From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jon Mason <jdmason@us.ibm.com>
Subject: Re: RFC: NAPI packet weighting patch
Date: Fri, 3 Jun 2005 16:12:10 -0500
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To: "David S. Miller" <davem@davemloft.net>
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On Friday 03 June 2005 03:31 pm, David S. Miller wrote:
> From: jamal <hadi@cyberus.ca>
> Date: Fri, 03 Jun 2005 15:59:31 -0400
>
> > But one that you could validate by putting proper hooks. As an example,
> > try to restore a descriptor every time you pick one - for an example of
> > this look at the sb1250 driver.
>
> Yes, this in my mind is exactly the problem.  TG3 does this
> properly, as do several other drivers.
>
> You should never defer RX buffer replenishment, you should
> always do it as you grab packets off of the ring.  You will
> starve the chip otherwise.

e1000 isn't the only driver to do things this way.  r8169, via-velocity, dl2k, 
and skge (and I'm sure many more).  Might be nice to perform a driver audit 
to see what drivers do this.