From: Byungchul Park <byungchul.park@lge.com>
To: Boqun Feng <boqun.feng@gmail.com>, peterz@infradead.org
Cc: Peter Zijlstra <peterz@infradead.org>,
Byungchul Park <max.byungchul.park@gmail.com>,
Ingo Molnar <mingo@kernel.org>, Tejun Heo <tj@kernel.org>,
david@fromorbit.com, Johannes Berg <johannes@sipsolutions.net>,
oleg@redhat.com,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
kernel-team@lge.com
Subject: Re: [PATCH 4/4] lockdep: Fix workqueue crossrelease annotation
Date: Thu, 7 Sep 2017 09:11:55 +0900 [thread overview]
Message-ID: <20170907001155.GD3240@X58A-UD3R> (raw)
In-Reply-To: <20170906013254.GB3240@X58A-UD3R>
On Wed, Sep 06, 2017 at 10:32:54AM +0900, Byungchul Park wrote:
> > What do you mean by "false dependencies"? AFAICT, recursive-read could
>
> All locks used in every work->func() generate false dependencies with
> 'work' and 'wq', while any flush works are not involved. It's inevitable.
>
> Moreover, it's also possible to generate more false ones between the
> pseudo acquisitions, if real acquisitions are used for that speculative
> purpose e.i. recursive-read here, which are anyway real ones.
>
> Moreover, it's also possible to generate more false ones between holding
> locks and the pseudo ones, of course, the workqueue code is not the case
> for now.
>
> Moreover, it's also possible to generate more false ones between the
> pseudo ones and crosslocks on commit, once making crossrelease work even
> for recursive-read things.
Hi Peter,
What do you think about the above? Just let me know please. It's ok if
you think it's not needed yet.
Or, if you think it's necessary from now on, I'm going ahead for that
work, starting from renaming the 'might' thing.
next prev parent reply other threads:[~2017-09-07 0:12 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
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 [this message]
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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