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Date: Sun, 14 Dec 2014 12:23:40 -0800
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Ingo Molnar <mingo@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Subject: Re: [PATCH 1/3] tracepoints: Do not use call_rcu_sched() before
 early_initcall()
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On Sun, Dec 14, 2014 at 01:25:56PM -0500, Steven Rostedt wrote:
> On Sun, 14 Dec 2014 10:18:35 -0800
> "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> wrote:
> 
> > > With your feed back, and because I would like this to go into 3.19, I
> > > would like to keep the current patch as is (with the read_mostly
> > > update, which I'm currently testing). We can always change it later
> > > after call_rcu() has been changed.
> > 
> > Completely agreed!  ;-)
> 
> For this late in the game, we need to play it safe.
> 
> I got rid of my tracepoint patch and moved trace_init() to after
> rcu_init(), which I think is good enough for Thomas. Thomas?
> 
> I'll start testing that now.

That should work as well.

> Later, if you could add a rcu_init() version that lets us call
> call_rcu_sched() just after mm_init() then we could move trace_init()
> up a bit more.

OK, will put something together for that.  Good to hear that this is
not needed indefinitely early -- that would be a bit harder.  ;-)

							Thanx, Paul