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Date:   Thu, 10 Jan 2019 09:40:24 +0100
From:   Andrea Parri <andrea.parri@amarulasolutions.com>
To:     "Paul E. McKenney" <paulmck@linux.ibm.com>
Cc:     linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
        mingo@kernel.org, stern@rowland.harvard.edu,
        parri.andrea@gmail.com, will.deacon@arm.com, peterz@infradead.org,
        boqun.feng@gmail.com, npiggin@gmail.com, dhowells@redhat.com,
        j.alglave@ucl.ac.uk, luc.maranget@inria.fr, akiyks@gmail.com,
        willy@infradead.org
Subject: Re: [PATCH RFC memory-model 0/6] LKMM updates
Message-ID: <20190110084024.GA10280@andrea>
References: <20190109210706.GA27268@linux.ibm.com>
 <20190109231852.GA4494@andrea>
 <20190109234043.GD1215@linux.ibm.com>
 <20190110003952.GA4354@andrea>
 <20190110042027.GG1215@linux.ibm.com>
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> > > > It seems that
> > > > 
> > > >   1b52d0186177 ("tools/memory-model: Model smp_mb__after_unlock_lock()")
> > > >   
> > > > from linux-rcu/dev got lost; this also needs an ack (probably yours! ;D,
> > > > considered that, IIRC, you introduced the primitive and RCU is currently
> > > > its only user.)
> > > 
> > > That commit is in -tip:
> > > 
> > > 4607abbcf464 ("tools/memory-model: Model smp_mb__after_unlock_lock()")
> > > 
> > > So it has already left my -rcu tree.  ;-)
> > 
> > Oh, you're right: now I see the commit (e.g., with "git show"), but I
> > don't see the corresponding changes applied to the tree.
> > 
> >   https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?h=locking/core&id=4607abbcf464ea2be14da444215d05c73025cf6e
> >   https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/tree/tools/memory-model/linux-kernel.bell?h=locking/core
> > 
> > Is this expected?
> 
> Are you asking why it is in -tip but not in mainline?  I am not sure,
> but given that the merge window was over the holiday season and that
> the length of the merge window proved to be shorter than many people
> expected it to be, I am not too surprised.  ;-)

Mmh, let me try again:

  $ git clone git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git
  $ cd tip
  $ git checkout -b locking/core origin/locking/core

  $ git show 4607abbcf464
  commit 4607abbcf464ea2be14da444215d05c73025cf6e
  Author: Andrea Parri <andrea.parri@amarulasolutions.com>
  Date:   Mon Dec 3 15:04:49 2018 -0800

      tools/memory-model: Model smp_mb__after_unlock_lock()

  $ cd tools/memory-model
  $ herd7 -conf linux-kernel.cfg after-unlock-lock-same-cpu.litmus
  File "after-unlock-lock-same-cpu.litmus": Unknown macro smp_mb__after_unlock_lock (User error)

  [aka, linux-kernel.def in tip:locking/core does not have the
   smp_mb__after_unlock_lock() added by 4607abbcf464]

  Andrea


> 
> 							Thanx, Paul
>