Subject: Re: [PATCH/RFC] synchronize_rcu(): high latency on idle system

From: Andi Kleen <[email-masked]>
Date: Sun, 13 Jan 2008 16:34:17 +0100

> I think it should be in netdev_unregister_kobject().  But that would
> only get rid of one of the two calls to synchronize_rcu() in the unregister_netdev.

Would be already an improvement.

> The other synchronize_rcu() is for qdisc's and not sure if that one can
> be removed?

The standard way to remove such calls is to set a "deleted" flag in the object,
then check and ignore such objects in the reader and finally remove the object with
call_rcu

I have not checked if that is really feasible for qdiscs.

-Andi