
    
    set_intr_gate(0,&divide_error);
    set_intr_gate_ist(1,&debug,DEBUG_STACK);
    set_intr_gate_ist(2,&nmi,NMI_STACK);
    set_intr_gate(3,&int3);
    set_system_gate(4,&overflow);   /* int4-5 can be called from all */
    set_system_gate(5,&bounds);
    set_intr_gate(6,&invalid_op);
    set_intr_gate(7,&device_not_available);
    set_intr_gate_ist(8,&double_fault, DOUBLEFAULT_STACK);
    set_intr_gate(9,&coprocessor_segment_overrun);
    set_intr_gate(10,&invalid_TSS);
    set_intr_gate(11,&segment_not_present);
    set_intr_gate_ist(12,&stack_segment,STACKFAULT_STACK);
    set_intr_gate(13,&general_protection);
    set_intr_gate(14,&page_fault);
    set_intr_gate(15,&spurious_interrupt_bug);
    set_intr_gate(16,&coprocessor_error);
    set_intr_gate(17,&alignment_check);
#ifdef CONFIG_X86_MCE
    set_intr_gate_ist(18,&machine_check, MCE_STACK); 
#endif
    set_intr_gate(19,&simd_coprocessor_error);

#ifdef CONFIG_IA32_EMULATION
    set_system_gate(IA32_SYSCALL_VECTOR, ia32_syscall);
#endif
       
    set_intr_gate(KDB_VECTOR, call_debug);
       
    /*
     * Should be a barrier for any external CPU state.
     */
    cpu_init();
}

void __init init_IRQ(void)
{
    int i;
    /**
    * 该函数主要是初始化硬件
    * 1. 初始化本地APIC控制芯片
    * 2. 初始化8259A芯片
    /
    init_ISA_irqs();
    /*
     * 清空32以后的中断向量表。（除了系统调用和内核调试用的中断号）
     */
    for (i = 0; i < (NR_VECTORS - FIRST_EXTERNAL_VECTOR); i++) {
        int vector = FIRST_EXTERNAL_VECTOR + i;
        if (i >= NR_IRQS)
            break;
        if (vector != IA32_SYSCALL_VECTOR && vector != KDB_VECTOR) { 
            set_intr_gate(vector, interrupt[i]);
    }
    }
// 多处理器通信中断
#ifdef CONFIG_SMP

    set_intr_gate(FIRST_DEVICE_VECTOR, interrupt[0]);
    set_intr_gate(RESCHEDULE_VECTOR, reschedule_interrupt);
    set_intr_gate(INVALIDATE_TLB_VECTOR, invalidate_interrupt);
    set_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
#endif  
// 本地APIC中断
#ifdef CONFIG_X86_LOCAL_APIC
    /* self generated IPI for local APIC timer */
    set_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);
    set_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
    set_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
#endif
    setup_timer();

    if (!acpi_ioapic)
        setup_irq(2, &irq2);
}