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Date:   Thu, 29 Nov 2018 19:13:12 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Waiman Long <longman@redhat.com>
Cc:     Yongji Xie <elohimes@gmail.com>, mingo@redhat.com,
        will.deacon@arm.com, linux-kernel@vger.kernel.org,
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        yuanlinsi01@baidu.com, nixun@baidu.com, lilin24@baidu.com,
        Davidlohr Bueso <dave@stgolabs.net>
Subject: Re: [RFC] locking/rwsem: Avoid issuing wakeup before setting the
 reader waiter to nil
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On Thu, Nov 29, 2018 at 12:58:26PM -0500, Waiman Long wrote:
> OK, you convinced me. However, that can still lead to anonymous wakeups
> that can be problematic if it happens in certain places. Should we try
> to reduce anonymous wakeup as much as possible?

No, we should at all times accept and expect spurious wakeups.