From mboxrd@z Thu Jan  1 00:00:00 1970
From: Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [OSADL QA 3.18.9-rt5 #1]
Date: Wed, 13 May 2015 11:23:56 -0400
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Cc: Carsten Emde <C.Emde@osadl.org>,
	Linux RT Users <linux-rt-users@vger.kernel.org>
To: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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On Wed, 13 May 2015 10:12:36 +0200
Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:

> * Steven Rostedt | 2015-05-11 20:15:06 [-0400]:
> 
> >I'm backporting this to the stable releases, and I'm a bit worried
> >about the above comment. The new Scheduler IPI code uses work queues and
> >requires it to be done in a hard irq.
> 
> The IPI part is only done for the high-prio which is only used by NOHZ.
> Everyone else gets in via softiq as we did it before.
> 

My push/pull RT tasks via IPI, uses the irq_work to do this. It has
nothing to do with NOHZ, and will cause serious latencies if it is done
by softirq.

-- Steve