Re: [PATCH v4 09/11] x86/intel_pstate: add a booting param to select the driver to load

["Jan Beulich" <JBeulich@suse.com>]

>>> On 25.06.15 at 13:17, <wei.w.wang@intel.com> wrote:
> By default, the old P-state driver (acpi-freq) is used. Adding
> "intel_pstate" to the Xen booting param list to enable the
> use of intel_pstate. However, if intel_pstate is enabled on a
> machine which does not support the driver (e.g. Nehalem), the
> old P-state driver will be loaded due to the failure loading of
> intel_pstate.
> 
> Also, adding the intel_pstate booting parameter to
> xen-command-line.markdown.
> 
> v4 changes:
> 1) moved the definition of "load_intel_pstate" right ahead of
> intel_pstate_init();

Didn't I ask for it to be moved _inside_ the function?

> --- a/xen/arch/x86/acpi/cpufreq/intel_pstate.c
> +++ b/xen/arch/x86/acpi/cpufreq/intel_pstate.c
> @@ -831,12 +831,18 @@ static void __init copy_cpu_funcs(struct pstate_funcs *funcs)
>  	pstate_funcs.get_vid   = funcs->get_vid;
>  }
>  
> +static bool_t __initdata load_intel_pstate;
> +boolean_param("intel_pstate", load_intel_pstate);
> +
>  int __init intel_pstate_init(void)
>  {
>  	int cpu, rc = 0;
>  	const struct x86_cpu_id *id;
>  	struct cpu_defaults *cpu_info;
>  
> +	if (!load_intel_pstate)
> +		return -ENODEV;
> +

With the variable then perhaps simply be named "load"?

Jan