From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: Re: Timer tick not disabled with NO_HZ_FULL
Date: Wed, 3 Aug 2016 09:40:56 +0200
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To: Francis Giraldeau <francis.giraldeau@gmail.com>
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* 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