diff options
-rw-r--r-- | kernel/sched_idletask.c | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/kernel/sched_idletask.c b/kernel/sched_idletask.c new file mode 100644 index 000000000000..41841e741c4a --- /dev/null +++ b/kernel/sched_idletask.c @@ -0,0 +1,71 @@ +/* + * idle-task scheduling class. + * + * (NOTE: these are not related to SCHED_IDLE tasks which are + * handled in sched_fair.c) + */ + +/* + * Idle tasks are unconditionally rescheduled: + */ +static void check_preempt_curr_idle(struct rq *rq, struct task_struct *p) +{ + resched_task(rq->idle); +} + +static struct task_struct *pick_next_task_idle(struct rq *rq, u64 now) +{ + schedstat_inc(rq, sched_goidle); + + return rq->idle; +} + +/* + * It is not legal to sleep in the idle task - print a warning + * message if some code attempts to do it: + */ +static void +dequeue_task_idle(struct rq *rq, struct task_struct *p, int sleep, u64 now) +{ + spin_unlock_irq(&rq->lock); + printk(KERN_ERR "bad: scheduling from the idle thread!\n"); + dump_stack(); + spin_lock_irq(&rq->lock); +} + +static void put_prev_task_idle(struct rq *rq, struct task_struct *prev, u64 now) +{ +} + +static int +load_balance_idle(struct rq *this_rq, int this_cpu, struct rq *busiest, + unsigned long max_nr_move, unsigned long max_load_move, + struct sched_domain *sd, enum cpu_idle_type idle, + int *all_pinned, unsigned long *total_load_moved) +{ + return 0; +} + +static void task_tick_idle(struct rq *rq, struct task_struct *curr) +{ +} + +/* + * Simple, special scheduling class for the per-CPU idle tasks: + */ +static struct sched_class idle_sched_class __read_mostly = { + /* no enqueue/yield_task for idle tasks */ + + /* dequeue is not valid, we print a debug message there: */ + .dequeue_task = dequeue_task_idle, + + .check_preempt_curr = check_preempt_curr_idle, + + .pick_next_task = pick_next_task_idle, + .put_prev_task = put_prev_task_idle, + + .load_balance = load_balance_idle, + + .task_tick = task_tick_idle, + /* no .task_new for idle tasks */ +}; |