Message-ID: <1361911935.8440.18.camel@jlt4.sipsolutions.net> (sfid-20130226_215237_339392_8E4156A0)
Subject: Re: [PATCHv2 2/3] mac80211: mesh power save doze scheduling
From: Johannes Berg <johannes@sipsolutions.net>
To: Marco Porsch <marco@cozybit.com>
Cc: mcgrof@qca.qualcomm.com, jouni@qca.qualcomm.com,
	vthiagar@qca.qualcomm.com, senthilb@qca.qualcomm.com,
	sleffler@google.com, linux-wireless@vger.kernel.org,
	devel@lists.open80211s.org, ath9k-devel@lists.ath9k.org
Date: Tue, 26 Feb 2013 21:52:15 +0100
In-Reply-To: <512B37BA.6060605@cozybit.com> (sfid-20130225_110654_178953_AA37B00E)
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	  (sfid-20130218_170842_350606_DE89DB9F) <1361372480.8629.33.camel@jlt4.sipsolutions.net>
	 <512B37BA.6060605@cozybit.com> (sfid-20130225_110654_178953_AA37B00E)
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On Mon, 2013-02-25 at 11:06 +0100, Marco Porsch wrote:

> > This is strange, why bother with the else if there's a continue?
> 
> I don't quite get this comment. The current logic is like this:
> 
> if (unrelated cases) {
> 	continue;
> } else if (related and blocking) {
> 	allow = false;
> 	break;
> } else if (related, non-blocking and new minimum) {
> 	min = sta->nexttbtt;
> }

Yeah I guess I don't see why it's not just

        if (unrelated cases)
        	continue;
        
        if (related & blocking) {
        	allow = false;
        	break;
        }
        
        if (...)
        	min = ...
        
but it really doesn't matter much.

> >> +               } else if (test_sta_flag(sta, WLAN_STA_MPS_WAIT_FOR_CAB) ||
> >> +                          test_sta_flag(sta, WLAN_STA_MPSP_OWNER) ||
> >> +                          test_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT) ||
> >> +                          !timer_pending(&sta->nexttbtt_timer) ||
> >> +                          time_after(jiffies, sta->nexttbtt_jiffies)) {
> >
> > Are you sure jiffies are good enough? Some systems have HZ=33 or so I
> > think, which makes a jiffy like 30ms.
> 
> Hm, jiffies is what I have available easily. Using the TSF would be 
> obvious but may suffer from delay when obtaining it. Umm... hrtimers again?

I really don't care about your messed up timing stuff here, just
saying :)

johannes