Re: [PATCH v2 00/22] brcmsmac: Tx rework and expanded debug/trace support

[Seth Forshee <seth.forshee@canonical.com>]

On Tue, Nov 20, 2012 at 06:44:08PM +0100, Daniel Wagner wrote:
> Hi Seth,
> 
> On 20.11.2012 15:28, Seth Forshee wrote:
> >On Tue, Nov 20, 2012 at 08:30:10AM +0100, Daniel Wagner wrote:
> >>Hi Seth,
> >>
> >>On 19.11.2012 20:11, Daniel Wagner wrote:
> >>>Works perfectly fine on my machine.
> >>
> >>Well, not really true. Though I am not sure if this what I am seeing
> >>related to your changes. I see following log only when I am using my
> >>home AP. The pattern is that when the connection stop working I see
> >>something like this in the log:
> >>
> >>[ 8735.159091] wlan0: moving STA 1c:c6:3c:1f:50:68 to state 4
> >>[ 8735.197298] wlan0: Rx A-MPDU request on tid 0 result 0
> >>[ 8735.566368] wlan0: Open BA session requested for 1c:c6:3c:1f:50:68 tid 0
> >>[ 8735.573701] wlan0: activated addBA response timer on tid 0
> >>[ 8735.578826] wlan0: switched off addBA timer for tid 0
> >>[ 8735.578834] wlan0: Aggregation is on for tid 0
> >>[ 8749.687530] wlan0: tx session timer expired on tid 0
> >>[ 8749.687558] wlan0: Tx BA session stop requested for 1c:c6:3c:1f:50:68 tid 0
> >>[ 8749.700550] wlan0: Stopping Tx BA session for 1c:c6:3c:1f:50:68 tid 0
> >>
> >>
> >>This is what I do: First establishing a connection, then after a while any
> >>traffic seems stops for a period and sometimes it recovers from that point. If
> >>not a disconnect/connect (using ConnMan) dance fixes the problem.
> >
> >The tx session timer expiring is a result of not having any aggregate
> >transfers in a while. In my testing with iperf I see periods where the
> >transfer seems to stall, but it always recovers. These are less frequent
> >after my patches, but they still happen, and I haven't been able to work
> >out the cause yet. I'm not sure whether these are related to what you're
> >seeing or not.
> >
> >Luckily I've added a bunch of new debug code. Could you make sure you
> >have MAC80211_MESSAGE_TRACING and BRCM_TRACING enabled in your config
> >and collect a trace when this is happening by running:
> >
> >  trace-cmd record -e mac80211 -e mac80211_msg -e brcmsmac \
> >         -e brcmsmac_tx -e brcmsmac_msg
> >
> >This going to collect a lot of data, and you should bump up the trace
> >buffer size to avoid overruns. Once you've got a trace please compress
> >trace.dat and put it along with your dmesg somewhere where I can get at
> >them.
> 
> I hope I got it right. Here are the requested logs:
> 
> http://www.monom.org/misc/brcmsmac/traces/

Looks like you got it right. The period you traced doesn't seem to cover
any of the block ack session timeouts, but I do see this:

[  225.269777] wlan0: release an RX reorder frame due to timeout on earlier frames
[  243.869220] wlan0: unexpected AddBA Req from 1c:c6:3c:1f:50:68 on tid 0
[  243.869233] wlan0: Rx BA session stop requested for 1c:c6:3c:1f:50:68 tid 0 recipient reason: 32
[  243.869250] wlan0: Rx A-MPDU request on tid 0 result 0
[  252.254013] brcmsmac bcma0:0: brcms_c_ampdu_dotxstatus_complete: Pkt tx suppressed, illegal channel possibly 13
<snip repeated messages>
[  259.798966] wlan0: release an RX reorder frame due to timeout on earlier frames
<snip repeated messages>
[  265.193640] wlan0: unexpected AddBA Req from 1c:c6:3c:1f:50:68 on tid 0
[  265.193648] wlan0: Rx BA session stop requested for 1c:c6:3c:1f:50:68 tid 0 recipient reason: 32
[  265.193663] wlan0: Rx A-MPDU request on tid 0 result 0

Does something in this time frame correspond to your loss in
connectivity? The number of packets being sent and received varies some
throughout the trace but generally stays pretty low. It never completely
stops though.

Other than the messages above I don't notice any obvious problems. If
you can pinpoint exactly what range of timestamps corresponds to your
problems I can look a bit closer.

Is this a regression introduced by these patches, or was the connection
with this AP also not working well without them?

Thanks,
Seth