Re: [PATCH v4 3/4] sched/fair: Rework sched_use_asym_prio() and sched_asym_prefer()

[Ricardo Neri]

On Wed, Feb 07, 2024 at 11:47:03AM +0800, alexs@xxxxxxxxxx wrote:
> From: Alex Shi <alexs@xxxxxxxxxx>
> 
> sched_use_asym_prio() sched_asym_prefer() are used together in various

s/prio() sched/prio() and sched/

> places. Consolidate them into a single function sched_asym().
> 
> The existing sched_group_asym() is only used when collecting statistics
> of a scheduling group. Rename it as sched_group_asym().
> This makes the code easier to read. No functional changes.
> 
> Signed-off-by: Alex Shi <alexs@xxxxxxxxxx>
> To: Ricardo Neri <ricardo.neri-calderon@xxxxxxxxxxxxxxx>
> To: Valentin Schneider <vschneid@xxxxxxxxxx>
> To: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
> To: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> To: Ingo Molnar <mingo@xxxxxxxxxx>
> ---
>  kernel/sched/fair.c | 37 ++++++++++++++++++++-----------------
>  1 file changed, 20 insertions(+), 17 deletions(-)
> 
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 607dc310b355..942b6358f683 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -9746,8 +9746,18 @@ static bool sched_use_asym_prio(struct sched_domain *sd, int cpu)
>  	return sd->flags & SD_SHARE_CPUCAPACITY || is_core_idle(cpu);
>  }
>  
> +static inline bool sched_asym(struct sched_domain *sd, int dst_cpu, int src_cpu)
> +{
> +	/*
> +	 * First check if @dst_cpu can do asym_packing load balance. Only do it
> +	 * if it has higher priority than @src_cpu.
> +	 */
> +	return sched_use_asym_prio(sd, dst_cpu) &&
> +		sched_asym_prefer(dst_cpu, src_cpu);
> +}
> +
>  /**
> - * sched_asym - Check if the destination CPU can do asym_packing load balance
> + * sched_group_asym - Check if the destination CPU can do asym_packing balance
>   * @env:	The load balancing environment
>   * @sgs:	Load-balancing statistics of the candidate busiest group
>   * @group:	The candidate busiest group

After renaming and changing this function now its documentation has become
obsolete. Can you update it?