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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Francis Giraldeau <francis.giraldeau@gmail.com>
Cc: "linux-rt-users@vger.kernel.org" <linux-rt-users@vger.kernel.org>
Subject: Re: Timer tick not disabled with NO_HZ_FULL
Date: Wed, 3 Aug 2016 09:40:56 +0200	[thread overview]
Message-ID: <20160803074056.GA6741@linutronix.de> (raw)
In-Reply-To: <CAC6yHM4kTvXiJwsyFqmi3p_4U8a54wwUJz9QFHAGsO+aM6G6Wg@mail.gmail.com>

* Francis Giraldeau | 2016-07-29 16:56:15 [-0400]:

>It seems that the timer tick occurs with a PREEMPT_RT kernel even if configured
>with NO_HZ_FULL. On a real-time system where some cores are configured with
correct.

…
>This commit is quite old, maybe a solution exists to the problem of base timer
>locking. Would it be possible for instance to use RCU instead here to support
>NO_HZ_FULL with a PREEMPT_RT kernel?

Unfortunately RCU can't fix everything in its own magical way. But there
is hope! Since v4.6.4-rt8 we have NO_HZ_FULL working thanks to the timer
wheel rework.

>Thanks,
>
>Francis

Sebastian

  reply	other threads:[~2016-08-03  7:41 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-07-29 20:56 Timer tick not disabled with NO_HZ_FULL Francis Giraldeau
2016-08-03  7:40 ` Sebastian Andrzej Siewior [this message]
     [not found] ` <DDCAE26804250545B9934A2056554AA021106A54@ORSMSX112.amr.corp.intel.com>
2016-08-05  0:36   ` The timer softirq on the RT kernel yunhong jiang
2016-08-05  2:36     ` Mike Galbraith
2016-08-05 20:17       ` yunhong jiang

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