摘至：http://www.makelinux.net/books/lkd2/ch06lev1sec7

Interrupt Control

The Linux kernel implements a family of interfaces for manipulating the state of interrupts on a machine. These interfaces enable you to disable the interrupt system for the current processor or mask out an interrupt line for the entire machine. 

Disabling and Enabling Interrupts

To disable interrupts locally for the current processor (and only the current processor) and then later reenable them, do the following

local_irq_disable();
/* interrupts are disabled .. */
local_irq_enable();

These functions are usually implemented as a single assembly operation (of course, this depends on the architecture). Indeed, on x86, local_irq_disable() is a simple cli and local_irq_enable() is a simple sti instruction. For non-x86 hackers, cli and sti are the assembly calls to clear and set the allow interrupts flag, respectively. In other words, they disable and enable interrupt delivery on the issuing processor.

Disabling a Specific Interrupt Line

In the previous section, we looked at functions that disable all interrupt delivery for an entire processor. In some cases, it is useful to disable only a specific interrupt line for the entire system. This is called masking out an interrupt line. As an example, you might want to disable delivery of a device's interrupts before manipulating its state. Linux provides four interfaces for this task:

void disable_irq(unsigned int irq);
void disable_irq_nosync(unsigned int irq);
void enable_irq(unsigned int irq);
void synchronize_irq(unsigned int irq);