On Sun, Jul 05, 2009 at 11:26:58AM +0800, Herbert Xu wrote:

Here's a another crazy idea:

Let's use dummy TX descriptors to generate an interrupt, either
with or without transmitting an actual packet on the wire depending
on the NIC.

Here's an even crazier idea that doesn't use dummy descriptors.

xmit(skb)

	if (TX queue contains no interrupting descriptor &&
	    qdisc is empty)
		mark TX descriptor as interrupting

	if (TX queue now contains an interrupting descriptor &&
	    qdisc len < 2)
		stop queue

	if (TX ring full)
		stop queue

clean()

 	do work
	wake queue as per usual

Cheers,
-- 
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Email: Herbert Xu ~{PmV>HI~} [off-list ref]
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