From: Ingo Molnar <mingo@elte.hu>
To: Ming Lei <tom.leiming@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
a.p.zijlstra@chello.nl, linux-kernel@vger.kernel.org,
akpm@linux-foundation.org
Subject: Re: [RESEND PATCH 0/11] kernel:lockdep:replace DFS with BFS
Date: Mon, 13 Jul 2009 09:02:48 +0200 [thread overview]
Message-ID: <20090713070248.GB28499@elte.hu> (raw)
In-Reply-To: <d82e647a0907111929u72ebe4b5t7cf638568e195adc@mail.gmail.com>
* Ming Lei <tom.leiming@gmail.com> wrote:
> > I don't have a strong opinion on this. I just don't think the
> > shortest path is the most important if there are many many
> > paths. Whatever AB-BA is encountered, all of them must be fixed.
> > What might give a degree of importance for such bad circle is
> > the window in which it triggers.
>
> The shortest path is just a characteristic of BFS, and we do not
> need to pay extra work for it. So finding the shortest circle
> have not any bad effect at least.
>
> IMHO, troubleshooting from the shortest circle is easier than from
> other circle.
Agreed. Making lockdep reports more readable (i.e. smaller) is a
very important goal.
Often the longer circles are just a side-effect of the shorter
circles and fixing the short one will fix the large ones too. So
printing the smallest is an advantage IMO.
Ingo
next prev parent reply other threads:[~2009-07-13 7:03 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-06-28 15:04 tom.leiming
2009-06-28 15:04 ` [RESEND PATCH 01/11] kernel:lockdep:print the shortest dependency chain if finding a circle tom.leiming
2009-06-28 15:04 ` [RESEND PATCH 02/11] kernel:lockdep:improve implementation of BFS tom.leiming
2009-06-28 15:04 ` [RESEND PATCH 03/11] kernel:lockdep: introduce match function to BFS tom.leiming
2009-06-28 15:04 ` [RESEND PATCH 04/11] kernel:lockdep:implement check_noncircular() by BFS tom.leiming
2009-06-28 15:04 ` [RESEND PATCH 05/11] kernel:lockdep:implement find_usage_*wards " tom.leiming
2009-06-28 15:04 ` [RESEND PATCH 06/11] kernel:lockdep:introduce print_shortest_lock_dependencies tom.leiming
2009-06-28 15:04 ` [RESEND PATCH 07/11] kernel:lockdep: implement lockdep_count_*ward_deps by BFS tom.leiming
2009-06-28 15:04 ` [RESEND PATCH 08/11] kernel:lockdep: update memory usage introduced " tom.leiming
2009-06-28 15:04 ` [RESEND PATCH 09/11] kernel:lockdep:add statistics info for max bfs queue depth tom.leiming
2009-06-28 15:04 ` [RESEND PATCH 10/11] BFS cleanup tom.leiming
2009-06-28 15:04 ` [RESEND PATCH 11/11] kernel:lockdep:fix return value of check_usage*() tom.leiming
2009-07-18 14:24 ` [tip:core/locking] lockdep: BFS cleanup tip-bot for Peter Zijlstra
2009-07-18 17:23 ` Peter Zijlstra
2009-08-02 13:03 ` tip-bot for Peter Zijlstra
2009-07-18 14:24 ` [tip:core/locking] lockdep: Add statistics info for max bfs queue depth tip-bot for Ming Lei
2009-08-02 13:03 ` tip-bot for Ming Lei
2009-07-18 14:24 ` [tip:core/locking] lockdep: Update memory usage introduced by BFS tip-bot for Ming Lei
2009-07-18 17:23 ` Peter Zijlstra
2009-08-02 13:02 ` tip-bot for Ming Lei
2009-07-18 14:24 ` [tip:core/locking] lockdep: Implement lockdep_count_*ward_deps " tip-bot for Ming Lei
2009-08-02 13:02 ` tip-bot for Ming Lei
2009-07-18 14:24 ` [tip:core/locking] lockdep: Introduce print_shortest_lock_dependencies tip-bot for Ming Lei
2009-08-02 13:02 ` tip-bot for Ming Lei
2009-07-18 14:23 ` [tip:core/locking] lockdep: Implement find_usage_*wards by BFS tip-bot for Ming Lei
2009-08-02 13:02 ` tip-bot for Ming Lei
2009-07-13 8:02 ` [RESEND PATCH 04/11] kernel:lockdep:implement check_noncircular() " Dave Young
2009-07-13 8:08 ` Dave Young
2009-07-21 3:33 ` Ming Lei
2009-07-18 14:23 ` [tip:core/locking] lockdep: Implement " tip-bot for Ming Lei
2009-08-02 13:02 ` tip-bot for Ming Lei
2009-07-18 14:23 ` [tip:core/locking] lockdep: Introduce match function to BFS tip-bot for Ming Lei
2009-08-02 13:01 ` tip-bot for Ming Lei
2009-07-18 14:23 ` [tip:core/locking] lockdep: Improve implementation of BFS tip-bot for Ming Lei
2009-08-02 13:01 ` tip-bot for Ming Lei
2009-07-11 21:30 ` [RESEND PATCH 01/11] kernel:lockdep:print the shortest dependency chain if finding a circle Frederic Weisbecker
2009-07-12 2:42 ` Ming Lei
2009-07-13 7:01 ` Ingo Molnar
2009-07-13 9:14 ` Peter Zijlstra
2009-07-13 13:56 ` Ming Lei
2009-07-13 13:51 ` Ming Lei
2009-07-13 9:01 ` Dave Young
2009-07-18 14:23 ` [tip:core/locking] lockdep: Print " tip-bot for Ming Lei
2009-08-02 13:01 ` tip-bot for Ming Lei
2009-07-11 0:43 ` [RESEND PATCH 0/11] kernel:lockdep:replace DFS with BFS Frederic Weisbecker
2009-07-11 3:25 ` Ming Lei
2009-07-11 21:09 ` Frederic Weisbecker
2009-07-12 2:29 ` Ming Lei
2009-07-13 7:02 ` Ingo Molnar [this message]
2009-07-13 9:16 ` Peter Zijlstra
2009-07-16 4:39 ` Ming Lei
2009-07-16 5:22 ` Peter Zijlstra
2009-07-16 7:12 ` Ming Lei
2009-07-16 9:54 ` Peter Zijlstra
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