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Date:   Thu, 6 Apr 2023 08:56:29 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     "Paul E. McKenney" <paulmck@kernel.org>
Cc:     Herbert Xu <herbert@gondor.apana.org.au>,
        Alexander Duyck <alexander.duyck@gmail.com>,
        Heiner Kallweit <hkallweit1@gmail.com>, davem@davemloft.net,
        netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com
Subject: Re: [PATCH net-next 1/3] net: provide macros for commonly copied
 lockless queue stop/wake code
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On Thu, 6 Apr 2023 08:45:10 -0700 Paul E. McKenney wrote:
> > Starting the queue only happens from softirq (I hope) and stopping 
> > can happen from any context. So we're risking false-starts again.
> > I think this puts to bed any hope of making this code safe against
> > false-starts with just barriers :(  
> 
> Is it possible to jam all the relevant state into a single variable?
> (I believe that that answer is "no", but just in case asking this question
> inspires someone to come up with a good idea.)

Not in any obvious way, half of the state is driver-specific the other
half is flags maintained by the core :S