linux-kernel - Re: [PATCH] sched/fair: Move calculate of avg

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAKfTPtCv=pBDsvWDguFXtf_YZDf2Yx+xrpc3hDevQFz6BoadJA@mail.gmail.com>
Date:   Wed, 6 Apr 2022 17:21:58 +0200
From:   Vincent Guittot <vincent.guittot@...aro.org>
To:     zgpeng <zgpeng.linux@...il.com>
Cc:     mingo@...hat.com, peterz@...radead.org, juri.lelli@...hat.com,
        dietmar.eggemann@....com, rostedt@...dmis.org, bsegall@...gle.com,
        mgorman@...e.de, bristot@...hat.com, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] sched/fair: Move calculate of avg_load to a better location

On Wed, 6 Apr 2022 at 11:57, zgpeng <zgpeng.linux@...il.com> wrote:
>
> In calculate_imbalance function, when the value of local->avg_load is
> greater than or equal to busiest->avg_load, the calculated sds->avg_load is
> not used. So this calculation can be placed in a more appropriate position.
>
> Signed-off-by: zgpeng <zgpeng@...cent.com>
> Reviewed-by: Samuel Liao <samuelliao@...cent.com>

Reviewed-by: Vincent Guittot <vincent.guittot@...aro.org>

> ---
>  kernel/sched/fair.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index d4bd299..601f8bd 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -9460,8 +9460,6 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
>                 local->avg_load = (local->group_load * SCHED_CAPACITY_SCALE) /
>                                   local->group_capacity;
>
> -               sds->avg_load = (sds->total_load * SCHED_CAPACITY_SCALE) /
> -                               sds->total_capacity;
>                 /*
>                  * If the local group is more loaded than the selected
>                  * busiest group don't try to pull any tasks.
> @@ -9470,6 +9468,9 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
>                         env->imbalance = 0;
>                         return;
>                 }
> +
> +               sds->avg_load = (sds->total_load * SCHED_CAPACITY_SCALE) /
> +                               sds->total_capacity;
>         }
>
>         /*
> --
> 2.9.5
>