lkml.org 
[lkml]   [2013]   [Feb]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 2/3] stop_machine: dequeue work before signal completion
On Wed, Feb 06, 2013 at 08:38:43PM +0800, Hillf Danton wrote:
> As handled by the kernel thread, work is dequeued first for further actions.

Ditto as the previous patch.

> Signed-off-by: Hillf Danton <dhillf@gmail.com>
> ---
>
> --- a/kernel/stop_machine.c Wed Feb 6 19:57:12 2013
> +++ b/kernel/stop_machine.c Wed Feb 6 20:02:12 2013
> @@ -334,23 +334,24 @@ static int __cpuinit cpu_stop_cpu_callba
> #ifdef CONFIG_HOTPLUG_CPU
> case CPU_UP_CANCELED:
> case CPU_POST_DEAD:
> - {
> - struct cpu_stop_work *work;
> -
> sched_set_stop_task(cpu, NULL);
> /* kill the stopper */
> kthread_stop(stopper->thread);
> /* drain remaining works */
> spin_lock_irq(&stopper->lock);
> - list_for_each_entry(work, &stopper->works, list)
> + while (!list_empty(&stopper->works)) {
> + struct cpu_stop_work *work;
> + work = list_first_entry(&stopper->works,
> + struct cpu_stop_work, list);
> + list_del_init(&work->list);
> cpu_stop_signal_done(work->done, false, 0);
> + }
> stopper->enabled = false;
> spin_unlock_irq(&stopper->lock);

Why does this matter? It's inside spinlock. What's being made better
by this change?

--
tejun


\
 
 \ /
  Last update: 2013-02-06 20:22    [W:0.088 / U:1.084 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site