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Message-ID: <651dbb96-8d6e-53e9-a99f-0bb12f5b2723@redhat.com>
Date:   Fri, 26 Aug 2022 09:15:38 +0200
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Subject: Re: [PATCH -next] sched/deadline: Add start_new_instance helper
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To:     Shang XiaoJing <shangxiaojing@huawei.com>
References: <20220826031521.13391-1-shangxiaojing@huawei.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,
        vschneid@redhat.com, linux-kernel@vger.kernel.org
From:   Daniel Bristot de Oliveira <bristot@redhat.com>
In-Reply-To: <20220826031521.13391-1-shangxiaojing@huawei.com>
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On 8/26/22 05:15, Shang XiaoJing wrote:
> Wrap repeated code in helper function start_new_instance, which set
> the deadline and runtiem of input dl_se based on pi_of(dl_se). Note that
                      ^ runtime
> setup_new_dl_entity originally set the deadline and runtime base on
> dl_se, which should equals to pi_of(dl_se) for non-boosted task.
> 
> Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
> ---
>  kernel/sched/deadline.c | 22 ++++++++++++----------
>  1 file changed, 12 insertions(+), 10 deletions(-)
> 
> diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
> index 4a40a462717c..5e9c28847610 100644
> --- a/kernel/sched/deadline.c
> +++ b/kernel/sched/deadline.c
> @@ -770,6 +770,13 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags);
>  static void __dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags);
>  static void check_preempt_curr_dl(struct rq *rq, struct task_struct *p, int flags);

again, this is not a good function name. Maybe, dl_replenish_new_period() ?

> +static inline void start_new_instance(struct sched_dl_entity *dl_se, struct rq *rq)
> +{
> +	/* for non-boosted task, pi_of(dl_se) == dl_se */
> +	dl_se->deadline = rq_clock(rq) + pi_of(dl_se)->dl_deadline;
> +	dl_se->runtime = pi_of(dl_se)->dl_runtime;
> +}
> +

-- Daniel