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Date: Sat, 27 Aug 2016 20:27:42 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Waiman Long <waiman.long@hpe.com>, Jason Low <jason.low2@hpe.com>,
        Davidlohr Bueso <dave@stgolabs.net>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Ding Tianhong <dingtianhong@huawei.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Will Deacon <Will.Deacon@arm.com>, Ingo Molnar <mingo@redhat.com>,
        Imre Deak <imre.deak@intel.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Tim Chen <tim.c.chen@linux.intel.com>,
        "Paul E. McKenney" <paulmck@us.ibm.com>, jason.low2@hp.com
Subject: Re: [RFC][PATCH 0/3] locking/mutex: Rewrite basic mutex
Message-ID: <20160827182742.GA8248@gmail.com>
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* Peter Zijlstra <peterz@infradead.org> wrote:

> Its because the mutex wasn't quite exclusive enough :-) If you let in multiple 
> owner, like with that race you found, you get big gains in throughput ...

Btw., do we know which mutex that was?

That it didn't crash with a full AIM run suggests that whatever it is protecting 
it could probably be parallelized some more while still having a mostly working 
kernel! ;-)

Thanks,

	Ingo