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Date:   Fri, 30 Oct 2020 11:42:16 -0400
From:   Phil Auld <pauld@redhat.com>
To:     Hui Su <sh_def@163.com>
Cc:     mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com,
        vincent.guittot@linaro.org, dietmar.eggemann@arm.com,
        rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de,
        bristot@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sched/fair: remove the spin_lock operations
Message-ID: <20201030154216.GA142259@lorien.usersys.redhat.com>
References: <20201030144621.GA96974@rlk>
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In-Reply-To: <20201030144621.GA96974@rlk>
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On Fri, Oct 30, 2020 at 10:46:21PM +0800 Hui Su wrote:
> Since 'ab93a4bc955b ("sched/fair: Remove
> distribute_running fromCFS bandwidth")',there is
> nothing to protect between raw_spin_lock_irqsave/store()
> in do_sched_cfs_slack_timer().
> 
> So remove it.
> 
> Signed-off-by: Hui Su <sh_def@163.com>
> ---
>  kernel/sched/fair.c | 3 ---
>  1 file changed, 3 deletions(-)
> 
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 290f9e38378c..5ecbf5e63198 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -5105,9 +5105,6 @@ static void do_sched_cfs_slack_timer(struct cfs_bandwidth *cfs_b)
>  		return;
>  
>  	distribute_cfs_runtime(cfs_b);
> -
> -	raw_spin_lock_irqsave(&cfs_b->lock, flags);
> -	raw_spin_unlock_irqrestore(&cfs_b->lock, flags);
>  }
>  
>  /*
> -- 
> 2.29.0
> 
> 

Nice :)

Reviewed-by: Phil Auld <pauld@redhat.com>
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