Re: [PATCH] cpufreq: intel_pstate: Simplify intel_pstate_update_perf_limits()

From: Chen Yu
Date: Fri Apr 09 2021 - 07:58:04 EST


On Wed, Apr 07, 2021 at 04:21:55PM +0200, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> Because pstate.max_freq is always equal to the product of
> pstate.max_pstate and pstate.scaling and, analogously,
> pstate.turbo_freq is always equal to the product of
> pstate.turbo_pstate and pstate.scaling, the result of the
> max_policy_perf computation in intel_pstate_update_perf_limits() is
> always equal to the quotient of policy_max and pstate.scaling,
> regardless of whether or not turbo is disabled. Analogously, the
> result of min_policy_perf in intel_pstate_update_perf_limits() is
> always equal to the quotient of policy_min and pstate.scaling.
>
> Accordingly, intel_pstate_update_perf_limits() need not check
> whether or not turbo is enabled at all and in order to compute
> max_policy_perf and min_policy_perf it can always divide policy_max
> and policy_min, respectively, by pstate.scaling. Make it do so.
>
> While at it, move the definition and initialization of the
> turbo_max local variable to the code branch using it.
>
> No intentional functional impact.
>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Tested-by: Chen Yu <yu.c.chen@xxxxxxxxx>