From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gagan Arneja <gaagaan@gmail.com>
Subject: Re: [RFC] New driver API to speed up small packets xmits
Date: Thu, 10 May 2007 22:35:47 -0700
Message-ID: <464400B3.7050404@gmail.com>
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Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>, netdev@vger.kernel.org,
	Rick Jones <rick.jones2@hp.com>,
	Sridhar Samudrala <sri@us.ibm.com>
To: Krishna Kumar2 <krkumar2@in.ibm.com>
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Krishna Kumar2 wrote:
> I haven't seen reordering packets (I did once when I was having a bug in
> the requeue code, some TCP messages on receiver indicating packets out of
> order). When a send fails, the packet are requeued in reverse (go to end of
> the failed skb and traverse back to the failed skb and requeue each skb).
> Since new inserts go to the end, the queue is guaranteed to be in order.

queue_lock is dropped when you're in xmit. There's no guarantee packets 
won't be queued up while you're trying a transmit.

> 
> Thanks,
> 
> - KK
>