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Date: Wed, 5 Jun 2024 18:52:18 +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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	hernan.poncedeleon@huaweicloud.com,
	jonas.oberhauser@huaweicloud.com
Subject: Re: [PATCH v2] tools/memory-model: Document herd7 (abstract)
 representation
Message-ID: <ZmCXwjX/Rx7zKWpj@andrea>
References: <20240605134918.365579-1-parri.andrea@gmail.com>
 <037bc316-3e8c-4748-bade-ffdad4239646@rowland.harvard.edu>
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> I wonder if we really need a special notation for lk-rmw.  Is anything 
> wrong with using the normal rmw notation for these links?

I don't think we need the special notation: in fact, herd7 doesn't know
anything about these lk-rmw or rmw links between lock events until after
tools/memory-model/ (the .cat file) has established such links cf.

  (* Link Lock-Reads to their RMW-partner Lock-Writes *)
  let lk-rmw = ([LKR] ; po-loc ; [LKW]) \ (po ; po)
  let rmw = rmw | lk-rmw

I was trying to be informative (since that says "lk-rmw is a subrelation
of rmw) but, in order to be faithful to the scope of this document (herd
representation), the doc should really just indicate LKR ->po LKW.

Thoughts?

  Andrea