From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>,
David Miller <davem@davemloft.net>,
hugh@veritas.com, mingo@elte.hu, akpm@linux-foundation.org,
linux-kernel@vger.kernel.org, davej@redhat.com
Subject: Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock()
Date: Mon, 04 Aug 2008 21:39:02 +0200 [thread overview]
Message-ID: <1217878742.3589.70.camel@twins> (raw)
In-Reply-To: <alpine.LFD.1.10.0808041230070.3340@nehalem.linux-foundation.org>
On Mon, 2008-08-04 at 12:31 -0700, Linus Torvalds wrote:
>
> On Mon, 4 Aug 2008, Jeremy Fitzhardinge wrote:
> >
> > OK. I don't actually need to do this, but I was asking for completeness. But
> > to clarify, you only need to do the reverse unlock if you do it after
> > unlocking the outer lock? If you're still holding the outer lock, you can
> > unlock in any order?
>
> Release order should always be totally irrelevant, whether you hold outer
> locks or not. Only the order of _getting_ locks matter.
>
> And yes, if there is an outer lock, even the order of getting locks is
> irrelevant, as long as anybody who gets more than one inner lock always
> holds the outer one.
I agree, its just non-trivial to convince lockdep of this. I can give it
a go though.
next prev parent reply other threads:[~2008-08-04 19:39 UTC|newest]
Thread overview: 73+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-08-04 13:03 [RFC][PATCH 0/7] lockdep Peter Zijlstra
2008-08-04 13:03 ` [RFC][PATCH 1/7] lockdep: Fix combinatorial explosion in lock subgraph traversal Peter Zijlstra
2008-08-05 8:34 ` David Miller
2008-08-05 8:46 ` Peter Zijlstra
2008-08-13 3:48 ` Tim Pepper
2008-08-13 10:56 ` Ingo Molnar
2008-08-04 13:03 ` [RFC][PATCH 2/7] lockdep: lock_set_subclass - reset a held locks subclass Peter Zijlstra
2008-08-05 8:35 ` David Miller
2008-08-04 13:03 ` [RFC][PATCH 3/7] lockdep: re-annotate scheduler runqueues Peter Zijlstra
2008-08-05 8:35 ` David Miller
2008-08-04 13:03 ` [RFC][PATCH 4/7] lockdep: shrink held_lock structure Peter Zijlstra
2008-08-05 16:08 ` Peter Zijlstra
2008-08-06 7:17 ` Peter Zijlstra
2008-08-04 13:03 ` [RFC][PATCH 5/7] lockdep: map_acquire Peter Zijlstra
2008-08-04 13:03 ` [RFC][PATCH 6/7] lockdep: lock protection locks Peter Zijlstra
2008-08-04 13:03 ` [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock() Peter Zijlstra
2008-08-04 14:07 ` Roland Dreier
2008-08-04 14:19 ` Peter Zijlstra
2008-08-04 14:26 ` Roland Dreier
2008-08-04 14:32 ` Peter Zijlstra
2008-08-04 14:53 ` Dave Jones
2008-08-04 14:56 ` Peter Zijlstra
2008-08-04 16:26 ` Andrea Arcangeli
2008-08-04 16:38 ` Peter Zijlstra
2008-08-04 17:27 ` Andrea Arcangeli
2008-08-04 17:46 ` Andrea Arcangeli
2008-08-04 17:57 ` [PATCH] workaround minor lockdep bug triggered by mm_take_all_locks Andrea Arcangeli
2008-08-04 18:48 ` Peter Zijlstra
2008-08-04 18:56 ` Roland Dreier
2008-08-04 19:05 ` Peter Zijlstra
2008-08-04 20:15 ` Andrea Arcangeli
2008-08-04 20:37 ` Peter Zijlstra
2008-08-04 21:09 ` Andrea Arcangeli
2008-08-04 21:14 ` Pekka Enberg
2008-08-04 21:30 ` Andrea Arcangeli
2008-08-04 21:41 ` Andrew Morton
2008-08-04 22:12 ` Andrea Arcangeli
2008-08-04 21:42 ` Arjan van de Ven
2008-08-04 22:30 ` Andrea Arcangeli
2008-08-04 23:38 ` Arjan van de Ven
2008-08-05 0:47 ` Andrea Arcangeli
2008-08-04 21:27 ` Arjan van de Ven
2008-08-04 21:54 ` Andrea Arcangeli
2008-08-04 21:57 ` David Miller
2008-08-05 2:00 ` Roland Dreier
2008-08-05 2:18 ` Andrea Arcangeli
2008-08-05 12:02 ` Roland Dreier
2008-08-05 12:20 ` Andrea Arcangeli
2008-08-04 18:48 ` [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock() Peter Zijlstra
2008-08-04 21:32 ` David Miller
2008-08-04 18:06 ` Jeremy Fitzhardinge
2008-08-04 18:54 ` Peter Zijlstra
2008-08-04 19:26 ` Jeremy Fitzhardinge
2008-08-04 19:31 ` Linus Torvalds
2008-08-04 19:39 ` Peter Zijlstra [this message]
2008-08-04 20:16 ` Jeremy Fitzhardinge
2008-10-08 15:27 ` Steven Rostedt
2008-10-08 15:43 ` Linus Torvalds
2008-10-08 16:03 ` Steven Rostedt
2008-10-08 16:19 ` Linus Torvalds
2008-10-08 16:53 ` Steven Rostedt
2008-10-08 15:52 ` Nick Piggin
2008-10-08 17:18 ` Steven Rostedt
2008-08-07 11:25 ` Peter Zijlstra
2008-08-07 11:25 ` [RFC][PATCH 8/7] lockdep: annotate mm_take_all_locks() Peter Zijlstra
2008-08-07 11:25 ` [RFC][PATCH 9/7] mm: fix mm_take_all_locks() locking order Peter Zijlstra
2008-08-07 12:14 ` Hugh Dickins
2008-08-07 12:41 ` Peter Zijlstra
2008-08-07 13:27 ` Hugh Dickins
2008-08-07 21:46 ` Andrea Arcangeli
2008-08-08 1:34 ` Andrea Arcangeli
2008-08-08 7:16 ` Peter Zijlstra
2008-08-11 10:08 ` [RFC][PATCH 0/7] lockdep Ingo Molnar
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1217878742.3589.70.camel@twins \
--to=a.p.zijlstra@chello.nl \
--cc=akpm@linux-foundation.org \
--cc=davej@redhat.com \
--cc=davem@davemloft.net \
--cc=hugh@veritas.com \
--cc=jeremy@goop.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox