linux-kernel - Re: [PATCH v2 5/8] thermal: gov_power_allocator: Refactor checks in divvy_up

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Date: Wed, 20 Dec 2023 15:41:41 +0100
From: "Rafael J. Wysocki" <rafael@...nel.org>
To: Lukasz Luba <lukasz.luba@....com>
Cc: linux-kernel@...r.kernel.org, daniel.lezcano@...aro.org, rafael@...nel.org, 
	linux-pm@...r.kernel.org, rui.zhang@...el.com
Subject: Re: [PATCH v2 5/8] thermal: gov_power_allocator: Refactor checks in divvy_up_power()

On Tue, Dec 12, 2023 at 2:48 PM Lukasz Luba <lukasz.luba@....com> wrote:
>
> Simplify the code and remove one extra 'if' block.
>
> No intentional functional impact.
>
> Signed-off-by: Lukasz Luba <lukasz.luba@....com>
> ---
>  drivers/thermal/gov_power_allocator.c | 20 ++++++++++----------
>  1 file changed, 10 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/thermal/gov_power_allocator.c b/drivers/thermal/gov_power_allocator.c
> index 1a605fd9c8c6..574aa5822112 100644
> --- a/drivers/thermal/gov_power_allocator.c
> +++ b/drivers/thermal/gov_power_allocator.c
> @@ -349,7 +349,8 @@ static void divvy_up_power(u32 *req_power, u32 *max_power, int num_actors,
>                            u32 total_req_power, u32 power_range,
>                            u32 *granted_power, u32 *extra_actor_power)
>  {
> -       u32 extra_power, capped_extra_power;
> +       u32 capped_extra_power = 0;
> +       u32 extra_power = 0;
>         int i;
>
>         /*
> @@ -358,8 +359,6 @@ static void divvy_up_power(u32 *req_power, u32 *max_power, int num_actors,
>         if (!total_req_power)
>                 total_req_power = 1;
>
> -       capped_extra_power = 0;
> -       extra_power = 0;
>         for (i = 0; i < num_actors; i++) {
>                 u64 req_range = (u64)req_power[i] * power_range;
>
> @@ -375,7 +374,7 @@ static void divvy_up_power(u32 *req_power, u32 *max_power, int num_actors,
>                 capped_extra_power += extra_actor_power[i];
>         }
>
> -       if (!extra_power)
> +       if (!extra_power || !capped_extra_power)
>                 return;
>
>         /*
> @@ -383,12 +382,13 @@ static void divvy_up_power(u32 *req_power, u32 *max_power, int num_actors,
>          * how far they are from the max
>          */
>         extra_power = min(extra_power, capped_extra_power);
> -       if (capped_extra_power > 0)
> -               for (i = 0; i < num_actors; i++) {
> -                       u64 extra_range = (u64)extra_actor_power[i] * extra_power;
> -                       granted_power[i] += DIV_ROUND_CLOSEST_ULL(extra_range,
> -                                                        capped_extra_power);
> -               }
> +
> +       for (i = 0; i < num_actors; i++) {
> +               u64 extra_range = (u64)extra_actor_power[i] * extra_power;
> +
> +               granted_power[i] += DIV_ROUND_CLOSEST_ULL(extra_range,
> +                                                capped_extra_power);
> +       }
>  }
>
>  static int allocate_power(struct thermal_zone_device *tz, int control_temp)
> --

Looks good to me.