Subject: Re: [RFT] mac80211: fix broadcast/multicast data drop on scan
From: Johannes Berg <johannes@sipsolutions.net>
To: "Luis R. Rodriguez" <lrodriguez@atheros.com>
Cc: Jouni Malinen <j@w1.fi>, linux-wireless@vger.kernel.org,
	Kalle Valo <kvalo@adurom.com>,
	Amod Bodas <Amod.Bodas@atheros.com>
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Date: Fri, 27 Aug 2010 17:51:34 +0200
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On Fri, 2010-08-27 at 08:48 -0700, Luis R. Rodriguez wrote:

> > Well, there's no way we can reliably wake up exactly before a beacon by
> > implementing that in software, hard real-time hasn't been achieved in
> > Linux yet :-)
> 
> Keyword here is *exactly*. I don't want to wake up *exactly* at DTIM,
> only ensure we don't sleep during it and the send buffered frames and
> multicast traffic data. Why can we not implement this on mac80211?

Well, how long before the beacon do you want to wake up to catch it?
1ms? 10ms? 100ms? 1000ms? What if the system is busy?

johannes