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Subject: Re: [PATCH 1/2] x86/tsc: Avoid a double call if TSC initializes
 earlier.
To:     Peter Zijlstra <peterz@infradead.org>
CC:     <linux-kernel@vger.kernel.org>, <x86@kernel.org>,
        <tglx@linutronix.de>, <mingo@redhat.com>, <hpa@zytor.com>,
        Pavel Tatashin <pasha.tatashin@oracle.com>
References: <20180730075421.22830-1-douly.fnst@cn.fujitsu.com>
 <20180730075421.22830-2-douly.fnst@cn.fujitsu.com>
 <20180730093447.GF2494@hirez.programming.kicks-ass.net>
From:   Dou Liyang <douly.fnst@cn.fujitsu.com>
Message-ID: <a2d372a3-a7cc-34ae-679d-cf71d243ee04@cn.fujitsu.com>
Date:   Mon, 30 Jul 2018 17:53:44 +0800
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Hi Peter,

At 07/30/2018 05:34 PM, Peter Zijlstra wrote:
> On Mon, Jul 30, 2018 at 03:54:20PM +0800, Dou Liyang wrote:
>> static_branch_enable(&__use_tsc) may be called twice in common case, that
>> is redundant.
> 
> It is also really not a problem...
> 

Yes, right. Just avoid the second useless setting.

Thanks,
	dou

> 
>