From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rick Jones <rick.jones2@hpe.com>
Subject: Re: spin_lock cause ?
Date: Wed, 1 Jun 2016 11:53:20 -0700
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To: M Kelly <mark.kelly@lexisnexis.com>, linux-perf-users@vger.kernel.org

On 06/01/2016 11:49 AM, M Kelly wrote:
> So that is helpful.
> I do not understand the system_call_fastpath->futex->_spin_lock part yet,
> but that is a separate issue!

Just a guess, but if your application is using threads, contention on 
the synchonrization primitives you use to keep things straight can 
end-up punting to the kernel.

rick jones