Re: [PATCH] sched: move access of avg_rt and avg_dl into existing helper functions

From: Vincent Guittot
Date: Wed Dec 20 2023 - 08:59:57 EST


On Wed, 20 Dec 2023 at 07:55, Shrikanth Hegde
<sshegde@xxxxxxxxxxxxxxxxxx> wrote:
>
> This is a minor code simplification. There are helper functions called
> cpu_util_dl and cpu_util_rt which gives the average utilization of DL
> and RT respectively. But there are few places in code where these
> variables are used directly.
>
> Instead use the helper function so that code becomes simpler and easy to
> maintain later on.
>
> Signed-off-by: Shrikanth Hegde <sshegde@xxxxxxxxxxxxxxxxxx>
> ---
> kernel/sched/fair.c | 12 +++++-------
> 1 file changed, 5 insertions(+), 7 deletions(-)
>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index bcea3d55d95d..02631060ca7e 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -9212,19 +9212,17 @@ static inline bool cfs_rq_has_blocked(struct cfs_rq *cfs_rq)
>
> static inline bool others_have_blocked(struct rq *rq)
> {
> - if (READ_ONCE(rq->avg_rt.util_avg))
> + if (cpu_util_rt(rq))
> return true;
>
> - if (READ_ONCE(rq->avg_dl.util_avg))
> + if (cpu_util_dl(rq))
> return true;
>
> if (thermal_load_avg(rq))
> return true;
>
> -#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
> - if (READ_ONCE(rq->avg_irq.util_avg))
> + if (cpu_util_irq(rq))

cpu_util_irq doesn't call READ_ONCE()


> return true;
> -#endif
>
> return false;
> }
> @@ -9481,8 +9479,8 @@ static unsigned long scale_rt_capacity(int cpu)
> * avg_thermal.load_avg tracks thermal pressure and the weighted
> * average uses the actual delta max capacity(load).
> */
> - used = READ_ONCE(rq->avg_rt.util_avg);
> - used += READ_ONCE(rq->avg_dl.util_avg);
> + used = cpu_util_rt(rq);
> + used += cpu_util_dl(rq);
> used += thermal_load_avg(rq);
>
> if (unlikely(used >= max))
> --
> 2.39.3
>