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Date:   Thu, 29 Aug 2019 09:09:46 -0700
From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     Joel Fernandes <joel@joelfernandes.org>
Cc:     linux-kernel@vger.kernel.org,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Josh Triplett <josh@joshtriplett.org>, kernel-team@android.com,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        linux-doc@vger.kernel.org,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Mauro Carvalho Chehab <mchehab+samsung@kernel.org>,
        rcu@vger.kernel.org, Steven Rostedt <rostedt@goodmis.org>,
        luto@kernel.org
Subject: Re: [RFC v1 2/2] rcu/tree: Remove dynticks_nmi_nesting counter
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On Thu, Aug 29, 2019 at 10:43:55AM -0400, Joel Fernandes wrote:

[ . . . ]

> Paul, do we also nuke rcu_eqs_special_set()?  Currently I don't see anyone
> using it. And also remove the bottom most bit of dynticks?
> 
> Also what happens if a TLB flush broadcast is needed? Do we IPI nohz or idle
> CPUs are the moment?
> 
> All of this was introduced in:
> b8c17e6664c4 ("rcu: Maintain special bits at bottom of ->dynticks counter")

Adding Andy Lutomirski on CC.

Andy, is this going to be used in the near term, or should we just get
rid of it?

							Thanx, Paul