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Date:   Tue, 25 Jun 2019 14:25:16 +0200
From:   Frederic Weisbecker <frederic@kernel.org>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     "Paul E. McKenney" <paulmck@linux.ibm.com>,
        linux-kernel@vger.kernel.org, mingo@redhat.com, tglx@linutronix.de
Subject: Re: [PATCH] time/tick-broadcast: Fix tick_broadcast_offline()
 lockdep complaint
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On Tue, Jun 25, 2019 at 09:51:39AM +0200, Peter Zijlstra wrote:
> On Tue, Jun 25, 2019 at 02:43:00AM +0200, Frederic Weisbecker wrote:
> > Yeah, unfortunately there is no atomic_add_not_zero_return().
> 
> There is atomic_fetch_add_unless().

Ah, that could work!