397 void do_IRQ(struct pt_regs *rsp, ul number)  in do_IRQ()  argument
400     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()
403         irq_desc_t *irq = &interrupt_desc[number - 32];  in do_IRQ()
407             irq->handler(number, irq->parameter, rsp);  in do_IRQ()
412             irq->controller->ack(number);  in do_IRQ()
416     else if (number >= 200)  in do_IRQ()
418         apic_local_apic_edge_ack(number);  in do_IRQ()
421             irq_desc_t *irq = &SMP_IPI_desc[number - 200];  in do_IRQ()
423                 irq->handler(number, irq->parameter, rsp);  in do_IRQ()
426     else if (number >= 150 && number < 200)  in do_IRQ()
428         irq_desc_t *irq = &local_apic_interrupt_desc[number - 150];  in do_IRQ()
432             irq->handler(number, irq->parameter, rsp);  in do_IRQ()
437             irq->controller->ack(number);  in do_IRQ()
444         kwarn("do IRQ receive: %d", number);  in do_IRQ()