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Message-ID: <b7b09926e76112e79d0683089c85cad894d8d6de.camel@sipsolutions.net>
Subject: Re: [RFC PATCH 2/2] mac80211: use the new drop reasons
 infrastructure
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     linux-wireless@vger.kernel.org, netdev@vger.kernel.org
Date:   Thu, 30 Mar 2023 10:14:43 +0200
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On Wed, 2023-03-29 at 21:06 -0700, Jakub Kicinski wrote:
> On Wed, 29 Mar 2023 23:56:31 +0200 Johannes Berg wrote:
> > > +	drop_reasons_unregister_subsys(SKB_DROP_REASON_SUBSYS_MAC80211_MONI=
TOR);
> > > +	drop_reasons_unregister_subsys(SKB_DROP_REASON_SUBSYS_MAC80211_UNUS=
ABLE);
> > > +
> > >  	rcu_barrier(); =20
> >=20
> > This is making me think that perhaps we don't want synchronize_rcu()
> > inside drop_reasons_unregister_subsys(), since I have two now and also
> > already have an rcu_barrier() ... so maybe just document that it's
> > needed?
>=20
> premature optimization? some workload is reloading mac80211 in a loop?

Yeah, true, nobody is going to do that :-)

Let's leave it this way.

johannes