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From:   Thomas Gleixner <tglx@linutronix.de>
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To:     "shenkai \(D\)" <shenkai8@huawei.com>,
        Andy Lutomirski <luto@kernel.org>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        X86 ML <x86@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>,
        hewenliang4@huawei.com, hushiyuan@huawei.com,
        luolongjun@huawei.com, hejingxian@huawei.com
Subject: Re: [PATCH] use x86 cpu park to speedup smp_init in kexec situation
In-Reply-To: <f2a4d172-fa17-9f98-ad8f-d69f84ad0df5@huawei.com>
References: <87eejqu5q5.fsf@nanos.tec.linutronix.de> <f2a4d172-fa17-9f98-ad8f-d69f84ad0df5@huawei.com>
Date:   Wed, 16 Dec 2020 11:12:49 +0100
Message-ID: <87v9d2rrdq.fsf@nanos.tec.linutronix.de>
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Kai,

On Wed, Dec 16 2020 at 16:45, shenkai wrote:
> =E5=9C=A8 2020/12/16 5:20, Thomas Gleixner =E5=86=99=E9=81=93:
>>
>>
> Thanks for your and Andy's precious comments. I would like to take a try =
on
>
> reconstructing this patch to make it more decent and generic.

>> It would be interesting to see the numbers just with play_dead() using
>> hlt() or mwait(eax=3D0, 0) for the kexec case and no other change at all.

Can you please as a first step look into this and check if the time
changes?

Thanks,

        tglx