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Date: Mon, 27 May 2024 10:07:06 +0200
From: Andrea Parri <parri.andrea@gmail.com>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: will@kernel.org, peterz@infradead.org, boqun.feng@gmail.com,
	npiggin@gmail.com, dhowells@redhat.com, j.alglave@ucl.ac.uk,
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	dlustig@nvidia.com, joel@joelfernandes.org,
	linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
	hernan.poncedeleon@huaweicloud.com,
	jonas.oberhauser@huaweicloud.com
Subject: Re: [PATCH] tools/memory-model: Document herd7 (internal)
 representation
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References: <20240524151356.236071-1-parri.andrea@gmail.com>
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> It turns out the problem lies in the way lock.cat tries to calculate the 
> rf relation for RU events (a spin_is_locked() that returns False).  The 
> method it uses amounts to requiring that such events must read from the 
> lock's initial value or an LU event (a spin_unlock()) in a different 
> thread.  This clearly is wrong, and glaringly so in this litmus test 
> since there are no other threads!
> 
> A patch to fix the problem and reorganize the code a bit for greater 
> readability is below.  I'd appreciate it if people could try it out on 
> various locking litmus tests in our archives.

Thanks for the quick solution, Alan.  The results from our archives look
good.

  Andrea