Chenchong's work on net80211_ratectl

[Chenchong Qin]

OK!

I'll post it later. :)

Thanks!

Chenchong


On Thu, Sep 19, 2013 at 9:38 AM, Adrian Chadd <adrian at freebsd.org> wrote:

> Sweet, thanks!
>
> Please post the final and some sample output from ifconfig and sysctl
> somewhere so we can take a more detailed look.
>
> I'll be travelling over the next few days; I'll try to get it all
> finalised later this month.
>
> Thanks again! Great work!
>
>
> -adiran
>
>
>
> On 16 September 2013 02:32, Chenchong Qin <qinchenchong at gmail.com> wrote:
>
>> Hi!
>>
>> In this update, I update ieee80211_sample and complete
>> ieee80211_ratectl_none templete.
>>
>> * rename ieee80211_rc_sample* to ieee80211_sample*. this seems to be more
>> harmonious.
>> * modify ieee80211_sample to let it use the latest net80211-ratectl
>> features.
>> * fix some errors in ieee80211_sample.
>> * complete the ieee80211_ratectl_none templete with newly added
>> net80211-ratectl functions.
>>
>> You will need to add wlan_sample to sys/conf/files to make
>> ieee80211_sample compiled.
>>
>> Thanks!
>>
>> Chenchong
>>
>>
>> On Mon, Sep 16, 2013 at 5:08 PM, Chenchong Qin <qinchenchong at gmail.com>wrote:
>>
>>> Hi!
>>>
>>> Yes!
>>>
>>> Here is a fresh debug log.
>>>
>>> @adrian you may received many copies of this message because I got the
>>> "Message body too large" limit of freebsd-wireless list. So I compress
>>> the
>>> log file and re-send it. Sorry to be confused. :)
>>>
>>> Thanks!
>>>
>>> Chenchong
>>>
>>>
>>> On Mon, Sep 16, 2013 at 4:40 PM, Adrian Chadd <adrian at freebsd.org>wrote:
>>>
>>>> Sweet!
>>>>
>>>> Does this work on your AR9227? Can you provide some example output?
>>>>
>>>>
>>>> -a
>>>>
>>>>
>>>> On 14 September 2013 21:08, Chenchong Qin <qinchenchong at gmail.com>wrote:
>>>>
>>>>> Hi!
>>>>>
>>>>> Yes, a call to ieee80211_ratectl_rc_info_set() is needed. To make
>>>>> other drivers work, the __init__ and __findrate__ parts also need to be
>>>>> adapted.
>>>>> When initialize the ratectl state, a cap flag must be properly set and
>>>>> feed to ieee80211_ratectl_init().  __findrate__ part should be repalced
>>>>> with our
>>>>> ieee80211_ratectl_rates().
>>>>>
>>>>> I've added  ieee80211_ratectl_rc_info_get() to be used to get the
>>>>> ieee80211_rc_info. If found the tag, use it; if not, add a new one and use
>>>>> it. Then we don't
>>>>> need to free it explicitly (the tag is freed when associated mbuf is
>>>>> freed) and this interface is unified to both __findrate__ and
>>>>> __complete__.
>>>>>
>>>>> Thanks!
>>>>>
>>>>> Chenchong
>>>>>
>>>>>
>>>>> On Sat, Sep 14, 2013 at 11:21 PM, Adrian Chadd <adrian at freebsd.org>wrote:
>>>>>
>>>>>> Ah, cool! I see you've only just made the other drivers compile;
>>>>>> what's required to make them work? i guess a call
>>>>>> to ieee80211_ratectl_rc_info_set() ?
>>>>>>
>>>>>> Maybe you should add a ieee80211_ratectl_rc_info_set_mbuf() helper
>>>>>> that does the "lookup tag; if one exists use it else use a temporary one"
>>>>>> code that you put in if_ath.c, if_ath_tx.c.
>>>>>>
>>>>>> Other than that, this is looking very good! thankyou!
>>>>>>
>>>>>>
>>>>>> -adrian
>>>>>>
>>>>>>
>>>>>>
>>>>>> On 13 September 2013 20:52, Chenchong Qin <qinchenchong at gmail.com>wrote:
