From: "George Spelvin" <linux@horizon.com>
To: linux@horizon.com, rostedt@goodmis.org
Cc: linux-kernel@vger.kernel.org, paulmck@linux.vnet.ibm.com,
peterz@infradead.org, srivatsa.bhat@linux.vnet.ibm.com,
torvalds@linux-foundation.org
Subject: Re: [PATCH 0/6] Optimize the cpu hotplug locking -v2
Date: 11 Oct 2013 09:51:14 -0400 [thread overview]
Message-ID: <20131011135114.24362.qmail@science.horizon.com> (raw)
In-Reply-To: <20131011084507.1d691504@gandalf.local.home>
> The problem is that the scheduler doesn't see that the current task has
> preemption disabled. It only looks at the priorities of the current
> task, and if it can preempt it, it will. It sets the NEED_RESCHED to the
> current task and waits for the preemption to schedule it out.
Ah, got it. It's a priority inversion problem, and while there is a
standard solution (priority inheritance), if I were to suggest such a
heavyweight solution, Linus would start yelling again and Sarah would
get unhappy, and we all know how that ends up.
Thank you. I will now cease displaying my ignorance in public.
next prev parent reply other threads:[~2013-10-11 13:51 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-11 12:14 George Spelvin
2013-10-11 12:45 ` Steven Rostedt
2013-10-11 13:51 ` George Spelvin [this message]
-- strict thread matches above, loose matches on Subject: below --
2013-10-08 10:25 Peter Zijlstra
2013-10-08 15:27 ` Oleg Nesterov
2013-10-08 15:38 ` Peter Zijlstra
2013-10-10 5:50 ` Andrew Morton
2013-10-10 6:27 ` Ingo Molnar
2013-10-10 6:34 ` Andrew Morton
2013-10-10 7:27 ` Ingo Molnar
2013-10-10 7:33 ` Andrew Morton
2013-10-10 7:45 ` Ingo Molnar
2013-10-10 12:19 ` Peter Zijlstra
2013-10-10 14:57 ` Ingo Molnar
2013-10-10 15:21 ` Peter Zijlstra
2013-10-10 15:36 ` Oleg Nesterov
2013-10-10 16:50 ` Ingo Molnar
2013-10-10 17:13 ` Paul E. McKenney
2013-10-10 17:35 ` Ingo Molnar
2013-10-10 18:35 ` Peter Zijlstra
2013-10-10 15:26 ` Oleg Nesterov
2013-10-10 16:00 ` Andrew Morton
2013-10-10 16:36 ` Steven Rostedt
2013-10-10 16:43 ` Andrew Morton
2013-10-10 16:53 ` Peter Zijlstra
2013-10-10 17:13 ` Steven Rostedt
2013-10-10 17:48 ` Andrew Morton
2013-10-10 18:10 ` Linus Torvalds
2013-10-10 18:43 ` Steven Rostedt
2013-10-10 18:50 ` Peter Zijlstra
2013-10-10 19:15 ` Paul E. McKenney
2013-10-10 19:00 ` Linus Torvalds
2013-10-10 18:46 ` Peter Zijlstra
2013-10-10 18:34 ` Peter Zijlstra
2013-10-10 18:49 ` Linus Torvalds
2013-10-10 19:04 ` Steven Rostedt
2013-10-10 19:16 ` Linus Torvalds
2013-10-10 19:34 ` Peter Zijlstra
2013-10-10 19:34 ` Steven Rostedt
2013-10-11 6:09 ` Ingo Molnar
2013-10-11 12:38 ` Peter Zijlstra
2013-10-11 18:25 ` Oleg Nesterov
2013-10-11 20:48 ` Peter Zijlstra
2013-10-12 17:06 ` Oleg Nesterov
2013-10-14 9:05 ` Peter Zijlstra
2013-10-14 9:23 ` Paul E. McKenney
2013-10-15 1:01 ` Paul E. McKenney
2013-10-10 17:39 ` Oleg Nesterov
2013-10-10 16:52 ` Ingo Molnar
2013-10-10 17:44 ` Paul E. McKenney
2013-10-10 16:54 ` Oleg Nesterov
2013-10-10 19:04 ` Srivatsa S. Bhat
2013-10-10 18:52 ` Srivatsa S. Bhat
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