Messages in this thread | | | Subject | Re: [PATCH] avoid race condition in pick_next_task_fair in kernel/sched_fair.c | From | Peter Zijlstra <> | Date | Tue, 29 Jun 2010 13:35:16 +0200 |
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On Tue, 2010-06-29 at 19:24 +0800, shenghui wrote:
> I wonder is there any chance set_next_entity() can get NULL for > parameter se if so?
Well, if your machine crashes that way, maybe, but I haven't seen that happen in a long while.
> And will you please give me some instructions on where rq->lock > is required?
Pretty much everywhere, if you look at sched.c the only sched_class method not called with rq->lock held is ::task_fork().
The interesting bits are that schedule()->pre_schedule()/idle_balance() can drop rq->lock as well as ->select_task_rq().
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