linux tasklet
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tasklet_vecÁ´±íµÄÍ·²¿£¬²¢»½ÐѺǫ́Ïß³Ìksoftirqd¡£µ±ºǫ́Ïß³ÌksoftirqdÔËÐе÷ÓÃ__do_softirqʱ£¬»áÖ´ÐÐÔÚÖжÏ
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void tasklet_init(struct tasklet_struct *t,
void (*func)(unsigned long), unsigned long data)
{
t->next = NULL;
t->state = 0;
atomic_set(&t->count, 0);
t->func = func;
t->data = data;
}
Çý¶¯³ÌÐòµ÷Óú¯Êýtasklet_scheduleÀ´ÔËÐÐtasklet¡£
static inline void tasklet_schedule(struct tasklet_struct *t)
{
if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
__tasklet_schedule(t);
}
º¯Êý__tasklet_scheduleµÃµ½µ±Ç°CPUµÄtasklet_vecÁ´±í£¬²¢Ö´ÐÐTASKLET_SOFTIRQÈíÖжϡ£
void fastcall __tasklet_schedule(struct tasklet_struct *t)
{
unsigned long flags;
local_irq_save(flags);
t->next = __get_cpu_var(tasklet_vec).list;
__get_cpu_var(tasklet_vec).list = t;
raise_softirq_irqoff(TASKLET_SOFTIRQ);
local_irq_restore(flags);
}
º¯Êýraise_softirq_irqoffÉèÖÃÈíÖжÏnrΪ¹ÒÆð״̬£¬²¢ÔÚûÓÐÖжÏʱ»½ÐÑÏß³Ìksoftirqd¡£º¯Êýraise_softirq_irqoff±ØÐëÔÚ¹ØÖжÏÇé¿öÏÂÔËÐС£
inline fastcall void raise_softirq_irqoff(unsigned int nr)
{
__raise_softirq_irqoff(nr);
/*
* If we're in an interrupt or softirq, we're done
* (this also catches softirq-disabled code). We will
* actually run the softirq once we return from
* the irq or softirq.
*
*
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