linux-kernel - Re: [PATCH] cpufreq: Remove references to 10ms min sampling rate

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Date: Thu, 22 Feb 2024 20:31:38 +0100
From: "Rafael J. Wysocki" <rafael@...nel.org>
To: Pierre Gondois <pierre.gondois@....com>
Cc: linux-kernel@...r.kernel.org, Qais Yousef <qyousef@...alina.io>, 
	"Rafael J. Wysocki" <rafael@...nel.org>, Viresh Kumar <viresh.kumar@...aro.org>, linux-pm@...r.kernel.org
Subject: Re: [PATCH] cpufreq: Remove references to 10ms min sampling rate

On Thu, Feb 22, 2024 at 4:35 PM Pierre Gondois <pierre.gondois@....com> wrote:
>
> A minimum sampling rate value of 10ms was introduced in:
> commit cef9615a853e ("[CPUFREQ] ondemand: Uncouple minimal sampling rate from HZ in NO_HZ case")
>
> The use of this value was removed in:
> commit ed4676e25463 ("cpufreq: Replace "max_transition_latency" with "dynamic_switching"")
>
> Remove:
> - a comment referencing this value
> - an unused macro associated to this value
>
> Signed-off-by: Pierre Gondois <pierre.gondois@....com>
> ---
>  drivers/cpufreq/cpufreq_ondemand.c | 1 -
>  include/linux/cpufreq.h            | 4 +---
>  2 files changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
> index c52d19d67557..a7c38b8b3e78 100644
> --- a/drivers/cpufreq/cpufreq_ondemand.c
> +++ b/drivers/cpufreq/cpufreq_ondemand.c
> @@ -22,7 +22,6 @@
>  #define DEF_SAMPLING_DOWN_FACTOR               (1)
>  #define MAX_SAMPLING_DOWN_FACTOR               (100000)
>  #define MICRO_FREQUENCY_UP_THRESHOLD           (95)
> -#define MICRO_FREQUENCY_MIN_SAMPLE_RATE                (10000)
>  #define MIN_FREQUENCY_UP_THRESHOLD             (1)
>  #define MAX_FREQUENCY_UP_THRESHOLD             (100)
>
> diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
> index 8b9026031a28..625949a1869d 100644
> --- a/include/linux/cpufreq.h
> +++ b/include/linux/cpufreq.h
> @@ -568,9 +568,7 @@ static inline unsigned long cpufreq_scale(unsigned long old, u_int div,
>
>  /*
>   * The polling frequency depends on the capability of the processor. Default
> - * polling frequency is 1000 times the transition latency of the processor. The
> - * ondemand governor will work on any processor with transition latency <= 10ms,
> - * using appropriate sampling rate.
> + * polling frequency is 1000 times the transition latency of the processor.
>   */
>  #define LATENCY_MULTIPLIER             (1000)
>
> --

Applied as 6.9 material, thanks!