Re: [PATCH v2] tools: memory-model: Make plain accesses carry dependencies

From: Paul E. McKenney
Date: Sat Dec 03 2022 - 15:40:40 EST


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@xxxxxxxxx]
> > > Sent: Friday, December 2, 2022 7:50 PM
> > >
> > > > > Reviewed-by: Reviewed-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
> > >
> > > > 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 ² as well to save another character?
> >
> > Heh! I might miss that, and who knows? The bots might think that "²"
> > 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

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