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Date:   Wed, 23 Sep 2020 17:29:52 +0200
From:   Frederic Weisbecker <frederic@kernel.org>
To:     "Paul E. McKenney" <paulmck@kernel.org>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Joel Fernandes <joel@joelfernandes.org>,
        Josh Triplett <josh@joshtriplett.org>
Subject: Re: [RFC PATCH 07/12] rcu: Shutdown nocb timer on de-offloading
Message-ID: <20200923152951.GC31465@lenoir>
References: <20200921124351.24035-1-frederic@kernel.org>
 <20200921124351.24035-8-frederic@kernel.org>
 <20200922001756.GP29330@paulmck-ThinkPad-P72>
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On Mon, Sep 21, 2020 at 05:17:56PM -0700, Paul E. McKenney wrote:
> On Mon, Sep 21, 2020 at 02:43:46PM +0200, Frederic Weisbecker wrote:
> > Make sure the nocb timer can't fire anymore before we reach the final
> > de-offload state. Spuriously waking up the GP kthread is no big deal but
> > we must prevent from executing the timer callback without nocb locking.
> 
> If we had just the previous patch and not this patch, would things break?
> Or are you relying on the fact that there is not yet a connection to
> userspace controls for this functionality?

Exactly it shouldn't break because only the last patch makes the code
eventually used.

Thanks.