Re: [Make-wifi-fast] [PATCH v4] ath9k: Switch to using mac80211 intermediate software queues.

[Kalle Valo <kvalo@codeaurora.org>]

Toke Høiland-Jørgensen <toke@toke.dk> writes:

>>>> This is great work but due to the regressions I'm not sure if this
>>>> will be ready for 4.9. To get more testing time I wonder if we should
>>>> wait for 4.10? IMHO applying this in the end of the cycle is too risky
>>>> and we should try to maximise the time linux-next by applying this
>>>> just after -rc1 is released.
>>>>
>>>> Thoughts?
>>>
>>> Well, now that we understand what is causing the throughput regressions,
>>> fixing them should be fairly straight forward (yeah, famous last words,
>>> but still...). I already have a patch for the fast path and will go poke
>>> at the slow path next. It'll probably require another workaround or two,
>>> so I guess it won't be the architecturally clean ideal solution; but it
>>> would make it possible to have something that works for 4.9 and then
>>> iterate for a cleaner design for 4.10.
>>
>> But if we try to rush this to 4.9 it won't be in linux-next for long. We
>> are now in -rc3 and let's say that the patches are ready to apply in two
>> weeks. That would leave us only two weeks of -next time before the merge
>> window, which I think is not enough for a controversial patch like this
>> one. There might be other bugs lurking which haven't been found yet.
>
> What, other hidden bugs? Unpossible! :)

Yeah, right ;)

> Would it be possible to merge the partial solution (which is ready now,
> basically) and fix the slow path in a separate patch later?

What do you mean with partial solution? You mean ath9k users would
suffer from regressions until they are fixed? We can't do that.

> (Just spit-balling here; I'm still fairly new to this process. But I am
> concerned that we'll hit a catch-22 where we can't get wider testing
> before it's "ready" and we can't prove that it's "ready" until we've had
> wider testing...)

I understand your point, but I don't want to rush this to 4.9 and then
start getting lots of bug reports and eventually forced to revert it. If
we just found a new serious regression the chances are that there are
more lurking somewhere and this patch is just not ready yet.

-- 
Kalle Valo