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Date:   Wed, 29 Mar 2023 21:06:33 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Johannes Berg <johannes@sipsolutions.net>
Cc:     linux-wireless@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: [RFC PATCH 2/2] mac80211: use the new drop reasons
 infrastructure
Message-ID: <20230329210633.39cca656@kernel.org>
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On Wed, 29 Mar 2023 23:56:31 +0200 Johannes Berg wrote:
> > +	drop_reasons_unregister_subsys(SKB_DROP_REASON_SUBSYS_MAC80211_MONITOR);
> > +	drop_reasons_unregister_subsys(SKB_DROP_REASON_SUBSYS_MAC80211_UNUSABLE);
> > +
> >  	rcu_barrier();  
> 
> 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?

premature optimization? some workload is reloading mac80211 in a loop?