From: Tejun Heo <tj@kernel.org>
To: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Peter Zijlstra <peterz@infradead.org>,
linux-kernel@vger.kernel.org, torvalds@linux-foundation.org,
tglx@linutronix.de, linux-pm@vger.kernel.org
Subject: Re: [PATCHSET] workqueue: reimplement CPU hotplug to keep idle workers
Date: Fri, 20 Jul 2012 12:41:14 -0700 [thread overview]
Message-ID: <20120720194114.GA21218@google.com> (raw)
In-Reply-To: <201207202144.05154.rjw@sisk.pl>
Hello, Rafael.
On Fri, Jul 20, 2012 at 09:44:04PM +0200, Rafael J. Wysocki wrote:
> Well, there are use cases I'm not really familiar with.
>
> Pretty much the only use case I'm sufficiently familiar with is
> suspend/hibernate where we unplug all of the nonboot CPUs at one point.
>
> The other use cases, which I don't really think are entirely valid,
> are on some ARM platforms where CPUs are unplugged instead of being put into
> C-states or equivalent (because we don't have a good mechanism for handling
> multiprocessor C-states; there's a set of patches for that waiting for
> the merge window in the Len's tree). I'm hoping to get rid of those
> use cases in future entirely.
I see, so the highest frequency user would most likely be
suspend/resume - especially with opportunistic approach like the one
used in androids.
Thanks for the explanation.
--
tejun
next prev parent reply other threads:[~2012-07-20 19:41 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-17 17:12 [PATCHSET] workqueue: reimplement CPU hotplug to keep idle workers Tejun Heo
2012-07-17 17:12 ` [PATCH 1/9] workqueue: perform cpu down operations from low priority cpu_notifier() Tejun Heo
2012-07-20 21:52 ` Paul E. McKenney
2012-07-20 21:58 ` Tejun Heo
2012-07-21 21:36 ` Paul E. McKenney
2012-07-22 16:43 ` [PATCH] workqueue: fix spurious CPU locality WARN from process_one_work() Tejun Heo
2012-07-22 21:23 ` Paul E. McKenney
2012-07-17 17:12 ` [PATCH 2/9] workqueue: drop CPU_DYING notifier operation Tejun Heo
2012-07-17 17:12 ` [PATCH 3/9] workqueue: ROGUE workers are UNBOUND workers Tejun Heo
2012-07-17 17:12 ` [PATCH 4/9] workqueue: use mutex for global_cwq manager exclusion Tejun Heo
2012-07-17 17:12 ` [PATCH 5/9] workqueue: drop @bind from create_worker() Tejun Heo
2012-07-17 17:12 ` [PATCH 6/9] workqueue: reimplement CPU online rebinding to handle idle workers Tejun Heo
2012-07-17 17:12 ` [PATCH 7/9] workqueue: don't butcher idle workers on an offline CPU Tejun Heo
2012-07-17 17:12 ` [PATCH 8/9] workqueue: remove CPU offline trustee Tejun Heo
2012-07-17 17:12 ` [PATCH 9/9] workqueue: simplify CPU hotplug code Tejun Heo
2012-07-17 18:43 ` [PATCHSET] workqueue: reimplement CPU hotplug to keep idle workers Rafael J. Wysocki
2012-07-17 19:40 ` Tejun Heo
2012-07-20 15:48 ` Peter Zijlstra
2012-07-20 17:02 ` Tejun Heo
2012-07-20 17:21 ` Peter Zijlstra
2012-07-20 17:50 ` Tejun Heo
2012-07-20 18:22 ` Peter Zijlstra
2012-07-20 18:34 ` Tejun Heo
2012-07-20 19:44 ` Rafael J. Wysocki
2012-07-20 19:41 ` Tejun Heo [this message]
2012-07-21 6:42 ` Shilimkar, Santosh
2012-07-23 8:38 ` Peter De Schrijver
2012-07-20 16:39 ` Peter Zijlstra
2012-07-20 16:52 ` Tejun Heo
2012-07-20 17:01 ` Peter Zijlstra
2012-07-20 17:08 ` Tejun Heo
2012-07-20 17:19 ` Peter Zijlstra
2012-07-20 17:43 ` Tejun Heo
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