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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Sun, 27 Aug 2017 14:42:11 -0700
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Subject: Re: [PATCH 2/2 v2] sched/wait: Introduce lock breaker in wake_up_page_bit
To: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>,
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On Sun, Aug 27, 2017 at 2:40 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> End result: page is unlocked, CPU3 is waiting, nothing will wake CPU3 up.

Not CPU3. CPU3 was the waker. It's thread 2 that is waiting and never
got woken up, of course.

Other than that, the scenario still looks real to me.

Ideas?

                 Linus