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From:   Andy Lutomirski <luto@kernel.org>
Date:   Sat, 8 Jun 2019 15:52:03 -0700
Message-ID: <CALCETrWi+uM5Rch6vaXOwHsHas928CDY5VJoBYaudD+3VFTrNw@mail.gmail.com>
Subject: Re: [PATCH v4 3/5] x86/umwait: Add sysfs interface to control umwait
 C0.2 state
To:     Fenghua Yu <fenghua.yu@intel.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        H Peter Anvin <hpa@zytor.com>,
        Andy Lutomirski <luto@kernel.org>,
        Ashok Raj <ashok.raj@intel.com>,
        Tony Luck <tony.luck@intel.com>,
        Ravi V Shankar <ravi.v.shankar@intel.com>,
        linux-kernel <linux-kernel@vger.kernel.org>, x86 <x86@kernel.org>
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On Fri, Jun 7, 2019 at 3:10 PM Fenghua Yu <fenghua.yu@intel.com> wrote:
>
> C0.2 state in umwait and tpause instructions can be enabled or disabled
> on a processor through IA32_UMWAIT_CONTROL MSR register.
>

> +static u32 get_umwait_control_c02(void)
> +{
> +       return umwait_control_cached & MSR_IA32_UMWAIT_CONTROL_C02;
> +}
> +
> +static u32 get_umwait_control_max_time(void)
> +{
> +       return umwait_control_cached & MSR_IA32_UMWAIT_CONTROL_MAX_TIME;
> +}
> +

I'm not convinced that these helpers make the code any more readable.