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From: Thomas Gleixner <tglx@linutronix.de>
To: Angus Chen <angus.chen@jaguarmicro.com>
Cc: linux-kernel@vger.kernel.org, Angus Chen <angus.chen@jaguarmicro.com>
Subject: Re: [PATCH] genirq: Fix irqs_unhandled in note_interrupt
In-Reply-To: <20231128021043.2099-1-angus.chen@jaguarmicro.com>
References: <20231128021043.2099-1-angus.chen@jaguarmicro.com>
Date: Mon, 19 Feb 2024 16:03:46 +0100
Message-ID: <874je4a431.ffs@tglx>
Precedence: bulk
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On Tue, Nov 28 2023 at 10:10, Angus Chen wrote:
> Commit 4f27c00bf80f ("Improve behaviour of spurious IRQ detect")
> introduced a age of last_unhandled,after irq_count reached 100000,
> we set irqs_unhandled = 0,but we didn't clear last_unhandled.

We do nothing. Please write changelogs in passive voice.

> So we can see the print of irq_spurious_proc_show is not consistent.
> Like below:
> root@jmkernel:~# cat /proc/irq/138/spurious
> count 99998
> unhandled 1
> last_unhandled 1543930240 ms
>
> root@jmkernel:~# cat /proc/irq/138/spurious
> count 0
> unhandled 0
> last_unhandled 1548915240 ms

I can't figure out what you are trying to demonstrate here.

> we can set last_unhandled=1 as a prompting message.

This makes no sense either.

> Signed-off-by: Angus Chen <angus.chen@jaguarmicro.com>
> ---
>  kernel/irq/spurious.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
> index 02b2daf07441..e883df04bdf1 100644
> --- a/kernel/irq/spurious.c
> +++ b/kernel/irq/spurious.c
> @@ -428,7 +428,7 @@ void note_interrupt(struct irq_desc *desc, irqreturn_t action_ret)
>  		mod_timer(&poll_spurious_irq_timer,
>  			  jiffies + POLL_SPURIOUS_IRQ_INTERVAL);
>  	}
> -	desc->irqs_unhandled = 0;
> +	desc->irqs_unhandled = 1;

Why? Just to do some incomprehensible /proc/ output cosmetics instead of
fixing the related procfs function?

Thanks,

        tglx