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Date: Fri, 22 Nov 2013 13:59:26 -0500
From: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
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To: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
CC: David Ahern <dsahern@gmail.com>, mingo@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] perf util: optimize util/machine.c:machines__find().
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On 11/21/2013 07:06 PM, Arnaldo Carvalho de Melo wrote:
>
>> This changes machines__find to always return the machine for the
>> host (pid == 0). This function is also used for VM lookups.
> Nope:
>
> /* Native host kernel uses -1 as pid index in machine */
> #define HOST_KERNEL_ID                  (-1)
> #define DEFAULT_GUEST_KERNEL_ID         (0)
>
> But I fail to see the point of the "optimization", we're looking for a
> pid, not always for '0'.
>
> And the changelog is horrible, why is it "unnecessary"? Please don't be
> so terse :-)
>
> - Arnaldo
>

Hi David and Arnaldo,

     It is my mistake about it!! The original code does the right thing.
     Sorry to bother you, I am a newbie for perf.
     I will send a patch after second and third thought next time.

Thanx for your reply.

- Yang