Subject: Re: [PATCH] x86/apic: Remove the extra judgement of skipped IO APIC
 setup
To: Ingo Molnar <mingo@kernel.org>
References: <1487841401-1543-1-git-send-email-douly.fnst@cn.fujitsu.com>
 <20170301090455.GA23669@gmail.com>
CC: <tglx@linutronix.de>, <hpa@zytor.com>, <bp@alien8.de>,
        <wanpeng.li@hotmail.com>, <nicstange@gmail.com>, <x86@kernel.org>,
        <linux-kernel@vger.kernel.org>
From: Dou Liyang <douly.fnst@cn.fujitsu.com>
Message-ID: <20f40557-b9ca-7442-a9af-3beccb0093d9@cn.fujitsu.com>
Date: Wed, 1 Mar 2017 17:31:55 +0800
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Dear Ingo,

At 03/01/2017 05:04 PM, Ingo Molnar wrote:
[...]
>> +		pr_info("Not init interrupt remapping due to skipped IO-APIC setup\n");
>
> So you replaced a perfectly readable kernel message:
>
>  -		pr_info("Not enabling interrupt remapping due to skipped IO-APIC setup\n");
>
> ... with an unreadable one:
>
>  +		pr_info("Not init interrupt remapping due to skipped IO-APIC setup\n");
>
> Why?

I am very sorry.

Because of my weak English skills :) . I am trying to improve my
English ability.

>
> Also, the changelog is pretty much unreadable as well:
>
>> As the commit 2e63ad4bd5dd ("x86/apic: Do not init irq remapping
>> if ioapic is disabled") added the judgement of skipped IO APIC
>> setup at the beginning of enable_IR_x2apic(). It may be redundant
>> that we check it again when we try to enable the interrupt mapping.
>>
>> So, remove the one in try_to_enable_IR() and refine them for
>> better readability.
>
> I edited it to:

Thanks very much ! it became very clear.

>
>    The following commit:
>
>      2e63ad4bd5dd ("x86/apic: Do not init irq remapping if ioapic is disabled")
>
>    ... added a check for skipped IO-APIC setup to enable_IR_x2apic(), but this

Could you tell me what is the meaning of "..." . How to use it?

>    check is also duplicated in try_to_enable_IR() - and it will never succeed in
>    calling irq_remapping_enable().
>
>    Remove the whole irq_remapping_enable() complication: if the IO-APIC is
>    disabled we cannot enable IRQ remapping.
>
> And I restored the original pr_info() message as well.

Yes. Thanks!

Sincerely,

	Liyang


>
> Thanks,
>
> 	Ingo
>
>
>