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Message-ID: <ce44cad1-8eab-4275-6c7a-6208265f3ae8@bytedance.com>
Date:   Mon, 24 Oct 2022 20:07:36 +0800
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Subject: Re: [External] Re: [PATCH 0/2] Optimize the process of scanning CPU
 for some functions
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     mingo@redhat.com, mingo@kernel.org, juri.lelli@redhat.com,
        vincent.guittot@linaro.org, dietmar.eggemann@arm.com,
        rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de,
        bristot@redhat.com, vschneid@redhat.com,
        mgorman@techsingularity.net, linux-kernel@vger.kernel.org
References: <20221021061558.34767-1-jiahao.os@bytedance.com>
 <Y1ZiKz1rxEcQ886D@hirez.programming.kicks-ass.net>
From:   Hao Jia <jiahao.os@bytedance.com>
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On 2022/10/24 Peter Zijlstra wrote:
> On Fri, Oct 21, 2022 at 02:15:56PM +0800, Hao Jia wrote:
>> These two patches optimize the process of scanning the CPU by
>> adjusting the search order or breaking the loop.
> 
> Is it really optimization, as in it now runs measurably faster, or just
> cleanups?


I'm very sorry that my description confused you.

Yes, these two patches should just be cleanups.

Reduce the number of attempts by adjusting the scan order or breaking 
the loop in time.
Just from code analysis, it will lead to a little optimization in most 
cases.
But they won't bring significant performance gains. So, it's just cleanups.


Thanks,
Hao