Android开发

先看__schedule实现/* * __schedule() is the main scheduler function. * * The main means of driving the scheduler and thus entering this function are: * * 1. Explicit blocking: mutex, semaphore,...

kernel通过preempt_count变量来判断是否处于中断(soft/hard/nmi)上下文,是否可以抢占,先看示例#define in_irq() (hardirq_count())#define hardirq_count() (preempt_count() & HARDIRQ_MASK)static __always_inline int preempt_cou...