>>>>>>
>>>>>>> Hi,
>>>>>>>
>>>>>>> Here is latest update. Per-device ratectl statistics is implemented
>>>>>>> in ath and attached when ath is attaching.
>>>>>>>
>>>>>>> Thanks!
>>>>>>>
>>>>>>> Chenchong
>>>>>>>
>>>>>>>
>>>>>>> On Sat, Sep 14, 2013 at 3:37 AM, Adrian Chadd <adrian at freebsd.org>wrote:
>>>>>>>
>>>>>>>> Sweet, thanks!
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> -adrian
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> On 13 September 2013 09:11, Chenchong Qin <qinchenchong at gmail.com>wrote:
>>>>>>>>
>>>>>>>>> Hi!
>>>>>>>>>
>>>>>>>>> Here is some updates.
>>>>>>>>>
>>>>>>>>> Another member is added to ieee80211_rc_info to record value of
>>>>>>>>> the maximum aggregate size. Then, in aggregation scenario, ratectl algo can
>>>>>>>>> inform aggregation selection code of proper maximum aggregate size.
>>>>>>>>>
>>>>>>>>> Per-vap ratectl statistics is exported through sysctl. When
>>>>>>>>> ieee80211_ratectl_init() is called, this statistics api is attached. It's
>>>>>>>>> convenient to implement the per-device api -- just traverse the vap list
>>>>>>>>> and call per-vap api for each vap. But, we know that ratectl of net80211
>>>>>>>>> provides service to vap-granularity object, not to device directly. So, is
>>>>>>>>> it more suitable to implement the per-device api in device driver (i.e.
>>>>>>>>> attach per-device api when attaching the device)?
>>>>>>>>>
>>>>>>>>> Code will be posted later.
>>>>>>>>>
>>>>>>>>> Thanks!
>>>>>>>>>
>>>>>>>>> Chenchong
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> On Thu, Sep 12, 2013 at 2:05 AM, Adrian Chadd <adrian at freebsd.org>wrote:
>>>>>>>>>
>>>>>>>>>> Hi,
>>>>>>>>>>
>>>>>>>>>> For now, yes, you have to assume that you won't always get a
>>>>>>>>>> response for a rate lookup. The buffer may be sent with NOACK set, it may
>>>>>>>>>> be deleted during a channel change or scan, etc.
>>>>>>>>>>
>>>>>>>>>> And yes - the rate control lookup stuff for aggregate frames is a
>>>>>>>>>> bit messy. It would be nice for the rate control code to return the rate
>>>>>>>>>> _and_ the maximum aggregate size, in case the aggregation selection wants
>>>>>>>>>> to cap how long frames are at the given choice.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> -adrian
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On 11 September 2013 10:29, Chenchong Qin <qinchenchong at gmail.com
>>>>>>>>>> > wrote:
>>>>>>>>>>
>>>>>>>>>>> Hi!
>>>>>>>>>>>
>>>>>>>>>>> I've added some aggregation support here!
>>>>>>>>>>>
>>>>>>>>>>> At first I intend to pass subframe informations(nframes,
>>>>>>>>>>> per-subframe length etc.)
>>>>>>>>>>> to the ratectl api. But it seems to be a paradox that rate
>>>>>>>>>>> lookup must be performed
>>>>>>>>>>> before the ampdu is formed (aggregation limit based on the rate
>>>>>>>>>>> control decision
>>>>>>>>>>> is need) and subframe informations can be obtain only after the
>>>>>>>>>>> ampdu is formed.
>>>>>>>>>>> So, I add a new ieee80211_rc_info flag to ieee80211_ratectl to
>>>>>>>>>>> let it distinguish
>>>>>>>>>>> aggregation and non-aggregation scenarios. If rate lookup is
>>>>>>>>>>> called in an aggregation
