From: Byungchul Park <byungchul.park@lge.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: mingo@kernel.org, tj@kernel.org, boqun.feng@gmail.com,
david@fromorbit.com, johannes@sipsolutions.net, oleg@redhat.com,
linux-kernel@vger.kernel.org, kernel-team@lge.com
Subject: Re: [PATCH 4/4] lockdep: Fix workqueue crossrelease annotation
Date: Thu, 31 Aug 2017 17:15:01 +0900 [thread overview]
Message-ID: <20170831081501.GJ3240@X58A-UD3R> (raw)
In-Reply-To: <20170831080442.5vdgoaijzmrc776x@hirez.programming.kicks-ass.net>
On Thu, Aug 31, 2017 at 10:04:42AM +0200, Peter Zijlstra wrote:
> On Wed, Aug 30, 2017 at 08:25:46PM +0900, Byungchul Park wrote:
>
> > For example - I'm giving you the same example repeatedly:
> >
> > context X context Y
> > --------- ---------
> > wait_for_completion(C)
> > acquire(A)
> > process_one_work()
> > acquire(B)
> > work->fn()
> > complete(C)
> >
> > Please check C->A and C->B.
>
> Is there a caller of procesS_one_work() that holds a lock?
It's not important. Ok, check the following, instead:
context X context Y
--------- ---------
wait_for_completion(C)
acquire(A)
release(A)
process_one_work()
acquire(B)
release(B)
work->fn()
complete(C)
We don't need to lose C->A and C->B dependencies unnecessarily.
next prev parent reply other threads:[~2017-08-31 8:15 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-23 11:58 [PATCH 0/4] workqueue and lockdep stuffs Peter Zijlstra
2017-08-23 11:58 ` [PATCH 1/4] workqueue: Use TASK_IDLE Peter Zijlstra
2017-08-23 13:31 ` Tejun Heo
2017-08-23 11:58 ` [PATCH 2/4] lockdep/selftests: Add mixed read-write ABBA tests Peter Zijlstra
2017-08-23 11:58 ` [PATCH 3/4] workqueue/lockdep: Fix flush_work() annotation Peter Zijlstra
2017-08-23 11:58 ` [PATCH 4/4] lockdep: Fix workqueue crossrelease annotation Peter Zijlstra
2017-08-24 2:18 ` Byungchul Park
2017-08-24 14:02 ` Peter Zijlstra
2017-08-25 1:11 ` Byungchul Park
2017-08-29 8:59 ` Peter Zijlstra
2017-08-29 14:23 ` [tip:locking/core] locking/lockdep: Untangle xhlock history save/restore from task independence tip-bot for Peter Zijlstra
2017-08-29 16:02 ` [PATCH 4/4] lockdep: Fix workqueue crossrelease annotation Byungchul Park
2017-08-29 18:47 ` Peter Zijlstra
2017-08-30 2:09 ` Byungchul Park
2017-08-30 7:41 ` Byungchul Park
2017-08-30 8:53 ` Peter Zijlstra
2017-08-30 9:01 ` Byungchul Park
2017-08-30 9:12 ` Peter Zijlstra
2017-08-30 9:14 ` Peter Zijlstra
2017-08-30 9:35 ` Byungchul Park
2017-08-30 9:24 ` Byungchul Park
2017-08-30 11:25 ` Byungchul Park
2017-08-30 12:49 ` Byungchul Park
2017-08-31 7:26 ` Byungchul Park
2017-08-31 8:04 ` Peter Zijlstra
2017-08-31 8:15 ` Byungchul Park [this message]
2017-08-31 8:34 ` Peter Zijlstra
2017-09-01 2:05 ` Byungchul Park
2017-09-01 9:47 ` Peter Zijlstra
2017-09-01 10:16 ` Byungchul Park
2017-09-01 12:09 ` 박병철/선임연구원/SW Platform(연)AOT팀(byungchul.park@lge.com)
2017-09-01 12:38 ` Peter Zijlstra
2017-09-01 13:51 ` Byungchul Park
2017-09-01 16:38 ` Peter Zijlstra
2017-09-04 1:30 ` Byungchul Park
2017-09-04 2:08 ` Byungchul Park
2017-09-04 11:42 ` Peter Zijlstra
2017-09-05 0:38 ` Byungchul Park
2017-09-05 7:08 ` Peter Zijlstra
2017-09-05 7:19 ` Peter Zijlstra
2017-09-05 8:57 ` Byungchul Park
2017-09-05 9:36 ` Peter Zijlstra
2017-09-05 10:31 ` Byungchul Park
2017-09-05 10:52 ` Peter Zijlstra
2017-09-05 11:24 ` Byungchul Park
2017-09-05 10:58 ` Byungchul Park
2017-09-05 13:46 ` Peter Zijlstra
2017-09-05 23:52 ` Byungchul Park
2017-09-06 0:42 ` Boqun Feng
2017-09-06 1:32 ` Byungchul Park
2017-09-06 23:59 ` Byungchul Park
2017-09-07 0:11 ` Byungchul Park
2017-09-06 0:48 ` Byungchul Park
2017-09-05 8:30 ` Byungchul Park
2017-08-31 8:07 ` Peter Zijlstra
2017-08-25 4:39 ` Byungchul Park
2017-08-29 6:46 ` Byungchul Park
2017-08-29 9:01 ` Peter Zijlstra
2017-08-29 16:12 ` Byungchul Park
2017-08-23 13:32 ` [PATCH 0/4] workqueue and lockdep stuffs Tejun Heo
2017-08-23 13:45 ` Peter Zijlstra
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