Message-ID: <ea2b998e692235f0d7e4314d9b010eeac20e403f.camel@sipsolutions.net>
Subject: Re: [PATCH] nl80211/cfg80211: Add support to specify band specific
 min rssi thresholds with sched scan
From:   Johannes Berg <johannes@sipsolutions.net>
To:     vamsin@codeaurora.org
Cc:     linux-wireless@vger.kernel.org, jouni@codeaurora.org
Date:   Fri, 25 Jan 2019 21:44:34 +0100
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On Tue, 2019-01-22 at 17:00 +0530, vamsin@codeaurora.org wrote:

> > > > It seems that this should be with the existing
> > > > NL80211_SCHED_SCAN_MATCH_ATTR_RSSI, not in this level namespace.
> > > 
> > > The band specific rssi thresholds that are being configured are global
> > > across all matchsets whereas NL80211_SCHED_SCAN_MATCH_ATTR_* 
> > > attributes
> > > are mostly specific to each matchset. Hence I choose to define
> > > attributes in higher level namespace. In future, whenever we want to
> > > adding support for rssi thresholds per band and per matchset, we can
> > > define attributes within NL80211_SCHED_SCAN_MATCH_ATTR_* namespace
> > > level.
> > 
> > But why do we want global ones now?
> > 
> 
> The global thresholds were there earlier as well. Earlier, we were using 
> a matchset with only rssi attribute without any ssid/bssid attribute 
> within the matchset. I thought having global attributes for specifying 
> global thresholds is better way going forward and avoids unnecessary 
> confusion. Mostly, same thresholds will be used for all ssids/bssids in 
> general rather than thresholds specific to ssid/bssid. However, I 
> couldn't see any disadvantage of using global attributes for this case, 
> please let me know if you see any disadvantage/concern with this.

I just think it's more complex code, overall.

To me we now have sort of a fork in the road

global RSSI ---> per-matchset RSSI
           \
            \--> global band-specific RSSI

so it seems somebody will want to introduce per-matchset band-specific
RSSI eventually, and that just makes it even more complex?

What's the downside of going to per-matchset band-specific RSSI?

johannes