405 void do_IRQ(struct pt_regs *rsp, ul number)  in do_IRQ()  argument
408     if (number < 0x80 && number >= 32) // 以0x80为界限，低于0x80的是外部中断控制器，高于0x80的是Local APIC  in do_IRQ()
411         irq_desc_t *irq = &interrupt_desc[number - 32];  in do_IRQ()
415             irq->handler(number, irq->parameter, rsp);  in do_IRQ()
420             irq->controller->ack(number);  in do_IRQ()
424     else if (number >= 200)  in do_IRQ()
426         apic_local_apic_edge_ack(number);  in do_IRQ()
429             irq_desc_t *irq = &SMP_IPI_desc[number - 200];  in do_IRQ()
431                 irq->handler(number, irq->parameter, rsp);  in do_IRQ()
434     else if (number >= 150 && number < 200)  in do_IRQ()
436         irq_desc_t *irq = &local_apic_interrupt_desc[number - 150];  in do_IRQ()
440             irq->handler(number, irq->parameter, rsp);  in do_IRQ()
445             irq->controller->ack(number);  in do_IRQ()
452         kwarn("do IRQ receive: %d", number);  in do_IRQ()
469     if (current_pcb->flags & PF_NEED_SCHED && number == APIC_TIMER_IRQ_NUM)  in do_IRQ()