Re: want opinions on possible glitch in 2.4 network error reporting

Chris Friesen (cfriesen@nortelnetworks.com)
Thu, 07 Feb 2002 10:59:56 -0500


Andi Kleen wrote:
>
> Chris Friesen <cfriesen@nortelnetworks.com> writes:
>
> > I've been looking around in the 2.4 networking stack, and I noticed that when
> > the tulip (and no doubt many other) driver cannot put any more outgoing packets
> > on the queue, it calls netif_stop_queue(). Then, in dev_queue_xmit() we check
> > this flag by calling netif_queue_stopped(). My concern is that if this flag is
> > true, we return -ENETDOWN. Is this really the proper return code for this? If
> > anything, the network is too active. It seems to me that it would make more
> > sense to have some kind of congestion return code rather than claiming that the
> > network is down.
>
> The ENETDOWN path you're seeing only applies to queueless devices (like
> loopback or a tunnel device). These should only set the queued stopped
> flag when something is terrible wrong.
>
> All real network devices have a queue and go through the qdisc.

Okay, I must be missing something, so can you enlighten me? I can't figure out
where the qdisc is attached to the ethernet device.

Chris

-- 
Chris Friesen                    | MailStop: 043/33/F10  
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