From: Oleg Nesterov <oleg@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Byungchul Park <byungchul.park@lge.com>,
mingo@kernel.org, linux-kernel@vger.kernel.org,
kernel-team@lge.com, Arnaldo Carvalho de Melo <acme@kernel.org>,
Dave Chinner <david@fromorbit.com>, Tejun Heo <tj@kernel.org>,
johannes@sipsolutions.net
Subject: Re: [PATCH v3 1/3] lockdep: Make LOCKDEP_CROSSRELEASE configs all part of PROVE_LOCKING
Date: Wed, 23 Aug 2017 18:39:03 +0200 [thread overview]
Message-ID: <20170823163903.GA12973@redhat.com> (raw)
In-Reply-To: <20170822144602.uh5jzkkchvdgzs3s@hirez.programming.kicks-ass.net>
Peter, I am all confused and I am still trying to understand your email.
In particular, because I no longer understand the lockdep annotations in
workqueue.c, it turns out I forgot everything...
On 08/22, Peter Zijlstra wrote:
>
> I am however slightly puzzled by the need of flush_work() to take Q,
> what deadlock potential is there?
Do you really mean flush_work()? Or start_flush_work() ?
> It was added by Oleg in commit:
>
> a67da70dc095 ("workqueues: lockdep annotations for flush_work()")
No, these annotations were moved later into start_flush, iiuc...
This
lock_map_acquire(&work->lockdep_map);
lock_map_release(&work->lockdep_map);
was added by another commit 0976dfc1d0cd80a4e9dfaf87bd8744612bde475a
"workqueue: Catch more locking problems with flush_work()", and at
first glance it is fine.
At the same time, I have a vague feeling that (perhaps) we can remove
these 2 annotations if we change process_one_work() and start_flush_work(),
not sure...
Oleg.
next prev parent reply other threads:[~2017-08-23 16:39 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-17 8:57 [PATCH v3 1/3] lockdep: Make LOCKDEP_CROSSRELEASE configs all part of PROVE_LOCKING Byungchul Park
2017-08-17 8:57 ` [PATCH v3 2/3] lockdep: Reword title of LOCKDEP_CROSSRELEASE config Byungchul Park
2017-08-17 10:21 ` [tip:locking/core] locking/lockdep: " tip-bot for Byungchul Park
2017-08-17 8:57 ` [PATCH v3 3/3] lockdep: Rename LOCKDEP_COMPLETE config Byungchul Park
2017-08-17 10:22 ` [tip:locking/core] locking/lockdep: Rename CONFIG_LOCKDEP_COMPLETE to CONFIG_LOCKDEP_COMPLETIONS tip-bot for Byungchul Park
2017-08-17 10:21 ` [tip:locking/core] locking/lockdep: Make CONFIG_LOCKDEP_CROSSRELEASE part of CONFIG_PROVE_LOCKING tip-bot for Byungchul Park
2017-08-17 10:45 ` Ingo Molnar
2017-08-18 5:33 ` Byungchul Park
2017-08-21 15:46 ` [PATCH v3 1/3] lockdep: Make LOCKDEP_CROSSRELEASE configs all part of PROVE_LOCKING Peter Zijlstra
2017-08-22 5:14 ` Byungchul Park
2017-08-22 7:52 ` Peter Zijlstra
2017-08-22 8:51 ` Byungchul Park
2017-08-22 9:21 ` Peter Zijlstra
2017-08-22 9:33 ` Byungchul Park
2017-08-22 10:08 ` Peter Zijlstra
2017-08-22 13:49 ` Peter Zijlstra
2017-08-22 14:46 ` Peter Zijlstra
2017-08-22 15:10 ` Peter Zijlstra
2017-08-22 15:59 ` Oleg Nesterov
2017-08-22 16:35 ` Peter Zijlstra
2017-08-23 16:39 ` Oleg Nesterov [this message]
2017-08-23 17:47 ` Peter Zijlstra
2017-08-24 6:11 ` Byungchul Park
2017-08-24 7:37 ` Byungchul Park
2017-08-24 8:11 ` Byungchul Park
2017-08-25 1:14 ` Byungchul Park
2017-08-29 15:52 ` Oleg Nesterov
2017-08-29 17:07 ` lockdep && recursive-read Oleg Nesterov
2017-08-29 17:30 ` Peter Zijlstra
2017-08-29 17:51 ` [PATCH v3 1/3] lockdep: Make LOCKDEP_CROSSRELEASE configs all part of PROVE_LOCKING Peter Zijlstra
2017-08-23 2:43 ` Byungchul Park
2017-08-23 6:31 ` Byungchul Park
2017-08-23 10:26 ` Peter Zijlstra
2017-08-24 5:07 ` Byungchul Park
2017-08-22 5:46 ` Dave Chinner
2017-08-22 9:06 ` Peter Zijlstra
2017-08-22 9:22 ` Byungchul Park
2017-08-22 9:37 ` Peter Zijlstra
2017-08-22 9:42 ` Peter Zijlstra
2017-08-23 2:12 ` Byungchul Park
2017-08-23 6:03 ` Byungchul Park
2017-08-23 10:20 ` Peter Zijlstra
2017-08-24 2:02 ` Byungchul Park
2017-08-24 7:30 ` Byungchul Park
2017-08-22 21:19 ` Dave Chinner
2017-08-23 2:31 ` Byungchul Park
2017-08-23 6:11 ` Byungchul Park
2017-08-23 10:46 ` Peter Zijlstra
2017-08-24 5:06 ` Byungchul Park
2017-08-23 1:56 ` Byungchul Park
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