Re: [PATCH v2 2/2] mac80211: minstrel_ht: set A-MSDU tx limits based on selected max_prob_rate

[Felix Fietkau <nbd@openwrt.org>]

On 2016-03-03 15:55, Johannes Berg wrote:
> On Wed, 2016-02-24 at 10:29 +0100, Felix Fietkau wrote:
> 
>> +	/*
>> +	 * If the rate is slower than single-stream MCS4, limit A-MSDU to usual
>> +	 * data packet size
>> +	 */
>> +	if (g->duration[rate] > MCS_DURATION(1, 0, 104))
>> +		return 1500;
>> +
>> +	/*
>> +	 * If the rate is slower than single-stream MCS7, limit A-MSDU to twice
>> +	 * the usual data packet size
>> +	 */
>> +	if (g->duration[rate] > MCS_DURATION(1, 0, 260))
>> +		return 3000;
> 
> This isn't *quite* right, since you have to take an 802.11 header (vs.
> an ethernet header) into account, I think?
It's only a rough approximation anyway to prevent very large A-MSDUs
from being created with low rates.

- Felix