From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: frank.rowand@am.sony.com
Cc: Chris Mason <chris.mason@oracle.com>,
"Rowand, Frank" <Frank_Rowand@sonyusa.com>,
Ingo Molnar <mingo@elte.hu>, Thomas Gleixner <tglx@linutronix.de>,
Mike Galbraith <efault@gmx.de>, Oleg Nesterov <oleg@redhat.com>,
Paul Turner <pjt@google.com>, Jens Axboe <axboe@kernel.dk>,
Yong Zhang <yong.zhang0@gmail.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 20/22] sched: Move the second half of ttwu() to the remote cpu
Date: Wed, 16 Mar 2011 09:32:20 +0100 [thread overview]
Message-ID: <1300264340.2250.75.camel@laptop> (raw)
In-Reply-To: <4D797E92.20408@am.sony.com>
On Thu, 2011-03-10 at 17:44 -0800, Frank Rowand wrote:
> > @@ -6287,6 +6342,7 @@ migration_call(struct notifier_block *nf
> >
> > #ifdef CONFIG_HOTPLUG_CPU
> > case CPU_DYING:
>
> Should pi_lock be locked here, so that additional wake ups can not
> be put on the wake list in the window after sched_ttwu_pending()
> completes, and before set_rq_offline(rq) is called? If so, then
> of course unlock pi_lock after the matching
> "raw_spin_unlock_irqrestore(&rq->lock, flags);"
The cpu should be offline already, so select_task_rq() will never return
it and hence no new tasks should end up on this list.
> > + sched_ttwu_pending();
> > /* Update our root-domain */
next prev parent reply other threads:[~2011-03-16 8:30 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-02 17:38 [PATCH 00/22] sched: Reduce runqueue lock contention -v5 Peter Zijlstra
2011-03-02 17:38 ` [PATCH 01/22] sched: Provide scheduler_ipi() callback in response to smp_send_reschedule() Peter Zijlstra
2011-03-11 1:36 ` Frank Rowand
2011-03-16 8:30 ` Peter Zijlstra
2011-03-11 15:07 ` [01/22] " Milton Miller
2011-03-11 15:27 ` Peter Zijlstra
2011-03-15 3:59 ` Milton Miller
2011-03-15 9:13 ` Peter Zijlstra
2011-03-02 17:38 ` [PATCH 02/22] sched: Always provide p->on_cpu Peter Zijlstra
2011-03-02 17:38 ` [PATCH 03/22] mutex: Use p->on_cpu for the adaptive spin Peter Zijlstra
2011-03-02 17:38 ` [PATCH 04/22] sched: Change the ttwu success details Peter Zijlstra
2011-03-02 17:38 ` [PATCH 05/22] sched: Clean up ttwu stats Peter Zijlstra
2011-03-02 17:38 ` [PATCH 06/22] sched: Provide p->on_rq Peter Zijlstra
2011-03-02 17:38 ` [PATCH 07/22] sched: Serialize p->cpus_allowed and ttwu() using p->pi_lock Peter Zijlstra
2011-03-02 17:38 ` [PATCH 08/22] sched: Drop the rq argument to sched_class::select_task_rq() Peter Zijlstra
2011-03-02 17:38 ` [PATCH 09/22] sched: Remove rq argument to sched_class::task_waking() Peter Zijlstra
2011-03-02 17:38 ` [PATCH 10/22] sched: Deal with non-atomic min_vruntime reads on 32bits Peter Zijlstra
2011-03-02 17:38 ` [PATCH 11/22] sched: Delay task_contributes_to_load() Peter Zijlstra
2011-03-02 17:38 ` [PATCH 12/22] sched: Also serialize ttwu_local() with p->pi_lock Peter Zijlstra
2011-03-02 17:38 ` [PATCH 13/22] sched: Add p->pi_lock to task_rq_lock() Peter Zijlstra
2011-03-02 17:38 ` [PATCH 14/22] sched: Drop rq->lock from first part of wake_up_new_task() Peter Zijlstra
2011-03-02 17:38 ` [PATCH 15/22] sched: Drop rq->lock from sched_exec() Peter Zijlstra
2011-03-02 17:38 ` [PATCH 16/22] sched: Remove rq->lock from the first half of ttwu() Peter Zijlstra
2011-03-02 17:38 ` [PATCH 17/22] sched: Remove rq argument from ttwu_stat() Peter Zijlstra
2011-03-02 17:38 ` [PATCH 18/22] sched: Rename ttwu_post_activation Peter Zijlstra
2011-03-02 17:38 ` [PATCH 19/22] sched: Restructure ttwu some more Peter Zijlstra
2011-03-02 17:38 ` [PATCH 20/22] sched: Move the second half of ttwu() to the remote cpu Peter Zijlstra
2011-03-11 1:44 ` Frank Rowand
2011-03-16 8:32 ` Peter Zijlstra [this message]
2011-03-02 17:38 ` [PATCH 21/22] sched: Remove need_migrate_task() Peter Zijlstra
2011-03-02 17:38 ` [PATCH 22/22] sched: Remove TASK_WAKING Peter Zijlstra
2011-03-11 1:49 ` Frank Rowand
2011-03-16 9:53 ` Peter Zijlstra
2011-03-11 1:51 ` [PATCH 00/22] sched: Reduce runqueue lock contention -v5 Frank Rowand
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