From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <shemminger@vyatta.com>
Subject: Re: [PATCH] sched: QFQ - quick fair queue scheduler (v3)
Date: Thu, 3 Mar 2011 16:03:43 -0800
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Cc: David Miller <davem@davemloft.net>,
	Fabio Checconi <fabio@gandalf.sssup.it>,
	Luigi Rizzo <rizzo@iet.unipi.it>, netdev@vger.kernel.org
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Thu, 03 Mar 2011 23:28:53 +0100
Eric Dumazet <eric.dumazet@gmail.com> wrote:

> Here there is the problem of *pp = cl->next (possibly NULL)
> 
> 		maybe use
> 
> 	for (pp = &grp->slots[j]; (cl = *pp) != NULL;) {
> 		if (cl->qdisc->q.len)
> 			qfq_deactivate_class(...);
> 		else
> 			pp = &cl->next;
> 	}
> 

I think changing slots from open coded linked list
to double linked list (list_for_each) would be clearer
and avoid these kind of bugs. That is what DRR does.

--