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Date:   Tue, 3 Apr 2018 08:03:56 -0700
From:   "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     David Howells <dhowells@redhat.com>,
        Andrea Parri <andrea.parri@amarulasolutions.com>,
        Ingo Molnar <mingo@redhat.com>, linux-kernel@vger.kernel.org,
        Andrea Parri <parri.andrea@gmail.com>,
        Alan Stern <stern@rowland.harvard.edu>,
        Will Deacon <will.deacon@arm.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        Nicholas Piggin <npiggin@gmail.com>,
        Jade Alglave <j.alglave@ucl.ac.uk>,
        Luc Maranget <luc.maranget@inria.fr>,
        Akira Yokosawa <akiyks@gmail.com>
Subject: Re: [PATCH v2 1/3] locking: Document the semantics of
 spin_is_locked()
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On Tue, Apr 03, 2018 at 04:43:00PM +0200, Peter Zijlstra wrote:
> On Tue, Apr 03, 2018 at 07:17:18AM -0700, Paul E. McKenney wrote:
> > Suggestions for a fix?  Clearly great care is required when using it
> > in things like WARN_ON()...
> 
> Yeah, don't use it there, use lockdep_assert_held().

Good point, -ETOOEARLY.  ;-)

> As I stated before in this thread, ideally we'd make *_is_locked() go
> away entirely.

After being reminded of the issues on UP systems, I now have much more
sympathy for that view...

							Thanx, Paul