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From: Frederic Weisbecker <frederic@kernel.org>
To: Yunfeng Ye <yeyunfeng@huawei.com>
Cc: fweisbec@gmail.com, tglx@linutronix.de, mingo@kernel.org,
	linux-kernel@vger.kernel.org, Shiyuan Hu <hushiyuan@huawei.com>,
	Hewenliang <hewenliang4@huawei.com>
Subject: Re: nohz: Update tick instead of restarting tick in tick_nohz_idle_exit()
Date: Fri, 27 Nov 2020 13:15:42 +0100	[thread overview]
Message-ID: <20201127121542.GA109224@lothringen> (raw)
In-Reply-To: <66014fea-7b84-358b-137d-d15190241528@huawei.com>

On Mon, Nov 23, 2020 at 09:22:08PM +0800, Yunfeng Ye wrote:
> In realtime scenarios, the "nohz_full" parameter is configured. Tick
> interference is not expected when there is only one realtime thread.
> But when the idle thread is switched to the realtime thread, the tick
> timer is restarted always.
> 
> So on the nohz full mode, it is unnecessary to restart the tick timer
> when there is only one realtime thread. Adding can_stop_full_tick()
> before restarting the tick, if it return true, keep tick stopped.
> 
> Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>

We can indeed stop the tick and avoid it to be re-armed needlessly at this
point.

I'm taking your patch, I may just edit it a little and resend it.

Thanks!

  reply	other threads:[~2020-11-27 12:16 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-23 13:22 nohz: Update tick instead of restarting tick in tick_nohz_idle_exit() Yunfeng Ye
2020-11-27 12:15 ` Frederic Weisbecker [this message]
2020-11-28  0:32   ` Yunfeng Ye
2021-02-19 12:16 ` Frederic Weisbecker
2021-02-19 13:08   ` Yunfeng Ye

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