Re: [PATCH v4 2/2] sched/rt, dl: Convert functions to return bool

[Metin Kaya]

On 01/06/2024 10:33 pm, Qais Yousef wrote:
> {rt, realtime, dl}_{task, prio}() functions return value is actually
> a bool.  Convert their return type to reflect that.
>
> Suggested-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
> Signed-off-by: Qais Yousef <qyousef@xxxxxxxxxxx>
> ---
>   include/linux/sched/deadline.h |  8 ++++----
>   include/linux/sched/rt.h       | 16 ++++++++--------
>   2 files changed, 12 insertions(+), 12 deletions(-)
>
> diff --git a/include/linux/sched/deadline.h b/include/linux/sched/deadline.h
> index 5cb88b748ad6..f2053f46f1d5 100644
> --- a/include/linux/sched/deadline.h
> +++ b/include/linux/sched/deadline.h
> @@ -10,18 +10,18 @@
>   
>   #include <linux/sched.h>
>   
> -static inline int dl_prio(int prio)
> +static inline bool dl_prio(int prio)
>   {
>   	if (unlikely(prio < MAX_DL_PRIO))
> -		return 1;
> -	return 0;
> +		return true;
> +	return false;

Nit: `return unlikely(prio < MAX_DL_PRIO)` would be simpler.
The same can be applied to rt_prio() and realtime_prio(). This would 
make {dl, rt, realtime}_task() single-liner. Maybe further 
simplification can be done.

>   }
>   
>   /*
>    * Returns true if a task has a priority that belongs to DL class. PI-boosted
>    * tasks will return true. Use dl_policy() to ignore PI-boosted tasks.
>    */
> -static inline int dl_task(struct task_struct *p)
> +static inline bool dl_task(struct task_struct *p)
>   {
>   	return dl_prio(p->prio);
>   }
> diff --git a/include/linux/sched/rt.h b/include/linux/sched/rt.h
> index a055dd68a77c..efbdd2e57765 100644
> --- a/include/linux/sched/rt.h
> +++ b/include/linux/sched/rt.h
> @@ -6,25 +6,25 @@
>   
>   struct task_struct;
>   
> -static inline int rt_prio(int prio)
> +static inline bool rt_prio(int prio)
>   {
>   	if (unlikely(prio < MAX_RT_PRIO && prio >= MAX_DL_PRIO))
> -		return 1;
> -	return 0;
> +		return true;
> +	return false;
>   }
>   
> -static inline int realtime_prio(int prio)
> +static inline bool realtime_prio(int prio)
>   {
>   	if (unlikely(prio < MAX_RT_PRIO))
> -		return 1;
> -	return 0;
> +		return true;
> +	return false;
>   }
>   
>   /*
>    * Returns true if a task has a priority that belongs to RT class. PI-boosted
>    * tasks will return true. Use rt_policy() to ignore PI-boosted tasks.
>    */
> -static inline int rt_task(struct task_struct *p)
> +static inline bool rt_task(struct task_struct *p)
>   {
>   	return rt_prio(p->prio);
>   }
> @@ -34,7 +34,7 @@ static inline int rt_task(struct task_struct *p)
>    * PI-boosted tasks will return true. Use realtime_task_policy() to ignore
>    * PI-boosted tasks.
>    */
> -static inline int realtime_task(struct task_struct *p)
> +static inline bool realtime_task(struct task_struct *p)
>   {
>   	return realtime_prio(p->prio);
>   }