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Date: Tue, 28 Feb 2017 10:48:53 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Chris Wilson <chris@chris-wilson.co.uk>
Cc: linux-kernel@vger.kernel.org, Fengguang Wu <fengguang.wu@intel.com>
Subject: Re: [PATCH] locking/ww_mutex: Replace cpu_relax with cond_resched
 for tests
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References: <20170228035924.hqckycv6at4sfzyc@wfg-t540p.sh.intel.com>
 <20170228094011.2595-1-chris@chris-wilson.co.uk>
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On Tue, Feb 28, 2017 at 09:40:11AM +0000, Chris Wilson wrote:
> When busy-spinning on a ww_mutex_trylock(), we depend upon the other
> thread advancing and releasing the lock. This can not happen on a single
> CPU unless we relinquish it.

Thanks, do you have any clue about those other ww-mutex test fails? So
far I've not had much luck poking at them.