Re: [PATCH v2] rtmutex: take the waiter lock with irqs off

From: Frederic Weisbecker
Date: Mon Nov 18 2013 - 19:00:09 EST


On Mon, Nov 18, 2013 at 03:10:21PM +0100, Peter Zijlstra wrote:
> --- a/kernel/softirq.c
> +++ b/kernel/softirq.c
> @@ -746,13 +746,23 @@ void irq_exit(void)
> #endif
>
> account_irq_exit_time(current);
> - trace_hardirq_exit();
> sub_preempt_count(HARDIRQ_OFFSET);
> - if (!in_interrupt() && local_softirq_pending())
> + if (!in_interrupt() && local_softirq_pending()) {
> + /*
> + * Temp. disable hardirq context so as not to confuse lockdep;
> + * otherwise it might think we're running softirq handler from
> + * hardirq context.
> + *
> + * Should probably sort this someplace else..
> + */
> + trace_hardirq_exit();
> invoke_softirq();
> + trace_hardirq_enter();
> + }
>
> tick_irq_exit();
> rcu_irq_exit();
> + trace_hardirq_exit();

Looks like a change we really want!

Thanks!

> }
>
> void raise_softirq(unsigned int nr)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/