next_task宏定义为:
#define next_task(p) list_entry(rcu_dereference((p)->tasks.next), struct task_struct,
tasks)
获取下一个PCB指针
---------------------------------------------------------------------------------------------------------------------------------------
current
#define current get_current()
#define get_current() (current_thread_info()->task)
static inline struct thread_info *current_thread_info(void)
{
register unsigned long sp asm ("sp");
return (struct thread_info *)(sp & ~(THREAD_SIZE - 1)); //用于将sp对其到内核栈栈底,即存放thread_info结构的地方,然后转换成
// thread_info *返回
}
---------------------------------------------------------------------------------------------------------------------------------------
for_each_process是在linux/sched.h中的宏定义:
#define for_each_process(p) for (p = &init_task ; (p = next_task(p)) != &init_task ; )