Linux Device Drivers Development

Tasklet scheduling

There are two scheduling functions for a tasklet, depending on whether your tasklet has normal or higher priority:

void tasklet_schedule(struct tasklet_struct *t); 
void tasklet_hi_schedule(struct tasklet_struct *t);

The kernel maintains normal priority and high priority tasklets in two different lists. tasklet_schedule adds the tasklet into the normal priority list, scheduling the associated softirq with a TASKLET_SOFTIRQ flag. With tasklet_hi_schedule, the tasklet is added into the high priority list, scheduling the associated softirq with a HI_SOFTIRQ flag. High priority tasklets are meant to be used for soft interrupt handlers with low latency requirements. There are some properties associated with tasklets you should ...