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Date:   Tue, 29 Sep 2020 11:19:03 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Paul McKenney <paulmck@kernel.org>, linux-kernel@vger.kernel.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@kernel.org>, kim.phillips@amd.com
Subject: Re: [PATCH] rcu,ftrace: Fix ftrace recursion
Message-ID: <20200929111903.3e3e8c23@gandalf.local.home>
In-Reply-To: <20200929144953.GP2628@hirez.programming.kicks-ass.net>
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        <20200929103620.06762622@gandalf.local.home>
        <20200929144953.GP2628@hirez.programming.kicks-ass.net>
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On Tue, 29 Sep 2020 16:49:53 +0200
Peter Zijlstra <peterz@infradead.org> wrote:

> On Tue, Sep 29, 2020 at 10:36:20AM -0400, Steven Rostedt wrote:
> 
> > > +notrace bool rcu_is_watching(void)
> > >  {
> > >  	bool ret;
> > >    
> > 
> > I think the patch I suggested is more suitable.  
> 
> Both, with only your patch we'd still take the pointless mcount call,
> which is then pure overhead.

Yep, and I stated the same thing to Paul ;-)

-- Steve