From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH take 2] pkt_sched: Fix qdisc_watchdog() vs.
 dev_deactivate() race
Date: Fri, 12 Sep 2008 18:40:08 -0700 (PDT)
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From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Fri, 12 Sep 2008 18:27:58 -0700

> On Fri, Sep 12, 2008 at 06:22:59PM -0700, David Miller wrote:
> > And then there are all of these complicated pieces of state the
> > classful qdiscs modify when a SKB is removed from their visibility.
> > So, the unlink isn't just a simple list delete operation.  There
> > are queue lengths that need to be updated, watchdog timers to
> > manage, etc.
> 
> The decision really comes down to whether it's harder to requeue
> a seemingly arbitrary packet or whether it's harder to dequeue the
> packet that was last peeked.

My current opinion is that both operations are equally difficult.
With the slight advantage for ->requeue() because all the complicated
logic is already implemented :-)