Date: Mon, 11 Mar 2013 22:24:06 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Chuansheng Liu <chuansheng.liu@intel.com>
cc: mingo@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/3] genirq: Do not consider the irqs with disabling and
 IRQF_NO_SUSPEND
In-Reply-To: <1363024631.31506.64.camel@cliu38-desktop-build>
Message-ID: <alpine.LFD.2.02.1303112217180.22263@ionos>
References: <1363024396.31506.60.camel@cliu38-desktop-build> <1363024631.31506.64.camel@cliu38-desktop-build>
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On Tue, 12 Mar 2013, Chuansheng Liu wrote:
> According to commit 9c6079aa1bf(genirq: Do not consider disabled
> wakeup irqs), we should not break the suspend when one irq is pending
> but has been disabled before suspending.
> 
> But there is another case missed, that one irq with flag IRQF_NO_SUSPEND,
> which has been disabled before suspending, and irq pending there,
> in this case, we still should not break the suspending, otherwise,
> the suspend abort over and over.
> 
> Here also checking if the desc->istate & IRQS_SUSPENDED is true.

So what you are saying is:

If an interrupt which is marked IRQF_NO_SUSPEND has been disabled
before suspend invocation then desc->depth is 1 and therefor it should
not be checked for IRQS_PENDING in check_wakeup_irqs().

Makes sense, though the changelog needs to be more clear and the code
wants to have a proper comment.

Thanks,

	tglx
 
> Signed-off-by: liu chuansheng <chuansheng.liu@intel.com>
> ---
>  kernel/irq/pm.c |    3 ++-
>  1 files changed, 2 insertions(+), 1 deletions(-)
> 
> diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c
> index cb228bf..1470c1b 100644
> --- a/kernel/irq/pm.c
> +++ b/kernel/irq/pm.c
> @@ -109,7 +109,8 @@ int check_wakeup_irqs(void)
>  		 * can abort suspend.
>  		 */
>  		if (irqd_is_wakeup_set(&desc->irq_data)) {
> -			if (desc->depth == 1 && desc->istate & IRQS_PENDING)
> +			if (desc->depth == 1 && (desc->istate & IRQS_PENDING)
> +				&& (desc->istate & IRQS_SUSPENDED))
>  				return -EBUSY;
>  			continue;
>  		}
> -- 
> 1.7.0.4
> 
> 
> 
> 
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