>>>>>>>>>>> scenario, this flag is set. Then, ratectl algo knows that it's
>>>>>>>>>>> now finding rates for an
>>>>>>>>>>> ampdu and the framelen which records len of the first frame can
>>>>>>>>>>> be ignored. When
>>>>>>>>>>> it comes to complete period, tx status that shows number of
>>>>>>>>>>> subframes been sent
>>>>>>>>>>> and number of subframes been successfully received is passed to
>>>>>>>>>>> the ratectl api.
>>>>>>>>>>>
>>>>>>>>>>> I also get a question here - whether one tx that doesn't perform
>>>>>>>>>>> rate lookup will call
>>>>>>>>>>> the complete procedure?
>>>>>>>>>>>
>>>>>>>>>>> Thanks!
>>>>>>>>>>>
>>>>>>>>>>> Chenchong
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> On Sun, Sep 8, 2013 at 11:18 PM, Chenchong Qin <
>>>>>>>>>>> qinchenchong at gmail.com> wrote:
>>>>>>>>>>>
>>>>>>>>>>>> Hi!
>>>>>>>>>>>>
>>>>>>>>>>>> I've added the common ratectl state as an mbuf tag!
>>>>>>>>>>>>
>>>>>>>>>>>> After days of frustration (compile errors, boot failed, kernel
>>>>>>>>>>>> panics, suddenly kernel freezing...), it seems that ath now can use
>>>>>>>>>>>> 11n-aware net80211 ratectl api to do rate control. Attachment[0] is the
>>>>>>>>>>>> diff of modifications to dev/ath. Changes to net80211 is minor this time.
>>>>>>>>>>>> Just add some debug msgs to it. Please reference my gsoc svn
>>>>>>>>>>>> repo <https://svnweb.freebsd.org/socsvn/soc2013/ccqin/head/>.
>>>>>>>>>>>>
>>>>>>>>>>>> It's worth mentioning that sometimes the kernel will "freezing"
>>>>>>>>>>>> (it looks like all things stop working, screen is freezing, keyboard and
>>>>>>>>>>>> mouse are not responding) after wireless stuff start working for a while.
>>>>>>>>>>>> At first, I consider it caused by my modification to ath. But this strange
>>>>>>>>>>>> thing can also happen in a head kernel (r255382). Attachment[1] is some
>>>>>>>>>>>> useful messages just before it happens. By the way, I use a AR9227 device.
>>>>>>>>>>>>
>>>>>>>>>>>> And, I found that, for aggregation scenario, ath gathers tx
>>>>>>>>>>>> information and update the ratectl states. So, what we can do to net80211
>>>>>>>>>>>> to let it support aggregation?
>>>>>>>>>>>>
>>>>>>>>>>>> Thanks!
>>>>>>>>>>>>
>>>>>>>>>>>> Chenchong
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> On Tue, Sep 3, 2013 at 9:29 AM, Chenchong Qin <
>>>>>>>>>>>> qinchenchong at gmail.com> wrote:
>>>>>>>>>>>>
>>>>>>>>>>>>> OK!
>>>>>>>>>>>>>
>>>>>>>>>>>>> Thanks! :-)
>>>>>>>>>>>>>
>>>>>>>>>>>>> Chenchong
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>> On Tue, Sep 3, 2013 at 1:56 AM, Adrian Chadd <
>>>>>>>>>>>>> adrian at freebsd.org> wrote:
>>>>>>>>>>>>>
>>>>>>>>>>>>>> Hi!
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> You can declare an mbuf tag and use that. Look at M_TXCB in
>>>>>>>>>>>>>> net80211 and how mbuf tags are added.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> I've long thought about adding a net80211 mbuf tag to
>>>>>>>>>>>>>> represent -all- of the tx related state - TX callback, rate control, rate
>>>>>>>>>>>>>> completion, aggregation state, retry count, etc. That way all the drivers
>>>>>>>>>>>>>> can use it.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> -adrian
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>