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Date: Thu, 2 Jul 2015 20:35:57 +0200
From: Ingo Molnar <mingo@kernel.org>
To: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>, josh@joshtriplett.org,
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Subject: Re: [PATCH RFC tip/core/rcu 0/5] Expedited grace periods encouraging
 normal ones
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* Paul E. McKenney <paulmck@linux.vnet.ibm.com> wrote:

> > And it's not like it's that hard to stem the flow of algorithmic sloppiness at 
> > the source, right?
> 
> OK, first let me make sure that I understand what you are asking for:
> 
> 1.	Completely eliminate synchronize_rcu_expedited() and
> 	synchronize_sched_expedited(), replacing all uses with their
> 	unexpedited counterparts.  (Note that synchronize_srcu_expedited()
> 	does not wake up CPUs, courtesy of its read-side memory barriers.)
> 	The fast-boot guys are probably going to complain, along with
> 	the networking guys.
> 
> 2.	Keep synchronize_rcu_expedited() and synchronize_sched_expedited(),
> 	but push back hard on any new uses and question any existing uses.
> 
> 3.	Revert 74b51ee152b6 ("ACPI / osl: speedup grace period in
> 	acpi_os_map_cleanup").
> 
> 4.	Something else?

I'd love to have 1) but 2) would be a realistic second best option? ;-)

Thanks,

	Ingo