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Subject: Re: [RFC 3/6] mac80211: add a TXQ for other powersave-buffered frames
To: Johannes Berg <johannes@sipsolutions.net>,
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From: Ben Greear <greearb@candelatech.com>
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Date: Mon, 26 Jun 2017 07:15:13 -0700
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On 06/26/2017 04:00 AM, Johannes Berg wrote:
> On Fri, 2017-06-23 at 05:27 -0700, Ben Greear wrote:
>
>> I don't understand the code well enough to know if this matters or
>> not, but the ath10k wave-2 stuff has some txq prefetch logic in the
>> firmware (and support in the driver).  But, it doesn't prefetch for
>> the mgt tid as far as I can tell.  It somehow all mostly works
>> anyway, but possibly this would have some effect on your
>> changes.  wave-1 (QCA 9880, etc) doesn't do txq prefetch at all.  Any
>> tricky changes to this logic would need to test with both chipsets.
>
> I don't think this matters. The issue at hand is that the driver still
> relies on mac80211 buffering.
>
> This *can* be solved, even in this piece of code I inserted here, but
> it'd have to keep state about the queues and then insert some hooks
> elsewhere. I'm pretty sure I can solve that, but don't have the time
> (or even hardware) to test this (easily, I have ath10k in a few
> routers, but ...).

What/how is it relying on buffering?

I'd be happy to send you plenty of ath10k mini-pcie NICs if that would help.

Just let me know.

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com