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Message-ID: <99df6853f2eb541773435053983ab466b88b0d74.camel@redhat.com>
Subject: Re: [PATCH RT v2 2/3] sched: migrate_enable: Use sleeping_lock to
 indicate involuntary sleep
From:   Scott Wood <swood@redhat.com>
To:     paulmck@linux.ibm.com
Cc:     Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org,
        Joel Fernandes <joel@joelfernandes.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Clark Williams <williams@redhat.com>
Date:   Thu, 22 Aug 2019 20:21:34 -0500
In-Reply-To: <20190821233555.GV28441@linux.ibm.com>
References: <20190821231906.4224-1-swood@redhat.com>
         <20190821231906.4224-3-swood@redhat.com>
         <20190821233555.GV28441@linux.ibm.com>
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On Wed, 2019-08-21 at 16:35 -0700, Paul E. McKenney wrote:
> On Wed, Aug 21, 2019 at 06:19:05PM -0500, Scott Wood wrote:
> > Without this, rcu_note_context_switch() will complain if an RCU read
> > lock is held when migrate_enable() calls stop_one_cpu().
> > 
> > Signed-off-by: Scott Wood <swood@redhat.com>
> 
> I have to ask...  Both sleeping_lock_inc() and sleeping_lock_dec() are
> no-ops if not CONFIG_PREEMPT_RT_BASE?

Yes.

-Scott