Subject: Re: [RFC/T][PATCH 1/3] rc80211-pid: introduce rate behaviour
	learning algorithm
From: Johannes Berg <johannes@sipsolutions.net>
To: Mattias Nissler <mattias.nissler@gmx.de>
Cc: Stefano Brivio <stefano.brivio@polimi.it>,
	linux-wireless <linux-wireless@vger.kernel.org>,
	"John W. Linville" <linville@tuxdriver.com>
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Date: Wed, 12 Dec 2007 18:13:14 +0100
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> Just to sum up the issue for Johannes: Stefano's patch adds per-rate
> information to the PID algorithm state. This is fine, however we need to
> make sure the rate control algorithm gets reinitialized when the number
> of rates changes (i.e. due to a mode change, what about about regulatory
> domain changes?), as otherwise we might be indexing array entries we
> don't have allocated. Now this spawned the more general discussion about
> when the stack should allow changing modes etc.

Thanks.

> So let's go back to the original issue: Johannes, can we assume rate
> control always gets reinitialized when the number of rates or even the
> hardware mode is changed?

I have no idea. Doesn't it get initialised when the interface is brought
up, and as such it would because those changes can only be done when
it's down? If we want to be strict and allow changes while it's not
associated but up then I think the answer is a clear no.

johannes

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