Re: [PATCH v2] cpufreq: intel_pstate: Use cpu load based algorithm for PM_MOBILE

From: Rafael J. Wysocki
Date: Mon Nov 14 2016 - 16:12:46 EST


On Monday, November 14, 2016 10:31:11 AM Srinivas Pandruvada wrote:
> Use get_target_pstate_use_cpu_load() to calculate target P-State for
> devices, which uses preferred power management profile as PM_MOBILE
> in ACPI FADT.
> This may help in resolving some thermal issues caused by low sustained
> cpu bound workloads. The current algorithm tend to over provision in this
> case as it doesn't look at the CPU busyness.
>
> Also included the fix from Arnd Bergmann <arnd@xxxxxxxx> to solve compile
> issue, when CONFIG_ACPI is not defined.
>
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
> ---
> v2:
> Include fix from Arnd Bergmann for fixing compile issue
>
> drivers/cpufreq/intel_pstate.c | 14 ++++++++++++++
> 1 file changed, 14 insertions(+)
>
> diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
> index eb76073..9be0720 100644
> --- a/drivers/cpufreq/intel_pstate.c
> +++ b/drivers/cpufreq/intel_pstate.c
> @@ -1828,6 +1828,19 @@ static void __init copy_pid_params(struct pstate_adjust_policy *policy)
> pid_params.setpoint = policy->setpoint;
> }
>
> +#ifdef CONFIG_ACPI
> +static void intel_pstate_use_acpi_profile(void)
> +{
> + if (acpi_gbl_FADT.preferred_profile == PM_MOBILE)
> + pstate_funcs.get_target_pstate =
> + get_target_pstate_use_cpu_load;
> +}
> +#else
> +static void intel_pstate_use_acpi_profile(void)
> +{
> +}
> +#endif
> +
> static void __init copy_cpu_funcs(struct pstate_funcs *funcs)
> {
> pstate_funcs.get_max = funcs->get_max;
> @@ -1839,6 +1852,7 @@ static void __init copy_cpu_funcs(struct pstate_funcs *funcs)
> pstate_funcs.get_vid = funcs->get_vid;
> pstate_funcs.get_target_pstate = funcs->get_target_pstate;
>
> + intel_pstate_use_acpi_profile();
> }
>
> #ifdef CONFIG_ACPI
>

I've replaced the original commit with this patch.

Thanks,
Rafael