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Date: Tue, 17 Mar 2015 04:56:08 -0700
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        linux-kernel@vger.kernel.org,
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        Thomas Gleixner <tglx@linutronix.de>,
        David Howells <dhowells@redhat.com>, Nick Piggin <npiggin@kernel.dk>
Subject: Re: [RFC PATCH] sys_membarrier(): system/process-wide memory barrier
 (x86) (v12)
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On Tue, Mar 17, 2015 at 07:30:59AM +0100, Peter Zijlstra wrote:
> On Tue, Mar 17, 2015 at 01:45:25AM +0000, Mathieu Desnoyers wrote:

[ . . . ]

> > Then we can add
> > the expedited-private implementation after rq->curr becomes
> > available through RCU.
> 
> Yeah, or not at all; I'm still trying to get Paul to remove the
> expedited nonsense from the kernel RCU bits; and now you want it in
> userspace too :/

Well, the expedited RCU primitives got added for some use cases, and
those use cases are still with us.  ;-)

							Thanx, Paul