Messages in this thread | | | From | (Alan Cox) | Subject | Re: peeking the netdevice queue | Date | Wed, 6 Jan 1999 15:00:38 +0000 (GMT) |
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> In my COSA driver (www.fi.muni.cz/~kas/cosa) it would help > to improve the effectivity of the driver, because in the end-of-transmit > interrupt the driver should tell the device if it has another packet > ready for transmit. The present driver tells the card there are no more > packets waiting for transmit and lets the dev->hard_start_xmit() to start > the new transmit later.
As soon as you've done mark_bh(NET_BH) and returned from your IRQ you will get called from the bottom half handler. The tiny delay there isn't normally a problem because cards go to "busy" state when their own buffers are full which is usually at least 2 frames, you therefore have a whole frame time to load the next packet.
Its not always true. The Z85230 driver it isnt true for, and that simply keeps hold of a single "next packet" buffer. Thats sufficient to keep it well fed and happy.
> I have looked at other drivers - for example the 3c59x.c > implements its own internal queue of packets waiting for transmit
That one is well overkill
Alan
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