Re: [PATCH 6/6] mac80211: stop queues before rate control updation

["John W. Linville" <linville@tuxdriver.com>]

On Tue, Jun 07, 2011 at 08:39:57AM +0000, Manoharan, Rajkumar wrote:
> > > On Mon, 2011-06-06 at 14:44 -0400, John W. Linville wrote:
> > 
> > > > During the channel type change, the pending tx frames in hw queues are dropped by hw config.
> > > > But before updating rate control, the packets can be queued again with older HT rates.
> > > > This contradicts with hw config mode and sometimes is causing baseband issues. This issue
> > > > was observed only on flooding uplink traffic. To ensure that the frames are always xmitted with
> > > > updated rates, the queues are stopped before hw config and waken up after rc updation.
> >> 
> > > Johannes, do you find this explanation satisfactory (perhaps with
> > > some new queue stop reason definition)?
> > 
> > No, it doesn't address the fact that any packet that is pending will
> > still be processed -- as I said before, the stop doesn't include a
> > flush.
> 
> Yes. I agree. Without flushing, still the packets can choose wrong rates. I missed that.
> But I assumed that it would be better to stop queues before rc update. Thus we can avoid revisiting
> the queued frames chosen with older (this case ht40) rate after rc changes. And fixing at mac80211 would help
> to other rate controls too.

OK, it seems like this isn't getting resolved quickly.  I'm going to
revert it for now, and hope for a more widely acceptable solution soon.

John
-- 
John W. Linville		Someday the world will need a hero, and you
linville@tuxdriver.com			might be all we have.  Be ready.