Re: [PATCH 04/11] PM / devfreq: Remove redundant frequency adjustment from governors

From: Chanwoo Choi
Date: Mon May 28 2018 - 01:36:20 EST


Hi,

On 2018ë 05ì 26ì 05:30, Matthias Kaehlcke wrote:
> The userspace and simpleondemand governor determine a target frequency and
> then adjust it according to the df->min/max_freq limits that might have
> been set by user space. This adjustment is redundant, it is done in
> update_devfreq() for any governor, right after returning from
> governor->get_target_freq().
>
> Signed-off-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
> ---
> drivers/devfreq/governor_simpleondemand.c | 5 -----
> drivers/devfreq/governor_userspace.c | 16 ++++------------
> 2 files changed, 4 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/devfreq/governor_simpleondemand.c b/drivers/devfreq/governor_simpleondemand.c
> index 278964783fa6..3da7554b4837 100644
> --- a/drivers/devfreq/governor_simpleondemand.c
> +++ b/drivers/devfreq/governor_simpleondemand.c
> @@ -84,11 +84,6 @@ static int devfreq_simple_ondemand_func(struct devfreq *df,
> b = div_u64(b, (dfso_upthreshold - dfso_downdifferential / 2));
> *freq = (unsigned long) b;
>
> - if (df->min_freq && *freq < df->min_freq)
> - *freq = df->min_freq;
> - if (df->max_freq && *freq > df->max_freq)
> - *freq = df->max_freq;
> -
> return 0;
> }
>
> diff --git a/drivers/devfreq/governor_userspace.c b/drivers/devfreq/governor_userspace.c
> index 080607c3f34d..378d84c011df 100644
> --- a/drivers/devfreq/governor_userspace.c
> +++ b/drivers/devfreq/governor_userspace.c
> @@ -26,19 +26,11 @@ static int devfreq_userspace_func(struct devfreq *df, unsigned long *freq)
> {
> struct userspace_data *data = df->data;
>
> - if (data->valid) {
> - unsigned long adjusted_freq = data->user_frequency;
> -
> - if (df->max_freq && adjusted_freq > df->max_freq)
> - adjusted_freq = df->max_freq;
> -
> - if (df->min_freq && adjusted_freq < df->min_freq)
> - adjusted_freq = df->min_freq;
> -
> - *freq = adjusted_freq;
> - } else {
> + if (data->valid)
> + *freq = data->user_frequency;
> + else
> *freq = df->previous_freq; /* No user freq specified yet */
> - }
> +
> return 0;
> }
>
>

Reviewed-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>

--
Best Regards,
Chanwoo Choi
Samsung Electronics