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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Tue, 14 Nov 2017 16:34:43 -0800
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Subject: Re: [PATCH] x86: use cpufreq_quick_get() for /proc/cpuinfo "cpu MHz" again
To: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>, WANG Chao <chao.wang@ucloud.cn>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
        Vikas Shivappa <vikas.shivappa@linux.intel.com>,
        Kate Stewart <kstewart@linuxfoundation.org>,
        Len Brown <len.brown@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Philippe Ombredanne <pombredanne@nexb.com>,
        Mathias Krause <minipli@googlemail.com>,
        "the arch/x86 maintainers" <x86@kernel.org>,
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        "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
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On Tue, Nov 14, 2017 at 4:30 PM, Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
>
> OK, so may I queue it up?
>
> I don't think I can get that to work substantially faster anyway ...

Yeah, I think it's ok.

If somebody is really doing that /proc/cpuinfo in a loop, the rate
limiting should kick in. And if you do it only once, getting the right
frequency is worth it, I think.

             Linus