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Date: Sun, 12 Jun 2011 20:48:59 +0200
From: Michael =?UTF-8?B?QsO8c2No?= <m@bues.ch>
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Subject: Re: [RFC][PATCH] b43: do not try sending packets when ring can be
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On Sun, 12 Jun 2011 20:15:53 +0200
Rafał Miłecki <zajec5@gmail.com> wrote:
> Well, as I said, we may be unable to transmit the first element of the
> queue, but 2nd/3rd/... may be for different ring (qos) (we can
> transmit).
> 
> Looping through the whole queue every time, just to find packets we
> may transmit, sounds surely as a bad idea.

I don't think so. It's not that this is an actual queue anyway. It just acts
as a buffer to queue up one or two packets in the small race window of
actually filling up the DMA rings and stopping the mac80211 queue.
(It also acts as a context dispatcher in the first place, though).

So the "looping through the queue" just means checking if one or two packets
can be transmitted now.