From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <shemminger@vyatta.com>
Subject: Re: [PATCH v3 03/10] net: Add netdev interfaces recording
 send/compl
Date: Wed, 23 Nov 2011 16:03:20 -0800
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To: David Miller <davem@davemloft.net>
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On Wed, 23 Nov 2011 18:58:12 -0500 (EST)
David Miller <davem@davemloft.net> wrote:

> From: Stephen Hemminger <shemminger@vyatta.com>
> Date: Wed, 23 Nov 2011 09:46:14 -0800
> 
> > Since all the drivers that you show do this for one packet at a time,
> > why bother with a packets arguement to netdev_sent_queue()?
> 
> They batch the completion, that's why f.e. e1000e's changes keep track of
> pkts_compl and bytes_compl, and then pass that in at the end of the TX
> completion processing so that we only invoke these interfaces once per
> run instead of once per packet.

I was referring to the transmit routine, there for netdev_sent_queue()
is always called with one packet.

Many drivers batch packets in completion, and call netdev_completed_queue()
with multiple packets (and bytes).