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From: Sujith Manoharan <c_manoha@qca.qualcomm.com>
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Date: Tue, 17 Jul 2012 17:05:16 +0530
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To: Felix Fietkau <nbd@openwrt.org>
CC: Sujith Manoharan <c_manoha@qca.qualcomm.com>,
	"linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>,
	"linville@tuxdriver.com" <linville@tuxdriver.com>,
	"Rodriguez, Luis" <rodrigue@qca.qualcomm.com>
Subject: Re: [PATCH v2 08/12] ath9k: fix aggregate size limit based on queue TXOP limit
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Felix Fietkau wrote:
> The way I understand this, the TXOP limit is meant to limit the duration
> of a single transmission on the channel. An aggregate is transmitted in
> one go, there's no SIFS or extra PHY headers inbetween, just short
> delimiters. So an A-MPDU should be treated pretty much like an MPDU
> here, its transmission duration should not exceed the TXOP limit.

Yeah, makes sense.

But we need to handle multiple interfaces, otherwise this would break
modes like P2P. For example, bring up a P2P-GO and setup a HT20 network,
and then bring up a new station interface - this would unconditionally
update the aggr. limits of the existing network. This wasn't the case earlier
since the limits were being maintained globally and were common to all interfaces
and addition/removal of new interfaces would not change the aggr. limits.

Sujith