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Date:   Sat, 3 Dec 2022 12:40:32 -0800
From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     Boqun Feng <boqun.feng@gmail.com>
Cc:     Jonas Oberhauser <jonas.oberhauser@huawei.com>,
        Jonas Oberhauser <jonas.oberhauser@huaweicloud.com>,
        "stern@rowland.harvard.edu" <stern@rowland.harvard.edu>,
        "parri.andrea@gmail.com" <parri.andrea@gmail.com>,
        "will@kernel.org" <will@kernel.org>,
        "peterz@infradead.org" <peterz@infradead.org>,
        "npiggin@gmail.com" <npiggin@gmail.com>,
        "dhowells@redhat.com" <dhowells@redhat.com>,
        "j.alglave@ucl.ac.uk" <j.alglave@ucl.ac.uk>,
        "luc.maranget@inria.fr" <luc.maranget@inria.fr>,
        "akiyks@gmail.com" <akiyks@gmail.com>,
        "dlustig@nvidia.com" <dlustig@nvidia.com>,
        "joel@joelfernandes.org" <joel@joelfernandes.org>,
        "urezki@gmail.com" <urezki@gmail.com>,
        "quic_neeraju@quicinc.com" <quic_neeraju@quicinc.com>,
        "frederic@kernel.org" <frederic@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] tools: memory-model: Make plain accesses carry
 dependencies
Message-ID: <20221203204032.GV4001@paulmck-ThinkPad-P17-Gen-1>
Reply-To: paulmck@kernel.org
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On Sat, Dec 03, 2022 at 12:14:29PM -0800, Boqun Feng wrote:
> On Sat, Dec 03, 2022 at 11:02:26AM -0800, Paul E. McKenney wrote:
> > On Sat, Dec 03, 2022 at 11:58:36AM +0000, Jonas Oberhauser wrote:
> > > 
> > > 
> > > -----Original Message-----
> > > From: Boqun Feng [mailto:boqun.feng@gmail.com] 
> > > Sent: Friday, December 2, 2022 7:50 PM
> > > 
> > > > > Reviewed-by: Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
> > > 
> > > > s/Reviewed-by: Reviewed-by:/Reviewed-by:^2 to save some space ? ;-)
> > > 
> > > 
> > > Oh, I didn't know I'm allowed to compress things like that! Can I use ? as well to save another character?
> > 
> > Heh!  I might miss that, and who knows?  The bots might think that "?"
> > was the first letter of your name.  ;-)
> > 
> > > > I wonder is this patch a first step to solve the OOTA problem you reported in OSS:
> > > >	https://static.sched.com/hosted_files/osseu2022/e1/oss-eu22-jonas.pdf
> > > > If so maybe it's better to put the link in the commit log I think.
> > > 
> > > It's not directly related to that specific problem, it does solve some other OOTA issues though.
> > > If you think we should link to the talk, there's also a video with slightly more updated slides from the actual talk: https://www.youtube.com/watch?v=iFDKhIxKhoQ
> > > do you think I should link to both then?
> > 
> > It is not hard for me to add that in if people believe that it should be
> > included.  But default is lazy in this case.  ;-)
> > 
> 
> I brought this up because, as we recently experience in RCU code, we
> need answers of "why we did this?" to the future us ;-)
> 
> I agree with Alan, this seems like a good idea, but having some big
> picture of why we do this may be better.

Fair enough!

How about something like this as a new paragraph at the end of
the commit log?

						Thanx, Paul

------------------------------------------------------------------------

For more on LKMM and dependencies, please see this Open Source Summit
talk:  https://www.youtube.com/watch?v=iFDKhIxKhoQ