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Subject: Re: [patch 3/8] x86/apic: Provide apic_ack_irq()
To:     Thomas Gleixner <tglx@linutronix.de>
CC:     LKML <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Borislav Petkov <bp@alien8.de>,
        Dmitry Safonov <0x7f454c46@gmail.com>,
        Tariq Toukan <tariqt@mellanox.com>,
        Song Liu <liu.song.a23@gmail.com>,
        Joerg Roedel <jroedel@suse.de>,
        Mike Travis <mike.travis@hpe.com>, <stable@vger.kernel.org>
References: <20180604162224.471925894@linutronix.de>
 <94117bd8-352b-1077-e8ae-8722d7ec213f@cn.fujitsu.com>
 <alpine.DEB.2.21.1806051339020.1591@nanos.tec.linutronix.de>
 <de96585f-9b8d-4536-a9d5-32a718e3eb4d@cn.fujitsu.com>
 <alpine.DEB.2.21.1806061003310.1584@nanos.tec.linutronix.de>
From:   Dou Liyang <douly.fnst@cn.fujitsu.com>
Message-ID: <5db4a904-5ae4-fb1e-ff10-0ac6c1479ccd@cn.fujitsu.com>
Date:   Wed, 6 Jun 2018 16:18:10 +0800
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Hi Thomas,

At 06/06/2018 04:04 PM, Thomas Gleixner wrote:
> On Wed, 6 Jun 2018, Dou Liyang wrote:
> 
>> Hi Thomas,
>>
>> At 06/05/2018 07:41 PM, Thomas Gleixner wrote:
>>> On Tue, 5 Jun 2018, Dou Liyang wrote:
>>>>> +{
>>>>> +	if (unlikely(irqd_is_setaffinity_pending(irqd)))
>>>>
>>>> Affinity pending is also judged in
>>>>
>>>>> +		irq_move_irq(irqd);
>>>>
>>>> If we can remove the if(...) statement here
>>>
>>> That requires to fix all call sites in ia64 and that's why I didn't.  But
>>
>> I didn't express clearly, I meant remove the if(...) statement from
>> apic_ack_irq(), it doesn't require to fix the call sites in ia64.
> 
> I put the check there on purpose as I explained in the changelog:
> 
>     Making the invocation of irq_move_irq() conditional avoids the out of
>     line call if the pending bit is not set.
> 

I completely understand now, thank you so much. :-)

Thanks,
	dou

> Thanks,
> 
> 	tglx
> 
> 
>