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From: David Miller <davem@davemloft.net>
Subject: Re: Generic rx-recycling and emergency skb pool
Date: Fri, 02 Jul 2010 23:46:45 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Sat, 03 Jul 2010 08:23:25 +0200

> Maybe its time to provide new API, so that a driver can build an skb at
> the time RX interrupt is handled, not at the time the rx ring buffer is
> renewed. RX ring should only provide the data part to NIC, and skb
> should be built when NIC delivers the frame, so that we provide to IP
> stack a real hot skb.

Drivers do this already, and in fact I am very sure I'm mentioned this
to you at least other time in the past, and one such driver is NIU :-)

It's trivial to do with devices which work on power-of-2 chopped up
pages.  In fact I'm surprised that RX buffer management scheme is
not more prevalent in network devices.