linux-kernel - Re: [PATCH] sched/core: Remove useless hrtimer

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Date:   Tue, 10 Jul 2018 18:08:48 +0200
From:   Daniel Lezcano <daniel.lezcano@...aro.org>
To:     peterz@...radead.org
Cc:     linux-kernel@...r.kernel.org, Ingo Molnar <mingo@...hat.com>
Subject: Re: [PATCH] sched/core: Remove useless hrtimer_active check

On 19/06/2018 16:02, Daniel Lezcano wrote:
> The function tick_clear() checks if the timer is active and in this case
> cancels the timer. However, hrtimer_cancel does the same check.
> 
> Perhaps, this test is made on purpose to skip some function calls for
> efficiency reasons but if it is not the case we can safely remove it.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@...aro.org>
> ---
>  kernel/sched/core.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index d155518..aa46aa6 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -218,8 +218,7 @@ void update_rq_clock(struct rq *rq)
>  
>  static void hrtick_clear(struct rq *rq)
>  {
> -	if (hrtimer_active(&rq->hrtick_timer))
> -		hrtimer_cancel(&rq->hrtick_timer);
> +	hrtimer_cancel(&rq->hrtick_timer);
>  }
>  
>  /*

May be not the patch of the century but just a gentle bump if it was
lost by more important patchset review.


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