Now that the idle_balance is called from the post_schedule of the idle task sched class, it is safe to enable interrupts. This allows for better interaction of tasks waking up and other interrupts that are triggered while the idle balance is in process.
Preemption is still disabled, but perhaps that can change as well. That may need some more investigation. Signed-off-by: Steven Rostedt <[email protected]> Index: linux-trace.git/kernel/sched/fair.c =================================================================== --- linux-trace.git.orig/kernel/sched/fair.c +++ linux-trace.git/kernel/sched/fair.c @@ -5231,9 +5231,10 @@ void idle_balance(int this_cpu, struct r update_rq_runnable_avg(this_rq, 1); /* - * Drop the rq->lock, but keep IRQ/preempt disabled. + * Drop the rq->lock, but keep preempt disabled. */ - raw_spin_unlock(&this_rq->lock); + preempt_disable(); + raw_spin_unlock_irq(&this_rq->lock); update_blocked_averages(this_cpu); rcu_read_lock(); @@ -5260,7 +5261,8 @@ void idle_balance(int this_cpu, struct r } rcu_read_unlock(); - raw_spin_lock(&this_rq->lock); + raw_spin_lock_irq(&this_rq->lock); + preempt_enable(); if (pulled_task || time_after(jiffies, this_rq->next_balance)) { /* -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
