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Date: Wed, 5 Jun 2024 21:48:12 +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: <ZmDA/HLMi8DWrgCk@andrea>
References: <20240605134918.365579-1-parri.andrea@gmail.com>
 <037bc316-3e8c-4748-bade-ffdad4239646@rowland.harvard.edu>
 <ZmCXwjX/Rx7zKWpj@andrea>
 <010bd7e9-de81-4ff7-8532-18c41318123e@rowland.harvard.edu>
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In-Reply-To: <010bd7e9-de81-4ff7-8532-18c41318123e@rowland.harvard.edu>

On Wed, Jun 05, 2024 at 01:55:08PM -0400, Alan Stern wrote:
> On Wed, Jun 05, 2024 at 06:52:18PM +0200, Andrea Parri wrote:
> > > 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?
> 
> I agree; be faithful to the document's scope and just say LKR ->po LKW.
> 
> Were there other things like this in the table?  I didn't notice any.

None that I can think of, the others look good to me.

I'll do this change for v3.  Thank you for the suggestion.

  Andrea