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Message-ID: <0dc761fe-3d98-8c80-8ee3-01804843e8f9@intel.com>
Date:   Wed, 31 Aug 2022 14:28:02 -0700
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Subject: Re: [PATCH] x86/acrn: Set up timekeeping
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To:     Fei Li <fei1.li@intel.com>, linux-kernel@vger.kernel.org,
        x86@kernel.org
Cc:     gregkh@linuxfoundation.org, tglx@linutronix.de, mingo@redhat.com,
        bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com,
        yu1.wang@intel.com, conghui.chen@intel.com
References: <20220804055903.365211-1-fei1.li@intel.com>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <20220804055903.365211-1-fei1.li@intel.com>
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On 8/3/22 22:59, Fei Li wrote:
> +static inline unsigned long acrn_get_tsc_khz(void)
> +{
> +	return cpuid_eax(ACRN_CPUID_TIMING_INFO);
> +}
> +
>  /*
>   * Hypercalls for ACRN
>   *
> diff --git a/arch/x86/kernel/cpu/acrn.c b/arch/x86/kernel/cpu/acrn.c
> index 23f5f27b5a02..485441b7f030 100644
> --- a/arch/x86/kernel/cpu/acrn.c
> +++ b/arch/x86/kernel/cpu/acrn.c
> @@ -28,6 +28,9 @@ static void __init acrn_init_platform(void)
>  {
>  	/* Setup the IDT for ACRN hypervisor callback */
>  	alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_acrn_hv_callback);
> +
> +	x86_platform.calibrate_tsc = acrn_get_tsc_khz;
> +	x86_platform.calibrate_cpu = acrn_get_tsc_khz;
>  }

Could you take a sec and consider what 'static inline' does and means
and also what setting:

	x86_platform.calibrate_cpu = acrn_get_tsc_khz;

does?

Using 'static inline' might compile, but it doesn't make sense.