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Date: Wed, 13 Jul 2016 14:08:57 -0700
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>, John Stultz <john.stultz@linaro.org>,
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        Rom Lemarchand <romlem@google.com>, Colin Cross <ccross@google.com>,
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Subject: Re: Severe performance regression w/ 4.4+ on Android due to cgroup
 locking changes
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On Wed, Jul 13, 2016 at 10:57:12PM +0200, Peter Zijlstra wrote:
> On Wed, Jul 13, 2016 at 01:52:11PM -0700, Paul E. McKenney wrote:
> > Not a particularly real-time-friendly fix, but certainly a good check
> > on our various assumptions.
> 
> Not only RT, but also HPC and all the other RDMA userspace polling
> freaks ;-)

If Tejun's lglock-like approach doesn't pan out, then it would quite
easy to make a boot parameter that selected expedited vs. non-expedited
behavior.

							Thanx, Paul