Re: [PATCH] mac80211: always pick a basic rate to tx RTS/CTS for pre-HT rates

[Johannes Berg <johannes@sipsolutions.net>]

On Fri, 2013-04-05 at 12:06 +0200, Karl Beldan wrote:
> From: Karl Beldan <karl.beldan@rivierawaves.com>
> 
> When the 1st rate control entry is a pre-HT rate we want to set
> rts_cts_rate_idx "as the fastest basic rate that is not faster than the
> data rate"(code comments).
> But in case some bss allowed rate indexes are lower than the lowest bss
> basic rate, if the rate control selects a rate among the formers for its
> 1st rate control entry, rts_cts_rate_idx remains 0 and is not a basic
> rate index.
> This commit sets rts_cts_rate_idx to the lowest bss basic rate index in
> this situation.

Ok after reviewing this again I applied it.


>  	if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
> -		s8 baserate = 0;
> +		u32 basic_rates = tx->sdata->vif.bss_conf.basic_rates;
> +		s8 baserate = basic_rates ? ffs(basic_rates - 1) : 0;

Note that this also assumes that rate 0 is a mandatory rate, which
presumably will always be true.

johannes