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Reply-To: zhenzhong.duan@oracle.com
Subject: Re: [PATCH] tick/broadcast: Remove redundant code in
 tick_check_new_device()
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     mingo@kernel.org, fweisbec@gmail.com,
        Srinivas REDDY Eeda <srinivas.eeda@oracle.com>,
        Joe Jin <joe.jin@oracle.com>, linux-kernel@vger.kernel.org
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 <alpine.DEB.2.20.1711131738140.1851@nanos>
From:   Zhenzhong Duan <zhenzhong.duan@oracle.com>
Organization: Oracle
Message-ID: <374b90a7-1a7a-5775-73d5-e204bfc69a65@oracle.com>
Date:   Tue, 14 Nov 2017 11:29:26 +0800
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On 2017/11/14 0:54, Thomas Gleixner wrote:

> On Wed, 8 Nov 2017, Zhenzhong Duan wrote:
>
>> There is no way a timer used as broadcast clockevent device is also used as
>> percpu tick clockevent device currently.
> Correct.
>
>> It's better to put related code in tick_install_broadcast_device(), but I feel
>> it's harmless to give it back to the clockevents layer. Pls correct me if I'm
>> wrong.
> You already established, that it _cannot_ be the broadcast device and the
> per cpu device at the same time. So that condition can never be true. What
> do you want to put into tick_install_broadcast_device()? This second
> paragraph doesn't make sense, unless I'm missing something.

I didn't find the reason in long history logs while the comments saying 'If the current device is the broadcast device, do not give it back to the clockevents layer !'

If it does, tick_install_broadcast_device() is a proper place. If not, I can resend the patch with fresh description, pls confirm.

-- 
thanks
zduan


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