From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rob Herring <robherring2@gmail.com>
Subject: Re: [PATCH v2] net: calxedaxgmac: rework transmit ring handling
Date: Fri, 12 Oct 2012 15:21:59 -0500
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Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
	jonathan@jonmasters.org,
	Mark Langsdorf <mark.langsdorf@calxeda.com>,
	Rob Herring <rob.herring@calxeda.com>,
	Ben Hutchings <bhutchings@solarflare.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
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Eric Dumazet <eric.dumazet@gmail.com> wrote:

>On Fri, 2012-10-12 at 13:04 -0500, Rob Herring wrote:
>> From: Rob Herring <rob.herring@calxeda.com>
>> 
>> Only generate tx interrupts on every ring size / 4 descriptors. Move
>the
>> netif_stop_queue call to the end of the xmit function rather than
>> checking at the beginning.
>> 
>> Signed-off-by: Rob Herring <rob.herring@calxeda.com>
>> ---
>> v2:
>> - Add missed enabling of the descriptor tx interrupt
>
>Seems to be net-next material to me.
>

Perhaps, but the series as a whole is what I've been testing. This one has the least performance impact.

>Furthermore, your changelog is a bit terse for such a patch, that could
>easily break upper layers.
>
>You need to tell us how long TX completion for a packet might be
>deferred.

The prior behavior was only interrupting when done with all buffers.  It now will interrupt before completely emptying the ring.

Rob