Re: [PATCH] avoid race condition in pick_next_task_fair in kernel/sched_fair.c

From: shenghui
Date: Tue Jun 29 2010 - 07:24:27 EST


2010/6/29 Peter Zijlstra <peterz@xxxxxxxxxxxxx>:
> On Tue, 2010-06-29 at 15:10 +0800, shenghui wrote:
>> I think some lock on the metadata can fix this issue, but we may
>> change plenty of code to add support for lock. I think the easist
>> way is just substacting nr_running before dequing tasks.
>
> But all that is fully serialized by the rq->lock.. so I'm really not
> seeing how this can happen.
>
>
>

I wonder is there any chance set_next_entity() can get NULL for
parameter se if so?
And will you please give me some instructions on where rq->lock
is required?

--


Thanks and Best Regards,
shenghui
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/