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Message-ID: <da810136f6cf0608167cc8297ce73d11b83974d6.camel@sipsolutions.net>
Subject: Re: [PATCH] wifi: mac80211: Use internal TX queues for all drivers
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Alexander Wetzel <alexander@wetzel-home.de>,
        linux-wireless@vger.kernel.org
Date:   Thu, 29 Sep 2022 22:40:55 +0200
In-Reply-To: <20220926161303.13035-1-alexander@wetzel-home.de>
References: <20220926161303.13035-1-alexander@wetzel-home.de>
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Thanks for doing this!

It's a bit bad timing right now, so I'll only have a chance to look at
this in the next couple of weeks, but that also doesn't matter that much
since 6.0 release is imminent (will likely be Sunday).

Just wanted to comment on this one thing for now:

On Mon, 2022-09-26 at 18:13 +0200, Alexander Wetzel wrote:
> A short look at the in-tree drivers seems to confirm, that mac80211
> drivers are indeed not directly calling netif_stop_queue(). Which is no
> longer undesired but outright wrong after this patch.
> So I *think* we should be fine on that front, too.
>=20

They really couldn't, they don't have (easy) access to the netdev. There
are ways of getting to the netdev, but they're (intentionally) difficult
and doing that would've been wrong even previously since mac80211 has
its own reasons for stopping netdev queues sometimes.

So unless a driver is already broken, this can't be an issue.

> I did not try very hard to identify now obsolete code fragments and
> kept this as simple as possible.

That's nice enough for now, do you want to do follow-ups to clean up
more?

> I've also have a rough draft to move PS (multicast and unicast) to iTXQ
> we should look at later. That seems to be way more invasive than what we
> do here. But once PS also has been sorted out moving everything to iTXQ
> should be straight forward.

Ohhh! I'm excited about this :-)

johannes