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Date: Wed, 10 May 2017 13:15:28 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>,
        LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@kernel.org>,
        Sebastian Siewior <bigeasy@linutronix.de>
Subject: Re: [patch V2 24/24] cpu/hotplug: Convert hotplug locking to percpu
 rwsem
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On Wed, 10 May 2017 12:30:57 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

 
> I finally got some time to look at this. I'm looking at your commit:
> 
> commit b53e5129c4c7ab47ec4f709fd8f5784ca45fb46d
> Author: Thomas Gleixner <tglx@linutronix.de>
> Date:   Sun Apr 23 12:17:13 2017 +0200
> 
>     trace/perf: Cure hotplug lock ordering issues
> 
> What were the circular locking dependencies that were uncovered.
> 
> event_mutex could possibly be broken up, if that helps. It sorta became
> a catch all for various modifications to tracing.
> 

I checked out the commit before this and started playing with it. I see
some of the issues now. I'll look more into it.

-- Steve