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Date:   Thu, 25 Feb 2021 23:23:18 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Paul E. McKenney" <paulmck@kernel.org>
Cc:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        rcu <rcu@vger.kernel.org>, Josh Triplett <josh@joshtriplett.org>,
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        Lai Jiangshan <jiangshanlai@gmail.com>,
        "Joel Fernandes, Google" <joel@joelfernandes.org>
Subject: Re: tasks-trace RCU: question about grace period forward progress
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On Thu, Feb 25, 2021 at 10:33:21AM -0800, Paul E. McKenney wrote:
> One question for Peter...  Does each and every context switch imply a
> full barrier?

Yes, also see the smp_mb__after_spinlock() in __schedule() :-)